Entrada Therapeutics Inc

Overview

We are a clinical-stage biopharmaceutical company aiming to transform the lives of patients by establishing a new class of medicines which engage intracellular targets that have long been considered inaccessible. The Company’s Endosomal Escape Vehicle (EEV™)-therapeutics are designed to enable the efficient delivery of a wide range of therapeutics into a variety of organs and tissues, resulting in an improved therapeutic index. Through our proprietary, highly versatile and modular EEV platform (EEV Platform), we are building a robust development portfolio of therapeutic candidates. Our first two drug candidates, ENTR-601-44 and VX-670 (previously referred to as ENTR-701), are in clinical trials, and we expect to initiate additional regulatory filings by the end of 2024. We believe that the potential success of our early programs can translate into the efficient development of additional EEV therapeutic candidates and allow us to build portfolios in neuromuscular disease and beyond.

Lead Neuromuscular Programs

We are initially focused on the development of EEV therapeutics for rare neuromuscular diseases, starting with Duchenne muscular dystrophy (Duchenne or DMD). DMD is caused by genetic mutations that prevent the creation of functional dystrophin, a protein required to maintain the structural integrity of muscle cells. In our neuromuscular disease programs, we link EEVs to small strands of nucleic acids called oligonucleotides, including phosphorodiamidate morpholino oligomers (PMOs). We are developing EEV-PMOs that promote the skipping of these mutations associated with DMD. We believe that our EEV-PMO exon-skipping therapy will enable the production of functional dystrophin to slow, stop or even reverse disease progression. Our most advanced therapeutic candidate, ENTR-601-44, is being developed for patients with DMD that are exon 44 skipping amenable. On July 24, 2023, Entrada received authorization from the United Kingdom Medicines and Healthcare Products Regulatory Agency (MHRA) and Research Ethics Committee (REC) for its CTIMP (Clinical Trial of an Investigational Medicinal Product) for its Phase 1 clinical trial in healthy volunteers, ENTR-601-44-101. On March 13, 2024, we announced that the first, second and third cohorts of participants had been successfully dosed and we expect to report data from the Phase 1 clinical trial in the second half of 2024. On December 19, 2022, we announced that we received a clinical hold notice from the FDA regarding the IND application for ENTR-601-44. The FDA has requested that we continue to gather and submit additional information regarding ENTR-601-44 and we are actively working to resolve the clinical hold in the United States.

In 2023 we also announced the selection of additional clinical candidates within our Duchenne franchise ENTR-601-45 and ENTR-601-50. We plan to submit Phase 2 enabling regulatory applications for ENTR-601-44 and ENTR-601-45 in the fourth quarter of 2024, and for ENTR-601-50 in 2025.

Duchenne Muscular Dystrophy Franchise Summary

•ENTR-601-44: Phase 1 clinical trials are ongoing with clinical data expected H2 2024 and Phase 2 regulatory submissions expected in Q4 2024

•ENTR-601-45: Expect to submit Clinical Trial Application (CTA)/IND Q4 2024

•ENTR-601-50: Expect to submit CTA/IND in 2025

•Exon 51: Candidate selection expected in 2024

We are also supporting the development of a program for patients with DM1 as part of our collaboration with Vertex Pharmaceuticals Incorporated (Vertex). Patients with DM1 carry extra cytosine-uracil-guanine (CUG) triplet repeats that result in misprocessing of several proteins and multisystemic clinical manifestations. VX-670 for DM1 is designed to block the triplet repeats in the messenger RNA (mRNA) that sequesters these critical proteins and restore muscle function. We and Vertex entered into a Strategic Collaboration and License Agreement, which was amended in October 2023, (the Vertex Agreement) pursuant to which the Company granted Vertex an exclusive worldwide license to research, develop, manufacture, and commercialize VX-670 as well as any additional EEV-based therapeutic candidates that may be identified by the Company for the potential treatment of DM1 in the course of the parties’ four-year global research collaboration. On January 7, 2024, Vertex announced authorization from the MHRA of a clinical trial application for VX-670 for patients with DM1 and initiation of a Phase 1/2 clinical trial in patients with DM1 in Canada. Vertex also noted that it submitted an IND application and that the FDA requested additional information, which resulted in a clinical hold. Vertex is working to address the FDA's comments in order to initiate the study in the U.S.

Platform and Pipeline

Approximately 75% of all disease-causing targets are located inside cells. Intracellular therapeutics are designed to correct disease-causing dysfunction inside cells, addressing targets at the level of DNA, RNA or protein. In order to do so, these therapeutics need to first get through the cell’s membrane, which is a phospholipid bilayer, and then escape from the cell’s transportation and sorting vehicle, known as the early endosome, in order to reach and engage with their intended targets. Small molecules can permeate cell membranes but tend to be rapidly cleared by the body before they reach the intended tissue and can be associated with off-target effects. These limitations often necessitate high therapeutic doses and can be associated with less-than-optimal therapeutic activity. Biological therapeutics are generally potent and specific with respect to their intracellular targets of interest but limited in their ability to reach such targets, often lacking the ability to efficiently penetrate the cell membrane and then escape from the early endosome.

We believe our EEV Platform can enable the efficient intracellular delivery of specific and potent therapeutics. The following key attributes of our EEV Platform have allowed us to develop broadly distributed, EEV therapeutic candidates, which have been observed to be pharmacologically or biologically active and targeted with respect to the engagement or involvement with a desired intracellular target of interest.

•Serum stability and extended half-life: Based on preclinical studies, we have observed that EEVs have increased stability and extended half-life due to their unique cyclic structure, which limits protease-mediated degradation. We believe this may enable increased systemic exposure.

•Broad biodistribution: EEVs target phospholipid bilayers, which we believe can enable delivery to any cell in the body, regardless of route of administration. We have shown biodistribution to a wide range of organs, tissues and cells in our preclinical studies, including cardiac muscle, the cerebellum and macrophages, among many others.

•Active uptake and drug release: EEVs generally avoid being trapped in the cell membrane and are instead taken up into the cell by the early endosome. EEVs then enable budding of vesicles from the early endosome, which we believe substantially increase the level of therapeutics reaching intended targets within the cell.

We believe our EEV Platform can offer meaningful advantages over existing therapeutic approaches, including:

•Broad potential therapeutic index based on observations in preclinical studies. We believe EEV therapeutic candidates can engage targets across various organs and tissues with up to 50 times greater intracellular target exposure compared with a similar dose regimen of an unconjugated therapeutic.

•Potential utility across multiple modalities due to the ability of EEVs to facilitate intracellular uptake of proprietary therapeutic candidates ranging in size from 1 kDa to 600 kDa, including oligonucleotides, peptides, antibodies and larger multimeric proteins.

•Potential applicability to a wide range of diseases as we believe EEVs can enter cells by binding with the phospholipid bilayer which is common to all cells, tissues and organs in the body. This may imply an ability to achieve both systemic and specific delivery of potential therapeutic candidates for a wide range of diseases.

•Multiple delivery routes possible including intravenous (IV), intramuscular (IM), subcutaneous (SQ) and intrathecal (IT) injections to deliver our EEV therapeutic candidates and generate functional outcomes.

•Modular approach supports efficient expansion of development into multiple therapeutic areas, including oligonucleotide therapies in neuromuscular and non-neuromuscular applications.

•Translatability, as the mechanisms of cell entry and endosomal escape are thought to be conserved across species.

•A simple and scalable construct designed to translate from preclinical to clinical development as our lead EEV has been manufactured efficiently at both clinical and commercial scale.

We are engaged in preclinical lead optimization efforts in both neuromuscular and non-neuromuscular disease and discovery efforts to advance platform applications including through novel moiety and delivery modality combinations.

In neuromuscular disease, we are initially focused on the development of disease-modifying treatments for DMD. DMD is a monogenic X-linked disease caused by mutations in the DMD gene, which encodes for the protein dystrophin. We estimate that DMD occurs in approximately one in every 3,500 to 5,000 live male births and that the patient population is approximately 30,000 patients in the aggregate in the United States and Europe. Approximately 80% of patients have mutations amenable to exon skipping in the nucleus. We are developing therapeutic candidates to address the genetic basis, at the exon-specific level, of DMD. EEV oligonucleotides are designed to promote the skipping of exon mutations associated with DMD, enabling muscle cells to create a functional dystrophin at a level that we believe may slow, stop or even reverse DMD progression. Our most advanced programs include ENTR-601-44, for the 7.6% of patients with DMD that are exon 44 skipping amenable, ENTR-601-45 for the 8.1% of DMD patients who are exon 45 skipping amenable and ENTR-601-50 for the 3.8% of patients with DMD that are exon 50 skipping amenable. We believe there is robust preclinical data that supports the development of these programs. In our preclinical studies, we have observed substantial exon skipping and dystrophin production in patient derived cells and significant levels of exon skipping in humanized DMD mice and NHPs. This exon skipping was durable 12 weeks after a single dose and has been shown to accumulate after multiple doses, despite rapid clearance from serum. We have shown an ability to optimize the PMO conjugate and deliver a multi-fold improvement in exon skipping over a commercially available sequence, even when that sequence is conjugated to an EEV. Our preclinical studies have also demonstrated reductions in serum creatine kinase (CK), which is a commonly-used biomarker of muscle breakdown, to wild-type levels. Correction of CK is believed to be a strong indicator of pharmacodynamic activity throughout the body and has been described in medical literature as a marker of muscle integrity. We have observed corresponding and significant improvements in functional outcomes as measured in the D2-mdx mouse. In particular, we have observed meaningful tissue uptake and exon skipping, ranging from approximately 60% to over 95% depending on the tissue, in the D2-mdx mouse. We have demonstrated that repeat dosing allows for a halving of the single dose administered in the D2-mdx mouse while maintaining exon skipping efficacy. We have seen increases in both exon skipping and dystrophin production in skeletal and cardiac muscle after multiple doses even allowing for a six week washout between doses, and close to 100% dystrophin positive fibers after only the second dose. In EEV-PMO treated tissues we observed substantial restoration of both dystrophin and alpha sarcoglycan. In striated muscle, sarcoglycans interact with dystrophin and other dystrophin-associated proteins to form the dystrophin-associated glycoprotein complex which protects the sarcolemma from contraction-induced injury.

On July 24, 2023, we received authorization from the MHRA for our Phase 1 clinical trial in healthy volunteers, ENTR-601-44-101. The Phase 1 clinical trial's primary objective is to evaluate the safety and tolerability of a single dose of ENTR-601-44 in healthy volunteers, with a target enrollment of approximately 40 participants. The trial will also evaluate pharmacokinetics and target engagement as measured by exon skipping in the skeletal muscle, bearing the Company's recentin vitro data showed that exon skipping was approximately 10-40x higher in dystrophic muscle compared to healthy muscle, suggesting that data from healthy normal volunteers may substantially underestimate potential potency. On March 13, 2024, we announced that the first, second and third cohorts of participants had been successfully dosed and we expect to report data from the Phase 1 clinical trial in the second half of 2024. The data from this trial will inform our global clinical development strategy, and if favorable, support regulatory filings to open a global multiple ascending dose (MAD) Phase 2 trial in the fourth quarter of 2024. It is expected that countries will be included in the trial on a rolling basis, as dependent on discussions with individual regulators.

On January 9, 2023, we announced the selection of a second clinical candidate within our Duchenne franchise, ENTR-601-45, for the potential treatment of people living with DMD who are exon 45 skipping amenable. We plan to submit a CTA/IND application for ENTR-601-45 in the fourth quarter of 2024.

On November 7, 2023, we announced the selection of a third clinical candidate within our Duchenne franchise, ENTR-601-50, for the potential treatment of people living with DMD who are exon 50 skipping amenable. The selection of ENTR-601-50 is based onin vivo preclinical data that demonstrated robust exon 50 skipping across cardiac and skeletal muscle groups. We plan to submit a CTA/IND application for ENTR-601-50 in 2025.

Beyond exploring exon 44, exon 45 and exon 50 skipping amenable candidates, we have also launched research efforts to develop EEV-PMO for exon 51 skipping amenable populations. The exon 51 skipping amenable population is the largest single Duchenne sub-population, representing approximately 14% of patients. Our goal is to identify a therapeutic candidate for exon 51 skipping amenable patients in 2024.

We are supporting the development of VX-670, in partnership with Vertex for patients with DM1. DM1 is a rare disease caused by a mutation driven alteration of normal RNA structure manifesting as an increase in the number of CTG triplet repeats found in the 3’ non-coding region of the DM1 protein kinase (DMPK) gene. The resulting transcripts, which contain an expanded CUG tract, aggregate in discrete foci in the nuclei of DM patient cells. The excessive number of CUG repeats impart toxic activity, referred to as a toxic gain-of-function. Multiple key proteins are misprocessed, and this contributes to the multi-systemic nature of the disease, which includes generalized limb weakness, respiratory muscle impairment, cardiac abnormalities, fatigue, gastrointestinal complications, cataracts, incontinence and excessive daytime sleepiness. DM1 is commonly estimated to affect approximately 110,000 people in the United States and Europe. VX-670 is intended to address the underlying cause of thedisease by targeting the extra CUG triplet repeats responsible for the downstream misprocessing of proteins important to cell growth, metabolism and function. VX-670 is designed to block the triplet repeats and correct the mis-splicing and aberrant expression of downstream transcripts in order to restore tissue function. Our preclinical studies have resulted inin vitro andin vivo data where we have observed splicing correction across multiple transcripts, durable DMPK mRNA knockdown, reduction of foci, rapid phenotypic correction, and tolerability in murine models of DM1 which exhibit expanded CTG and CUG repeats.

On January 7, 2024 Vertex announced authorization from the MHRA of a clinical trial application for VX-670 for patients with DM1 and initiation of a Phase 1/2 clinical trial in patients with DM1 in Canada and that it will initiate the study in the UK in the near-term. Vertex also noted that they submitted an IND application to the FDA for VX-670. The FDA requested additional information, which resulted in a clinical hold. Vertex is working to address the FDA's comments in order to initiate the study in the U.S.

Under the terms of the Vertex Agreement, we received $250 million from the Vertex Agreement comprised of an upfront payment of $223.7 million and an equity investment of $26.3 million in our common stock at $16.26 per share. We are eligible to receive up to $485 million for the successful achievement of certain research, development, regulatory and commercial milestones, and tiered royalties on potential future net sales for any products that may result from this collaboration. In October 2023, we disclosed achievement of a milestone pursuant to the Vertex Agreement related to preclinical IND-enabling GLP toxicology studies of VX-670 that triggered a $17.5 million milestone payment.

The Vertex Agreement includes a four-year global research collaboration whereby Entrada will continue to advance and receive payments for certain research activities related to VX-670, as well as additional DM1-related research activities. Vertex will be responsible for global development, manufacturing and commercialization of VX-670 and any additional programs stemming from Entrada’s DM1 research efforts.

We believe our EEV Platform has broad applicability across multiple neuromuscular diseases. In addition to DMD and DM1, we are leveraging this platform to explore EEV-associated oligonucleotides for the potential treatment of Pompe disease. Pompe disease is a rare, autosomal recessive lysosomal storage disease caused by a mutation in the gene that encodes for glucosidase alpha acid (GAA), which results in an absence or deficiency of GAA protein that is essential to the breakdown of complex sugar, glycogen. Excess glycogen in the muscle cell leads to tissue damage and loss of function. Pompe disease is commonly estimated to affect between 5,000 and 10,000 patients in the aggregate in the United States and Europe; however, the advent of newborn screening suggests the disease is underdiagnosed. Our Pompe disease program focuses on the development of a potentially disease-modifying treatment by targeting and degrading both the mRNA-encoding glycogen synthetase 1 (GYS1) protein required for the synthesis of glycogen which powers in muscle cells and by enhancing the body's ability to degrade glycogen directly. Our preclinical data has shown superior and dose-dependent EEV-PMO knockdown of GYS1 gene expression (approximately 95%) and protein production in skeletal and cardiac muscles versus PMO alone. Further, protein level reductions were durable to eight weeks post IV dose of 13.5 mg/kg EEV-PMO. Preclinical development is ongoing.

Beyond Neuromuscular Disease

Ocular Disease

High unmet need continues to exist across a wide range of ocular diseases including macular dystrophies, photoreceptor diseases, optic neuropathies, among others. Many of these are of genetic origin and potentially addressable via RNA based therapeutics including exon skipping approaches. Despite the benefits of both local delivery and immune privilege many of these diseases have proven to be difficult to treat, as evidenced by a number of clinical failures. The retina is a complex structure consisting of multiple layers of tissue and a range of different cell types. A consistent challenge for developers has been the distribution and uptake of therapeutic candidates broadly, throughout the various layers and cell types across the retina. We believe our EEV-therapeutics can more effectively engage disease specific targets within these tissue layers opening the door to the development of new therapeutic candidates. As such we have preclinical efforts ongoing with the goal of further elucidating the benefits of EEV conjugation. Our lead ocular program targets an indication which results in blindness and affects several thousand exon skipping amenable patients in the United States alone. There are no approved therapies that address the underlying cause of disease. Lead optimization work on both novel oligonucleotide sequences and fit for purpose EEVs is on-going.

Additional Preclinical Development and Discovery Programs

We are leveraging the modularity of our EEV Platform to develop opportunities as diverse as EEV-lipid nanoparticle (EEV-LNP) enabled CRISPR-Cas delivery for gene editing, EEV-LNP based delivery of mRNA, EEV-antibody and peptide drug conjugates, EEV-therapeutic opportunities for central nervous system (CNS) and peripheral nervous system (PNS) disorders, EEV-antibody oligonucleotide conjugates for enhanced tissue tropism in immunology and oncology, as well as for blood brain barrier carriage, EEV-therapeutics with enhanced distribution in retinal tissue for ocular indications, and novel ERT therapies. We regularly explore strategic opportunities to develop potential therapies for patients with devastating diseases.

Our Strategy

We aim to transform the lives of patients by establishing EEV therapeutics as a new class of medicines and we aim to become the world’s foremost intracellular therapeutics company. To achieve this, the key pillars of our strategy include:

•Rapidly advance EEV-PMO therapeutic candidates into clinical development in patients with neuromuscular disease. Our DMD franchise is comprised of exon-skipping EEV-PMO candidates that aim to restore functional dystrophin production, for which we have initiated our first clinical trial in the United Kingdom.

We have a four-year research and development collaboration with Vertex. A global phase 1/2 trial in DM1 patients has been initiated for the lead program, VX-670, and the teams continue to explore the potential for additional EEV-based therapeutic candidates for the potential treatment of DM1. We believe that potential technical success in DM1, which involves correcting for a toxic gain of function, could be broadly applicable within and beyond neuromuscular diseases. We are leveraging the proceeds received from our partnership to invest heavily in additional DMD and non-neuromuscular candidate identification and development.

•Leverage the modularity of our platform along with our growing capabilities in genetic medicine and protein design to advance a broad development portfolio of therapeutic candidates across multiple devastating diseases. We believe our modular platform and expanded capabilities can enable us to advance therapeutic candidates for the treatment of additional neuromuscular and non-neuromuscular diseases for which the biophysical properties, therapeutic approaches, and development strategies involve regulating gene and protein expression. Weare experimenting with combinations of different platform elements to enhance the therapeutic index and half-life of potential candidates and to enable new mechanisms of action.

•Selectively evaluate strategic partnerships to maximize the therapeutic potential of our platform and programs. We aim to improve patients’ lives and plan to enable strategic partnerships with the goal of expanding our therapeutic footprint, and to accelerate the development of certain programs.

Our Team and Culture

Entrada was founded based on exciting science that has the potential to transform the treatment of serious diseases. We are a dedicated team of experts and leaders in both disease biology and therapeutic development, working with urgency to make positive differences in the lives of patients and their families. We have a shared passion for involving patients and caregivers so that we may better understand the patient experience in order to develop therapies that more effectively reflect their perspectives and priorities.

Our management team brings a depth of experience and knowledge base in research, drug discovery and development and commercialization. The team is led by Dipal Doshi, our Chief Executive Officer, who brings over 20 years of leadership experience within life sciences companies; Nathan Dowden, our President and Chief Operating Officer, who has three decades of experience leading corporate strategy, portfolio management, business planning and operations; Natarajan Sethuraman, Ph.D., our Chief Scientific Officer, who is an expert in large molecule therapeutic development and delivery platforms with over 30 years of experience across pharmaceutical and biotechnology companies; Kory Wentworth, our Chief Financial Officer, who has over 20 years of public accounting and global biopharmaceutical experience, andour General Counsel, Jared Cohen Ph.D., J.D., who has 20 years of both external and in-house experience at a range of mature and early stage biopharmaceutical companies. Our leadership team also includes Karla MacDonald, our Chief Corporate Affairs Officer, and Kerry Robert, M.S., our Senior Vice President, People, who has 15 years of experience building leading talent organizations in biotechnology and technology companies. Entrada appointed Kevin Healy, PhD, as Senior Vice President of Regulatory Affairs in February 2024. He has extensive expertise in the development and commercialization of therapies for serious and rare diseases and has led or participated in more than 30 formal meetings with the FDA, EMA, and other global health authorities.

As of March 6, 2024, our organization was comprised of 159 talented individuals with significant experience across discovery, preclinical research, manufacturing, clinical development and operations. We are supported by leading scientific and clinical experts in the fields of peptide chemistry, oligonucleotide and protein optimization, disease specific pathophysiology and clinical development.

Our Platform

Biology of Intracellular Trafficking

Each person’s genetic material, or genome, consists of DNA in sequences of genetic code called genes. Many diseases, including rare genetic diseases, immune-mediated disorders and cancers, are caused by a mutation in an individual’s DNA sequence, as compared to a healthy individual. These mutations can be in a single gene, and result in monogenic disorders, or in multiple genes. This genetic dysregulation can be inherited or can be caused by damage to the DNA. In each case, a mutation results in a change in the information that DNA provides to the cell’s protein manufacturing and processing functions, which in turn result in either a lack of useful protein, an excess of toxic protein, or a dysregulation of cell signaling mechanisms. These changes manifest in pathological dysfunction at the cellular, tissue, organ and potentially systemic level.

As pathological dysfunction occurs inside the cell, intracellular therapeutics are designed to correct disease-causing dysfunction at either the level of DNA, RNA, or protein. Therapeutic modalities which prevent or enhance protein production include small molecules, viral gene therapies and oligonucleotide therapeutics, including anti-sense oligonucleotides (ASOs) and small interfering RNAs (siRNAs). Therapeutic modalities which target aberrant proteins include small molecules, enzymes, antibodies and peptides.

Despite significant advances in understanding disease drivers, obstacles to effective treatment remain, in part because approximately 75% of all disease-causing targets are located inside of cells. Small molecules can permeate cell membranes but tend to be rapidly cleared by the body before they reach the intended tissue and can be associated with off-target effects. These limitations often necessitate high therapeutic doses and can be associated with less-than-optimal therapeutic activity.

On the other hand, biological therapeutics are highly targeted and potent but are limited in their ability to reach intracellular targets of interest. The first challenge is to get biological therapeutics, such as proteins and nucleic acids, through the phospholipid bilayer. Proteins and nucleic acids can be internalized through endocytosis, a natural process by which substances are brought into the cell. Once endocytosis begins, the cell membrane folds around the biological therapeutic and internalizes it, fusing with it and trapping it in a structure called the early endosome. The early endosome serves as a sorting vehicle, either returning its contents back to the cell membrane or transporting and slowly degrading them in the late endosome and, ultimately, in the lysosome.

The second challenge is achieving endosomal escape, wherein the biological therapeutic is released in functional form from the early endosome. Even when a therapeutic is successful in penetrating a cell, only about 1% of the drug will escape the early endosome to reach its intended intracellular targets. As a result, high doses of drug product are often needed to produce a therapeutic effect, which could potentially cause systemic dose-related toxicity. While scientific advances using lipid particles, viral vectors, antibodies and prior generations of cell-penetrating peptides to deliver biological therapeutics have been made, these vehicles are often relatively toxic, limited in their applicability and/or difficult to manufacture.

To effectively capitalize on both known biology and future discoveries, a better way of targeted intracellular delivery of therapeutics is needed. We believe we have discovered a potential solution.

Our Approach

An ideal therapeutic platform enables the efficient intracellular delivery of highly targeted and potent therapeutics throughout the body. The cornerstone of our platform, our proprietary EEVs are based upon small cyclic peptides of approximately 10 amino acid residues or fewer. EEVs bind with low affinity, at normal serum pH levels, directly to the phospholipid bilayer of all cells and trigger the natural process of endocytosis. EEVs are chemically conjugated to a wide range of specific and potent biological therapeutics, including, for example, small snippets of therapeutic RNA (ASOs), antibodies and large enzymes, to create EEV therapeutic candidates.

Once the EEV-conjugated material binds to the phospholipid bilayer, the cell engulfs the conjugate and brings it inside. EEVs are designed to enable cellular uptake into every type of tissue in the body. In addition to the potential for broad cellular distribution, we have demonstrated that certain EEV chemistries bias toward specific cell types and we believe EEVs can also, if needed, be tailored to specific cell types or tissues through the conjugation of high affinity cell-receptor antibodies, wherein the picomolar to nanomolar level receptor binding affinity would be expected to easily out-compete the low affinity phospholipid binding activity of the EEV. We leverage a variety of organelle targeting moieties to ensure that, where necessary, the therapeutic reaches the right sub-compartment inside the cell.

In our preclinical studies, we have observed, based on mass balance analysis, that greater than 90% of EEV-conjugated material is taken up by the tissues of the body. Once inside the cell, these studies indicate that the EEV-conjugated material rapidly escapes from the early endosome. Because of the low-pH conditions in the early endosome, the binding affinity of the EEV to the inner endosome wall increases, resulting in the successful formation and budding of unstable vesicles which then collapse and release their contents into the cell cytosol. In our preclinical studies, we observed that approximately 50% of the EEV-conjugated material escaped the endosome to reach the intracellular disease target as compared to the <2% observed in prior studies of current biologics. While these preclinical studies were not designed as head-to-head comparisons to current biologics, these data generally compare favorably to historical published data regarding the percentage, of current biologics that have been observed to reach their designed intracellular disease target.

Key attributes of our EEV Platform include:

•Serum stability and extended half-life: The cyclic structure of EEVs is designed to limit protease-mediated degradation, resulting in increased stability and extended half-life. In contrast, linear cell-penetrating peptides are rapidly degraded in human serum.

•Broad biodistribution: EEVs target phospholipid bilayers and can therefore potentially be delivered to any cell in the body, regardless of route of administration. Additionally, and importantly, cyclization confers unique biophysiochemical properties to EEVs, optimally positioning side chains for membrane association and enabling the use of fewer positively charged cationic residues, which we believe could reduce potential toxicities of EEVs relative to linear peptides which rely on chemistries with a high positive charge.

•Active uptake and drug release: EEVs bind to membrane phospholipids but not proteoglycans and thus avoid being trapped in the cell membrane. The low affinity binding to the cell surface triggers endocytosis and we have observed that 90% of the EEV-conjugated material was taken up in tissue in our preclinical studies. The low pH enhanced affinity of EEVs triggers the budding of vesicles from the early endosome and we have observed the subsequent release of approximately 50% of this material into the cytosol in our preclinical studies.

We have developed a proprietary library of EEVs to enable the intracellular engagement of therapeutics against previously inaccessible and undruggable disease-causing targets. EEVs are broadly distributed, highly targeted, designed to have a wide therapeutic index and can be chronically dosed.

Key advantages of our platform include:

•Broad potential therapeutic index: Our EEV Platform is designed to allow specific biological therapeutics to engage targets across every cell in the body. In our preclinical studies, we observed that approximately 50% of the EEV-conjugated material escaped the endosome to reach the intracellular disease target as compared to the <2% observed in prior studies of current biologics. While these preclinical studies were not designed as head-to-head comparisons to current biologics, these data generally compare favorably to historical published data regarding the percentage of current biologics that have been observed to reach their designed intracellular disease target. We therefore believe that our EEV Platform can enable greater target exposure with an unconjugated therapeutic and similar dose regimen.

•Potential across multiple modalities: Our EEV Platform is designed to enable the development of intracellular therapeutic candidates that modulate, inhibit, degrade or replace an intracellular target to correct the underlying disease pathophysiology. In our preclinical studies of EEVs, we observed intracellular uptake of unique therapeutic candidates ranging in size from 1 kDa to 600 kDa, including oligonucleotides, antibodies and larger multimeric proteins. Unlike viral vectors or certain lipids and nanoparticle constructs, EEVs do not appear to be hampered by “packaging limits”. For example, adeno-associated viruses constructs are limited to 5 kb in length, dramatically restricting both the size of genes and complexity of regulatory sequences that can be delivered. Importantly, our preclinical studies support the concept of modularity in that we can use similar EEV structures across the portfolio. EEVs are then further optimized to the specific application of interest. For example, in our preclinical discovery efforts, EEV-modified LNP (EEV-LNP) significantly enhanced the efficiency of mRNA delivery and gene editing compared to unconjugated LNP. Each program advanced contributes to a foundation upon which our development portfolio can continue to expand.

•Potential across tissue types: Our EEV Platform is not limited to a particular tissue type. Because every cell in the human body is surrounded by a phospholipid bilayer, this enables the systemic delivery of potential therapeutic candidates for a wide range of diseases. We have seen potentially clinically relevant uptake of EEV-conjugates across a wide range of organs, tissue and cell types, including skeletal and cardiac muscle, monocytes and macrophages, ocular tissues such as the retina and tissues found in the central and peripheral nervous system. We have also shown in preclinical studies that, if need be, we can target our EEV-conjugated nucleotides by adding tissue-targeting moieties or organelle-targeting sequences, including, for example, nucleus, mitochondria and peroxisome.

•Multiple delivery routes: In our preclinical studies, we have generated functional outcomes systemically using IV, and SQ injections. Preclinical studies have also demonstrated what we believe to be therapeutically relevant concentrations of product uptake in the CNS and the retina via IT and IVT administration respectively.

•Modular approach that enables efficient expansion into multiple therapeutic areas: We have a wide variety of programs in discovery and preclinical development, including nucleic acid and protein based therapies in neuromuscular disease and beyond. The EEV Platform facilitates the effectiveness of the modality, which in turn produces the translational output.

•Translatability, as the mechanisms of cell entry and endosomal escape are thought to be conserved across species. Acute and chronic toxicology studies in several programs have demonstrated the potential to deliver clinically-relevant doses in multiple animal species with favorable tolerability.

•A simple and scalable construct designed to translate from preclinical to clinical development as EEVs have been manufactured efficiently at both clinical and commercial scale.

•The size of EEVs implies that they are unlikely to be presented on the surface of immune cells, and therefore we believe the risk of immunogenicity may be low and limited to the conjugate of the EEV therapeutic candidate.

Due to these significant advantages associated with the EEV platform, we focused on applying our platform in the following areas:

•Oligonucleotide programs: In our neuromuscular programs, we leverage EEV-enabled oligonucleotides. EEV-ASOs are highly programmable and can upregulate or downregulate gene expression. We are developing a DMD franchise, with our most advanced program ENTR-601-44 progressing in clinical trials. In patients with DMD, there are mutations in or deletions of regions in the genetic code responsible for dystrophin production. These mutations or deletions result in the creation of incomplete RNA sequences, which fail to create functional dystrophin. By using our EEV-PMOs, we have demonstrated in animal models that we can skip mutated sequences, allowing the cell to create functional dystrophin. Other programs such as VX-670 and our work on GYS1 aim to downregulate gene expression either by using steric blocking of the relevant coding region of the mRNA to prevent translation or by utilizing exon skipping to introduce a premature stop codon and the initiation of nonsense mediated degradation. The backbone EEV and oligonucleotide chemistries are the same across the various applications, and if successful, we anticipate that we can leverage our approach across a wide range of diseases by simply coding the sequence needed to impact gene expression. We also continue to expand the utilization of EEV-PMO based exon-skipping as we advance our efforts in ocular disease.

•Antibody and peptide based programs: To widen the therapeutic index, we believe the endosomal escape enhancing efficiency of an EEV can be combined with the enhanced circulating half-life and tissue tropism associated with receptor mediated binding to more selectively target or avoid specific cell types and efficiently deliver a variety of active payloads. Preclinical studies have demonstrated intracellular delivery of a variety of full and partial domain antibodies and we have observed target engagement and a meaningful modulation of downstream signaling.

•Enzyme/protein related programs: EEVs can be linked to an enzyme critical to maintaining specific steps in a cell’s metabolic processes. Patients lacking a given enzyme will fail to produce proteins needed to maintain the viability of cells in the body or will suffer a buildup of toxic byproducts, either of which can result in disease and potentially death. We have generated a number of EEV-enzyme conjugates, including ENTR-501 for MNGIE, a fatal mitochondrial disease, for which we have completed IND-enabling studies. NHP pharmacokinetic and acute and chronic toxicology studies indicated both a long circulating half-life and a favorable tolerability profile, which may serve as a foundation upon which our ERT programs can later build.

•Combination programs: We are exploring the use of EEVs in combination with additional carriers such as LNP as a novel non-viral vector delivery system for mRNA and gene editing. We are working with combinations of active moieties and carriers to optimize therapeutic index by simultaneously engaging multiple intracellular and extracellular targets.

Ultimately, we believe that the significant increase in intracellular target exposure enabled by EEV conjugation has the potential to translate into substantial improvements to the efficacy, safety, tolerability, manufacturability and cost of future medicines.

Our Development Portfolio

We are creating a diverse and expanding development portfolio of RNA-, antibody- and enzyme-based programs. Included in this development portfolio are several of our oligonucleotide programs for the treatment of multiple neuromuscular diseases, including DMD, DM1 and additional preclinical and discovery programs. In addition, we are exploring oligonucleotide opportunities in neuromuscular, immunological, ocular and metabolic diseases, among others. Research efforts include enzyme replacement therapies, targeting moieties and gene editing. The chart below represents a summary of our initial development programs, including those that are being developed by us and the VX-670 program which is Vertex partnered.

Duchenne Muscular Dystrophy

In neuromuscular disease, we are initially focused on the development of disease-modifying treatments for DMD. DMD is a monogenic X-linked disease caused by mutations in the DMD gene, which encodes for the protein dystrophin. We estimate that DMD occurs in approximately one in every 3,500 to 5,000 live male births and that the patient population is approximately 30,000 patients in the aggregate in the United States and Europe. Approximately 80% of patients have mutations amenable to exon skipping in the nucleus. We are developing therapeutic candidates to address the genetic basis, at the exon-specific level, of DMD. EEV oligonucleotides are designed to promote the skipping of exon mutations associated with DMD, enabling muscle cells to create a functional dystrophin at a level that we believe may slow, stop or even reverse DMD progression. Our most advanced programs include ENTR-601-44, for the 7.6% of patients with DMD that are exon 44 skipping amenable, ENTR-601-45 for the 8.1% of DMD patients who are exon 45 skipping amenable and ENTR-601-50 for the 3.8% of patients with DMD that are exon 50 skipping amenable. There is a robust data set supporting the development of these programs.

On July 24, 2023, we received authorization from the MHRA for our Phase 1 clinical trial in healthy volunteers, ENTR-601-44-101. The Phase 1 clinical trial's primary objective is to evaluate the safety and tolerability of a single dose of ENTR-601-44 in healthy volunteers, with a target enrollment of approximately 40 participants. The trial will also evaluate pharmacokinetics and target engagement as measured by exon skipping in the skeletal muscle, bearing the Company's recentin vitro data showed that exon skipping was approximately 10-40x higher in dystrophic muscle compared to healthy muscle, suggesting that data from healthy normal volunteers may substantially underestimate potential potency. On March 13, 2024, we announced that the first, second and third cohorts of participants had been successfully dosed and we expect to report data from the Phase 1 clinical trial in the second half of 2024. The data from this trial will inform our global clinical development strategy, and if favorable, support regulatory filings to open a global multiple ascending dose (MAD) Phase 2 trial in Duchenne patients who are exon 44 skipping amenable in the fourth quarter of 2024. It is expected that countries will be included in the trial on a rolling basis, as dependent on discussions with individual regulators.

On December 16, 2022, the U.S. FDA Office of Orphan Products Development (OOPD) granted orphan drug designation for ENTR-601-44 for the treatment of DMD. The FDA's OOPD grants orphan drug status to support drug candidates in development for underserved patient populations or rare disorders that affect fewer than 200,000 people in the United States. Orphan drug designation provides certain benefits, including market exclusivity upon FDA approval, exemption of FDA application fees, and tax credits for qualified clinical trials.

On January 9, 2023, we announced the selection of a second clinical candidate within our Duchenne franchise, ENTR-601-45 for the potential treatment of people living with DMD who are exon 45 skipping amenable. We plan to submit regulatory applications in the fourth quarter of 2024 for the global Phase 2 clinical development of ENTR-601-45 in Duchenne patients who are exon 45 skipping amenable.

On November 7, 2023, we announced the selection of a third clinical candidate within our Duchenne franchise, ENTR-601-50 for the potential treatment of people living with DMD who are exon 50 skipping amenable. The selection of ENTR-501-50 is based onin vivo preclinical data that demonstrated robust exon 50 skipping across cardiac and skeletal muscle groups. We plan to submit regulatory applications to initiate a global Phase 2 trial in Duchenne patients who are exon 50 skipping amendable in 2025.

Beyond exploring exon 44, exon 45 and exon 50 skipping amenable candidates, we have also launched research efforts to develop EEV-PMO for exon 51 skipping amenable populations. The exon 51 skipping amenable population is the largest single Duchenne sub-population, representing approximately 14% of patients. Our goal is to identify a therapeutic candidate for exon 51 skipping amenable patients in 2024.

DMD Background and Market Opportunity

DMD, also commonly referred to as Duchenne, is a monogenic, X-linked disease caused by mutations in the DMD gene, which encodes for the dystrophin protein. Dystrophin is essential to maintaining the structural integrity and normal function of muscle cells for walking, breathing and cardiac function. In patients with Duchenne, mutations in the DMD gene can lead to certain exons being misread, resulting in a failure to produce sufficient functional dystrophin. The reduction or absence of functional dystrophin leads to damage to muscle cell membranes, resulting in muscle cell death and progressive loss of muscle function.

The symptoms of Duchenne typically manifest in the first few years of life. Patients experience progressive muscle weakness and muscle wasting and have difficulty standing up, climbing stairs, running, breathing and performing daily functions. As the disease progresses, the severity of damage to skeletal and cardiac muscles results in most patients experiencing total loss of ambulation in the pre-teenage or early teenage years. Progressive loss of upper extremity function is often observed in the mid-to-late teens followed by paralysis, respiratory and/or cardiac failure, resulting in early mortality in the third or fourth decade of life.

We estimate that DMD occurs in approximately one in every 3,500 to 5,000 patients and that the patient population is approximately 30,000 patients in the aggregate in the United States and Europe. Approximately 80% of patients have mutations amenable to exon skipping in the nucleus. Approximately 43% of patients with Duchenne have mutations amenable to exon skipping of exons 44, 45, 50, 51 and 53, as illustrated in the figure below.

Corticosteroids are the current standard of care. However, chronic use of corticosteroids, particularly in pediatric populations, is challenging due to side effects including growth impairment, immune suppression, obesity and other endocrine-related disorders. There are four FDA-approved PMO-based oligonucleotide skipping therapies, each addressing a specific mutation: casimersen (exon 45), eteplirsen (exon 51), golodirsen (exon 53) and viltolarsen (exon 53). These products have all been approved using the accelerated approval pathway on the basis of dystrophin production. Currently approved exon skipping therapeutics have demonstrated a modest improvement in dystrophin levels ranging from approximately 1-6%. However, the FDA-approved labels for all four drugs state that continued approval may be contingent upon the verification of a clinical benefit in confirmatory clinical trials. None of the products are approved by the European Medicines Agency (EMA) due to insufficient evidence of clinical benefit. A fifth drug, ataluren, was conditionally approved outside of the United States in certain territories for nonsense mutations in ambulatory patients with DMD aged five years and older. However the EMA has recently decided not to renew the drugs marketing authorization and as a result ataluren is expected to be removed from the market. Finally, these therapies require weekly intravenous infusions which is suboptimal from a patient perspective. In summary, each of these approved products also seeks to address DMD through exon skipping, but to date, the clinical benefits of these products have not been confirmed.

Our Solution

Our DMD program is designed to address the genetic basis of Duchenne by promoting the skipping of specific DMD exons in the nucleus, allowing muscle cells to create a functional dystrophin protein. Our EEV Platform is designed to enable high cellular uptake and robust cytosolic delivery of EEV therapeutic candidates, resulting in a greater amount of the oligonucleotide being able to reach its intended target in the nucleus. Based on preclinical data, we have shown that our proprietary oligonucleotide is then able to promote enhanced exon skipping and dystrophin production.

In preclinical models, we have observed that conjugation of an oligonucleotide to our EEV results in multi-fold greater exon skipping and dystrophin production than the oligonucleotide alone, with such results indicating dystrophin production comparable to wild-type levels in certain tissues. We have observed substantial improvement in dystrophin production in both skeletal and cardiac muscle, as well as uniform dystrophin production within tissues that we believe may be attributable to the unique mechanism of action of our EEV Platform and the broad biodistribution of our oligonucleotide conjugates. We have observed deep and uniform penetration of EEV-PMOs as compared to unconjugated oligonucleotides in our preclinical models, as illustrated below.

Importantly, we believe an increased level of dystrophin production in the heart may translate to improved cardiac function in patients with DMD.

Our preclinical data have demonstrated 50% to 100% correction of exon skipping in the D2-mdx model, which mimics human disease, and in a human dystrophin mouse model which enables us to evaluate our lead sequence directly. In an initial NHP model, we have observed almost 90% target exon skipping in skeletal muscles. We have generated promisingin vivo data in cardiac and skeletal muscles (including the diaphragm) across a range of disease and wild-type models (both murine and NHP). We believe the observed increase in dystrophin production is sufficient to protect muscle from progressive functional decline in treated mice and the improvement in functional outcomes versus controls observed in the D2-mdx model supports this belief.

Summary of Preclinical Data

Our early data in mouse and NHP models have been consistent and robust. We have observed substantial exon skipping and dystrophin production in various tissues of mdx mice. Themdx mouse is the canonical model used in DMD research and carries a spontaneous nonsense mutation in exon 23 of the DMD gene. Although this does not allow for the testing of oligonucleotides specific to human mutations, it does enable measurement of tissue concentration of oligonucleotides, exon 23 skipping levels and the corresponding dystrophin production. This allowed us to extrapolate anticipated dystrophin production from exon-skipping observations as we move to NHP models. We were also able to show in both single-dose and multiple-dose experiments that the EEV-PMOs has greater activity than unconjugated PMOs. Similarly, EEV-PMOs had greater activity than alternative cell-penetrating peptide conjugates in our preclinical studies. We also observed corresponding and significant improvements in functional outcomes as measured in the exon 23 specific D2-mdx mouse. In particular, we observed meaningful tissue uptake and exon skipping, ranging from approximately 60% to 95% depending on the tissue. In this model, EEV-PMO treated tissues have substantial restoration of both dystrophin and alpha sarcoglycan. Importantly, we see an accumulation of exon skipping and dystrophin production after subsequent doses of EEV-PMO in the D2-mdxmouse spaced 6 weeks apart, and WT levels of dystophin positive fibers. Our preclinical studies have also demonstrated reductions in serum CK to wild-type levels in D2-mdx model. Serum CK is a commonly-used biomarker of systemic muscle breakdown. Correction of CK is believed to be a strong indicator of pharmacodynamic activity and a marker of muscle integrity restoration. We observed extended half-life and high levels (almost 90% in the biceps) of exon skipping in a NHP with ENTR-601-44. Finally, we have shown, in the same model, exon skipping levels of over 90% with ENTR-601-45 and more importantly an ability to optimize the PMO conjugate and deliver a multi-fold improvement in exon skipping over the commercially available sequence, even when that sequence is conjugated to an EEV.

In the data below, unless otherwise noted, we used reverse transcription-polymerase chain reaction to assess exon skipping and Western Blot to assess dystrophin production. Our preclinical studies have demonstrated durable dystrophin production over a period of up to eight weeks, and accumulation of dystrophin after doses spaced six weeks apart suggesting the possibility of infrequent dosing. Immunohistochemistry and morphometric analysis confirm that the protein is broadly distributed across tissues, which is necessary if the muscle is to maintain function.

For each of our preclinical studies that were powered for statistical significance, we have so indicated with the p or p-values presented. In the description of our preclinical studies below and elsewhere in this Annual Report, p or p-values represent the probability that random chance caused the result. For instance, a p-value of 0.001 means that there is a 0.1% probability that the difference between the placebo group and the treatment group is purely due to random chance. A p-value of less than or equal to 0.05 is a commonly used threshold for identifying statistically significant outcomes.

mdx Mouse Dystrophin Distribution Analyzed via Immunofluorescence After Four Injections of EEV-PMO at 10 mg/kg

In the experiment above, mdx mice were injected with weekly doses of either saline, unconjugated exon 23 skipping PMO or an EEV conjugated to the same exon 23 skipping PMO over the course of four weeks. Samples were taken one week after the fourth dose. The EEV-PMO-DMD substantially increased dystrophin production and accumulation in the heart, with approximately 40% of the cardiac tissue staining positive for dystrophin (in red). This compares favorably to the PMO alone, where at even double the dose virtually no dystrophin can be seen. Endothelial cells are stained green, and as shown in the image, dystrophin can be observed distributing broadly and deep into the cardiac tissue. We believe this experiment suggests that at low doses an EEV oligonucleotide has the potential to substantially improve on treatment with unconjugated oligonucleotides. We also believe these heart results suggest the possibility that EEV-PMOs may address cardiomyopathy in patients with DMD, which is a major complication and leading cause of death associated with the disease. We believe this could therefore potentially improve survival rates.

This improvement in dystrophin production at 10 mg/kg is also associated with an observed improvement in measured serum creatin kinase (CK) levels. Serum CK is a commonly-used biomarker for systemic muscle breakdown. CK is released from muscles with damaged and porous sarcolemma, which, in the case of DMD, is due to a lack of functional dystrophin. Normalization of serum CK indicates broad correction of dystrophin and protection of the sarcolemma throughout the body, which can further imply a potential restoration of function.

Normalization of Serum CK Levels in mdx and Wild-Type (BL10) Mice

In the experiment abovemdx mice were injected with weekly doses of either saline, unconjugated exon 23 skipping PMO or an EEV conjugated to the same exon 23 skipping PMO over the course of four weeks. Samples were taken one week after the fourth dose.

We have also observed that tissue concentration of EEV-PMO in the cell correlates with the level of exon skipping, which correlates with dystrophin production.

High Levels of Exon 23 Skipping and Tissue Concentration Observed in Various Muscle Groups at Three Different Doses of EEV-PMO in mdx Mice

In themdx mouse model illustrated above, exon skipping and tissue concentration in various muscle groups have been quantified one week after a single 20, 30 or 40 mg/kg intravenous (IV) dose of an EEV conjugate to an exon 23 skipping PMO inmdx mice. A dose-dependent effect was seen, both with respect to tissue concentrations and exon 23 skipping levels, which ranged from approximately 80%-100% at the highest IV dose of 40 mg/kg, depending on the tissue sampled. These dose-dependent tissue concentrations and the correlation with exon skipping suggest active target engagement in heart, diaphragm and other skeletal muscles.

High Levels of Exon 23 Skipping and Dystrophin Correction Observed up to 8 Weeks After a Single IV Dose of EEV-PMO in mdx Mice

Following dose-ranging experiments, exon 23 skipping and dystrophin production in various muscle groups were quantified one week, two weeks, four weeks and eight weeks after a single IV dosage of 40 mg/kg in mdx mice. We selected the highest dose based on the magnitude of exon skipping observed.

Normalization of Serum CK Levels in mdx and Wild-Type (BL10) Mice

In this experiment, untreated wild-type (BL10) mice were compared tomdx mice treated with EEV-PMO andmdx mice treated with phosphate-buffered saline (PBS). Serum CK frommdx mice was analyzed one week after a single 40 mg/kg IV dose of EEV-PMO skipping exon 23 or of PBS. Treatment with EEV-PMO normalized serum CK levels in themdx mice, suggesting restoration of muscle integrity. In contrast, no significant correction of serum CK was seen in the PBS control arm.

EEV-PMO Significantly Improved Exon 23 Skipping After 3 Days in mdx Mice as Compared to R6-PMO

To compare the exon 23 skipping of an EEV against an alternative published linear peptide, we synthesized a 6 arginine (R6) cell-penetrating peptide and conjugated it to the exon 23 skipping oligonucleotide. We then compared the activity of this molecule to EEV-PMO, by conjugating the same oligonucleotide to one of our EEVs. After a single 40 mg/kg IV dose of the EEV-PMO or the R6-PMO, the EEV-PMO exhibited profound effects, with near complete exon skipping in the diaphragm and the quadriceps and approximately 60% exon skipping in the heart. The R6-PMO results were very limited in the skeletal muscle and virtually no pharmacodynamic effects were seen in the heart.

Superior Correction of Exon 23 Skipping in the D2-mdx Model Versus Unconjugated PMO

We have employed a methodical and robust approach to candidate qualification by generating data in the canonicalmdx mouse, as well as in a mouse model with a more severe phenotype known as the D2-mdx mouse. While the approach remains focused on exon 23 skipping, the D2-mdx mouse model more closely represents human disease as these animals develop more inflammation, fibrosis and exhibit less muscle regeneration over time when compared to themdx model. In the study above, we compare exon skipping in the quadriceps, diaphragm and heart as generated by either the EEV-PMO skipping exon 23 or the PMO alone skipping exon 23. The lack of response from unconjugated PMO illustrates the difficulty in generating pharmacodynamic responses in the D2-mdx model, and further reinforces the importance of EEV conjugation. The animals were given a single 40 mg/kg IV dose of either the PMO or the EEV-PMO. We were able to demonstrate approximately 50% to 95% exon skipping from the mice dosed with EEV-PMO, depending on the tissue sampled.

Subsequent to the single dose study above, a separate repeat dose study was conducted as shown below. D2-mdx mice were treated with three IV doses at monthly intervals of either 20 mg/kg of a saline vehicle, PMO-23, or EEV-PMO-23 (n=6 per cohort). We compared exon skipping by one-step reverse transcription-polymerase chain reaction in the heart, diaphragm, tibialis anterior (TiA) and triceps as generated by either the EEV-PMO-23 skipping exon 23 or the PMO-23 alone skipping exon 23. We believe the significant difference in exon skipping observed between the EEV-PMO-23 and the PMO-23 in the D2-mdx model at a lower dose further reinforces the potential importance of EEV conjugation. We were able to demonstrate approximately 60% to over 95% exon skipping from the mice dosed with EEV-PMO-23 depending on the tissue sampled.

Superior Correction of Exon 23 Skipping at 22 Weeks Using an EEV-PMO in the D2-mdx Model Versus an Unconjugated PMO At 20 mg/kg

A durable CK response was observed in EEV-PMO-23 treated mice versus both vehicle and PMO-23 treated mice. In this experiment D2-mdx mice were treated with 4 monthly doses of either vehicle, 20 mg/kg PMO or 20 mg/kg PMO equivalent of EEV-PMO, and the data were collected 4 weeks after the last dose. No significant difference was seen between CK levels measured in wild type control mice and EEV-PMO-23 treated mice. We believe that this observation of reduced skeletal muscle breakdown resulted in improved functional outcomes for EEV-PMO-23 treated mice as evidenced by measurement of both wire hang time and a normalization of grip strength. In each case a significant difference (p<0.05 for wire hang time, p<0.001 for grip strength) between PMO-23 treated mice and EEV-PMO-23 treated mice was observed.

Repeat EEV-PMO-23 Treatment Normalized Serum CK Levels and Showed Significant Improvements in Muscle Function When Compared to PMO Alone After Four Monthly IV Doses in D2-mdx Mice

In the same experiment, dystrophin expression was assessed four weeks post last injection via immunofluorescent staining, shown in the representative gastrocnemius sections shown in bright green below. The untreated wild type mice and the EEV-PMO-23 treated D2-mdx mice show broad and appropriate dystrophin expression, while the D2-mdx mice treated with vehicle control and the D2-mdx animals treated with PMO-23 show little to no dystrophin expression.

D2-mdx Mouse Dystrophin Expression Analyzed via Immunofluorescence Is Enhanced After IV Administration of EEV-PMO Versus PMO Alone at 20 mg/kg

Muscle histopathology was also assessed four weeks after the last injection. The D2-mdx animals treated with vehicle control and those treated with PMO-23 show clear signs of fibrosis and muscle damage. This stands in contrast to healthy samples from both the normal, wild type mice and the EEV-PMO-23 treated D2-mdx mice shown on the far left and far right panels below.

Correction of D2-mdx Mouse Histopathology is Enhanced after IV Administration of EEV-PMO Versus PMO Alone at 20 mg/kg

In the same experiment we also observed similarly dramatic results when comparing the wild type, control and treated images of both dystrophin and histology in the heart, as shown below.

Repeat EEV-PMO-23 Treatment Corrected Dystrophin Expression and Pathology in the Heart After Four Monthly IV Doses in D2-mdx Mice

Further analysis of the previous experiment showed EEV-PMO treated tissues have almost normalized the level and the localization of both dystrophin and α-sarcoglycan. In striated muscle, sarcoglycans interact with dystrophin and other dystrophin-associated proteins to form the dystrophin-associated glycoprotein complex which protects the sarcolemma from contraction-induced injury. In the absence of dystrophin, α-sarcoglycan fails to correctly localize to the dystrophin-glycoprotein complex (DGC) causing weakening of the plasma membrane. Loss of dystrophin leads to loss in alpha-sarcoglycan in the D2-mdx tissue. In the figure below PMO treated mice had limited restoration of dystrophin as well as alpha-sarcoglycan. In contrast, EEV-PMO treated tissues have almost complete restoration of both dystrophin and alpha-sarcoglycan.

Repeat EEV-PMO-23 Treatment Resulted in Functional Restoration of Dystrophin and DGC Protein α-sarcoglycan After Four Monthly IV Doses in D2-mdx Mice

We also conducted a repeat dose efficacy study in D2. mdx (n=8) mice which received one, two, or three injections of vehicle or 80 mg/kg, EEV-PMO-23 once every six weeks. Muscle contractility, grip strength, and wire hang time were determined at 6, 12, and 18 weeks. Exon skipping, dystrophin protein, contractile function, and histological analysis were performed 6 weeks following administration of the last dose in each group.

Significant Increases of Exon 23 Skipping and Dystrophin Expression Following One, Two and Three Doses of 80 mg/k EEV-PMO-23 in Three Cohorts of D2-mdx Mice As Measured Six Weeks After Each Dose

In the figure above the exon skipping (as measured by ddPCR) and dystrophin levels (as measured by western blot were assessed in three different groups of D2-mdx mice. Each cohort was assessed six weeks after receiving the last dose. Not only were very high levels of both exon skipping and dystrophin production demonstrated, but both exon skipping and dystophin accumulated despite the six-week gap between doses. This is important as it supports our expected clinical dosing of no more that every six weeks (detailed below in the clinical trial description). In addition to the accumulation of dystrophin production, we also saw an increase in the percentage of dystrophin positive fibers, reaching wild type levels after only two doses as shown below.

Cumulative Increase In Dystrophin Expression After Repeat Doses of EEV-PMO-23 In D2-mdx Mice

This finding is important as a higher percentage of dystrophin positive fibers suggests a more robust, and potentially functional muscle.

Themdx mouse model, the most commonly used mouse model for DMD, carries a spontaneous nonsense mutation in exon 23 of the DMD gene. While this model has been useful to show proof-of-concept of the exon skipping approachin vivo, it does not allow for the testing of human-specific oligonucleotides. Consequently, we also used transgenic mice carrying an integrated copy of the full-length human DMD gene with an exon 44 skipping amenable mutation. While these mice do not exhibit the DMD phenotype, the model does allow for an assessment of exon skipping levels. The mice were given a single IV dose of an EEV conjugated to an exon 44 skipping PMO (a combination thereof defined as EEV-PMO-44) at 15 mg/kg and near 100% exon skipping was observed. This result is notable because the mice in this model have intact muscle cells, which have historically been more difficult for therapeutics to access than the damaged cells seen in amdx model. We believe that these robust exon skipping results suggest the potential for our EEV-PMO to expand into additional neuromuscular diseases in which uptake into intact muscle is crucial to demonstrating clinical activity.

Exon 44 Skipping Activity of EEV-PMO-44 as Compared to a R6 Conjugated Exon 44 Skipping PMO (Single IV Dose of 15 mg/kg in hDystrophin Mice)

We conjugated our lead exon 44 skipping sequence to an EEV from our candidate library, which we refer to as EEV-PMO-44, as mentioned above. Human dystrophic mice were IV dosed with 15 mg/kg of either EEV-PMO-44 or a R6 linear peptide conjugated to the same exon 44 skipping PMO. We observed exon skipping of between 60% to approximately 95% in the EEV-PMO-DMD-44 mice, compared to exon skipping of less than 20% in the R6-PMO-44-dosed mice.

ENTR-601-44

Following the exon 44 skipping preclinical work depicted above, we completed lead optimization work and initiated experiments for ENTR-601-44 in patient derived cells, humanized mice, and NHPs. The results of these studies are described below.

Dose-Dependent Levels of Exon Skipping and Significant Dystrophin Restoration Observed in Patient Derived Cells Treated With ENTR-601-44

In the experiment depicted above, patient derived cells were treated with the EEV-PMO-44, or ENTR-601-44. Dose-dependent exon 44 skipping and dystrophin protein restoration was observed (up to 100% and 43.7% respectively) in DMD patient-derived muscle cells treated with ENTR-601-44 compared with both untreated patient derived cells and

healthy cells. ENTR-601-44 was then studied in the humanized mouse model to assess uptake in tissue and exon skipping potential.

ENTR-601-44 Associated Dose (IV)-Dependent Tissue Exposure and Exon Skipping in a Transgenic Murine Model Carrying the Full-Length Human DMD Gene

In this experiment, the transgenic mice carrying an integrated copy of the full- length human DMD gene were administered ascending IV doses of ENTR-601-44 at various levels ranging from 10 mg/kg to 80 mg/kg. Exon skipping and tissue exposure were each assessed five days after dosing. We observed dose dependent levels of tissue exposure of up to 80% and exon skipping up to 100% with translationally relevant doses. At a single dose of 60 mg/kg, this exon skipping was sustained through twelve weeks as shown below.

Exon Skipping Sustained for up to 12 weeks after a single IV Administration of ENTR-601-44 at 60 mg/kg

Following the results from our transgenic mouse study, we initiated studies in NHPs.

Extended Circulating Half-Life for ENTR-601-44 Observed in Non-Human Primate Model

In the study depicted above, an IV dose of 30 mg/kg was administered over the course of one hour. The NHP was assessed at regular intervals, and an extended circulating half-life was observed. ENTR-601-44 was detectable in plasma up to 50 hours later. This pharmacokinetic profile suggests an opportunity for intended tissue exposure, target engagement and pharmacodynamic effects.

Meaningful Levels of Exon Skipping Observed After 7 Days in NHP after IV Administration of ENTR-601-44 at a dose of 30 mg/kg

Building upon this, in a separate experiment ENTR-601-44 further demonstrated robust exon 44 skipping in NHP biceps through 12 weeks following a single intravenous (IV) infusion, demonstrating durability of response. In this case two cohorts of NHPs were dosed at 35 mg/kg, and robust exon 44 skipping was observed in biceps in the ENTR-601-44 treated NHP (n=3 per cohort) for at least 12 weeks.

Robust Exon 44 Skipping Observed in Biceps in the ENTR-601-44 Treated NHPs For at Least 12 Weeks After a Single IV Dose of 35 mg/kg

Finally, we assessed the potential difference between exon skipping in healthy volunteers (see description of the ongoing single ascending dose trial below) and Duchenne patients. In thein vitro experiment depicted below healthy cells and patient derived cells were dosed with between 0.03 mmol to 3 mmol of ENTR-601-44. At each given dose exon skipping in patient cells was significantly higher (up to 40-fold).

Exon 44 Skipping in Healthy and Patient Myoblasts Treated with ENTR-601-44

In summary, a single 30 mg/kg IV dose of ENTR-601-44 resulted in meaningful levels of exon skipping in both skeletal and heart muscles and a single dose of 35 mg/kg resulted in sustained exon skipping for twelve weeks. These levels of exon skipping appear to correlate with the exon skipping observed with ENTR-601-44 in the transgenic mouse and the exon 23 skipping observed in the mdx and the D2-mdx mouse. We believe that these data, together with the correlation between exon skipping and dystrophin production in PPMO clinical trials, are encouraging as to the translational potential of ENTR-601-44. We further believe that these data provide support for the potential of the EEV Platform to address additional DMD populations.

Clinical Development Plan

On July 24, 2023, we received authorization from the MHRA for our Phase 1 clinical trial in healthy volunteers, ENTR-601-44-101. The Phase 1 clinical trial's primary objective is to evaluate the safety and tolerability of a single dose of ENTR-601-44 in healthy volunteers, with a target enrollment of approximately 40 participants. The trial will also evaluate pharmacokinetics and target engagement as measured by exon skipping in the skeletal muscle, bearing the Company's recentin vitro data showed that exon skipping was approximately 10-40x higher in dystrophic muscle compared to healthy muscle, suggesting that data from healthy normal volunteers may substantially underestimate potential potency.

On March 13, 2024, we announced that the first, second and third cohorts of participants had been successfully dosed and we expect to report data from the Phase 1 clinical trial in the second half of 2024. The data from this trial will inform our global clinical development strategy, and if favorable, support regulatory filings to open a global multiple ascending dose (MAD) Phase 2 trial in the fourth quarter of 2024. It is expected that countries will be included in the trial on a rolling basis, as dependent on discussions with individual regulators.

ENTR-601-45

ENTR-601-45 is the third novel clinical candidate from Entrada’s growing pipeline of EEV-therapeutics and our second therapeutic candidate for Duchenne patients. The selection of ENTR-601-45 is based on robust in vitro exon skipping and dystrophin restoration observed in patient derived skeletal and cardiac muscle cells as well as in vivo preclinical data that demonstrated exon skipping levels of over 90% in skeletal muscle in a hDMD mouse model. Entrada presented data in support of ENTR-601-45 at the Muscular Dystrophy Association (MDA) Clinical & Scientific Conference in March 2024.

ENTR-601-45 Showed Robust Exon Skipping and Dystrophin Production in vitro in Patient-derived Skeletal and Cardiac Muscle Cells

Within Entrada’s growing neuromuscular franchise, each EEV-PMO therapeutic candidate has an oligonucleotide sequence designed and optimized for the specific subpopulation of interest. In the figure below we demonstrated that when conjugated to the same EEV, a single dose of our proprietary exon 45 skipping sequence resulted significantly higher levels of exon skipping than a control sequence based on the currently approved therapy casimersen. The Company plans to submit an IND application for ENTR-601-45 in the fourth quarter of 2024.

A Single IV Dose of ENTR-601-45 Showed High Levels of Exon Skipping in hDMD Mouse Skeletal and Heart Muscle After One Week When Compared With an EEV Conjugated Control Exon Skipping Sequence

Clinical Development Plan

We plan to submit regulatory applications in the fourth quarter of 2024 for the global Phase 2 clinical development of ENTR-601-45 in Duchenne patients who are exon 45 skipping amenable. We plan to then initiate a Phase 2b study to assess safety and tolerability as well as evaluate PK. We expect the study will measure changes in dystrophin levels as the primary efficacy endpoint, and a variety of clinical measures as secondary endpoints.

ENTR-601-50

On November 7, 2023, we announced the selection of a third clinical candidate within our Duchenne franchise, ENTR-601-50 for the potential treatment of people living with DMD who are exon 50 skipping amenable. The selection of ENTR-501-50 is based onin vivo preclinical data which demonstrated robust exon 50 skipping across cardiac and skeletal muscle groups. We plan to submit regulatory applications to initiate a global Phase 2 trial in Duchenne patients who are exon 50 skipping amendable in 2025.

Future DMD Franchise Programs

Beyond exploring exon 44, exon 45 and exon 50 skipping amenable candidates, we have also launched research efforts to develop EEV-PMO for exon 51 skipping amenable populations. The exon 51 skipping amenable population represents the largest single Duchenne sub-population, representing approximately 14% of patients. Our goal is to identify a therapeutic candidate for exon 51 skipping amenable patients in 2024.

DM1

DM1 is a rare disease, commonly estimated to affect approximately 110,000 people in the United States and Europe. The disease is caused by a mutation driven alteration of normal RNA structure manifesting as an increase in the number of CTG triplet repeats found in the 3’ non-coding region of the DM1 protein kinase (DMPK) gene. The number of repeats ranges from up to approximately 35 copies in healthy individuals to many thousands in patients with DM1. The resulting transcripts, which contain an expanded CUG tract, aggregate in discrete foci in the nuclei of DM patient cells. The excessive number of CUG repeats form large hairpin loops that entrap the DMPK pre-mRNA in the nucleus and impart toxic activity, referred to as a toxic gain-of-function. Specifically, mutant DMPK pre-mRNA sequesters a critical CUG-binding protein, muscle blind-like protein 1 (MBNL1), forming nuclear foci and inhibiting its ability to perform its normal function of guiding pre-mRNA processing of gene transcription for many other genes. These genes, among others, include insulin receptor signaling (INSR), Ras receptor signaling which is implicated in cell growth (SOS1), Bridging Integrator-1 (BIN1) which is implicated in cardiac development, and LIM domain binding 3 (LDB3) which plays a role in stabilizing the sarcomere (the basic units of muscles) during contraction. As a result, multiple pre-mRNAs that encode key proteins are misprocessed and this contributes to the multisystemic nature of the disease. These abnormal proteins ultimately cause DM1. The progression of DM1 may depend on the growth of the expanded repeat over time, suggesting that stabilization of the repeat is a means to postpone the onset or slow the progression.

DM1 is typically categorized based on age of onset and severity of symptoms into various phenotypes: 75% classical (adult-onset in the second to fourth decade of life); 10% childhood; and 15% congenital. All forms of DM1, except the late-onset form, are associated with high levels of disease burden and in the most severe cases can be associated with premature mortality. Life expectancy ranges from 45 years to 60 years. Seventy percent of early mortality is caused by cardiorespiratory complications. Respiratory failure due to muscle weakness (especially diaphragmatic weakness) causes at least 40% of early mortality, and cardiac abnormalities account for approximately 30%. The clinical course of DM1 is usually slowly progressive, but may become extremely disabling, especially when more generalized limb weakness and respiratory muscle impairment develops. Systemic manifestations such as fatigue, gastrointestinal (GI) complications, cataracts, incontinence and excessive daytime sleepiness greatly impact a patient’s quality of life. As a result, DM1 leads to physical impairment, activity limitations and decreased participation in social activities and work.

There are currently no approved therapies to treat DM1 and treatment is focused largely on symptom management, which is tailored to the system affected and can therefore range from diet modification and physical therapy to surgery and ventilatory support. A previous attempt at treating patients with DM1 with an unconjugated antisense oligonucleotide was discontinued due to lack of efficacy. Therefore, there remains a high unmet medical need for new disease modifying therapies.

VX-670

VX-670 is designed to address the underlying cause of the disease by targeting and blocking the extra CUG triplet repeats occurring in the DMPK mRNA. CAG-repeat antisense oligonucleotides bind CUG repeat RNA and have been shown to block RNA-protein interactions as well as reduce the level of CUG transcription. VX-670 is comprised of a PMO conjugated to an EEV (the same EEV being used in Entrada's DMD programs), which we would expect to sterically block CUG repeats and relieve or prevent the sequestration MBNL1 while leaving DMPK mRNA unaffected and leaving healthy levels of DMPK intact. We are collaborating with Vertex to support the development of VX-670. The Vertex Agreement also includes a four-year global research collaboration whereby Entrada will continue to advance and receive payments for certain research activities related to VX-670, as well as additional DM1-related research activities. Vertex will be responsible for global development, manufacturing and commercialization of VX-670 and any additional programs stemming from Entrada’s DM1 research efforts.

On January 7, 2024 Vertex announced authorization from the MHRA of a clinical trial application for VX-670 for patients with DM1 and initiation of a Phase 1/2 clinical trial in patients with DM1 in Canada and that it will initiate the study in the UK in the near-term. Vertex also noted that they submitted an IND application to the FDA for VX-670. The FDA requested additional information, which resulted in a clinical hold. Vertex is working to address the FDA's comments in order to initiate the study in the U.S.

Additional Preclinical Programs

Pompe disease is a rare, autosomal recessive lysosomal storage disease caused by a mutation in the gene that encodes for glucosidase alpha acid (GAA), which results in an absence or deficiency of GAA protein. Normally, the body uses GAA to break down the complex carbohydrate glycogen and convert it into glucose. Failure to achieve proper breakdown and abnormalities in glycogen metabolism result in the excessive accumulation of glycogen in the body’s cells, particularly in cardiac, smooth, and skeletal muscle cells, which can lead to impairment and degradation of normal tissue and organ function. Patients with Pompe disease experience serious muscle-related problems, including progressive muscle weakness throughout the body, especially in the legs, trunk and diaphragm. As the disorder progresses, breathing problems can lead to respiratory failure.

To date, more than 300 pathogenic mutations have been identified in GAA. Pompe disease is commonly estimated to affect between 5,000 and 10,000 patients in the aggregate in the United States and Europe; however, the advent of newborn screening suggests the disease is underdiagnosed.

Based on the age of onset and severity of symptoms, Pompe disease is typically classified as either infantile-onset Pompe disease (IOPD) or late-onset Pompe disease (LOPD). IOPD is characterized by severe muscle weakness and abnormally diminished muscle tone and usually manifests within the first few months of life. If left untreated, IOPD is often fatal due to progressive cardiac failure, respiratory distress or malnutrition resulting from feeding difficulties. LOPD presents in childhood, adolescence or adulthood. Patients with LOPD typically have milder symptoms, such as reduced mobility and respiratory problems. Patients with LOPD experience progressive difficulty walking and respiratory decline. Initial symptoms of LOPD may be subtle and go unrecognized for years.

The only currently approved therapies for Pompe disease are alglucosidase alfa (Lumizyme in the United States, Myozyme in other geographies), avalglucosidase alfa-ngpt (Nexviazyme in the United States) and cipaglucosidase alfa-atga + miglustat (stabilizer) for patients who are not improving on their current enzyme replacement therapy. All rely upon GAA delivered via IV infusions to break down glycogen. Although infantile patients treated with ERT for Pompe disease have demonstrated improved survival, ERT is not curative, and many patients in long-term observational studies continue to have increased risk of both cardiomyopathy and heart failure. These patients also experience residual muscle weakness, including difficulties swallowing and the attendant increased risk of aspiration. ERT is particularly limited in its ability to improve skeletal muscle myopathy and respiratory dysfunction, primarily due to its inability to penetrate key tissues affected by the disease, a lack of activity in the cytosol and potential immunogenicity. Despite the availability of ERT, there remains significant unmet medical need in patients with either IOPD or LOPD.

Our Solution

Our Pompe disease program focuses on the development of a potentially disease-modifying treatment, which mitigates the production of glycogen in the cytosol of the cell. Leveraging the modularity of our EEV Platform, we are utilizing oligonucleotides that target the mRNA that encodes glycogen synthetase 1 (GYS1), a protein required for the synthesis of glycogen in muscle cells. Our EEV-PMO is expected to provide a complementary mechanism of action to GAA replacement, which increases glycogen processing in the lysosome. We are also developing conjugated constructs that combine both GYS1 knockdown and ERT. Together these therapies may improve therapeutic outcomes.

We believe that an EEV-therapeutics based approach is well suited for the treatment of patients with either IOPD or LOPD.

Summary of Preclinical Data

Our therapeutic strategy involves EEV-PMO induced exon skipping, which is similar to our DMD strategy. We believe the more advanced DMD programs lay the foundation for the potential clinical success of our Pompe disease program. The approach in Pompe disease involves knockdown of GYS1 expression by inducing exon skipping to shift the reading frame and induce the reading of a premature stop codon, as illustrated below, resulting in subsequent nonsense-mediated mRNA decay (NMD). NMD prevents the translation of protein production.

GYS1 Knockdown Via Exon Skipping, To Drive Premature Stop Codon Presentation And mRNA Decay

GYS1/GAA double knockout mice, when compared to the GAA single knockout mice, have exhibited a profound reduction in the amount of glycogen in the heart and skeletal muscles, a significant decrease in lysosomal swelling and autophagic build-up. These cellular-level changes lead to cardiomegaly correction, normalization of glucose metabolism and correction of muscle atrophy. We believe, and medical literature suggests, that, despite the absence of GAA, the elimination of GYS1 plays an important role in glycogen metabolism. Furthermore, this mouse model allows us to test the more general utility of NMD and the more specific goal of GYS1 knockdown by an EEV-PMOin vivo.

Dose-Dependent EEV-PMO Knockdown of GYS1 Gene Expression and Protein Production in Skeletal and Cardiac Muscles Versus PMO Alone

In the experiment above, GAA knockout mice (GAA-/-) were injected with a single IV dose of either 13.5 mg/kg of EEV-PMO, 27 mg/kg of EEV-PMO, 27 mg/kg of PMO or a negative control (vehicle). GYS1 mRNA and protein levels were measured one-week post-injection and a significant knockdown of both was observed in both the EEV-PMO arms, but not in the unconjugated PMO arm. This pharmacodynamic result is notable given that this is a single dose experiment administered at very low doses, and it suggests that GYS1 is an addressable target. We further demonstrated that these protein level reductions were durable up to eight weeks post IV dose of 13.5 mg/kg EEV-PMO.

We believe this result demonstrates the potential of using exon skipping to drive NMD, which potentially opens a broad range of therapeutic indications where a downregulation of gene expression is needed.

Development considerations for GYS1 (Pompe disease and beyond)

We plan to continue studying both GYS1 knockdown and the combination of GYS1 knockdown and enzyme replacement in Pompe disease. Although ERT is an effective treatment for some patients, many will fail to adequately respond, or appear to lose response over time. The expectation is that an ability to retard excess glycogen storage regardless of the source may result in a more effective and durable therapeutic alternative for a wider range of patients.

Beyond Pompe disease, we continue to explore a number of additional diseases where GYS1 knockdown is relevant. In addition, we continue to assess other neuromuscular diseases.

Beyond Neuromuscular Disease

Ocular Disease

High unmet need continues to exist across a wide range of ocular diseases including macular dystrophies, photoreceptor diseases, optic neuropathies among others. Many of these are of genetic origin and potentially addressable via RNA based therapeutics including exon skipping approaches. Despite the benefits of both local delivery and immune privilege many of these diseases have proven to be difficult to treat, as evidenced by a number of clinical failures. The retina is a complex structure consisting of multiple layers of tissue and a range of different cell types. A consistent challenge for developers has been the distribution and uptake of therapeutic candidates broadly, throughout the various layers and cell types across the retina. We believe our EEV-therapeutics can more effectively engage disease specific targets within these tissue layers opening the door to the development of new therapeutic candidates. As such we have preclinical efforts ongoing with the goal of further elucidating the benefits of EEV conjugation. Our lead ocular program targets an indication which results in blindness and affects several thousand exon skipping amenable patients in the United States alone. There are no approved therapies that address the underlying cause of disease. Lead optimization work on both novel oligonucleotide sequences and fit for purpose EEVs is on-going.

Additional Preclinical Development and Discovery Programs

We are leveraging the modularity of our EEV Platform to develop opportunities as diverse as EEV-LNP enabled CRISPR-Cas delivery for gene editing, EEV-LNP based delivery of mRNA, EEV-antibody and peptide drug conjugates, EEV-therapeutic opportunities for central nervous system (CNS) and peripheral nervous system (PNS) disorders, EEV-antibody oligonucleotide conjugates for enhanced tissue tropism in immunology and oncology, as well as for blood brain barrier carriage, EEV-therapeutics with enhanced distribution in retinal tissue for ocular indications, and novel ERT therapies. We regularly explore strategic opportunities to develop potential therapies for patients with devastating diseases.

Genetic Medicine Example

Lipid nanoparticle (LNP) technology has emerged as a promising delivery method for nucleic acids therapeutics, including mRNA vaccines, small interfering RNA and gene editing modalities. Despite tremendous success, LNP delivery platforms still face major challenges, such as limited tissue tropism and poor delivery efficiency due to low endosomal escape. Endosomal escape is especially important for the chronic use of mRNA therapeutics for applications beyond vaccination. We found that EEV-modified LNP (EEV-LNP) significantly enhanced the efficiency of mRNA delivery and gene editing compared to unconjugated LNPin vitro. Through mechanistic studies, we further established the mechanism of uptake for EEV-LNP and observed its ability to target a broad range of cell types and tissues. Overall, these results support the potential of our EEV-LNP platform for improved functional delivery of genomic medicines, with applications in the areas of mRNA delivery and gene editing.

Enzyme Replacement Example

ENTR-501, an intracellular thymidine phosphorylase (TP) enzyme replacement therapyl (ERT), program is in development for the treatment of mitochondrial neurogastrointestinal encephalomyopathy (MNGIE). MNGIE is a slowly progressive, rare disease characterized by elevated levels of thymidine. Preliminary preclinical studies have demonstrated that ENTR-501 reduces toxic thymidine levels below those observed in wild-type mice. We have completed IND-enabling studies for the MNGIE program, including pharmacodynamic and pharmacokinetic studies in mice, and pharmacokinetic and chronic toxicology in NHPs. In July 2023, the Company and Pierrepont Therapeutics, Inc. (Pierrepont) entered into a license agreement (the Pierrepont Agreement) to advance the development and commercialization of ENTR-501. Pierrepont will control development and commercialization of the drug candidate while Entrada retains the right to specified milestones and royalty payments.

We continue to explore additional enzyme replacement opportunities to address a wide range of high unmet need metabolic diseases.

Competition

The biotechnology and biopharmaceutical industries generally, and the neuromuscular disease field specifically, are characterized by rapidly advancing technologies, intense competition and a strong emphasis on proprietary products. While we believe that our technology, the expertise of our team, and our development experience and scientific knowledge in the field of muscle diseases, oligonucleotide therapeutics and manufacturing provide us with competitive advantages, we face potential competition from many different sources, including major pharmaceutical, specialty pharmaceutical and biotechnology companies, academic institutions, governmental agencies and public and private research institutions. Any therapeutic candidates that we successfully develop and commercialize may compete with existing therapies and new therapies that may become available in the future.

Currently, patients with DMD are treated with corticosteroids to manage the inflammatory component of the disease. EMFLAZA (deflazacort) is an FDA-approved corticosteroid marketed by PTC Therapeutics, Inc. (PTC). In addition, there are four FDA-approved exon skipping drugs: EXONDYS 51 (eteplirsen), VYONDYS 53 (golodirsen), and AMONDYS 45 (casimersen), which are PMOs approved for the treatment of patients with DMD who are amenable to exon 51, exon 53 and exon 45 skipping, respectively, and are marketed by Sarepta Therapeutics, Inc. (Sarepta), and VILTEPSO (vitolarsen), a PMO approved for the treatment of patients with DMD who are amenable to exon 53 skipping, which is marketed by Nippon Shinyaku Co. Ltd. Companies focused on developing treatments for DMD that target dystrophin mechanisms, as does our DMD program, include Sarepta with SRP -5051, a peptide-linked PMO currently being evaluated following a Phase 2 clinical trial for patients amenable to exon 51 skipping along with additional exons in preclinical development, Nippon Shinyaku Co. Ltd., which recently completed a Phase 1/2 clinical trial for patients amenable to exon 44 skipping in Japan, PTC with ataluren, a small molecule targeting nonsense mutations in a Phase 3 clinical trial, Avidity Biosciences, Inc. (Avidity), which announced the preliminary data from its ongoing Phase 1/2 clinical trial with antibody oligonucleotide conjugates for exon 44 (AOC-1044), and has similar programs for patients amenable to exon 45, and exon 51 skipping in preclinical development, Wave Life Sciences Ltd., which is clinically evaluating WVE-N531, a splicing clinical candidate that is designed to target exon 53 within the dystrophin gene, Dyne Therapeutics, Inc. (Dyne), which is pursuing antibody fragment-oligonucleotide conjugates for exons 44, 45, 51 (clinical candidate DYNE-251), and 53, PepGen, Inc. with PGN-EDO51, a clinical candidate designed to address exon 51, along with discovery programs targeting exons 53, 44, and 45, and BioMarin Pharmaceutical Inc., which is in preclinical development with BMN 351, an antisense oligonucleotide therapy for exon 51. In addition, several companies are developing gene therapies to treat DMD, including Pfizer Inc. (PF-06939926), Sarepta (SRP-9001; delandistrogene moxeparvovec-rokl approved for ambulatory 4-5 year old patients), Solid Biosciences Inc. (SGT-003), and REGENXBIO (RGX-202). Gene editing treatments that are in preclinical development are also being pursued by Vertex and Sarepta. We are also aware of several companies targeting non-dystrophin mechanisms for the treatment of DMD.

We expect to face competition from existing products and products in development for each of our therapeutic candidates. There are currently no approved therapies to treat the underlying cause of DM1. Therapeutic candidates currently in development to treat DM1 include: tideglusib, a GSK3-ß inhibitor in late-stage clinical development by AMO Pharma Ltd. for the congenital phenotype of DM1; AOC-1001, an antibody linked siRNA in clinical development by Avidity; DYNE-101, an antibody fragment conjugated to an ASO targeting DM1 protein kinase knockdown in clinical development by Dyne; EDODM1, a linear peptide conjugated to a PMO targeting CUG repeats in clinical development by PepGen, Inc.; a small molecule targeting GTG repeats in preclinical development by Design Therapeutics, Inc.; an RNA-targeting gene therapy in preclinical development by Locana, Inc.; and small molecules interacting with RNA in preclinical development by Expansion Therapeutics, Inc.

The only currently-approved therapies for Pompe disease are alglucosidase alfa (Lumizyme in the United States, Myozyme in other geographies), avalglucosidase alfa-ngpt (Nexviazyme in the United States) and cipaglucosidase alfa-atga + miglustat, which rely on the delivery of GAA via IV infusions. There is one GYS1 inhibitor in clinical development from Maze Therapeutics Inc. and another from Aro Biotherapeutics. There are four gene therapies in the early stages of clinical development from Astellas Pharma Inc., Bayer AG, Roche Holding AG and Lacerta Therapeutics, Inc. There are gene therapies in preclinical development from AVROBIO, Inc. and Amicus Therapeutics.

Many of our competitors, either independently or with strategic partners, have substantially greater financial, technical and human resources than we do. Accordingly, our competitors may be more successful than we are in research and development, manufacturing, preclinical testing, conducting clinical trials, obtaining regulatory approval for treatments and achieving widespread market acceptance. These companies also compete with us in recruiting and retaining qualified scientific and management personnel, establishing clinical trial sites and patient registration for clinical trials and acquiring technologies complementary to, or necessary for, our programs. Smaller or early-stage companies may also prove to be significant competitors, particularly through collaborative arrangements with large and established companies.

Our commercial potential could be substantially limited if our competitors develop and commercialize products that are more effective, safer, less toxic, more convenient or less expensive than any products we may develop. In geographies that are critical to our commercial success, competitors may also obtain regulatory approvals before us, resulting in our competitors building a strong market position in advance of the entry of our products. In addition, our ability to compete may be affected in many cases by insurers or other third-party payers seeking to encourage the use of other drugs. The key competitive factors affecting the success of any products we may develop are likely to be their efficacy, safety, convenience, price and availability of reimbursement.

Intellectual Property

We strive to protect our proprietary technology, inventions, improvements, platforms, program candidates, therapeutic candidates and components thereof, their methods of use and processes for their manufacture that we believe are important to our business, including by obtaining, maintaining, defending and enforcing patent and other intellectual property rights for the foregoing in the United States and in foreign jurisdictions. We also rely on trade secrets and confidentiality agreements to protect our confidential information and know-how and other aspects of our business that are not amenable to, or that we do not consider appropriate for, patent protection.

Our future commercial success depends in part on our ability to:

•obtain, maintain, enforce and defend patent and other intellectual property rights for our important technology, inventions and know-how; preserve the confidentiality of our trade secrets and other confidential information;

•obtain and maintain licenses to use and exploit intellectual property owned or controlled by third parties;

•operate without infringing, misappropriating or otherwise violating any valid and enforceable patents and other intellectual property rights of third parties; and

•defend against challenges and assertions by third parties challenging the validity or enforceability of our intellectual property rights, or our rights in our intellectual property, or asserting that the operation of our business infringes, misappropriates or otherwise violates their intellectual property rights.

Our portfolio consists of owned and exclusively licensed patents and applications. As of March 6, 2024, there are 65 distinct patent families (39 families with non-provisional applications and 26 families with pending provisional applications) covering compositions of matter, manufacturing and uses related to our business. Among these patent families, we have 238 pending applications (including PCT, provisional and non-provisional applications) in the U.S. and Europe,as well as other countries of strategic value; and 73 granted patents in the U.S., Europe, China, India, Japan, and Hong Kong (including a total of 45 member state validations of three European patents). Of these pending applications and granted patents, the licensed patent applications are pending in U.S., Europe, China, Canada, Hong Kong, Japan, and Taiwan; and licensed patents are granted in the U.S., Europe, China, Japan, Taiwan, and Hong Kong.

Our owned and licensed patent estate covers various aspects of our programs and technology, including various embodiments of our EEV Platform; proprietary enzyme, peptide, oligonucleotide and CRISPR conjugates; methods of treatment; and aspects of manufacturing. The portfolio includes patents covering certain embodiments of the EEV Platform that don’t relate to our lead therapeutic candidates with granted patents in the U.S. (3), India, Japan, China, Hong Kong and Europe (including 37 European validation states). The extent to which any patents, if and when granted, will cover our therapeutic candidates is uncertain. Any U.S. or foreign patents issued from national stage filings of our PCT patent applications and any U.S. patents issued from non-provisional applications we have filed or may file in connection with our provisional patent applications would be scheduled to expire on various dates from 2036 through 2044, without taking into account any possible patent term adjustments or extensions and assuming payment of all appropriate maintenance, renewal, annuity and other governmental fees.

Patent Prosecution

A PCT patent application is not eligible to become an issued patent until, among other things, we file one or more national stage patent applications in the jurisdictions in which we seek patent protection and do so within prescribed timelines of the PCT patent application’s priority date. These prescribed timelines are generally 30 months, 31 months or 32 months, depending on the jurisdiction. If we do not timely file any national stage patent applications, we may lose our priority date and any potential patent protection on the inventions disclosed in such PCT patent application.

Moreover, a provisional patent application is not eligible to become an issued patent. A provisional patent application may serve as a priority filing for a non-provisional patent application we file within 12 months of such provisional patent application. If we do not timely file non-provisional patent applications, we may lose our priority date with respect to our existing provisional patent applications and any potential patent protection on the inventions disclosed in our provisional patent applications.

While we intend to timely file additional provisional patent applications, as well as national stage and non-provisional patent applications relating to our provisional applications or PCT patent applications, we cannot predict whether any of our patent applications will result in the issuance of patents. If we do not successfully obtain patent protection, or if the scope of the patent protection we or our licensors obtain with respect to our therapeutic candidates or technology is insufficient, we will be unable to use patent protection to prevent others from using our technology or from developing or commercializing technology and products similar or identical to ours or other similar competing products and technologies. Our ability to stop third parties from making, using, selling, offering to sell, importing or otherwise commercializing any of our technology, inventions and improvements, either directly or indirectly, will depend in part on our success in obtaining, maintaining, defending and enforcing patent claims that cover our technology, inventions and improvements.

The patent positions of companies like ours are generally uncertain and involve complex legal and factual questions. The protection afforded by a patent varies on a product-by-product basis, from jurisdiction-to-jurisdiction, and depends upon many factors, including the type of patent, the scope of its coverage, the availability of patent term adjustments and regulatory-related patent term extensions, the availability of legal remedies in a particular jurisdiction, and the validity and enforceability of the patent. Patent laws and related enforcement in various jurisdictions outside of the United States are uncertain and may not protect our rights to the same extent as the laws of the United States. Changes in the patent laws and rules, whether by legislation, judicial decisions or regulatory interpretation, in the United States and other jurisdictions may have uncertain affects that could improve or diminish our ability to protect our inventions and obtain, maintain, defend and enforce our patent rights, and could therefore affect the value of our business in uncertain ways.

The area of patent and other intellectual property rights in biotechnology is evolving and has many risks and uncertainties, and third parties may have blocking patents and other intellectual property that could be used to prevent us from commercializing our platform and therapeutic candidates and practicing our proprietary technology. Our patent rights may be challenged, narrowed, circumvented, invalidated or ruled unenforceable, which could limit our ability to stop third parties from marketing and commercializing related platforms or therapeutic candidates or limit the term of patents that cover our platform and any therapeutic candidates. In addition, the rights granted under any issued patents may not provide us with protection or competitive advantages against third parties with similar technology, and third parties may independently develop similar technologies.

Moreover, because of the extensive time required for development, testing and regulatory review of a potential product, it is possible that before any of our therapeutic candidates can be commercialized, any related patent may expire or remain in force for only a short period following commercialization, thereby reducing any competitive advantage provided by the patent. For this and other risks related to our proprietary technology, inventions, improvements, platforms and therapeutic candidates and intellectual property rights related to the foregoing, please see the section entitled “Risk Factors—Risks Related to Our Intellectual Property.”

Patent Term

The term of individual patents depends upon the laws of the jurisdictions in which they are obtained. In most jurisdictions in which we file, the patent term is 20 years from the filing date of a PCT patent application or, if a PCT application is not filed, the earliest date of filing of the first non-provisional patent application to which the patent claims priority. However, the term of U.S. patents may be extended or adjusted for delays incurred due to compliance with FDA requirements or by delays encountered during prosecution that are caused by the United States Patent and Trademark Office (USPTO). For example, in the United States, a patent claiming a new chemical entity or biologic product, its method of use or its method of manufacture may be eligible for a limited patent term extension under the Drug Price Competition and Patent Term Restoration Act of 1984 (the Hatch-Waxman Act) for up to five years beyond the normal expiration date of the patent. Patent term extension cannot be used to extend the remaining term of a patent past a total of 14 years from the product’s approval date in the United States. Only one patent applicable to an approved product is eligible for the extension, and the application for the extension must be submitted prior to the expiration of the patent for which extension is sought and within 60 days of FDA approval of the product. A patent that covers multiple products for which approval is sought can only be extended in connection with one of the approvals. During the period of extension, if granted, the scope of exclusivity is limited to the approved product for approved uses. Some foreign jurisdictions, including Europe and Japan, have analogous patent term extension provisions, which allow for extension of the term of a patent that covers a drug approved by the applicable foreign regulatory agency. For more information on patent term extensions, see “Business—Government Regulation—Patent Term Restoration and Extension and Marketing Exclusivity.” In the future, if and when any therapeutic candidates we may develop receive FDA approval, we expect to apply for patent term extensions on issued patents covering those therapeutic candidates. Moreover, we intend to seek patent term adjustments and extensions for any of our issued patents in any jurisdiction where such adjustments and extensions are available. However, there is no guarantee that the applicable authorities, including the USPTO and the FDA, will agree with our assessment of whether such adjustments and extensions should be granted, and even if granted, the length of such adjustments and extensions.

Trade Secrets

In addition to patent protection, we also rely on trade secrets, know-how, unpatented technology and other proprietary information to strengthen our competitive position. We currently, and may continue in the future continue to, rely on third parties to assist us in developing and manufacturing our products. Accordingly, we must, at times, share trade secrets, know-how, unpatented technology and other proprietary information, including those related to our platform, with them. We may in the future also enter into research and development collaborations with third parties that may require us to share trade secrets, know-how, unpatented technology and other proprietary information under the terms of research and development partnerships or similar agreements. Nonetheless, we take steps to protect and preserve our trade secrets and other confidential and proprietary information and prevent the unauthorized disclosure of the foregoing, including by entering into non-disclosure and invention assignment agreements with parties who have access to our trade secrets or other confidential and proprietary information, such as employees, consultants, outside scientific collaborators, contract research and manufacturing organizations, sponsored researchers and other advisors, at the commencement of their employment, consulting or other relationships with us. In addition, we take other appropriate precautions, such as maintaining physical security of our premises and physical and electronic security of our information technology systems, to guard against any misappropriation or unauthorized disclosure of our trade secrets and other confidential and proprietary information by third parties.

Despite these efforts, third parties may independently develop substantially equivalent proprietary information and techniques or otherwise gain access to our trade secrets or other confidential or proprietary information. In addition, we cannot provide any assurances that all of the foregoing non-disclosure and invention assignment agreements have been duly executed, and any of the counterparties to such agreements may breach them and disclose our trade secrets and other confidential and proprietary information. Although we have confidence in the measures we take to protect and preserve our trade secrets and other confidential and proprietary information, they may be inadequate, our agreements or security measures may be breached, and we may not have adequate remedies for such breaches. Moreover, to the extent that our employees, contractors, consultants, collaborators and advisors use intellectual property owned by others in their work for us, disputes may arise as to our rights in any know-how or inventions arising out of such work. For more information, please see the section entitled “Risk Factors—Risks Related to Our Intellectual Property.”

License Agreement with The Ohio State University

On May 12, 2017, we entered into an option agreement with Ohio State Innovation Foundation (OSIF), an affiliate of The Ohio State University (OSU) responsible for the commercialization of technology developed at or created by or for OSU, in which the Company obtained an option (OSIF Option Agreement) to license all patents and patent applications involving technologies using cell-penetrating peptides arising out of or related to specified invention disclosures or through a sponsored research agreement executed with OSU on the same date (OSU SRA). On September 26, 2018, we exercised our option pursuant to the terms of the OSIF Option Agreement, and on December 14, 2018, we entered into a license agreement (OSIF License Agreement) for an exclusive, worldwide, sublicensable license under these patents and patent rights, and a non-exclusive, worldwide, sublicensable license under certain related know-how, to develop, commercialize or otherwise exploit products based on these cell-penetrating technologies for the treatment, prevention and diagnosis of any and all diseases or conditions. In addition, the OSIF License Agreement grants a worldwide, perpetual, irrevocable, fully-paid, royalty-free, sublicensable, exclusive license to any rights held by OSIF, OSU or its affiliates covering specifically identified cell-penetrating platform technology.

The term of the OSIF License Agreement will continue until the later of (a) the expiration of the last to expire of the exclusively licensed patent rights, or (b) the end of our obligation to pay royalties under the OSIF License Agreement. Such obligation ends, on a licensed product-by-licensed product and country-by-country basis, on the later of (1) expiration of the last to expire of the valid claims of the exclusively licensed patent rights covering such licensed product in such country, or (2) ten (10) years after the first commercial sale of such licensed product in such country. The last to expire exclusively licensed patent rights and valid claim of such exclusively licensed patent rights are estimated to expire by 2042, excluding any patent term adjustments or extensions. Upon expiration of the OSIF License Agreement at the end of the royalty term, the Company will maintain all license rights as a perpetual and fully paid-up license. Both parties have the right to terminate under certain enumerated circumstances. At our option, we may terminate the OSIF License Agreement for any reason with ninety days’ (90) written notice, or if OSIF is in material breach, after providing thirty (30) days’ notice of termination. OSIF may terminate the agreement at its option immediately upon delivery of written notice if any specified events occur, including failure by the Company to make payments due under the agreement and if the Company is in material breach, in each case pursuant to specified cure periods.

We have typical diligence obligations under the OSIF License Agreement, including the obligation to use commercially reasonable efforts to develop and commercialize at least one licensed product. We may also be obligated to pay aggregate milestone payments of up to $7,950,000, tiered royalties on sales at low single digit percentages, a license maintenance fee of $25,000 per year beginning in 2021 and continuing until the first year in which commercial sales of a licensed product pursuant to the agreement commence. After such commercialization, we are required to make minimum annual payments of $125,000. In addition, in the event of a sublicense, under certain circumstances we may be required to pay up to 15% of non-royalty sublicensing consideration.

Commercialization

Excluding ENTR-501 and VX-670, we intend to retain significant development and commercial rights to our potential therapeutic candidates and, if marketing approval is obtained, to commercialize our therapeutic candidates on our own, or potentially with a partner, in the United States and other regions. We currently have no sales, marketing, or commercial product distribution capabilities. We intend to build the necessary infrastructure and capabilities over time for the United States, and potentially other regions, following further advancement of our therapeutic candidates. We believe that such a focused sales and marketing organization will be able to address the key specialists in treating the patient populations for which our therapeutic candidates are being developed. Clinical data, the size of the addressable patient population, and the size of the commercial infrastructure and manufacturing needs may all influence or alter our commercialization plans. The responsibilities of the marketing organization would include developing educational initiatives with respect to approved products and establishing relationships with researchers and practitioners in relevant fields of medicine.

Manufacturing and Supply

We do not own or operate manufacturing facilities. We currently rely on third-party contract manufacturing organizations (CMOs), and suppliers for EEVs, including linkers, and nucleotides that comprise ENTR-601-44, ENTR 601-45, ENTR-601-50, VX-670, our other potential therapeutic candidates, and the conjugation of these components, and we expect to continue to do so to support our IND-enabling studies and our clinical trials and commercial activities. However, we may seek to establish our own manufacturing facility for IND-enabling studies, clinical studies and long-term commercial supply. As we scale manufacturing, we intend to continue to expand and strengthen our network of CMOs. We believe there are multiple sources for all of the materials required for the manufacture of our therapeutic candidates, as well as multiple CMOs who could assemble the aforementioned components that comprise our potential therapeutic candidates.

Manufacturing is subject to extensive regulations that impose procedural and documentation requirements. These regulations govern record keeping, manufacturing processes and controls, personnel, quality control and quality assurance. Our CMOs are required to comply with these regulations and are assessed through regular monitoring and formal audits. Our third-party manufacturers are required to manufacture any therapeutic candidates we develop under current Good Manufacturing Practice (cGMP), requirements and other applicable laws and regulations.

We have personnel with extensive technical, manufacturing, analytical and quality experience to oversee all contracted manufacturing and testing activities.

Government Regulation

Government authorities in the United States, at the federal, state and local level and in other countries and jurisdictions, including the European Union, extensively regulate, among other things, the research, development, testing, manufacture, pricing, reimbursement, sales, quality control, approval, packaging, storage, recordkeeping, labeling, advertising, promotion, distribution, marketing, post-approval monitoring and reporting and import and export of drugs and biological products such as those we are developing. The processes for obtaining marketing approvals in the United States and in foreign countries and jurisdictions, along with subsequent compliance with applicable statutes and regulations and other regulatory authorities, require the expenditure of substantial time and financial resources.

Licensure and Regulation of Drugs and Biologics in the United States

In the United States, where we are initially focusing our product development, the FDA regulates drugs under the Federal Food, Drug, and Cosmetic Act (FDCA), and biologics under the FDCA and the Public Health Service Act (PHSA), and their implementing regulations. Both drugs and biologics are also subject to other federal, state and local statutes and regulations. Our therapeutic candidates are early-stage and have not been approved by the FDA for marketing in the United States. Based on our novel therapeutic approach and the broad potential applicability of our EEV Platform to deliver a variety of therapeutic modalities into cells, we are developing therapeutic candidates that would be regulated under the

FDCA, and/or the PHSA, and their implementing regulations, as drugs or biologics, depending on the modality of each product candidate. The failure to comply with the applicable U.S. requirements at any time during the product development process, including preclinical testing, clinical testing, the approval process, or post-approval process, may subject an applicant to delays in the conduct of the study, regulatory review and approval and/or administrative or judicial sanctions. These sanctions may include, but are not limited to, the FDA’s refusal to allow an applicant to proceed with clinical testing, refusal to approve pending applications, license suspension, or revocation, withdrawal of an approval, warning letters, adverse publicity, product recalls, product seizures, total or partial suspension of production or distribution, injunctions, fines and civil or criminal investigations and penalties brought by the FDA or the Department of Justice (DOJ), and other governmental entities, including state agencies.

An applicant seeking approval to market and distribute a new drug or biologic in the United States generally must satisfactorily complete each of the following steps: preclinical laboratory tests, animal studies and formulation studies all performed in accordance with the FDA’s Good Laboratory Practices (GLP) regulations, as applicable; completion of the manufacture, under current Good Manufacturing Practices (cGMP) conditions, of the drug substance and drug product that the sponsor intends to use in human clinical trials along with required analytical and stability testing; submission to the FDA of an IND, for human clinical testing, which must become effective before human clinical trials may begin; approval by an independent institutional review board (IRB), representing each clinical trial site before each clinical trial site may be initiated; performance of adequate and well-controlled human clinical trials, in accordance with current Good Clinical Practices (GCP), and any additional nonclinical studies required to establish the safety, efficacy, potency and purity of the product candidate for each proposed indication; preparation and submission to the FDA of a new drug application (NDA), or a Biologics License Application (BLA), for a biologic product, requesting marketing for one or more proposed indications, including submission of detailed information on the manufacture and composition of the product in clinical development and proposed labelling; review of the product by an FDA advisory committee, where appropriate or if applicable; satisfactory completion of one or more FDA inspections of the manufacturing facility or facilities, including those of third parties, at which the product, or components thereof, are produced to assess compliance with cGMP and to assure that the facilities, methods and controls are adequate to preserve the product’s identity, strength, quality and purity; satisfactory completion of any FDA audits of the preclinical studies and clinical trial sites to assure compliance with GLP, as applicable, and GCP, and the integrity of clinical data in support of the NDA or BLA; payment of user fees under the Prescription Drug User Fee Act (PDUFA); securing FDA approval of the NDA or BLA; and compliance with any post-approval requirements, including the potential requirement to implement a Risk Evaluation and Mitigation Strategy (REMS), and any post-approval studies or other post-marketing commitments required by the FDA.

Preclinical Studies and IND Application

Before testing any therapeutic product candidate in humans, the product candidate must undergo preclinical testing. Preclinical tests include laboratory evaluations of product chemistry, formulation and stability, as well as studies to evaluate the potential for efficacy and toxicity in animal studies. The conduct of the preclinical tests and formulation of the compounds for testing must comply with federal regulations and requirements. The results of the preclinical tests, together with manufacturing information and analytical data, are submitted to the FDA as part of an IND application.

An IND is an exemption from the FDCA that allows an unapproved product candidate to be shipped in interstate commerce for use in a clinical trial and a request for FDA authorization to administer such investigational product to humans. The IND automatically becomes effective 30 days after receipt by the FDA, unless before that time the FDA raises concerns or questions about the product or conduct of the proposed clinical trial, including concerns that human research subjects will be exposed to unreasonable health risks. In that case, the IND sponsor and the FDA must resolve any outstanding FDA concerns before the clinical trials can begin or recommence.

As a result, submission of the IND may result in the FDA not allowing the trials to commence or allowing the trial to commence on the terms originally specified by the sponsor in the IND. If the FDA raises concerns or questions either during this initial 30-day period, or at any time during the IND review process, it may choose to impose a partial or complete clinical hold. Clinical holds may be imposed by the FDA when there is concern for patient safety, and may be a result of new data, findings, or developments in clinical, preclinical and/or chemistry, manufacturing and controls or where there is non-compliance with regulatory requirements. This order issued by the FDA would delay either a proposed clinical trial or cause suspension of an ongoing trial, until all outstanding concerns have been adequately addressed and the FDA has notified the company that investigations may proceed. A separate submission to an existing IND must also be made for each successive clinical trial conducted during drug development, and the FDA must grant permission, either explicitly or implicitly by not objecting, before each clinical trial can begin.

Human Clinical Trials in Support of an NDA or BLA

Clinical trials involve the administration of the investigational product candidate to healthy volunteers or patients with the disease or condition to be treated under the supervision of qualified investigators in accordance with GCP requirements. Clinical trials are conducted under protocols detailing, among other things, the objectives of the trial, inclusion and exclusion criteria, the parameters to be used in monitoring safety, and the effectiveness criteria to be evaluated. A protocol for each clinical trial and any subsequent protocol amendments must be submitted to the FDA as part of the IND.

A sponsor who wishes to conduct a clinical trial outside the United States may, but need not, obtain FDA authorization to conduct the clinical trial under an IND. When a foreign clinical trial is conducted under an IND, all FDA IND requirements must be met unless waived. The FDA will accept a well-designed and well-conducted foreign clinical study not conducted under an IND if the study was conducted in accordance with GCP requirements, and the FDA is able to validate the data through an onsite inspection if deemed necessary. The GCP requirements encompass both ethical and data integrity standards for clinical trials. The FDA’s regulations are intended to help ensure the protection of human subjects enrolled in non-IND foreign clinical trials, as well as the quality and integrity of the resulting data. They further help ensure that non-IND foreign trials are conducted in a manner comparable to that required for clinical trials in the United States.

Further, each clinical trial must be reviewed and approved by an IRB either centrally or individually at each institution at which the clinical trial will be conducted. The IRB will consider, among other things, clinical trial design, patient informed consent, ethical factors, the safety of human subjects, and the possible liability of the institution. An IRB must operate in compliance with FDA regulations. The FDA, IRB, or the clinical trial sponsor may suspend or discontinue a clinical trial at any time for various reasons, including a finding that the clinical trial is not being conducted in accordance with GCP requirements or that the participants are being exposed to an unacceptable health risk. Clinical testing also must satisfy extensive GCP rules and the requirements for informed consent.

Additionally, some clinical trials are overseen by an independent group of qualified experts organized by the clinical trial sponsor, known as a data safety monitoring board (DSMB), or data monitoring committee (DMC). This group may recommend continuation of the trial as planned, changes in trial conduct, or cessation of the trial at designated check points based on certain available data from the trial to which only the DSMB/DMC has access. Finally, certain clinical trials involving recombinant or synthetic nucleic acid molecules may be subject to review and approval of an Institutional Biosafety Committee (IBC), in accordance with NIH Guidelines for Research Involving Recombinant or Synthetic Nucleic Acid Molecules (NIH Guidelines). An IBC is a local institutional committee that reviews and oversees research utilizing recombinant or synthetic nucleic acid molecules at that institution. The IBC assesses the safety of the research and identifies any potential risk to public health or the environment, and such review may result in some delay before initiation of a clinical trial. While the NIH Guidelines are not mandatory unless the research in question is being conducted at or sponsored by institutions receiving NIH funding for recombinant or synthetic nucleic acid molecule research, many companies and other institutions not otherwise subject to the NIH Guidelines voluntarily follow them.

Clinical trials typically are conducted in three sequential phases, but the phases may overlap or be combined. Additional studies may be required after approval.

•Phase 1 clinical trials are initially conducted in a limited population to test the product candidate for safety, including adverse effects, dose tolerance, absorption, metabolism, distribution, excretion and pharmacodynamics in healthy subjects or patients.

•Phase 2 clinical trials are generally conducted in a limited patient population to identify possible adverse effects and safety risks, evaluate the efficacy of the product candidate for specific targeted indications and determine dose tolerance and optimal dosage. Multiple Phase 2 clinical trials may be conducted by the sponsor to obtain information prior to beginning larger and more costly Phase 3 clinical trials.

•Phase 3 clinical trials typically proceed if the Phase 2 clinical trials demonstrate that a dose range of the product candidate is potentially effective and has an acceptable safety profile. Phase 3 clinical trials are generally undertaken within an expanded patient population to further evaluate dosage, provide substantial evidence of clinical efficacy and further test for safety in an expanded and diverse patient population at multiple, geographically dispersed clinical trial sites. A well-controlled, statistically robust Phase 3 trial may be designed to deliver the data that regulatory authorities will use to decide whether or not to approve, and, if approved, how to appropriately label a therapeutic.

In some cases, the FDA may approve an NDA or BLA for a product but require the sponsor to conduct additional clinical trials to further assess the product’s safety and effectiveness after approval. Such post-approval trials are typically referred to as Phase 4 clinical trials. These studies are used to gain additional experience from the treatment of patients in the intended therapeutic indication and to document a clinical benefit for products approved under accelerated approval regulations. If the FDA approves a product while a company has ongoing clinical trials that were not necessary for approval, a company may be able to use the data from these clinical trials to meet all or part of any Phase 4 clinical trial requirement or to request a change in the product labeling. The failure to exercise due diligence with regard to conducting Phase 4 clinical trials could result in withdrawal of approval for products.

Information about applicable clinical trials must be submitted within specific timeframes to the NIH for public dissemination on its ClinicalTrials.gov website.

Under the Pediatric Research Equity Act of 2003, an NDA, BLA or supplement thereto must contain data that are adequate to assess the safety and effectiveness of the product for the claimed indications in all relevant pediatric subpopulations, and to support dosing and administration for each pediatric subpopulation for which the product is safe and effective. The FDCA requires that a sponsor who is planning to submit a marketing application for a product that includes a new active ingredient, new indication, new dosage form, new dosing regimen or new route of administration submit an initial Pediatric Study Plan (PSP), within sixty days of an end-of-Phase 2 meeting or as may be agreed between the sponsor and FDA. Those plans must contain an outline of the proposed pediatric study or studies the applicant plans to conduct, including study objectives and design, any deferral or waiver requests, and other information required by regulation. The sponsor and the FDA must reach agreement on the PSP. The FDA or the applicant may request an amendment to the plan at any time.

The FDA may, on its own initiative or at the request of the applicant, grant deferrals for submission of some or all pediatric data until after approval of the product for use in adults, or full or partial waivers from the pediatric data requirements. Additional requirements and procedures relating to deferral requests and requests for extension of deferrals are contained in the Food and Drug Administration Safety and Innovation Act. Unless otherwise required by regulation, the pediatric data requirements do not apply to products with orphan designation.

Expanded Access to an Investigational Drug for Treatment Use

Expanded access, sometimes called “compassionate use,” is the use of investigational products outside of clinical trials to treat patients with serious or immediately life-threatening diseases or conditions when there are no comparable or satisfactory alternative treatment options. The rules and regulations related to expanded access are intended to improve access to investigational products for patients who may benefit from investigational therapies. FDA regulations allow access to investigational products under an IND by the company or the treating physician for treatment purposes on a case-by-case basis for: individual patients (single-patient IND applications for treatment in emergency settings and non-emergency settings); intermediate-size patient populations; and larger populations for use of the investigational product under a treatment protocol or treatment IND application.

Expanded access may be appropriate when all of the following criteria apply: patient(s) have a serious or immediately life-threatening disease or condition, and there is no comparable or satisfactory alternative therapy to diagnose, monitor, or treat the disease or condition; patient enrollment in a clinical trial is not possible; the potential patient benefit justifies the potential risks of the treatment and the potential risks are not unreasonable in the context or condition to be treated; and the expanded use of the investigational drug for the requested treatment will not interfere with initiation, conduct, or completion of clinical investigations that could support marketing approval of the product or otherwise compromise the potential development of the product. There is no obligation for a sponsor to make its drug products available for expanded access; however, as required by the 21 st Century Cures Act (Cures Act), a sponsor must make its policy regarding evaluating and responding to expanded access requests publicly available.

In addition, on May 30, 2018, the Right to Try Act was signed into law. The law, among other things, provides a federal framework for certain patients to access certain investigational products that have completed a Phase 1 clinical trial and that are undergoing investigation for FDA approval. Under certain circumstances, eligible patients can seek treatment without enrolling in clinical trials and without obtaining FDA permission under the FDA expanded access program. There is no obligation for a manufacturer to make its investigational products available to eligible patients as a result of the Right to Try Act.

Compliance with cGMP Requirements

Before approving an NDA or BLA, the FDA will typically inspect the facility or facilities where the product is manufactured. The FDA will not approve an application unless it determines that the manufacturing processes and facilities are in compliance with cGMP requirements and adequate to assure consistent production of the product within required specifications. The PHSA emphasizes the importance of manufacturing controls for products like biologics whose attributes cannot be precisely defined.

Manufacturers and others involved in the manufacture and distribution of approved drugs and biologics, and those supplying products, ingredients, and components of them, must also register their establishments with the FDA and certain state agencies. Both domestic and foreign manufacturing establishments must register and provide additional information to the FDA upon their initial participation in the manufacturing process. Any product manufactured by or imported from a facility that has not registered, whether foreign or domestic, is deemed misbranded under the FDCA. Establishments may be subject to periodic unannounced inspections by government authorities to ensure compliance with cGMPs and other laws. Noncompliance with such requirements can lead to adverse findings by the FDA during these inspections; in instances of significant or continued noncompliance, such adverse findings can serve as the basis for additional regulatory action by the FDA, including but not limited to warning and “untitled” letters.

Review and Approval of an NDA or BLA

The results of product candidate development, preclinical testing and clinical trials, including negative or ambiguous results as well as positive findings, are submitted to the FDA as part of an NDA or BLA requesting approval to market the product. The NDA or BLA must contain extensive manufacturing information and detailed information on the composition of the product and proposed labeling as well as payment of a user fee. Under federal law, the submission of most NDAs and BLAs are subject to an application user fee. The sponsor of an approved NDA or BLA is also subject to an annual program fee. Certain exceptions and waivers are available for some of these fees, such as an exception from the application fee for products with orphan designation and a waiver for certain small businesses.

The FDA has 60 days after submission of the application to conduct an initial review to determine whether to accept it for filing based on the agency’s threshold determination that it is sufficiently complete to permit substantive review. Once the submission has been accepted for filing, the FDA begins an in-depth review of the application. Under the goals and policies agreed to by the FDA under PDUFA, the FDA has ten months in which to complete its initial review of a standard application and respond to the applicant, and six months for a priority review of the application. The FDA does not always meet its PDUFA goal dates for standard and priority NDAs and BLAs. The review process may be significantly extended by FDA requests for additional information or clarification. The review process and the PDUFA goal date may be extended by three months if the FDA requests or if the applicant otherwise provides additional information or clarification regarding information already provided in the submission within the last three months before the PDUFA goal date.

The FDA reviews an NDA or BLA to determine, among other things, whether the product is safe and effective and whether the facility in which it is manufactured, processed, packaged or held meets standards designed to assure the product’s continued safety, quality and purity. On the basis of the FDA’s evaluation of the application and accompanying information, including the results of the inspection of the manufacturing facilities and any FDA audits of preclinical and clinical trial sites to assure compliance with GCPs, the FDA may issue an approval letter or a complete response letter. An approval letter authorizes commercial marketing of the product with specific prescribing information for specific indications. If the application is not approved, the FDA will issue a complete response letter, which will contain the conditions that must be met in order to secure final approval of the application, and when possible, will outline recommended actions the sponsor might take to obtain approval of the application. Sponsors that receive a complete response letter have one year to submit to the FDA information that represents a complete response to the issues identified by the FDA. The FDA will then re-review the application, taking into consideration the response. Failure to respond to a complete response letter will serve as a withdrawal of an application. The FDA will not approve an application until issues identified in any complete response letters have been addressed.

The FDA may also refer the application to an advisory committee for review, evaluation and recommendation as to whether the application should be approved. In particular, the FDA may refer applications for novel products or products that present difficult questions of safety or efficacy to an advisory committee.

Typically, an advisory committee is a panel of independent experts, including clinicians and other scientific experts, that reviews, evaluates and provides a recommendation as to whether the application should be approved and under what conditions. The FDA is not bound by the recommendations of an advisory committee, but it considers such recommendations carefully when making decisions.

If the FDA approves a new product, it may limit the approved indication(s) for use of the product. It may also require that contraindications, warnings, or precautions be included in the product labeling. In addition, the FDA may call for post-approval studies, including Phase 4 clinical trials, to further assess the product’s efficacy and/or safety after approval. The agency may also require testing and surveillance programs to monitor the product after commercialization, or impose other conditions, including distribution restrictions or other risk management mechanisms, including a REMS program, to help ensure that the benefits of the product outweigh the potential risks. A REMS can include medication guides, communication plans for healthcare professionals and elements to assure safe use (ETASU). ETASU can include, but are not limited to, special training or certification for prescribing or dispensing, dispensing only under certain circumstances, special monitoring and the use of patent registries. The FDA may prevent or limit further marketing of a product based on the results of post-market studies or surveillance programs. After approval, many types of changes to the approved product, such as adding new indications, manufacturing changes and additional labeling claims, are subject to further testing requirements and FDA review and approval.

Fast Track, Breakthrough Therapy and Priority Review

The FDA provides programs intended to facilitate and expedite development and review of new products that are intended to address an unmet medical need in the treatment of a serious or life-threatening disease or condition. These programs are referred to as fast track designation, breakthrough therapy designation, and priority review designation. These designations are not mutually exclusive, and a product candidate may qualify for one or more of these programs. While these programs are intended to expedite product development and approval, they do not alter the standards for FDA approval.

The FDA may designate a product for fast track designation if it is intended, whether alone or in combination with one or more other products, for the treatment of a serious or life-threatening disease or condition, and it demonstrates the potential to address unmet medical needs for such a disease or condition. For products with fast track designation, sponsors may have greater interactions with the FDA, the product is potentially eligible for accelerated approval and priority review, if relevant criteria are met, and the FDA may initiate review of sections of a product with fast track designation application before the application is complete. This rolling review may be available if the FDA determines, after preliminary evaluation of clinical data submitted by the sponsor, that a product with fast track designation may be effective. The sponsor must also provide, and the FDA must approve, a schedule for the submission of the remaining information and the sponsor must pay applicable user fees. However, the FDA’s time period goal for reviewing a fast track application does not begin until the last section of the application is submitted. In addition, the fast track designation may be withdrawn by the FDA if the FDA believes that the designation is no longer supported by data emerging in the clinical trial process.

A product may be designated as a breakthrough therapy if it is intended, either alone or in combination with one or more other products, to treat a serious or life-threatening disease or condition and preliminary clinical evidence indicates that the product may demonstrate substantial improvement over existing therapies on one or more clinically significant endpoints, such as substantial treatment effects observed early in clinical development. The FDA may take certain actions with respect to breakthrough therapies, including holding meetings with the sponsor throughout the development process; providing timely advice to the product sponsor regarding development and approval; involving senior managers in the review process; assigning a cross-disciplinary lead for the review team; and taking other steps to design the clinical trials in an efficient manner. Breakthrough designation may be rescinded if a product no longer meets the qualifying criteria.

The FDA may designate a product for priority review if it is a product that treats a serious condition and, if approved, would provide a significant improvement in safety or effectiveness. The FDA determines, on a case-by-case basis, whether the proposed product represents a significant improvement when compared with other available therapies. Significant improvement may be illustrated by evidence of increased effectiveness in the treatment of a condition, elimination or substantial reduction of a treatment-limiting adverse reaction, documented enhancement of patient compliance that may lead to improvement in serious outcomes, and evidence of safety and effectiveness in a new subpopulation. A priority review designation is intended to direct overall attention and resources to the evaluation of such applications, and to shorten the FDA’s goal for taking action on a marketing application from ten months to six months. Priority review designation may be rescinded if a product no longer meets the qualifying criteria.

Accelerated Approval Pathway

The FDA may grant accelerated approval to a product for a serious or life-threatening condition that provides meaningful therapeutic advantage to patients over existing treatments based upon a determination that the product has an effect on a surrogate endpoint that is reasonably likely to predict clinical benefit. For the purposes of accelerated approval, a surrogate endpoint is a marker, such as a laboratory measurement, radiographic image, physical sign, or other measure that is thought to predict clinical benefit but is not itself a measure of clinical benefit. The FDA may also grant accelerated approval for such a condition when the product has an effect on an intermediate clinical endpoint that can be measured earlier than an effect on irreversible morbidity or mortality (IMM), and that is reasonably likely to predict an effect on IMM or other clinical benefit, taking into account the severity, rarity or prevalence of the condition and the availability or lack of alternative treatments. The FDA has limited experience with accelerated approvals based on intermediate clinical endpoints but has indicated that such endpoints generally may support accelerated approval where the therapeutic effect measured by the endpoint is not itself a clinical benefit and basis for traditional approval, if there is a basis for concluding that the therapeutic effect is reasonably likely to predict the ultimate clinical benefit of a product. Products granted accelerated approval must meet the same statutory standards for safety and effectiveness as those granted traditional approval.

The accelerated approval pathway is most often used in settings in which the course of a disease is long, and an extended period of time is required to measure the intended clinical benefit of a product, even if the effect on the surrogate or intermediate clinical endpoint occurs rapidly. Thus, accelerated approval has been used extensively in the development and approval of products for treatment of a variety of cancers in which the goal of therapy is generally to improve survival or decrease morbidity and the duration of the typical disease course requires lengthy and sometimes large trials to demonstrate a clinical or survival benefit.

The accelerated approval pathway is usually contingent on a sponsor’s agreement to conduct, in a diligent manner, additional post-approval confirmatory studies to verify and describe the product’s clinical benefit. As a result, a product candidate approved on this basis is subject to rigorous post-marketing compliance requirements, including the completion of Phase 4 or post-approval clinical trials to confirm the effect on the clinical endpoint. Under the Food and Drug Omnibus Reform Act of 2022 (FDORA) the FDA is now permitted to require, as appropriate, that such trials be underway prior to approval or within a specific time period after the date of approval for a product granted accelerated approval. Sponsors are also required to send updates to the FDA every 180 days on the status of such studies, including progress toward enrollment targets, and the FDA must promptly post this information publicly. Under FDORA, the FDA has increased authority for expedited procedures to withdraw approval of a drug or indication approved under accelerated approval if, for example, the sponsor fails to conduct such studies in a timely manner and send the necessary updates to the FDA, or if a confirmatory trial fails to verify the predicted clinical benefit of the product. In addition, for products being considered for accelerated approval, the FDA generally requires, unless otherwise informed by the agency, that all advertising and promotional materials intended for dissemination or publication within 120 days of marketing approval be submitted to the agency for review during the pre-approval review period.

Orphan Drug Designation

Orphan drug designation in the United States is designed to encourage sponsors to develop products intended for treatment of rare diseases or conditions. In the United States, a rare disease or condition is statutorily defined as a condition that affects fewer than 200,000 individuals in the United States or that affects 200,000 or more individuals in the United States and for which there is no reasonable expectation that the cost of developing and making available the biologic for the disease or condition will be recovered from sales of the product in the United States.

Orphan drug designation qualifies a company for tax credits and market exclusivity for seven years following the date of the product’s marketing approval if granted by the FDA. An application for designation as an orphan product can be made any time prior to the filing of an application for approval to market the product. After the FDA grants orphan designation, the product must then go through the review and approval process like any other product.

A sponsor may request orphan drug designation of a previously unapproved product or new orphan indication for an already marketed product. In addition, a sponsor of a product that is otherwise the same product as an already approved orphan drug may seek and obtain orphan drug designation for the subsequent product for the same rare disease or condition if it can present a plausible hypothesis that its product may be clinically superior to the first drug. More than one sponsor may receive orphan drug designation for the same product for the same rare disease or condition, but each sponsor seeking orphan drug designation must file a complete request for designation.

If a product with orphan designation receives the first FDA approval for the disease or condition for which it has such designation or for a select indication or use within the rare disease or condition for which it was designated, the product generally will receive orphan drug exclusivity. Orphan drug exclusivity means that the FDA may not approve

another sponsor’s marketing application for the same product for the same indication for seven years, except in certain limited circumstances. If a product designated as an orphan drug ultimately receives marketing approval for an indication broader than what was designated in its orphan drug application, it may not be entitled to exclusivity.

The period of exclusivity begins on the date that the marketing application is approved by the FDA and applies only to the indication for which the product has been designated. The FDA may approve a second application for the same product for a different use or a second application for a clinically superior version of the product for the same use. The FDA cannot, however, approve the same product made by another manufacturer for the same indication during the market exclusivity period unless it has the consent of the sponsor, or the sponsor is unable to provide sufficient quantities.

Pediatric Exclusivity

Pediatric exclusivity is another type of non-patent marketing exclusivity in the United States and, if granted, provides for the attachment of an additional six months of marketing protection to the term of any existing regulatory exclusivity, including orphan exclusivity, for all formulations, dosage forms, and indications of the active moiety and, for drugs, patent terms. This six-month exclusivity may be granted if an NDA or BLA sponsor submits pediatric data that in accordance with an FDA-issued written request from the FDA for such data, provided that at the time pediatric exclusivity is granted there is not less than nine months of term remaining. The data do not need to show the product to be effective in the pediatric population studied; rather, if the clinical trial is deemed to fairly respond to the FDA’s request, the additional protection is granted. If reports of requested pediatric studies are submitted to and accepted by the FDA within the statutory time limits, whatever statutory or regulatory periods of exclusivity that cover the product are extended by six months.

U.S. Patent Term Restoration and Extension and Marketing Exclusivity

In the United States, a patent claiming a new biologic product, its method of use or its method of manufacture may be eligible for a limited patent term extension under the Hatch-Waxman Act, which permits a patent extension of up to five years for patent term lost during product development and FDA regulatory review. Assuming grant of the patent for which the extension is sought, the restoration period for a patent covering a product is typically one-half the time between the effective date of the IND and the submission date of the NDA or BLA, plus the time between the submission date of the NDA or BLA and the ultimate approval date, except that the review period is reduced by any time during which the applicant failed to exercise due diligence. Patent term restoration cannot be used to extend the remaining term of a patent past a total of 14 years from the product’s approval date in the United States. Only one patent applicable to an approved product is eligible for the extension, and the application for the extension must be submitted prior to the expiration of the patent for which extension is sought. A patent that covers multiple products for which approval is sought can only be extended in connection with one of the approvals. The USPTO reviews and approves the application for any patent term extension in consultation with the FDA.

Marketing exclusivity provisions under the FDCA also can delay the submission or the approval of certain applications. The FDCA provides a five-year period of non-patent marketing exclusivity within the United States to the first applicant to gain approval of an NDA for a new chemical entity. A drug is a new chemical entity if the FDA has not previously approved any other new drug containing the same active moiety, which is the molecule or ion responsible for the action of the drug substance. During the exclusivity period, the FDA may not accept for review an abbreviated new drug application (ANDA), or a 505(b)(2) NDA submitted by another company for another version of such drug where the applicant does not own or have a legal right of reference to all the data required for approval. However, an application may be submitted after four years if it contains a certification of patent invalidity or non-infringement. The FDCA also provides three years of marketing exclusivity for an NDA, 505(b)(2) NDA or supplement to an existing NDA if new clinical investigations, other than bioavailability studies, that were conducted or sponsored by the applicant are deemed by the FDA to be essential to the approval of the application, for example, new indications, dosages or strengths of an existing drug. This three-year exclusivity covers only the conditions of use associated with the new clinical investigations and does not prohibit the FDA from approving ANDAs for drugs containing the original active agent. Five-year and three-year exclusivity will not delay the submission or approval of a full NDA. However, an applicant submitting a full NDA would be required to conduct or obtain a right of reference to all of the preclinical studies and adequate and well-controlled clinical trials necessary to demonstrate safety and effectiveness.

Biosimilars and Exclusivity

The Patient Protection and Affordable Care Act, as amended by the Health Care and Education Reconciliation Act of 2010 (collectively, the ACA), which was signed into law in March 2010, included a subtitle called the Biologics Price Competition and Innovation Act of 2009 (BPCIA). The BPCIA established a regulatory scheme authorizing the FDA to approve biosimilars and interchangeable biosimilars. A biosimilar is a biological product that is highly similar to an existing FDA-licensed “reference product.” The FDA has issued multiple guidance documents outlining an approach to review and approval of biosimilars. Under the BPCIA, a manufacturer may submit an application for licensure of a biologic product that is “biosimilar to” or “interchangeable with” a previously approved biological product or “reference product.” In order for the FDA to approve a biosimilar product, it must find that there are no clinically meaningful differences between the reference product and proposed biosimilar product in terms of safety, purity and potency. For the FDA to approve a biosimilar product as interchangeable with a reference product, the agency must find that the biosimilar product can be expected to produce the same clinical results as the reference product, and (for products administered multiple times) that the biologic and the reference biologic may be switched after one has been previously administered without increasing safety risks or risks of diminished efficacy relative to exclusive use of the reference biologic.

Under the BPCIA, an application for a biosimilar product may not be submitted to the FDA until four years following the date of approval of the reference product. The FDA may not approve a biosimilar product until 12 years from the date on which the reference product was approved. Even if a product is considered to be a reference product eligible for exclusivity, another company could market a competing version of that product if the FDA approves a full BLA for such product containing the sponsor’s own preclinical data and data from adequate and well-controlled clinical trials to demonstrate the safety, purity and potency of their product. The BPCIA also created certain exclusivity periods for biosimilars approved as interchangeable products. At this juncture, it is unclear whether products deemed “interchangeable” by the FDA will, in fact, be readily substituted by pharmacies, which are governed by state pharmacy law. Since the passage of the BPCIA, many states have passed laws or amendments to laws, including laws governing pharmacy practices, which are state regulated, to regulate the use of biosimilars.

Post-Approval Regulation

If regulatory approval for marketing of a product or new indication for an existing product is obtained, the sponsor will be required to comply with all regular post-approval regulatory requirements as well as any post-approval requirements that the FDA have imposed as part of the approval process. The sponsor will be required to report certain adverse reactions and production problems to the FDA, provide updated safety and efficacy information, and comply with requirements concerning advertising and promotional labeling requirements. Manufacturers and certain of their subcontractors are required to register their establishments with the FDA and certain state agencies and are subject to periodic unannounced inspections by the FDA and certain state agencies for compliance with ongoing regulatory requirements, including cGMP regulations, which impose certain procedural and documentation requirements upon manufacturers, and applicable product tracking and tracing requirements. Accordingly, the sponsor and its third-party manufacturers must continue to expend time, money and effort in the areas of production and quality control to maintain compliance with cGMP regulations and other regulatory requirements.

A biological product may also be subject to official lot release, meaning that the manufacturer is required to perform certain tests on each lot of the product before it is released for distribution. If the product is subject to official lot release, the manufacturer must submit samples of each lot, together with a release protocol showing a summary of the history of manufacture of the lot and the results of all of the manufacturer’s tests performed on the lot, to the FDA. The FDA may in addition perform certain confirmatory tests on lots of some products before releasing the lots for distribution. Finally, the FDA will conduct laboratory research related to the safety, purity, potency and effectiveness of pharmaceutical products.

Once an approval is granted, the FDA may withdraw the approval if compliance with regulatory requirements and standards is not maintained or if problems occur after the product reaches the market. Later discovery of previously unknown problems with a product, including adverse events of unanticipated severity or frequency, or with manufacturing processes, or failure to comply with regulatory requirements, may result in revisions to the approved labeling to add new safety information; imposition of post-market studies or clinical trials to assess new safety risks; or imposition of distribution or other restrictions under a REMS program. Other potential consequences include, among other things:

•restrictions on the marketing or manufacturing of the product;

•complete withdrawal of the product from the market or product recalls;

•fines, warning letters or holds on post-approval clinical trials;

•refusal of the FDA to approve pending applications or supplements to approved applications, or suspension or revocation of product license approvals;

•product recall, seizure or detention, or refusal to permit the import or export of products; or

•injunctions or the imposition of civil or criminal penalties.

The FDA strictly regulates the marketing, labeling, advertising and promotion of prescription drug products placed on the market. This regulation includes, among other things, standards and regulations for direct-to-consumer advertising, communications regarding unapproved uses, industry-sponsored scientific and educational activities and promotional activities involving the Internet and social media. Promotional claims about a drug’s safety or effectiveness are prohibited before the drug is approved. After approval, a drug product generally may not be promoted for uses or patient populations that are not approved by the FDA, as reflected in the product’s prescribing information (known as “off-label” use). In the United States, healthcare professionals are generally permitted to prescribe drugs for such off-label uses because the FDA does not regulate the practice of medicine. However, FDA regulations impose rigorous restrictions on manufacturers’ communications, prohibiting the promotion of off-label uses.

If a company, including any agent of the company or anyone speaking on behalf of the company, is found to have promoted off-label uses, the company may become subject to adverse public relations and administrative and judicial enforcement by the FDA, the DOJ, or the Office of the Inspector General of the Department of Health and Human Services, as well as state authorities. This could subject a company to a range of penalties that could have a significant commercial impact, including civil and criminal fines and agreements that materially restrict the manner in which a company promotes or distributes drug products. The federal government has levied large civil and criminal fines against companies for alleged improper promotion and has also requested that companies enter into consent decrees or permanent injunctions under which specified promotional conduct is changed or curtailed.

Federal and State Data Privacy and Security Laws

Under the federal Health Insurance Portability and Accountability Act of 1996 (HIPAA), the U.S. Department of Health and Human Services (HHS), has issued regulations to protect the privacy and security of protected health information (PHI), used or disclosed by covered entities including certain healthcare providers, health plans and healthcare clearinghouses. HIPAA also regulates standardization of data content, codes and formats used in healthcare transactions and standardization of identifiers for health plans and providers. HIPAA, as amended by the Health Information Technology for Economic and Clinical Health Act of 2009 or HITECH, and their regulations, including the final omnibus rule published on January 25, 2013, also imposes certain obligations on the business associates of covered entities that obtain protected health information in providing services to or on behalf of covered entities. In addition to federal privacy regulations, there are a number of state laws governing confidentiality and security of health information that are applicable to our business. In addition to possible federal administrative, civil and criminal penalties for HIPAA violations, state attorneys general are authorized to file civil actions for damages or injunctions in federal courts to enforce HIPAA and seek attorney’s fees and costs associated with pursuing federal civil actions. Accordingly, state attorneys general have brought civil actions seeking injunctions and damages resulting from alleged violations of HIPAA’s privacy and security rules. New laws and regulations governing privacy and security may be adopted in the future as well.

Additionally, California and numerous other states have recently enacted, or have proposed enacting, comprehensive consumer privacy laws that grant rights to data subjects and place increased privacy and security obligations on entities handling personal data of consumers or households. These laws mark the beginning of a trend toward more stringent privacy legislation in the U.S. and may increase our potential liability as well as adversely affect our business.

Because of the breadth of these laws and the narrowness of the statutory exceptions under such laws, it is possible that some of our current or future business activities, including certain clinical research, sales and marketing practices and the provision of certain items and services to our customers, could be subject to challenge under one or more of such privacy and data security laws. The heightening compliance environment and the need to build and maintain robust and secure systems to comply with different privacy compliance and/or reporting requirements in multiple jurisdictions could increase the possibility that we may fail to comply fully with one or more of these requirements. If our operations are found to be in violation of any applicable privacy or data security laws or regulations, we may be subject to penalties, including potentially significant criminal, civil and administrative penalties, damages, fines, imprisonment, contractual damages, reputational harm, diminished profits and future earnings, additional reporting requirements and/or oversight if we become subject to a consent decree or similar agreement to resolve allegations of non-compliance with these laws, and the curtailment or restructuring of our operations, any of which could adversely affect our ability to operate our business and our results of operations. To the extent that we collect or otherwise process personal information, we may be subject to privacy or data protection laws that are in effect in such third countries foreign laws.

Regulation and Procedures Governing Approval of Medicinal Products Outside the United States

In order to market any product outside of the United States, a company must also comply with numerous and varying regulatory requirements of other countries and jurisdictions regarding quality, safety and efficacy and governing, among other things, clinical trials, marketing authorization, commercial sales and distribution of products. Whether or not it obtains FDA approval for a product, an applicant will need to obtain the necessary approvals by the comparable foreign regulatory authorities before it can commence clinical trials or marketing of the product in those countries or jurisdictions. For example, the process governing approval of medicinal products in the European Union generally follows the same lines as in the United States. It entails satisfactory completion of preclinical studies and adequate and well-controlled clinical trials to establish the safety and efficacy of the product for each proposed indication. It also requires the submission to the relevant competent authorities of a marketing authorization application (MAA) and granting of a marketing authorization by these authorities before the product can be marketed and sold in the European Union.

Clinical Trial Approval

In April 2014, the European Union adopted the new Clinical Trials Regulation (EU) No 536/2014, which came into effect on January 31, 2022 and repealed the Clinical Trials Directive 2001/20/EC. The Clinical Trial Regulation overhauled the previous system of approvals for clinical trials in the European Union. Specifically, the new legislation, which is directly applicable in all EU Member States (meaning no national implementing legislation in each Member State is required), aims at simplifying and streamlining the approval of clinical trials in the European Union, simplifying adverse-event reporting procedures, improving the supervision of clinical trials and increasing their transparency. The main characteristics of the Clinical Trials Regulation include: a streamlined application procedure via a single-entry point through the Clinical Trials Information System (CTIS); a single set of documents to be prepared and submitted for the application as well as simplified reporting procedures for clinical trial sponsors; and a harmonized procedure for the assessment of applications for clinical trials, which is divided in two parts (Part I contains scientific and medicinal product documentation and Part II contains the national and patient-level documentation). Part I is assessed by a coordinated review by the competent authorities of all EU Member States in which an application for authorization of a clinical trial has been submitted (Member States concerned) of a draft report prepared by a Reference Member State. Part II is assessed separately by each Member State concerned. Strict deadlines have been established for the assessment of clinical trial applications. The role of the relevant ethics committees in the assessment procedure continues to be governed by the national law of the applicable Member State, however, overall related timelines are defined by the Clinical Trials Regulation. Parties conducting certain clinical trials must, as in the United States, post clinical trial information in the European Union through the CTIS.

PRIME Designation in the European Union

In March 2016, the EMA launched an initiative to facilitate development of therapeutic candidates in indications, often rare, for which few or no therapies currently exist. The PRIority MEdicines (PRIME), scheme is intended to encourage drug development in areas of unmet medical need and provides accelerated assessment of products representing substantial innovation reviewed under the centralized procedure. Eligible products must target conditions for which there is an unmet medical need (there is no satisfactory method of diagnosis, prevention or treatment in the EU or, if there is, the new medicine will bring a major therapeutic advantage) and they must demonstrate the potential to address the unmet medical need by introducing new methods of therapy or improving existing ones. Products from small- and medium-sized enterprises may qualify for earlier entry into the PRIME scheme than larger companies. Many benefits accrue to sponsors of therapeutic candidates with PRIME designation, including but not limited to, early and proactive regulatory dialogue with the EMA, frequent discussions on clinical trial designs and other development program elements, and accelerated marketing authorisation application (MAA) assessment once a dossier has been submitted. Importantly, a dedicated EMA contact and rapporteur from the Committee for Medicinal Products for Human Use (CHMP), or Committee for Advanced Therapies are appointed early in the PRIME scheme facilitating increased understanding of the product at the EMA’s

Committee level. A kick-off meeting initiates these relationships and includes a team of multidisciplinary experts at the EMA to provide guidance on the overall development and regulatory strategies. Where, during the course of development, a medicine no longer meets the eligibility criteria, support under the PRIME scheme may be withdrawn.

Marketing Authorization

To obtain a marketing authorization for a product under the European Union regulatory system, an applicant must submit an MAA, either under a centralized procedure administered by the EMA or one of the procedures administered by competent authorities in European Union Member States (decentralized procedure, national procedure, or mutual recognition procedure). A marketing authorization may be granted only to an applicant established in the European Union. Regulation (EC) No 1901/2006 provides that prior to obtaining a marketing authorization in the European Union, an applicant must demonstrate compliance with all measures included in an EMA-approved Pediatric Investigation Plan (PIP), covering all subsets of the pediatric population, unless the EMA has granted a product-specific waiver, class waiver or a deferral for one or more of the measures included in the PIP. The Paediatric Committee of the EMA (PDCO), may grant deferrals for some medicines, allowing a company to delay development of the medicine for children until there is enough information to demonstrate its effectiveness and safety in adults. The PDCO may also grant waivers when development of a medicine for children is not needed or is not appropriate, such as for diseases that only affect the elderly population. This requirement also applies when a company wants to add a new indication, pharmaceutical form or route of administration for a medicine that is already authorized. Products that are granted a marketing authorization with the results of the pediatric clinical trials conducted in accordance with the PIP (even where such results are negative) are eligible for six months’ supplementary protection certificate extension. In the case of orphan medicinal products, a two-year extension of the orphan market exclusivity may be available. This pediatric reward is subject to specific conditions and is not automatically available when data in compliance with the PIP are developed and submitted.

The centralized procedure provides for the grant of a single marketing authorization by the European Commission that is valid for all European Union Member States and in the additional Member States of the European Economic Area (EEA) (i.e. Iceland, Liechtenstein and Norway). Pursuant to Regulation (EC) No. 726/2004, the centralized procedure is compulsory for specific products, including for medicines produced by certain biotechnological processes, products designated as orphan medicinal products, advanced therapy medical products (gene therapy, somatic cell therapy and tissue-engineered medicines) and products with a new active substance indicated for the treatment of HIV, AIDS, cancer, neurodegenerative disorders, diabetes, auto-immune and other immune dysfunctions and viral diseases. The centralized procedure is optional for products containing a new active substance not yet authorized in the European Union, or for products that constitute a significant therapeutic, scientific or technical innovation or which are in the interest of public health in the European Union.

Under the centralized procedure in the European Union, the CHMP established at the EMA is responsible for conducting an initial assessment of a product. The maximum timeframe for the evaluation of an MAA is 210 days, excluding clock stops when additional information or written or oral explanation is to be provided by the applicant in response to questions of the CHMP. Clock stops may extend the timeframe of evaluation of a MAA considerably beyond 210 days. Where the CHMP gives a positive opinion, the EMA provides the opinion together with supporting documentation to the European Commission, who make the final decision to grant a marketing authorization, which is issued within 67 days of receipt of the EMA’s recommendation. Accelerated evaluation may be granted by the CHMP in exceptional cases, when a medicinal product is of major interest from the viewpoint of public health and, in particular, of therapeutic innovation. If the CHMP accepts such a request, the time limit of 210 days will be reduced to 150 days, but it is possible that the CHMP may revert to the standard time limit for the centralized procedure if it determines that it is no longer appropriate to conduct an accelerated assessment.

National MAs, which are issued by the competent authorities of the Member States of the EEA and only cover their respective territory, are available for products not falling within the mandatory scope of the centralized procedure. Where a product has already been authorized for marketing in a Member State of the EEA, this national MA can be recognized in other Member States through the mutual recognition procedure. If the product has not received a national MA in any Member State at the time of application, it can be approved simultaneously in various Member States through the decentralized procedure. Under the decentralized procedure an identical dossier is submitted to the competent authorities of each of the Member States in which the MA is sought, one of which is selected by the applicant as the Reference Member State (RMS). The competent authority of the RMS prepares a draft assessment report, a draft summary of the product characteristics (SmPC), and a draft of the labeling and package leaflet, which are sent to the other Member States (referred to as the Concerned Member States (CMSs)) for their approval. If the CMSs raise no objections, based on a potential serious risk to public health, to the assessment, SmPC, labeling, or packaging proposed by the RMS, the product is subsequently granted a national MA in all the Member States (i.e., in the RMS and the CMSs).

Now that the UK (which comprises Great Britain and Northern Ireland) has left the European Union, Great Britain is no longer be covered by centralized MAs (under the Northern Ireland Protocol, centralized MAs currently continue to be recognized in Northern Ireland). All medicinal products with an existing centralized MA were automatically converted to Great Britain MAs on January 1, 2021. On January 1, 2024, a new international recognition framework was put in place by the MHRA, under which the MHRA may have regard to decisions on the approval of a marketing authorization made by the EMA and certain other regulators when considering an application for a UK marketing authorization.

Regulatory Data Protection in the European Union

In the European Union, innovative medicinal products approved on the basis of a complete and independent data package qualify for eight years of data exclusivity upon marketing authorization and an additional two years of market exclusivity pursuant to Regulation (EC) No 726/2004, as amended, and Directive 2001/83/EC, as amended. Data exclusivity if granted, prevents applicants for authorization of generics or biosimilars of these innovative products from referencing the innovator’s preclinical and clinical trial data contained in the dossier of the reference product when applying for a generic (abbreviated) or biosimilar authorization for a period of eight years from the date on which the reference product was first authorized in the European Union. During the additional two-year period of market exclusivity, a generic or biosimilar MAA can be submitted and authorized, and the innovator’s data may be referenced, but no generic or biosimilar medicinal product can be marketed until the expiration of the market exclusivity. The overall ten-year period will be extended to a maximum of eleven years if, during the first eight years of those ten years, the marketing authorization holder obtains an authorization for one or more new therapeutic indications which, during the scientific evaluation prior to authorization, are held to bring a significant clinical benefit in comparison with existing therapies. Even if a compound is considered to be an innovative medicinal product so that the innovator gains the prescribed period of data exclusivity, another company may market another version of the product if such company obtained marketing authorization based on an MAA with a complete and independent data package of pharmaceutical tests, preclinical tests and clinical trials.

Orphan Drug Designation and Exclusivity

Regulation (EC) No 141/2000 and Regulation (EC) No. 847/2000 provide that a product can be designated as an orphan drug by the European Commission if its sponsor can establish: that the product is intended for the diagnosis, prevention or treatment of (1) a life-threatening or chronically debilitating condition affecting not more than five in ten thousand persons in the European Union when the application is made, or (2) a life-threatening, seriously debilitating or serious and chronic condition in the European Union and that without incentives it is unlikely that the marketing of the drug in the European Union would generate sufficient return to justify the necessary investment in its development. For either of these conditions, the applicant must demonstrate that there exists no satisfactory method of diagnosis, prevention or treatment of the condition in question that has been authorized in the European Union or, if such method exists, the drug product would be of significant benefit to those affected by that condition.

An orphan designation provides a number of benefits, including fee reductions, regulatory assistance and the possibility to apply for a centralized European Union marketing authorization. Marketing authorization for an orphan medical product leads to a ten-year period of market exclusivity being granted following marketing authorization of the orphan medical product. During this market exclusivity period, the EMA the European Commission or the Member States may only grant a marketing authorization to a “similar medicinal product” for the same therapeutic indication if: (i) a second applicant can establish that its product, although similar to the authorized product, is safer, more effective or otherwise clinically superior; (ii) the marketing authorization holder for the authorized product consents to a second orphan medicinal product application; or (iii) the marketing authorization holder for the authorized product cannot supply enough orphan medicinal product. A “similar medicinal product” is defined as a medicinal product containing a similar active substance or substances as contained in an authorized orphan medicinal product, and which is intended for the same therapeutic indication. The market exclusivity period for the authorized therapeutic indication may, however, be reduced to six years if, at the end of the fifth year, it is established that the product no longer meets the criteria for orphan designation because, for example, the product is sufficiently profitable not to justify market exclusivity. Orphan designation must be requested before submitting an application for marketing approval. Orphan designation does not convey any advantage in, or shorten the duration of, the regulatory review and approval process.

Patent Term Extensions in the European Union and Other Jurisdictions

The European Union also provides for patent term extension through supplementary protection certificates (SPCs). The rules and requirements for obtaining a SPC are similar to those in the United States. An SPC may extend the term of a patent for up to five years after its originally scheduled expiration date and can provide up to a maximum of fifteen years of marketing exclusivity for a product. In certain circumstances, these periods may be extended for six additional months if pediatric exclusivity is obtained. Although SPCs are available throughout the European Union, sponsors must apply on a country-by-country basis. Similar patent term extension rights exist in certain other foreign jurisdictions outside the European Union.

Periods of Authorization and Renewals

A marketing authorization has an initial validity for five years, in principle, and it may be renewed after five years on the basis of a re-evaluation of the risk-benefit balance by the EMA (for a centrally authorized product) or by the competent authority of the authorizing Member State (for a nationally authorized product). To that end, the marketing authorization holder must provide the EMA or the competent authority with a consolidated version of the file in respect of quality, safety and efficacy, including all variations introduced since the marketing authorization was granted, at least nine months before the marketing authorization ceases to be valid. Once renewed, the marketing authorization is valid for an unlimited period, unless the European Commission or the competent authority decides, on justified grounds relating to pharmacovigilance, to proceed with one additional five-year renewal period. Any authorization that is not followed by the placement of the product on the European Union market (for a centrally authorized product) or on the market of the authorizing Member State (for a nationally authorized product) within three years after authorization, or if the product is removed from the market for three consecutive years, ceases to be valid (the so-called sunset clause).

Regulatory Requirements After Marketing Authorization

Following approval, the holder of the marketing authorization is required to comply with a range of requirements applicable to the manufacturing, marketing, promotion and sale of the medicinal product, and must adhere in strict compliance with the applicable EU laws, regulations and guidance, including Directive 2001/83/EC, Directive- (EU) 2017/1572, Regulation (EC) No 726/2004 and the European Commission Guidelines for Good Manufacturing Practice. These include compliance with the European Union’s stringent pharmacovigilance or safety reporting rules, pursuant to which post-authorization studies and additional monitoring obligations can be imposed. In addition, the manufacturing of authorized products, for which a separate manufacturer’s license is mandatory, must also be conducted in strict compliance with the EMA’s GMP requirements and comparable requirements of other regulatory bodies in the European Union, which mandate the methods, facilities and controls used in manufacturing, processing and packing of medical products to assure their safety and identity.

Much like the Anti-Kickback Statue prohibition in the United States, the provision of benefits or advantages to physicians to induce or encourage the prescription, recommendation, endorsement, purchase, supply, order or use of medicinal products is also prohibited in the European Union. The provision of benefits or advantages to induce or reward improper performance generally is usually governed by the national anti-bribery laws of European Union Member States, and the Bribery Act 2010 in the UK. Infringement of these laws could result in substantial fines and imprisonment. EU Directive 2001/83/EC, which is the EU Directive governing medicinal products for human use, further provides that, where medicinal products are being promoted to persons qualified to prescribe or supply them, no gifts, pecuniary advantages or benefits in kind may be supplied, offered or promised to such persons unless they are inexpensive and relevant to the practice of medicine or pharmacy. This provision has been transposed into the Human Medicines Regulations 2012 and so remains applicable in the UK despite its departure from the European Union.

Payments made to physicians in certain European Union Member States must be publicly disclosed. Moreover, agreements with physicians often must be the subject of prior notification and approval by the physician’s employer, his or her competent professional organization and/or the regulatory authorities of the individual EU Member States. These requirements are provided in the national laws, industry codes or professional codes of conduct, applicable in the EU Member States. Failure to comply with these requirements could result in reputational risk, public reprimands, administrative penalties, fines or imprisonment.

The aforementioned EU rules are generally applicable in the EEA.

Reform of the Regulatory Framework in the European Union

The European Commission introduced legislative proposals in April 2023 that, if implemented, will replace the current regulatory framework in the European Union for all medicines (including those for rare diseases and for children). The European Commission has provided the legislative proposals to the European Parliament and the European Council for their review and approval. In October 2023, the European Parliament published draft reports proposing amendments to the legislative proposals, which will be debated by the European Parliament. Once the European Commission's legislative proposals are approved (with or without amendment), they will be adopted into European Union law.

Brexit and the Regulatory Framework in the United Kingdom

The UK formally left the European Union on January 31, 2020, and the EU and the UK have concluded a trade and cooperation agreement (TCA) which was provisionally applicable since January 1, 2021 and has been formally applicable since May 1, 2021. The TCA includes specific provisions concerning pharmaceuticals, which include the mutual recognition of GMP, inspections of manufacturing facilities for medicinal products and GMP documents issued, but does not provide for wholesale mutual recognition of UK and EU pharmaceutical regulations. At present, Great Britain has implemented EU legislation on the marketing, promotion and sale of medicinal products through the Human Medicines Regulations 2012 (as amended) (under the Northern Ireland Protocol, the EU regulatory framework currently continues to apply in Northern Ireland). Except in respect of the new EU Clinical Trials Regulation, the regulatory regime in Great Britain therefore largely aligns with EU regulations, however it is possible that these regimes will diverge more significantly in future now that Great Britain’s regulatory system is independent from the EU and the TCA does not provide for mutual recognition of UK and EU pharmaceutical legislation. However, notwithstanding that there is no wholesale recognition of EU pharmaceutical legislation under the TCA, under a new international recognition procedure mentioned above, the MHRA may take into account decisions on the approval of a marketing authorization from the EMA (and certain other regulators) when considering an application for a Great Britain marketing authorization.

On February 27, 2023, the UK government and the European Commission announced a political agreement in principle to replace the Northern Ireland Protocol with a new set of arrangements, known as the “Windsor Framework”. This new framework fundamentally changes the existing system under the Northern Ireland Protocol, including with respect to the regulation of medicinal products in the UK. In particular, the MHRA will be responsible for approving all medicinal products destined for the UK market (i.e., Great Britain and Northern Ireland), and the EMA will no longer have any role in approving medicinal products destined for Northern Ireland. A single UK-wide marketing authorization will be granted by the MHRA for all medicinal products to be sold in the UK, enabling products to be sold in a single pack and under a single authorization throughout the UK. The Windsor Framework was approved by the EU-UK Joint Committee on March 24, 2023, so the UK government and the EU will enact legislative measures to bring it into law. On June 9, 2023, the MHRA announced that the medicines aspects of the Windsor Framework will apply from January 1, 2025.

In addition, once we begin to conduct business in the United Kingdom, we will be subject to stringent data protection laws that are in effect in the United Kingdom. As of January 1, 2021, the United Kingdom’s European Union (Withdrawal) Act 2018 incorporated the GDPR (as it existed on December 31, 2020 but subject to certain UK specific amendments) into UK law, referred to as the UK GDPR. The UK GDPR and the UK Data Protection Act 2018 set out the United Kingdom’s data protection regime, which is independent from but aligned to the European Union’s data protection regime. Non-compliance with the UK GDPR may result in monetary penalties of up to £17.5 million or 4% of worldwide revenue, whichever is higher.

General Data Protection Regulation

Once we begin processing of personal data regarding individuals in the European Union, including personal health data, our activities will be subject to the GDPR. The GDPR is wide-ranging in scope and imposes numerous requirements on companies that process personal data, including requirements relating to ensuring an appropriate legal basis and/or condition applies to the processing of personal data, the processing of sensitive date (such as health data), where required by law obtaining consent of the individuals to whom the personal data relates, providing information to individuals regarding data processing activities, implementing safeguards to protect the security and confidentiality of personal data, providing notification of data breaches, conducting data protection impact assessments for high risk processing and taking certain measures when engaging third-party processors. The GDPR also imposes strict rules on the transfer of personal data to countries outside the European Union, including the United States. Compliance with the GDPR will be a rigorous and time-intensive process that may increase the cost of doing business or require us to change our business practices to ensure full compliance.

Coverage, Pricing and Reimbursement

Significant uncertainty exists as to the coverage and reimbursement status of any therapeutic candidates for which we may seek regulatory approval by the FDA or other government authorities. In the United States and markets in other countries, patients who are prescribed treatments for their conditions and providers performing the prescribed services generally rely on third-party payers to reimburse all or part of the associated healthcare costs. Patients are unlikely to use any therapeutic candidates we may develop unless coverage is provided and reimbursement is adequate to cover a significant portion of the cost of such therapeutic candidates. Even if any therapeutic candidates we may develop are approved, sales of such therapeutic candidates will depend, in part, on the extent to which third-party payers, including government health programs in the United States such as Medicare and Medicaid, commercial health insurers and managed care organizations, provide coverage and establish adequate reimbursement levels for, such therapeutic candidates. The process for determining whether a payer will provide coverage for a product may be separate from the process for setting the price or reimbursement rate that the payer will pay for the product once coverage is approved. Third-party payers are increasingly challenging the prices charged, examining the medical necessity, and reviewing the cost-effectiveness of medical products and services and imposing controls to manage costs. Third-party payers may limit coverage to specific products on an approved list, also known as a formulary, which might not include all of the approved products for a particular indication. For more information, see “Risks Related to Commercialization of Our Therapeutic Candidates”.

In order to secure coverage and reimbursement for any product that might be approved for sale, a company may need to conduct expensive pharmacoeconomic studies in order to demonstrate the medical necessity and cost-effectiveness of the product, in addition to the costs required to obtain FDA or other comparable marketing approvals. Nonetheless, therapeutic candidates may not be considered medically necessary or cost effective. A decision by a third-party payer not to cover any therapeutic candidates we may develop could reduce physician utilization of such therapeutic candidates once approved and have a material adverse effect on our sales, results of operations and financial condition. Additionally, a payer’s decision to provide coverage for a product does not imply that an adequate reimbursement rate will be approved. Further, one payer’s determination to provide coverage for a product does not assure that other payers will also provide coverage and reimbursement for the product, and the level of coverage and reimbursement can differ significantly from payer to payer. Third-party reimbursement and coverage may not be available to enable us to maintain price levels sufficient to realize an appropriate return on our investment in product development. In addition, any companion diagnostic tests require coverage and reimbursement separate and apart from the coverage and reimbursement for their companion pharmaceutical or biological products. Similar challenges to obtaining coverage and reimbursement, applicable to pharmaceutical or biological products, will apply to any companion diagnostics.

The containment of healthcare costs also has become a priority of federal, state and foreign governments and the prices of pharmaceuticals have been a focus in this effort. Governments have shown significant interest in implementing cost-containment programs, including price controls, restrictions on reimbursement and requirements for substitution of generic products. Adoption of price controls and cost-containment measures, and adoption of more restrictive policies in jurisdictions with existing controls and measures, could further limit a company’s revenue generated from the sale of any approved products. Coverage policies and third-party reimbursement rates may change at any time. Even if favorable coverage and reimbursement status is attained for one or more products for which a company or its collaborators receive marketing approval, less favorable coverage policies and reimbursement rates may be implemented in the future.

Outside the United States, ensuring adequate coverage and payment for any therapeutic candidates we may develop will face challenges. Pricing of prescription pharmaceuticals is subject to governmental control in many countries. Pricing negotiations with governmental authorities can extend well beyond the receipt of regulatory marketing approval for a product and may require us to conduct a clinical trial that compares the cost effectiveness of any therapeutic candidates we may develop to other available therapies. The conduct of such a clinical trial could be expensive and result in delays in our commercialization efforts.

In the European Union, pricing and reimbursement schemes vary widely from country to country. Some countries provide that products may be marketed only after a reimbursement price has been agreed. Some countries may require the completion of additional studies that compare the cost-effectiveness of a particular product candidate to currently available therapies (so-called health technology assessments) in order to obtain reimbursement or pricing approval. For example, the European Union provides options for its Member States to restrict the range of products for which their national health insurance systems provide reimbursement and to control the prices of medicinal products for human use. European Union Member States may approve a specific price for a product or it may instead adopt a system of direct or indirect controls on the profitability of the company placing the product on the market. Other Member States allow companies to fix their own prices for products but monitor and control prescription volumes and issue guidance to physicians to limit prescriptions. Recently, many countries in the European Union have increased the amount of discounts required on pharmaceuticals and these efforts could continue as countries attempt to manage healthcare expenditures, especially in light of the severe fiscal and debt crises experienced by many countries in the European Union. The downward pressure on healthcare costs in general, particularly prescription products, has become intense. As a result, increasingly high barriers are being erected to the entry of new products. Political, economic and regulatory developments may further complicate pricing negotiations and pricing negotiations may continue after reimbursement has been obtained. Reference pricing used by various European Union Member States, and parallel trade (arbitrage between low-priced and high-priced Member States), can further reduce prices. There can be no assurance that any country that has price controls or reimbursement limitations for pharmaceutical products will allow favorable reimbursement and pricing arrangements for any of our products, if approved in those countries.

Healthcare Law and Regulation

Pharmaceutical companies are subject to additional healthcare regulation and enforcement by the federal government and by authorities in the states and foreign jurisdictions in which they conduct their business that may constrain the financial arrangements and relationships through which we research, as well as sell, market and distribute any products for which we obtain marketing authorization. Such laws include, without limitation, state and federal anti-kickback, fraud and abuse, false claims, and transparency laws and regulations related to drug pricing and payments and other transfers of value made to physicians and other healthcare providers. If our operations are found to be in violation of any such laws or any other governmental regulations that apply, we may be subject to penalties, including, without limitation, administrative, civil and criminal penalties, damages, fines, disgorgement, the curtailment or restructuring of operations, integrity oversight and reporting obligations, exclusion from participation in federal and state healthcare programs and responsible individuals may be subject to imprisonment. For more information, see “Risks Related to Our Business Operations and Industry”.

Healthcare Reform

A primary trend in the U.S. healthcare industry and elsewhere is cost containment. There have been a number of federal and state proposals during the last few years regarding the pricing of pharmaceutical and biopharmaceutical products, limiting coverage and reimbursement for drugs and other medical products, government control and other changes to the healthcare system in the United States. For more information, see “Risks Related to Our Business Operations and Industry”.

The continuing efforts of the government, insurance companies, managed care organizations and other payers of healthcare services to contain or reduce costs of healthcare may adversely affect:

•the demand for any of our product candidates, if approved;

•the ability to set a price that we believe is fair for any of our product candidates, if approved;

•our ability to generate revenues and achieve or maintain profitability;

•the level of taxes that we are required to pay; and

•the availability of capital.

We expect that additional United States federal healthcare reform measures will be adopted in the future, any of which could limit the amounts that the United States federal government will pay for healthcare drugs and services, which could result in reduced demand for our drug candidates or additional pricing pressures. Individual states in the United States have also become increasingly active in passing legislation and implementing regulations designed to control pharmaceutical and biological product pricing, including price or patient reimbursement constraints, discounts, restrictions on certain drug access and marketing cost disclosure and transparency measures, and designed to encourage importation from other countries and bulk purchasing. Legally mandated price controls on payment amounts by third-party payors or other restrictions could harm our business, financial condition, results of operations and prospects. In addition, regional healthcare authorities and individual hospitals are increasingly using bidding procedures to determine what pharmaceutical products and which suppliers will be included in their prescription drug and other healthcare programs. This could reduce the ultimate demand for our drugs or put pressure on our drug pricing, which could negatively affect our business, financial condition, results of operations and prospects.

Human Capital Resources

As of March 6, 2024, we had 159 full-time employees, including a total of 75 employees with doctoral degrees or above. Of these full-time employees, 126 employees are engaged in research and development. None of our employees are represented by labor unions or covered by collective bargaining agreements. We consider our relationship with our employees to be good.

Our human capital resources objectives include, as applicable, identifying, recruiting, retaining, incentivizing and integrating our existing and new employees. The principal purposes of our equity and cash incentive plans are to attract, retain and reward personnel, whether existing employees or new hires, through the granting of stock-based and cash-based compensation awards. We believe that this increases value to our stockholders and the success of our company by motivating such individuals to perform to the best of their abilities and achieve our objectives.

We have, since our inception, worked to create a high-performing, inclusive and diverse workforce, which is a core element of our operating culture. We have deliberately sought to secure top talent with a diversity of thought, experiences and backgrounds who are committed to making a difference in the lives of patients, their families and caregivers. We believe that, by embracing differences, we have a unique advantage in challenging the status quo to apply innovative thinking to long-existing medical challenges. As of March 6, 2024, our workforce was self-reportedly approximately 56% women and approximately 52% Asian, Hispanic, Latino, Black or African American, and women or minorities made up 50% of our senior leadership, reflecting the workforce we strive to create throughout the company.

As the success of our business is fundamentally connected to the well-being of our employees, we are committed to their health, safety and wellness. We provide our employees and their families with access to convenient health and wellness programs, including benefits that provide protection and security giving them peace of mind concerning events that may require time away from work or that impact their financial well-being; and that offer choices where possible so they can customize their benefits to meet their needs and the needs of their families.

Available Information

We maintain an internet website at www.entradatx.com and make available free of charge through our website our Annual Reports on Form 10-K, Quarterly Reports on Form 10-Q, Current Reports on Form 8-K, including exhibits and amendments to those reports filed or furnished pursuant to Sections 13(a) and 15(d) of the Exchange Act of 1934, or the Exchange Act. We make these reports available through our website as soon as reasonably practicable after we electronically file such reports with, or furnish such reports to, the SEC. You can review our electronically filed reports and other information that we file with the SEC on the SEC’s web site at http://www.sec.gov. We also make available, free of charge on our website, the reports filed with the SEC by our executive officers, directors and 10% stockholders pursuant to Section 16 under the Exchange Act as soon as reasonably practicable after copies of those filings are provided to us by those persons. In addition, we regularly use our website to post information regarding our business, product development programs and governance, and we encourage investors to use our website, particularly the information in the section entitled “Investor Relations,” as a source of information about us.

The information on our website is not incorporated by reference into this Annual Report on Form 10-K and should not be considered to be a part of this Annual Report on Form 10-K. Our website address is included in this Annual Report on Form 10-K as an inactive technical reference only.

Note Regarding Trademarks

We have applied for various trademarks that we use in connection with the operation of our business. This Annual Report may also contain trademarks, service marks and trade names of third parties, which are the property of their respective owners. Our use or display of third parties’ trademarks, service marks, trade names or products in this Annual Report is not intended to, and does not imply a relationship with, or endorsement or sponsorship by us. Solely for convenience, the trademarks, service marks and trade names referred to in this Annual Report may appear without the ®, TM or SM symbols, but the omission of such references is not intended to indicate, in any way, that we will not assert, to the fullest extent under applicable law, our rights or that the applicable owner of these trademarks, service marks and trade names will not assert, to the fullest extent under applicable law, its rights.