PepGen Inc.

Previous wording

Since inception, we have incurred significant operating losses. Our net losses were $71.3 million and $67.7 million for the nine months ended September 30, 2025 and September 30, 2024, respectively. As of September 30, 2025, we had an accumulated deficit of $342.8 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, 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 announced in May 2025 that we are focusing our efforts on the development of PGN-EDODM1 and have voluntarily discontinued development of PGN-EDO51. 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 $17.8 million and $30.2 million for the three months ended March 31, 2026 and March 31, 2025, respectively. As of March 31, 2026, we had an accumulated deficit of $378.9 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

continue to advance our PGN-EDODM1 program in DM1 through clinical development, including if enrollment for the FREEDOM2 study takes longer than anticipated;

Current wording

continue to advance our PGN-EDODM1 program in DM1 through clinical development, including if enrollment for the FREEDOM2 study takes longer than anticipated or if we are unable to obtain clearance to initiate sites in additional jurisdictions (such as the US);

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 our product candidate, 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 initiated a 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. We also previously completed a Phase 1 and initiated two Phase 2 clinical trials for PGN-EDO51; however, following our evaluation of the results from the 10 mg/kg cohort in the CONNECT1 trial of PGN-EDO51 in May 2025, we voluntarily decided to discontinue development of PGN-EDO51 and are in the process of winding down all research and development in DMD. All of our other research programs are still 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:

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 are only in the preliminary stages of most of these activities. We may never succeed in these activities and, even if we do, may never generate revenues that are significant enough to achieve profitability. Because of the numerous risks and uncertainties associated with product development, we are unable to accurately estimate or know the nature, timing or costs of the efforts that will be necessary to complete the preclinical and clinical development and commercialization of our product candidates or when, or if, we will be able to generate revenues or achieve profitability.

Current wording

We are only in the preliminary stages of some of these activities. We may never succeed in these activities and, even if we do, may never generate revenues that are significant enough to achieve profitability. Because of the numerous risks and uncertainties associated with product development, we are unable to accurately estimate or know the nature, timing or costs of the efforts that will be necessary to complete the preclinical and clinical development and commercialization of our product candidates or when, or if, we will be able to generate revenues or achieve profitability.

Previous wording

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.

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 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 previously completed a Phase 1 and initiated two Phase 2 clinical trials for PGN-EDO51. However, in May 2025, we voluntarily decided not to continue development of PGN-EDO51 following our evaluation of the results from our CONNECT1 Phase 2 clinical trial and are in the process of winding down all research and development in DMD. We expect to continue to incur expenses to wind down our DMD program through the end of 2025. 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 completed a Phase 1 clinical trial for PGN-EDODM1, and more recently, initiated a Phase 2 clinical trial for PGN-EDODM1.

Previous wording

As of September 30, 2025, we had cash, cash equivalents, and marketable securities of $163.7 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 the 2025 Offering which resulted in net proceeds of $107.6 million after deducting underwriters' fees and estimated offering expenses.

Current wording

As of March 31, 2026, we had cash, cash equivalents, and marketable securities of $132.3 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 follow-on public offering, or the 2025 Offering, which resulted in net proceeds of $107.6 million after deducting underwriters' fees and offering expenses. During the three months ended March 31, 2026, we sold 237,500 shares of common stock under the Sales Agreement resulting in net proceeds of $1.5 million.

Previous wording

the scope, progress, including continued momentum of enrollment in our FREEDOM2 trial, costs and results of preclinical and clinical development for PGN-EDODM1 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 further clinical trials for the development of PGN-EDODM1 such as a Phase 3 pivotal trial, 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

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, 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.

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. We have initiated a Phase 1 clinical trial for PGN-EDODM1, and more recently, a Phase 2 clinical trial for PGN-EDODM1. We previously completed a Phase 1 and initiated two Phase 2 clinical trials for PGN-EDO51. However, in May 2025, we voluntarily decided not to continue development of PGN-EDO51 following our evaluation of the results from our CONNECT1 Phase 2 clinical trial and are in the process of winding down all research and development in DMD. 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 completed a Phase 1 clinical trial and are conducting 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. 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.

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 having conducted only two Phase 1 and three Phase 2 clinical trials since our inception. 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 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 FREEDOM study. Based on the positive splicing correction observed and the totality of the blinded safety data to date, we have 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, 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. We have also opened a Phase 2 clinical trial, FREEDOM2, in Canada and the U.K. All participants in the 5mg/kg cohort have been enrolled and received at least one dose. In May 2025, we announced that based on the levels of dystrophin protein measured in the 10 mg/kg cohort of CONNECT1, we decided to voluntarily discontinue development of our first product candidate, PGN-EDO51, and are in the process of winding down all DMD-related research and development activities, including our research efforts in exon 44, 45 and 53.

Current wording

We are early in our development efforts and have invested our research efforts to date in developing our EDO platform. Until May 2025, we had two product candidates in clinical trials —PGN-EDODM1 for DM1 and PGN-EDO51 for DMD. We initiated a Phase 1 clinical trial, designated FREEDOM, for our product candidate, PGN-EDODM1, in December 2023 which was completed earlier this year. We are also conducting a Phase 2 clinical trial, FREEDOM2, in Canada, the U.K, South Korea, Australia and New Zealand. which has concluded dosing of the 5 mg/kg cohort, and completed enrollment 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

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. As noted above, in December 2024, we announced that FDA had placed a clinical hold on the initiation of our planned Phase 2 CONNECT2 trial in the U.S. In addition, previously, 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. 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, in March 2026, we announced that we 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 submitted 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

If we experience delays or difficulties in the enrollment of patients in clinical trials, our ability to complete clinical trials may be adversely impacted.

Current wording

If we experience delays or difficulties in the enrollment of eligible patients in clinical trials, our ability to complete clinical trials may be adversely impacted.

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 eligible 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

Our inability to enroll a sufficient number of patients for our clinical trials, including our ongoing trials 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.

Current wording

Our inability to enroll a sufficient number of eligible 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

Even if we are able to enroll a sufficient number of patients for our clinical trials, we may have difficulty maintaining patients in our clinical trials. Many of the patients who end up receiving placebo may perceive that they are not receiving the product candidate being tested, and they may decide to withdraw from our clinical trials to pursue other alternative therapies rather than continue the trial with the perception that they are receiving placebo. If we have difficulty enrolling or maintaining a sufficient number of patients to conduct our clinical trials, we may need to delay, limit or terminate clinical trials, any of which would harm our business, financial condition, results of operations and prospects.

Current wording

Even if we are able to enroll a sufficient number of eligible patients for our clinical trials, we may have difficulty maintaining patients in our clinical trials. Many of the patients who end up receiving placebo may perceive that they are not receiving the product candidate being tested, and they may decide to withdraw from our clinical trials to pursue other alternative therapies rather than continue the trial with the perception that they are receiving placebo. If we have difficulty enrolling or maintaining a sufficient number of patients to conduct our clinical trials, we may need to delay, limit or terminate clinical trials, any of which would harm our business, financial condition, results of operations and prospects.

Previous wording

Our lead product candidate is 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, 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.

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 advanced two product candidates, PGN-EDO51 and PGN-EDODM1, into the clinic, and completed a Phase 1 trial of PGN-EDO51 in HVs. 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 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.

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 trial, 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. For instance, although we were encouraged by the trends observed in initial splicing and functional outcome data in the FREEDOM study, in the multi-dose 5 mg/kg cohort of the FREEDOM2 study, the splicing correction results were 7.3% versus 12.7% in the 5 mg/kg cohort of the single dose phase 1 FREEDOM study. Moreover, regulatory authorities may disagree with the interpretation of data from our trials.

Previous wording

Although we are continuing to advance 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:

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 initiated a Phase 1 clinical trial for PGN-EDODM1, and more recently, a Phase 2 clinical trial for PGN-EDODM1. We previously completed a Phase 1 and initiated two Phase 2 clinical trials for PGN-EDO51. However, in May 2025, we voluntarily decided not to continue development of PGN-EDO51 following our evaluation of the results from our CONNECT1 Phase 2 clinical trial and announced our plans to cease all research and development in DMD. We are in the process of winding down all research and development in DMD.

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 completed a Phase 1 clinical trial for PGN-EDODM1, and are conducting 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. For example, as noted above, 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 in the process of winding down all 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.

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, 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, 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.

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 completed a Phase 1 trial and are conducting a Phase 2 clinical trial of our second candidate, PGN-EDODM1, we cannot be certain of the outcome of our preclinical testing, and clinical 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 clinical 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, competent authorities of the EU member states, or comparable foreign regulatory authorities allowing clinical trials to begin, including in the case of our FREEDOM2 clinical study for PGN-EDODM1. For example, in March 2026, we announced that we 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 submitted 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 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

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 partial clinical hold on PGN-EDODM1 or the imposition of further clinical holds by regulatory authorities as a result of a serious adverse events, manufacturing concerns, or after an inspection of our clinical trial operations or trial sites;

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

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 for any earlier stage product candidates or 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.

Current wording

We are in the early stages of our programs and have completed a Phase 1 clinical trial and are conducting a Phase 2 clinical trial for our PGN-EDODM1 product candidate. We reported data from three cohorts of our Phase 1 trial, and from one cohort of our Phase 2 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, 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.

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. 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. Additionally, although we were encouraged by the trends observed in initial splicing and functional outcome data in the FREEDOM study, in the multi-dose 5 mg/kg cohort of the FREEDOM2 study, the splicing correction results were 7.3% versus 12.7% in the 5 mg/kg cohort of the single dose phase 1 FREEDOM study.

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

There may be adverse effects from treatment with any of our current or future product candidates that we cannot predict at this time. Undesirable side effects caused by our current or future product candidates could cause us to interrupt, delay or halt preclinical studies or 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. 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.

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, in March 2026, we announced that we 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.

Previous wording

For example, in our Phase 1 and Phase 2 clinical trials of PGN-EDO51, we observed mild, transient, reversible changes in kidney biomarkers that resolved without intervention in all but one participant who experienced a non-life threatening serious adverse event and transient mild to moderate hypomagnesemia that resolved without intervention or with low-dose oral magnesium supplementation. One participant experienced a reduction of his estimated glomerular filtration rate, or eGFR, that a subsequent nuclear scan indicated was in the normal range. There were no treatment-related SAEs, and all treatment-related adverse events were mild. Despite what we believed to be a favorable emerging safety profile for PGN-EDO51, in May 2025, following a review of the dystrophin data from the 10 mg/kg cohort, we made the voluntary decision to cease development of PGN-EDO51. Additionally, we have reported data from the 5, 10 and 15 mg/kg dose cohorts in our FREEDOM Phase 1 study in DM1 patients. Based on the positive splicing correction observed and the totality of the blinded safety data in the FREEDOM trial to date, we decided to conclude dose escalation in the FREEDOM trial with the 15 mg/kg cohort. Although PGN-EDODM1 was generally well tolerated, we will continue to monitor safety results, including renal biomarker-related AEs, to assess optimal dose in the multi-dose cohorts in FREEDOM2. Given the early stage of clinical development, there can be no assurance that PGN-EDODM1 will not cause undesirable side effects in patients with further dosing and dose escalation, including safety events similar to those observed in our studies with PGN-EDO51.

Current wording

Additionally, in our Phase 1 and Phase 2 clinical trials of PGN-EDO51, we observed mild, transient, reversible changes in kidney biomarkers that resolved without intervention in all but one participant who experienced a non-life threatening serious adverse event and transient mild to moderate hypomagnesemia that resolved without intervention or with low-dose oral magnesium supplementation. One participant experienced a reduction of his estimated glomerular filtration rate, or eGFR, that a subsequent nuclear scan indicated was in the normal range. There were no treatment-related SAEs, and all treatment-related adverse events were mild. Despite what we believed to be a favorable emerging safety profile for PGN-EDO51, in May 2025, following a review of the dystrophin data from the 10 mg/kg cohort, we made the voluntary decision to cease development of PGN-EDO51.

Previous wording

It is possible that, as we test our product candidates in larger, longer and more extensive clinical trials, including with different dosing regimens, or as the use of our product candidates becomes more widespread following any regulatory approval, illnesses, injuries, discomforts and other adverse events that were observed in earlier trials, as well as conditions that did not occur or went undetected in previous trials, will be reported by patients. If such side effects become known later in development or upon approval, if any, such findings may harm our business, financial condition, results of operations and prospects significantly.

Current wording

We may also observe additional safety or tolerability issues in ongoing or future clinical trials as we test our product candidates in larger populations, over longer durations, or with different dosing regimens. Many product candidates that initially showed promise in early-stage testing have later been found to cause side effects that prevented further clinical development. It is possible that, if the use of our product candidates becomes more widespread following any regulatory approval, illnesses, injuries, discomforts and other adverse events that were observed in earlier trials, as well as conditions that did not occur or went undetected in previous trials, will be reported by patients. If such side effects become known later in development or upon approval, if any, such findings may harm our business, financial condition, results of operations and prospects significantly.

Previous wording

Because we have limited financial and managerial resources, we focus on research programs and expect to focus on product candidates that we identify for specific indications among many potential options. As a result, we may forego or delay pursuit of opportunities with other product candidates or for other indications that later prove to have greater commercial potential, or we may choose to focus our efforts and resources on a potential product candidate that ultimately proves to be unsuccessful. Our resource allocation decisions may cause us to fail to capitalize on viable commercial products or profitable market opportunities. Our spending on current and future research and development programs and product candidates for specific indications may not yield any commercially viable medicines. If we do not accurately evaluate the commercial potential or target market for a particular product candidate, we may relinquish valuable rights to that product candidate through collaboration, licensing or other royalty arrangements in cases in which it would have been more advantageous for us to retain sole development and commercialization rights to such product candidate. Any such event could have a material adverse effect on our business, financial condition, results of operations and prospects.

Current wording

Because we have limited financial and managerial resources, we are focusing the majority of our resources on one product candidate, PGN-EDODM1. As a result, we are delaying pursuit of opportunities with other product candidates or for other indications that later prove to have greater commercial potential, or we may choose to focus our efforts and resources on a potential product candidate that ultimately proves to be unsuccessful. Our resource allocation decisions may cause us to fail to capitalize on viable commercial products or profitable market opportunities. Our spending on current and future research and development programs and product candidates for specific indications may not yield any commercially viable medicines. If we do not accurately evaluate the commercial potential or target market for a particular product candidate, we may relinquish valuable rights to that product candidate through collaboration, licensing or other royalty arrangements in cases in which it would have been more advantageous for us to retain sole development and commercialization rights to such product candidate. Any such event could have a material adverse effect on our business, financial condition, results of operations and prospects.

Previous wording

We conduct certain clinical trials for our product candidates outside of the U.S. However, the FDA and comparable foreign regulatory authorities may not accept data from such trials, in which case our development plans will be delayed, which could materially harm our business.

Current wording

We have conducted, and may in the future conduct, certain clinical trials for our product candidates outside of the U.S. However, the FDA and comparable foreign regulatory authorities may not accept data from such trials, in which case our development plans will be delayed, which could materially harm our business.