PepGen Inc.

Previous wording

Investing in our common stock involves a high degree of risk. You should carefully read and consider all of the risks described below, as well as the other information in this 10-K, including our financial statements and the related notes and the section titled “Management’s Discussion and Analysis of Financial Condition and Results of Operations,” and in other documents we file with the SEC when evaluating our business. The occurrence of any of the events or developments described below could harm our business, financial condition, results of operations and growth prospects. Unless otherwise indicated, references to our business being harmed in these risk factors will include harm to our business, reputation, financial condition, results of operations and future prospects. In such an event, the market price of our common stock could decline, and you may lose all or part of your investment. The risks described below are not intended to be exhaustive and are not the only risks that we face. Additional risks and uncertainties not presently known to us or that we currently deem immaterial also may impair our business operations and the market price of our common stock.

Current wording

Investing in our common stock involves a high degree of risk. You should carefully read and consider all of the risks described below, as well as the other information in this Form 10-K, including our financial statements and the related notes and the section titled “Management’s Discussion and Analysis of Financial Condition and Results of Operations,” and in other documents we file with the SEC when evaluating our business. The occurrence of any of the events or developments described below could harm our business, financial condition, results of operations and growth prospects. Unless otherwise indicated, references to our business being harmed in these risk factors will include harm to our business, reputation, financial condition, results of operations and future prospects. In such an event, the market price of our common stock could decline, and you may lose all or part of your investment. The risks described below are not intended to be exhaustive and are not the only risks that we face. Additional risks and uncertainties not presently known to us or that we currently deem immaterial also may impair our business operations and the market price of our common stock.

Previous wording

Since inception, we have incurred significant operating losses. Our net losses were $90.0 million and $78.6 million for the years ended December 31, 2024 and December 31, 2023, respectively. As of December 31, 2024, we had an accumulated deficit of $271.5 million. To date, we have financed our operations primarily with the proceeds raised from the sale of our convertible preferred stock in private placements and common stock in our IPO and our equity offerings in early 2024, described below. We have devoted substantially all of our financial resources and efforts to research and development activities, business planning, establishing and maintaining our intellectual property portfolio, acquiring and developing product and technology rights, hiring personnel, leasing premises and associated capital expenditures, raising capital, and providing general and administrative support for these operations. We are still in the early stages of development of our programs and have only advanced two product candidates into clinical development. We expect to continue to incur significant expenses and operating losses for the foreseeable future. Our operating expenses and net losses may fluctuate significantly from quarter to quarter and year to year. We anticipate that our expenses will increase substantially if and as we:

Current wording

Since inception, we have incurred significant operating losses. Our net losses were $89.7 million and $90.0 million for the years ended December 31, 2025 and December 31, 2024, respectively. As of December 31, 2025, we had an accumulated deficit of $361.1 million. To date, we have financed our operations primarily with the proceeds raised from the sale of our convertible preferred stock in private placements and common stock in our IPO and our equity offerings in 2024 and 2025, described below. We have devoted substantially all of our financial resources and efforts to research and development activities, manufacturing, business planning, establishing and maintaining our intellectual property portfolio, acquiring and developing product and technology rights, hiring personnel, leasing premises and associated capital expenditures, raising capital, and providing general and administrative support for these operations. We are still in the early stages of development of our programs and currently only have one product candidate advancing into clinical development. We expect to continue to incur significant expenses and operating losses for the foreseeable future. Our operating expenses and net losses may fluctuate significantly from quarter to quarter and year to year. We anticipate that our expenses will increase substantially if and as we:

Previous wording

establish manufacturing sources for our product candidates and secure supply chain capacity to provide sufficient quantities for preclinical and clinical development and commercial supply;

Current wording

establish manufacturing sources for our product candidates and secure supply chain capacity to provide sufficient quantities for preclinical and clinical development and commercial supply as well as other CMC activities which support registration, particularly as we scale for an anticipate Phase 3 pivotal trial and look to secure secondary source suppliers for our drug substance;

Previous wording

Even if we obtain regulatory approval of, and are successful in commercializing, one or more of our product candidates, we will continue to incur substantial research and development and other costs to develop and market additional product candidates. We may encounter unforeseen expenses, difficulties, complications, delays and other unknown factors that may adversely affect our business. The size of our future net losses will depend, in part, on the rate of future growth of our expenses and our ability to generate revenue.

Current wording

Even if we obtain regulatory approval of, and are successful in commercializing our product candidate or any future product candidates, we will continue to incur substantial research and development and other costs to develop and market additional product candidates. We may encounter unforeseen expenses, difficulties, complications, delays and other unknown factors that may adversely affect our business. The size of our future net losses will depend, in part, on the rate of future growth of our expenses and our ability to generate revenue.

Previous wording

While we have completed our Phase 1 clinical trial for PGN-EDO51 and initiated two Phase 2 clinical trials for PGN-EDO51 as well as an additional Phase 1 clinical trial for PGN-EDODM1 and more recently, a Phase 2 clinical trial for PGN-EDODM1, we expect that it will be many years, if ever, before we have a product candidate ready for commercialization. In December 2024, the FDA issued a clinical hold on the initiation of our Phase 2 CONNECT2 trial of PGN-EDO51 in DMD in the U.S. It is unknown whether we may be successful in resolving this hold. More recently, Health Canada has requested additional information from us to address safety concerns before any further dose escalation or enrollment of any additional participants at the current dose levels may proceed in our CONNECT1 study of PGN-EDO51. It is unknown whether Health Canada will allow us to dose escalate or enroll additional participants in this study. Moreover, even if we are successful in removing the FDA clinical hold, it is unknown whether the FDA may require the conduct of additional preclinical studies or clinical trials beyond those which we had planned to conduct. To become and remain profitable, we must succeed in developing, obtaining the necessary regulatory approvals for and eventually commercializing a product or products that generate significant revenue. The ability to achieve this success will require us to be effective in a range of challenging activities, including:

Current wording

While we have initiated a Phase 1 and a Phase 2 clinical trial for PGN-EDODM1, we expect that it will be many years, if ever, before we have a product candidate ready for commercialization. All of our other research programs, which are currently paused, are nevertheless in the research or preclinical stage of development, and their risk of failure is therefore particularly high. To become and remain profitable, we must succeed in developing, obtaining the necessary regulatory approvals for and eventually commercializing a product or products that generate significant revenue. The ability to achieve this success will require us to be effective in a range of challenging activities, including:

Previous wording

obtaining marketing approval for our product candidates;

Current wording

obtaining marketing approval for our product candidates, most importantly PGN-EDODM1, including initiating, completing, and funding a large Phase 3 pivotal trial;

Previous wording

We will need to raise substantial additional funding. If we are unable to raise capital when needed, we could be forced to delay, scale back or discontinue our product development programs or future commercialization efforts.

Current wording

We will need to raise substantial additional funding. If we are unable to raise substantial additional funding when needed, we could be forced to delay, scale back or discontinue our product development programs or future commercialization efforts.

Previous wording

We expect our expenses to increase substantially in connection with our ongoing activities, particularly as we identify, continue the research and development of, continue preclinical testing and initiate clinical trials of, arrange for the manufacturing of, and potentially seek marketing approval for any product candidates that successfully completes clinical testing. To date, we have only completed a Phase 1 clinical trial for our first product candidate, PGN-EDO51, initiated one additional Phase 1 clinical trial for PGN-EDODM1, two Phase 2 clinical trials for PGN-EDO51 and more recently, one Phase 2 clinical trial for PGN-EDODM1. The resolution of the clinical hold in the U.S. on the initiation of the Phase 2 CONNECT2 clinical trial of PGN-EDO51, assuming resolution is reached with the FDA, may require additional capital beyond that we had planned to allocate to this program, and the amount of such capital could be considerable. In addition, if we obtain marketing approval for any product candidate, we expect to incur significant commercialization expenses related to product manufacturing, marketing, sales and distribution. Furthermore, we expect to continue to incur additional costs associated with operating as a public company. Accordingly, we will need to obtain substantial additional funding in connection with our continuing operations. If we are unable to raise capital when needed, on attractive terms or at all, we may be forced to delay, reduce or eliminate our research and development programs or future commercialization efforts.

Current wording

We expect our expenses to increase substantially in connection with our ongoing activities, particularly as we identify, continue the research and development of, continue preclinical testing and initiate clinical trials of, arrange for the manufacturing of, and potentially seek marketing approval for our product candidates that successfully complete clinical testing. To date, we have initiated a Phase 1 clinical trial for PGN-EDODM1, and more recently, a Phase 2 clinical trial for PGN-EDODM1. We will require significant additional funding to advance PGN-EDODM1 beyond the initial FREEDOM2 data readouts in 2026 to sustain our operations. We may be unable to raise additional funds, on favorable terms, if at all. If we are unable to raise such capital when needed, we will need to delay, reduce or terminate some or all planned activities to reduce costs and we may be required to initiate steps to cease operations and settle our liabilities. The failure to obtain sufficient additional funds on commercially acceptable terms to fund our operations and satisfy our obligations to creditors may have a material adverse effect on our business, results of operations and financial condition and jeopardize our ability to continue operations in the near-term.

Previous wording

As of December 31, 2024, we had cash, cash equivalents, and marketable securities of $120.2 million. Prior to our IPO in May 2022, we raised aggregate gross proceeds of $133.5 million from the private placement of convertible preferred stock. We raised aggregate gross proceeds of $122.9 million from our IPO.

Current wording

As of December 31, 2025, we had cash, cash equivalents, and marketable securities of $148.5 million. Prior to our IPO in May 2022, we raised aggregate gross proceeds of $133.5 million from the private placement of convertible preferred stock. We raised aggregate gross proceeds of $122.9 million from our IPO. Subsequent to our IPO, in February 2024 we received net proceeds from our ATM program and 2024 Offering, after deducting underwriters' fees and costs of the offerings, of $86.3 million. In September 2025, we completed a public offering, or the 2025 Offering, which resulted in net proceeds of $107.6 million after deducting underwriters' fees and offering expenses.

Previous wording

the scope, progress, costs and results of preclinical and clinical development for our product candidates and any additional product candidates we may develop or any new indications we may pursue;

Current wording

the scope, progress, including continued momentum of enrollment in our FREEDOM2 trial, costs and results of preclinical and clinical development for PGN-EDODM1, including the nature and size of a Phase 3 pivotal trial, and any additional product candidates we may develop or any new indications we may pursue;

Previous wording

the scope, costs, timing and outcome of regulatory review of our product candidates and any additional product candidates we may develop or any new indications we may pursue;

Current wording

the scope, costs, timing and outcome of regulatory review of PGN-EDODM1 and any additional product candidates we may develop or any new indications we may pursue;

Previous wording

the cost and timing of manufacturing activities;

Current wording

the cost and timing of manufacturing activities, particularly as we scale for an anticipated Phase 3 pivotal trial and look to secure secondary source suppliers for our drug substance;

Previous wording

the revenue, if any, received from commercial sales of our product candidates if marketing approval is received;

Current wording

the revenue, if any, received from commercial sales of our clinical stage product candidate if marketing approval is received;

Previous wording

Identifying potential product candidates and conducting preclinical testing and clinical trials are time-consuming, expensive and uncertain processes requiring years to complete, and we may never generate the necessary data or results required to obtain marketing approval and achieve product sales. In addition, even if we successfully develop product candidates and those are approved, we may not achieve commercial success. Our commercial revenues, if any, may not be sufficient to sustain our operations. Accordingly, we will need to continue to rely on additional financing to achieve our business objectives. Adequate additional financing may not be available to us on acceptable terms, or at all.

Current wording

Developing our lead product candidate PGN-EDODM1, identifying other potential product candidates and conducting preclinical testing and clinical trials are time-consuming, expensive and uncertain processes requiring years to complete, and we may never generate the necessary data or results required to obtain marketing approval and achieve product sales. In addition, even if we successfully develop product candidates and those are approved, we may not achieve commercial success. Our commercial revenues, if any, may not be sufficient to sustain our operations. Accordingly, we will need to continue to rely on additional financing to achieve our business objectives. Adequate additional financing may not be available to us on acceptable terms, or at all.

Previous wording

Any additional fundraising efforts may divert our management from their day-to-day activities, which may adversely affect our operations. We cannot be certain that additional funding will be available on acceptable terms, when needed or at all. We have no committed source of additional capital and, if we are unable to raise additional capital in sufficient amounts, when needed or on terms acceptable to us, we may be required to significantly curtail, delay or discontinue one or more of our research or development programs or the commercialization of any product candidate, or be unable to expand our operations or otherwise capitalize on our business opportunities, as desired, which could materially affect our business, financial condition and results of operations. We could be required to seek collaborators for product candidates at an earlier stage than otherwise would be desirable or on terms that are less favorable than might otherwise be available or relinquish or license on unfavorable terms our rights to product candidates in markets where we otherwise would seek to pursue development or commercialization ourselves. Any of the above events could significantly harm our business, prospects, financial condition and results of operations and cause the price of our common stock to decline.

Current wording

Any additional fundraising efforts may divert our management from their day-to-day activities, which may adversely affect our operations. We cannot be certain that additional funding will be available on acceptable terms, when needed or at all. We have no committed source of additional capital and, if we are unable to raise additional capital in sufficient amounts, when needed or on terms acceptable to us, we may be required to significantly curtail, delay or discontinue one or more of our research or development programs, including PGN-EDODM1 or the commercialization of any such product candidate, or be unable to expand our operations or otherwise capitalize on our business opportunities, as desired, and we may be required to initiate steps to cease operations, which could materially affect our business, financial condition and results of operations. We could be required to seek collaborators for product candidates at an earlier stage than otherwise would be desirable or on terms that are less favorable than might otherwise be available or relinquish or license on unfavorable terms our rights to product candidates in markets where we otherwise would seek to pursue development or commercialization ourselves. Any of the above events could significantly harm our business, prospects, financial condition and results of operations and cause the price of our common stock to decline.

Previous wording

We commenced operations in 2018, have no products approved for commercial sale and have not generated any revenue from product sales. To date, our operations have been limited to organizing and staffing our company, business planning, executing collaborations, raising capital, licensing, conducting research activities, conducting preclinical studies of our programs and clinical trials of our product candidates, filing and prosecuting patent applications and providing general and administrative support for these operations. One of our product candidates, PGN-EDO51, completed a Phase 1 clinical trial and we have initiated one additional Phase 1 clinical trial for PGN-EDODM1 and two Phase 2 clinical trials for PGN-EDO51 and more recently, a Phase 2 clinical trial for PGN-EDODM1. In December 2024, the FDA issued a clinical hold on the initiation of our Phase 2 CONNECT2 trial of PGN-EDO51 in DMD in the U.S. It is unknown whether we may be successful in resolving this hold. Moreover, even if we are successful in removing the hold, it is unknown whether the FDA may require the conduct of additional preclinical studies or clinical trials beyond those which we had planned to conduct. More recently, Health Canada has requested additional information from us to address safety concerns before any further dose escalation or enrollment of any additional participants at the current dose levels may proceed in our CONNECT1 Phase 2 study of PGN-EDO51 in DMD. It is unknown whether Health Canada will allow us to dose escalate or enroll additional participants in this study. All of our other research programs are still in the research or preclinical stage of development, and their risk of failure is high. We have not yet demonstrated our ability to successfully complete clinical trials consistently, obtain marketing approvals, manufacture product on a commercial scale or arrange for a third party to do so on our behalf, or conduct sales, marketing and distribution activities necessary for successful product commercialization. Consequently, any predictions you make about our future success or viability may not be as accurate as they could be if we had a longer operating history or a history of successfully developing and commercializing products

Current wording

We commenced operations in 2018, have no products approved for commercial sale and have not generated any revenue from product sales. To date, our operations have been limited to organizing and staffing our company, business planning, executing collaborations, raising capital, licensing, conducting research activities, conducting preclinical studies of our programs and clinical trials of our product candidates, manufacturing drug substance and drug product for our clinical programs, filing and prosecuting patent applications and providing general and administrative support for these operations. We have initiated a Phase 1 clinical trial and a Phase 2 clinical trial for PGN-EDODM1. All of our other research programs are paused and, nevertheless, are in the research or preclinical stage of development, and their risk of failure is high. We have not yet demonstrated our ability to successfully complete clinical trials consistently, obtain marketing approvals, manufacture product on a commercial scale or arrange for a third party to do so on our behalf, or conduct sales, marketing and distribution activities necessary for successful product commercialization.

Previous wording

Our limited operating history may make it difficult to evaluate our technology and industry and predict our future performance. Our limited history as an operating company makes any assessment of our future success or viability subject to significant uncertainty. We will encounter risks and difficulties frequently experienced by early-stage companies in rapidly evolving fields. If we do not address these risks successfully, our business will suffer.

Current wording

Our limited operating history may make it difficult to evaluate our technology and industry and predict our future performance. Our limited history as an operating company makes any assessment of our future success or viability subject to significant uncertainty. We will encounter risks and difficulties frequently experienced by small, early-stage companies in rapidly evolving fields. If we do not address these risks successfully, our business will suffer.

Previous wording

We are early in our development efforts. We have only completed a Phase 1 clinical trial for our lead product candidate and initiated several additional clinical trials, and as a result it will be years before we commercialize a product candidate, if ever. If we are unable to advance our product candidates through preclinical studies and clinical trials, obtain marketing approval and ultimately commercialize them, or experience significant delays in doing so, our business will be materially harmed.

Current wording

We are early in our development efforts, having conducted only two Phase 1 and three Phase 2 clinical trials since our inception and as a result it will be years before we commercialize a product candidate, if ever. If we are unable to advance our product candidates through preclinical studies and clinical trials, obtain marketing approval and ultimately commercialize them, or experience significant delays in doing so, our business will be materially harmed.

Previous wording

We are early in our development efforts and have invested our research efforts to date in developing our EDO platform. We have a portfolio of research programs, and we have two product candidates in clinical trials — PGN-EDO51 for DMD and PGN-EDODM1 for DM1. We have completed a Phase 1 clinical trial for our first product candidate, PGN-EDO51 in HVs. We have initiated our Phase 2 CONNECT1 trial for PGN-EDO51 in Canada and began dosing participants in January of 2024. In July 2024, we reported initial data from the low dose cohort (5 mg/kg) in this trial. Based on this data, we have amended the CONNECT1 study protocol to implement several changes. Following notification of the FDA clinical hold referenced below, Health Canada requested additional information from us to address safety concerns before any further dose escalation or enrollment of any additional participants at the current dose levels may proceed in our CONNECT1 study. It is unknown whether Health Canada will allow us to dose escalate or enroll additional participants in this study. We received clearance from the MHRA to initiate our Phase 2 CONNECT2 trial for PGN-EDO51 in the U.K. In December 2024, the FDA issued a clinical hold on the initiation of the CONNECT2 clinical trial in the U.S. We have initiated a Phase 1 clinical trial, designated FREEDOM, for our second product candidate, PGN-EDODM1, and began dosing participants in December 2023. On February 24, 2025, we reported initial single-dose data for each of the first two cohorts (5 and 10 mg/kg) in the Phase 1 FREEDOM study. We have also opened a Phase 2 clinical trial, FREEDOM2, in Canada and the U.K.

Current wording

We are early in our development efforts and have invested our research efforts to date in developing our EDO platform. We have a portfolio of research programs, and until May 2025, we had two product candidates in clinical trials —PGN-EDODM1 for DM1 and PGN-EDO51 for DMD. We have initiated a Phase 1 clinical trial, designated FREEDOM, for our product candidate, PGN-EDODM1, and began dosing participants in December 2023. We have reported single-dose data for all of the planned cohorts (5, 10 and 15 mg/kg) in the Phase 1 single ascending dose (SAD) FREEDOM study. Based on the positive splicing correction observed and the totality of the safety data, we decided to conclude dose escalation in the FREEDOM trial with the 15 mg/kg cohort. On September 24, 2025, we reported positive initial clinical data for the 15 mg/kg dose level of the FREEDOM study. We have also opened a Phase 2 clinical trial, FREEDOM2, in Canada and the U.K. which has concluded enrollment of the 5 mg/kg cohort, and have began dosing of the 10 mg/kg cohort.

Previous wording

We are evaluating additional product candidates in preclinical studies, but have not completed IND- or CTA-enabling activities for any of our other product candidates or advanced any of our other product candidates into clinical trials. Our ability to generate product revenue, which we do not expect will occur for many years, if ever, will depend heavily on the successful clinical development and eventual commercialization of our product candidates, which may never occur. We currently generate no revenue from sales of any product, and we may never be able to develop or commercialize a marketable product.

Current wording

We are primarily focusing our efforts on the clinical development of PGN-EDODM1 and, accordingly, have not completed IND- or CTA-enabling activities for any other product candidates or advanced any additional product candidates into clinical trials. Our ability to generate product revenue, which we do not expect will occur for many years, if ever, will depend heavily on the successful clinical development and eventual commercialization of our product candidates, which may never occur. We currently generate no revenue from sales of any product, and we may never be able to develop or commercialize a marketable product.

Previous wording

October 2023, we announced that the FDA had lifted the clinical hold, allowing us to initiate FREEDOM in the U.S. Even after initiating FREEDOM in the U.S., the FDA or other regulatory authorities could disagree that we have satisfied their requirements to commence any clinical trial, including our FREEDOM2 study of PGN-EDODM1, or disagree with or change their position on the acceptability of our trial design or the clinical endpoints selected, which may require us to complete additional preclinical studies or clinical trials or impose stricter approval conditions than we currently expect. There are equivalent processes and risks applicable to CTAs in other countries, including Canada and countries in Europe. Moreover, regulatory authorities in other countries could request that we pause dosing or further enrollment in one or more of our ongoing studies based in whole or in part on a clinical hold in the U.S.

Current wording

Commencing clinical trials in the U.S. is subject to authorization by the FDA of an IND and finalizing the trial design based on discussions with the FDA and other regulatory authorities. In the event that the FDA requires us to complete additional preclinical studies, or we are required to satisfy other FDA or other regulator requests prior to commencing clinical trials, the start of our clinical trials may be delayed. For instance, in May 2023, we announced that FDA had placed a clinical hold on our planned Phase 1 FREEDOM clinical trial of PGN-EDODM1 in the U.S. We submitted a response to the FDA and in October 2023, we announced that the FDA had lifted the clinical hold, allowing us to initiate FREEDOM in the U.S. However, we recently received notice of a partial clinical hold from the FDA based on previously submitted preclinical pharmacology and toxicology studies. As part of our ongoing dialogue with the FDA, we are submitting additional analyses, including the recently unblinded Phase 1 FREEDOM data, and are committed to working with the FDA to address their questions as quickly as possible. We may not be able to resolve the issues related to such partial clinical hold in a timely manner, or at all, which may negatively impact the PGN-EDODM1 program, including the FREEDOM2 enrollment timelines. Furthermore, in the future, the FDA or other regulatory authorities could disagree that we have satisfied their requirements to commence any clinical trial, including our FREEDOM2 study of PGN-EDODM1, or disagree with or change their position on the acceptability of our trial design or the clinical endpoints selected, which may require us to complete additional preclinical studies or clinical trials or impose stricter approval conditions than we currently expect. There are equivalent processes and risks applicable to CTAs in other countries, including Canada and countries in Europe. Moreover, regulatory authorities in other countries could request that we pause dosing or further enrollment in one or more of our ongoing studies based in whole or in part on a clinical hold or partial clinical hold in the U.S.

Previous wording

successful initiation, enrollment and completion of clinical trials, including under the FDA’s GCP, GLP, and any additional regulatory requirements from foreign regulatory authorities;

Current wording

successful initiation, enrollment and completion of clinical trials, including under the FDA’s Good Clinical Practice, or GCP, Good Laboratory Practice, and any additional regulatory requirements from foreign regulatory authorities;

Previous wording

Identifying and qualifying patients to participate in clinical trials of our product candidates is critical to our success. We may not be able to identify, recruit and enroll a sufficient number of patients, or those with required or desired characteristics, to complete our clinical trials in a timely manner. Patient enrollment and trial completion is affected by factors including:

Current wording

Identifying and qualifying patients to participate in clinical trials of our product candidates is critical to our success particularly with respect to PGN-EDODM1, which is currently our only clinical development program. We may not be able to identify, recruit and enroll a sufficient number of patients, or those with required or desired characteristics, to complete our clinical trials in a timely manner. Patient enrollment and trial completion is affected by factors including:

Previous wording

For example, DMD amenable to exon 51 skipping is a rare disease, and there are several therapies approved in certain territories or in clinical development, which can make enrollment in our CONNECT1 and CONNECT2 trials more challenging. Our inability to enroll a sufficient number of patients for our clinical trials, including our ongoing trials for PGN-EDO51 and PGN-EDODM1, would result in significant delays and could require us to abandon one or more clinical trials altogether. Enrollment delays in these clinical trials may result in increased development costs for our product candidates, which would cause the value of our company to decline and limit our ability to obtain additional financing. Furthermore, we rely on and expect to continue to rely on CROs and clinical trial sites to ensure the proper and timely conduct of our clinical trials and we will have limited influence over their performance.

Current wording

Our inability to enroll a sufficient number of patients for our clinical trials, including our ongoing FREEDOM2 trial for PGN-EDODM1, would result in significant delays and could require us to abandon one or more clinical trials altogether. Enrollment delays in these clinical trials may result in increased development costs for our product candidates, which would cause the value of our company to decline and limit our ability to obtain additional financing. Furthermore, we rely on and expect to continue to rely on CROs and clinical trial sites to ensure the proper and timely conduct of our clinical trials and we will have limited influence over their performance.

Previous wording

Our lead product candidates are currently in clinical-stage development, while our other product candidates are still in the research or preclinical stage of development and our approach to treating muscle disease is unproven. Our research programs may fail to identify potential product candidates for clinical development for a number of reasons. Our research methodology may be unsuccessful in identifying potential product candidates and our potential product candidates may be shown to have harmful side effects in preclinical in vitro experiments or in vivo animal model studies, or in future clinical studies. In addition, our potential product candidates may not show promising signals of therapeutic effect in such experiments or studies or they may have other characteristics that may make the product candidates impractical to manufacture, unmarketable or unlikely to receive marketing approval. Further, because all of our development programs are based on our EDO platform, adverse developments with respect to one of our programs may have a significant adverse impact on the actual or perceived likelihood of success and value of our other programs. In addition, we may be negatively impacted by the decision of other companies to discontinue development of products using technology similar to our technology. For example, recently, Sarepta announced that it was discontinuing its SRP-5051 peptide-linked PMO development program, based on the risk-benefit of the program, including some patients experiencing hypomagnesemia even after treatment with SRP-5051 was discontinued, feedback from the FDA, and the evolving therapeutic landscape for DMD.

Current wording

Our lead product candidate is currently in clinical-stage development, while other past product candidate programs were in the research or preclinical stage of development. Thus, our approach to treating muscle disease is unproven; for example past efficacy and safety results observed in the PGN-EDODM1 program may not result in a favorable safety profile or efficacy results as future clinical studies readout. In the future, our research programs may fail to identify potential product candidates for clinical development for a number of reasons. Our research methodology may be unsuccessful in identifying potential product candidates and our potential product candidates may be shown to have harmful side effects in preclinical in vitro experiments or in vivo animal model studies, or in future clinical studies. In addition, our potential product candidates may not show promising signals of therapeutic effect in such experiments or studies, as was the case with PGN-EDO51, or they may have other characteristics that may make the product candidates impractical to manufacture, unmarketable or unlikely to receive marketing approval. Further, because all of our development programs are based on our EDO platform, adverse developments with respect to one of our programs may have a significant adverse impact on the actual or perceived likelihood of success and value of our other programs. In addition, we may be negatively impacted by the decision of other companies to discontinue development of products using technology similar to our technology. For example, during 2024, Sarepta Therapeutics, Inc., or Sarepta, announced that it was discontinuing its SRP-5051 peptide-linked phosphorodiamidate morpholino, or PMO, development program, based on the risk-benefit of the program, including some patients experiencing hypomagnesemia even after treatment with SRP-5051 was discontinued, feedback from the FDA, and the evolving therapeutic landscape for DMD.

Previous wording

We have advanced our first two product candidates, PGN-EDO51 and PGN-EDODM1, into the clinic, and have completed a Phase 1 trial of PGN-EDO51 in HVs. However, the positive results we have observed in our preclinical studies and in the completed Phase 1 trial may not be repeated in future clinical trials, including in patients with DMD amenable to an exon-51 skipping approach, and regulatory authorities may disagree with the interpretation of data from our trials.

Current wording

We advanced two product candidates, PGN-EDO51 and PGN-EDODM1, into the clinic, and completed a Phase 1 trial of PGN-EDO51 in healthy volunteers. However, the positive results we observed in our preclinical studies and in the completed Phase 1 trial of PGN-EDO51 were not repeated at the same level in our CONNECT1 Phase 2 clinical trials, and we decided to discontinue development of PGN-EDO51. Accordingly, the results observed in our preclinical and Phase 1 clinical studies of PGN-EDODM1 may not be repeated in our ongoing Phase 2 clinical study. Moreover, regulatory authorities may disagree with the interpretation of data from our trials.

Previous wording

Although we are advancing our initial programs in DMD and DM1, our EDO platform may fail to yield additional product candidates for clinical development for a number of reasons, including those discussed in these risk factors. In addition:

Current wording

Although we are continuing to focus the majority of our efforts on the advancement of our program in DM1, our EDO platform may fail to yield additional product candidates for clinical development for a number of reasons, including those discussed in these risk factors. In addition:

Previous wording

The risk of failure in developing product candidates is high. It is impossible to predict when or if any product candidate would prove effective or safe in humans or will receive regulatory approval. Before obtaining marketing approval from regulatory authorities for the sale of any product candidate, we must complete preclinical development, obtain regulatory clearance to commence clinical trials, and then conduct extensive clinical trials to demonstrate the safety and efficacy of product candidates in humans. To date, we have only completed a Phase 1 clinical trial of PGN-EDO51 and initiated an additional Phase 1 clinical trial of PGN-EDODM1, two Phase 2 clinical trials of PGN-EDO51 and more recently, a Phase 2 clinical trial of PGN-EDODM1.

Current wording

The risk of failure in developing product candidates is high. It is impossible to predict when or if any product candidate would prove effective or safe in humans or will receive regulatory approval. Before obtaining marketing approval from regulatory authorities for the sale of any product candidate, we must complete preclinical development, obtain regulatory clearance to commence clinical trials, and then conduct extensive clinical trials to demonstrate the safety and efficacy of product candidates in humans. To date, we have initiated a Phase 1 clinical trial for PGN-EDODM1, and more recently, a Phase 2 clinical trial for PGN-EDODM1.

Previous wording

Clinical trials may fail to demonstrate that our product candidates are safe for humans and effective for indicated uses, and earlier results, both preclinical and clinical, may not be indicative of future clinical trial results. Even if the clinical trials are successful, changes in marketing approval policies during the development period, changes in or the enactment or promulgation of additional statutes, regulations or guidance, varying interpretations of clinical data or changes in regulatory review for each submitted product application may cause delays in the approval or rejection of an application.

Current wording

Clinical trials may fail to demonstrate that our product candidates are safe for humans and effective for indicated uses, and earlier results, both preclinical and clinical, may not be indicative of future clinical trial results. For example, in the case of PGN-EDO51, our product candidate for DMD, based on the levels of dystrophin protein measured in the 10 mg/kg cohort of CONNECT1, despite a favorable emerging safety profile, we decided to voluntarily discontinue development of PGN-EDO51 and are working to complete the wind-down of DMD-related research and development activities, including our research efforts in DMD relating to exons 44, 45 and 53. Even if our clinical trials are successful, changes in marketing approval policies during the development period, changes in or the enactment or promulgation of additional statutes, regulations or guidance, varying interpretations of clinical data or changes in regulatory review for each submitted product application may cause delays in the approval or rejection of an application.

Previous wording

Before we can commence clinical trials for a product candidate, we must complete extensive preclinical testing and studies that support clearance of our INDs, CTAs and other similar regulatory filings. We cannot be certain if the outcome of our preclinical studies and clinical trials will ultimately support further development of our product candidates or future programs, or future regulatory approval and commercialization. Although we have completed a Phase 1 study of our lead product candidate, PGN-EDO51, initiated two Phase 2 studies of PGN-EDO51 and initiated an additional Phase 1 and a Phase 2 clinical trial of our second candidate, PGN-EDODM1, we cannot be certain of the completion or outcome of our preclinical testing and studies for our other product candidates and cannot predict whether the FDA, European Medicines Agency, or EMA, or comparable foreign regulatory authorities will accept our proposed clinical programs for PGN-EDO51 or PGN-EDODM1, or whether the outcome of our preclinical testing and studies will ultimately support the further development of our other product candidates. For example, Health Canada has recently requested additional information from us to address safety concerns before any further dose escalation or enrollment of any additional participants at the current dose levels may proceed in our Phase 2 CONNECT1 study of PGN-EDO51 in DMD. It is unknown whether Health Canada will allow us to dose escalate or enroll additional participants in this study. In addition, in December 2024, the FDA issued a clinical hold on the initiation of our Phase 2 CONNECT2 trial of PGN-EDO51 in DMD planned to be initiated in the U.S. It is unknown whether we may be successful in resolving this hold. Moreover, even if we are successful in removing the hold, it is unknown whether the FDA may require the conduct of additional preclinical studies or clinical trials beyond those which we are conducting or plan to conduct. Conducting preclinical testing is a lengthy, time-consuming and expensive process. The length of time may vary substantially according to the type, complexity and novelty of the program, and often can be several years or more per program. In addition, the progress and timing of our preclinical studies, including pharmacology and toxicology studies, may be impacted by the limited supply of NHPs needed for such studies. As a result, we cannot be sure that we will be able to submit INDs, CTAs and other similar regulatory filings for our programs on the timelines we expect, if at all, and we cannot be sure that submission of such regulatory filings will result in the FDA, EMA or comparable foreign regulatory authorities allowing clinical trials to begin, including in the case of our CONNECT2 clinical study for PGN-EDO51 and our FREEDOM2 clinical study for PGN-EDODM1. For example, in May 2023, we announced that we received a clinical hold notice from the FDA regarding our IND application to initiate our Phase 1 FREEDOM study, and…

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Current wording

Before we can commence clinical trials for a product candidate, we must complete extensive preclinical testing and studies that support clearance of our INDs, CTAs and other similar regulatory filings. We cannot be certain if the outcome of our preclinical studies and clinical trials will ultimately support further development of our product candidates, as was the case with PGN-EDO51 or future programs, or future regulatory approval and commercialization. Although we have initiated an additional Phase 1 and a Phase 2 clinical trial of our second candidate, PGN-EDODM1, we cannot be certain of the completion or outcome of our preclinical testing and studies for PGN-EDODM1 or any of our other product candidates and cannot predict whether the FDA, or comparable foreign regulatory authorities will accept our proposed clinical program for PGN-EDODM1, or whether the outcome of our preclinical testing and studies will ultimately support the further development of PGN-EODM1 or any other product candidates we may develop. Conducting preclinical testing is a lengthy, time-consuming and expensive process. The length of time may vary substantially according to the type, complexity and novelty of the program, and often can be several years or more per program. In addition, the progress and timing of our preclinical studies, including pharmacology and toxicology studies, may be impacted by the limited supply of NHPs needed for such studies. As a result, we cannot be sure that we will be able to submit INDs, CTAs and other similar regulatory filings for our programs on the timelines we expect, if at all, and we cannot be sure that submission of such regulatory filings will result in the FDA, European Medicines Agency, or EMA, or comparable foreign regulatory authorities allowing clinical trials to begin, including in the case of our FREEDOM2 clinical study for PGN-EDODM1. For example, we recently received notice of a partial clinical hold from the FDA based on previously submitted preclinical pharmacology and toxicology studies. Furthermore, in May 2023, we announced that we received a clinical hold notice from the FDA regarding our IND application to initiate our Phase 1 FREEDOM study, and in June 2023, we provided an update on our plans with respect to this program. In October 2023, we announced that the FDA lifted the clinical hold on our Phase 1 FREEDOM study, allowing this study to proceed in the U.S.

Previous wording

delays in opening clinical trial sites or obtaining required IRB, or independent ethics committee approval, or the equivalent review groups for sites outside the U.S., at each clinical trial site;

Current wording

delays in opening clinical trial sites or obtaining required institutional review board, or IRB, or independent ethics committee approval, or the equivalent review groups for sites outside the U.S., at each clinical trial site;

Previous wording

imposition of a clinical hold by regulatory authorities as a result of a serious adverse event or manufacturing concerns or after an inspection of our clinical trial operations or trial sites;

Current wording

failure of the FDA to remove the recent partial clinical hold on PGN-EDODM1 or the imposition of further clinical holds by regulatory authorities as a result of a serious adverse event or manufacturing concerns or after an inspection of our clinical trial operations or trial sites;

Previous wording

Clinical trials must be conducted in accordance with the FDA and other applicable regulatory authorities’ legal requirements, regulations or guidelines, and are subject to oversight by these governmental agencies and IRBs or ethics committees at the medical institutions where the clinical trials are conducted. We could encounter delays if a clinical trial is suspended or terminated by us, by the DSMB for such trial or by the FDA or any other regulatory authority, or if the IRBs of the institutions in which such trials are being conducted suspend or terminate the participation of their clinical investigators and sites subject to their review. Such authorities may suspend or terminate a clinical trial due to a number of factors, including failure to conduct the clinical trial in accordance with regulatory requirements or our clinical protocols, inspection of the clinical trial operations or trial site by the FDA or other regulatory authorities resulting in the imposition of a clinical hold, unforeseen safety issues or adverse side effects, failure to demonstrate a benefit from using a product candidate, changes in governmental regulations or administrative actions or lack of adequate funding to continue the clinical trial.

Current wording

Clinical trials must be conducted in accordance with the FDA and other applicable regulatory authorities’ legal requirements, regulations or guidelines, and are subject to oversight by these governmental agencies and IRBs or ethics committees at the medical institutions where the clinical trials are conducted. We could encounter delays if a clinical trial is suspended or terminated by us, by the data safety monitoring board for such trial or by the FDA or any other regulatory authority, or if the IRBs of the institutions in which such trials are being conducted suspend or terminate the participation of their clinical investigators and sites subject to their review. Such authorities may suspend or terminate a clinical trial due to a number of factors, including failure to conduct the clinical trial in accordance with regulatory requirements or our clinical protocols, inspection of the clinical trial operations or trial site by the FDA or other regulatory authorities resulting in the imposition of a clinical hold, unforeseen safety issues or adverse side effects, failure to demonstrate a benefit from using a product candidate, changes in governmental regulations or administrative actions or lack of adequate funding to continue the clinical trial.

Previous wording

Any inability to successfully complete preclinical studies and clinical trials could result in additional costs to us or impair our ability to generate revenues from product sales, regulatory and commercialization milestones and royalties. In addition, if we make manufacturing or formulation changes to our product candidates, we may need to conduct additional studies to bridge our modified product candidates to earlier versions. Clinical trial delays also could shorten any periods during which we may have the exclusive right to commercialize our product candidates or allow our competitors to bring products to market before we do, which could impair our ability to successfully commercialize our product candidates and may harm our business, financial condition, results of operations and prospects.

Current wording

Any inability to successfully complete preclinical studies and clinical trials, including in the case of the PGN-EDO51 program, could result in additional costs to us or impair our ability to generate revenues from product sales, regulatory and commercialization milestones and royalties. In addition, if we make manufacturing or formulation changes to our product candidates, we may need to conduct additional studies to bridge our modified product candidates to earlier versions. Clinical trial delays also could shorten any periods during which we may have the exclusive right to commercialize our product candidates or allow our competitors to bring products to market before we do, which could impair our ability to successfully commercialize our product candidates and may harm our business, financial condition, results of operations and prospects.

Previous wording

Further, conducting clinical trials in foreign countries, as we plan to continue to do for our product candidates, presents additional risks that may delay completion of our clinical trials. These risks include the failure of enrolled patients in foreign countries to adhere to clinical protocol as a result of differences in healthcare services or cultural customs, managing additional administrative burdens associated with foreign regulatory schemes, as well as political and economic risks relevant to such foreign countries.

Current wording

Further, conducting clinical trials in foreign countries, as we plan to continue to do for our product candidates, including PGN-EDODM1, presents additional risks that may delay completion of our clinical trials. These risks include the failure of enrolled patients in foreign countries to adhere to clinical protocol as a result of differences in healthcare services or cultural customs, managing additional administrative burdens associated with foreign regulatory schemes, as well as political and economic risks relevant to such foreign countries.

Previous wording

have regulatory authorities withdraw, or suspend, their approval of the product or impose restrictions on its distribution in the form of a REMS;

Current wording

have regulatory authorities withdraw, or suspend, their approval of the product or impose restrictions on its distribution in the form of a Risk Evaluation and Mitigation Strategy, or REMS;

Previous wording

We are in the early stages of our programs and have successfully completed a Phase 1 HV clinical trial in Canada for our lead product candidate, PGN-EDO51, reported early data from the low dose cohort of our first Phase 2 trial of PGN-EDO51 in DMD patients, initiated Phase 1 and Phase 2 clinical trials for our PGN-EDODM1 product candidate and reported initial data from the first two cohorts of our Phase 1 trial of PGN-EDODM1, but we have not completed IND- or CTA-enabling activities for our other product candidates or advanced any other product candidates into clinical development. As a result, our belief in the capabilities of our platform is based on early research, preclinical studies, our completed Phase 1 clinical trial in HVs and early data from our Phase 2 study of PGN-EDO51 and our Phase 1 study of PGN-EDODM1. However, the results of preclinical studies may not be predictive of the results of later preclinical studies or clinical trials, and the results of any early-stage clinical trials may not be predictive of the results of later clinical trials. For example, we may not see the same levels of exon skipping, oligonucleotide delivery or dystrophin production in DMD patients as was observed in our preclinical studies or, with respect to exon skipping and oligonucleotide delivery, in our Phase 1 HV study of PGN-EDO51. While we saw high mean levels of exon skipping (2.15%) in all participants at the 5 mg/kg starting dose of our CONNECT1 Phase 2 study after four doses and three months of treatment, we did not achieve the level of dystrophin that we had anticipated. With a longer treatment period and higher doses of PGN-EDO51, we expect to see higher levels of exon skipped transcript potentially resulting in significant increases in dystrophin, but this may not be the case. Given Health Canada’s recent request for additional information from us to address safety concerns before any further dose escalation or enrollment of any additional participants at the current dose levels may proceed in our CONNECT1 study, we may be unable to further advance the CONNECT1 study beyond dosing of the currently enrolled participants at current dose levels. In addition, with the current clinical hold on initiation of our CONNECT2 clinical trial in the U.S. for PGN-EDO51 in DMD, we may be unable to advance development of PGN-EDO51 for DMD in the U.S. On February 24, 2025, we reported initial single-dose data for each of the first two cohorts (5 and 10 mg/kg) in the Phase 1 FREEDOM study. While we observed robust and dose-dependent mean splicing correction (29.1%) at the 10 mg/kg dose level, we observed limited change in functional outcomes after a single dose over one month. We believe robust splicing correction with PGN-EDODM1 has the potential to lead to meaningful functional improvements with repeat dosing over time, but this may not be the case. Initial success in clinical trials, including in our CONNECT1 and FREEDOM studies, may not be indicative of resul…

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Current wording

We are in the early stages of our programs and have initiated Phase 1 and Phase 2 clinical trials for our PGN-EDODM1 product candidate and reported initial data from three cohorts of our Phase 1 trial of PGN-EDODM1, but we have not completed IND- or CTA-enabling activities advanced any other product candidates (except PGN-EDO51) into clinical development. As a result, our belief in the capabilities of our platform is based on early research, preclinical studies, and early data from our early-stage studies and clinical trials. However, the results of preclinical studies may not be predictive of the results of later preclinical studies or clinical trials, and the results of any early-stage clinical trials may not be predictive of the results of later clinical trials. For example, since PGN-EDO51 did not achieve target dystrophin levels in the CONNECT1 trial, we made the decision to discontinue development of our DMD programs.

Previous wording

From time to time, we may publicly disclose preliminary or topline data from our preclinical studies and clinical trials, which is based on a preliminary analysis of then-available data, and the results and related findings and conclusions are subject to change following a more comprehensive review of the data related to the particular study or trial. For example, in September 2022, we announced results from our Phase 1 clinical trial of PGN-EDO51, in July 2024, we announced initial results from our CONNECT1 Phase 2 trial from the low dose (5 mg/kg) cohort as well as high level safety information for the ongoing 10 mg/kg dose cohort, and more recently, we provided additional safety information from the ongoing CONNECT1 trial. On February 24, 2025, we announced initial results from our FREEDOM Phase 1 trial from the 5 and 10 mg/kg dose cohorts. The topline or preliminary results that we report may differ from future results of the same studies, or different conclusions or considerations may qualify such results, once additional data have been received and fully evaluated. Topline data also remain subject to audit and verification procedures that may result in the final data being materially different from the preliminary data we previously published. As a result, topline data and preliminary results should be viewed with caution until the final data are available.

Current wording

From time to time, we may publicly disclose preliminary or topline data from our preclinical studies and clinical trials, which is based on a preliminary analysis of then-available data, and the results and related findings and conclusions are subject to change following a more comprehensive review of the data related to the particular study or trial. For example, on February 24, 2025, we announced initial results from our FREEDOM Phase 1 trial from the 5 and 10 mg/kg dose cohorts and on September 24, 2025, we announced initial clinical data, including a dose-dependent mean splicing correction (53.7%) at the 15 mg/kg dose level of the ongoing FREEDOM Phase 1, single ascending dose (SAD) study. The topline or preliminary results that we report may differ from future results of the same studies, or different conclusions or considerations may qualify such results, once additional data have been received and fully evaluated. Topline data also remain subject to audit and verification procedures that may result in the final data being materially different from the preliminary data we previously published. As a result, topline data and preliminary results should be viewed with caution until the final data are available. For example, based on preclinical, HV and early data in patients, we believed that with a longer treatment period and higher doses of PGN-EDO51, we could expect to see higher levels of exon skipped transcript potentially resulting in significant increases in dystrophin in our CONNECT1 Phase 2 trial. However, the data from the 10 mg/kg cohort of CONNECT1 demonstrated that PGN-EDO51 did not achieve target dystrophin levels, and we made the decision to discontinue development of our DMD programs.

Previous wording

If any of our product candidates cause undesirable side effects or have other unexpected adverse properties, such side effects or properties could delay or prevent the initiation or completion of clinical trials, regulatory approval, limit the commercial potential or result in significant negative consequences following any potential marketing approval.

Current wording

If PGN-EDODM1, or any of our future product candidates, cause undesirable side effects or have other unexpected adverse properties, such side effects or properties could delay or prevent the initiation or completion of clinical trials prejudice regulatory approval, limit the commercial potential of such candidate or result in significant negative consequences following any potential marketing approval.

Previous wording

Although other oligonucleotide therapeutics have received regulatory approval, ours is a novel approach to oligonucleotide therapy. As a result, there is uncertainty as to the safety profile of our product candidates compared to more well-established classes of therapies, or oligonucleotide therapeutics on their own. Moreover, there have been only a limited number of clinical trials involving the use of peptide conjugated oligonucleotide therapeutics and only one completed trial involving the proprietary technology used in our EDO platform.

Current wording

Undesirable side effects caused by PGN-EDODM1, or future product candidates, could cause us or regulatory authorities to interrupt, delay or halt clinical trials and could result in a more restrictive label or the delay or denial of regulatory approval by the FDA or other regulatory authorities. For instance, we have received notice of a partial clinical hold from the FDA based on previously submitted preclinical pharmacology and toxicology studies. Although other oligonucleotide therapeutics have received regulatory approval, ours is a novel approach to oligonucleotide therapy. As a result, there is uncertainty as to the safety profile of our product candidates compared to more well-established classes of therapies, or oligonucleotide therapeutics on their own. Moreover, there have been only a limited number of clinical trials involving the use of peptide conjugated oligonucleotide therapeutics or our proprietary technology used in our EDO platform.