PDSB 10-K & 10-Q changes, risk factors and insider trading

Our ability to generate revenue and achieve and maintain profitability will depend upon our ability to successfully complete the development of our Versamune® based oncology products Versamune® HPV, PDS0102,PDS0101, PDS0103, alone or in combination with PDS01ADC and Infectimune® to treat infectious diseases and to obtain the necessary regulatory approvals. We have never generated any product revenue and have no immunotherapy candidate in late-stage clinical development or approved for commercial sale.

Even if we receive regulatory approval for the sale of the Versamune®, Versamune® in combination with PDS01ADC and Infectimune® Products, we do not know when we will begin to generate revenue from Versamune® HPVPDS0101 or other products, if at all. Our ability to generate revenue depends on a number of factors, including our ability to:

Because of the numerous risks and uncertainties associated with immunotherapy development and manufacturing, we are unable to predict the timing or amount of increased development expenses, or when we will be able to achieve or maintain profitability, if at all. Our expenses could increase beyond expectations if we are required by the U.S. Food and Drug Administration, or FDA, or comparable non-U.S. regulatory authorities, to perform studies or clinical trials in addition to those we currently anticipate. Even if Versamune® HPVPDS0101 alone or in combination with PDS01ADC is approved for commercial sale, we anticipate incurring significant costs associated with the commercial launch of and the related commercial-scale manufacturing requirements for Versamune® HPV,PDS0101, PDS01ADC, other Versamune® and Infectimune® products. If we cannot successfully execute on any of the factors listed above, above, our business may not succeed, and your investment will be adversely affected.

We have never generated any product revenues and expect to continue to incur substantial and increasing losses as we continue to develop Versamune®, Versamune® in combination with PDS01ADC and Infectimune® based products. None of our products have been approved for marketing in the United States and may never receive such approval. As a result, we are uncertain when or if we will achieve profitability and, if so, whether we will be able to sustain it. Our ability to generate revenue and achieve profitability is dependent on our ability to complete development, obtain necessary regulatory approvals, and have our products manufactured and successfully marketed. We cannot assure you that we will be profitable even if we successfully commercialize Versamune® HPV,PDS0101, PDS01ADC or other Versamune® and Infectimune® based products. If we successfully obtain regulatory approval to market Versamune® HPVPDS0101 alone or in combination with PDS01ADC, our revenues will be dependent, in part, upon, the size of the markets in the territories for which regulatory approval is received, the number of competitors in such markets for the approved indication, and the price at which we can offer our products. If the indication approved by regulatory authorities is narrower than we expect, or the treatment population is narrowed by competition, physician choice or treatment guidelines, we may not generate significant revenue from sales of our products, even if approved. Even if we do achieve profitability, we may not be able to sustain or increase profitability on a quarterly or annual basis. If we fail to become and remain profitable the market price of our common stock and our ability to raise capital and continue operations will be adversely affected.

Versamune® HPVPDS0101 and PDS01ADC are in mid clinical development, and as a consequence, it is too early to determine whether our products will ever be approved for commercial sale or be marketable. We expect that a substantial portion of our efforts and expenditures over the next few years will be devoted to Versamune® and Versamune® in combination with PDS01ADC products. Accordingly, our business currently depends heavily on the successful development, regulatory approval and commercialization of Versamune® HPVPDS0101 alone or in combination with PDS01ADC. Versamune® HPV PDS0101 and PDS01ADC may not receive regulatory approval or be successfully commercialized even if regulatory approval is received. The research, testing, manufacturing, labeling, approval, sale, marketing and distribution of Versamune® HPVPDS0101 and PDS01ADC is and will remain subject to extensive regulation by the FDA and other regulatory authorities in the United States and other countries that each have differing regulations. We are not permitted to market Versamune® HPVPDS0101 or PDS01ADC in the United States until it receives approval of a biologics license application, or BLA, from the FDA, or in any foreign countries until it receives the requisite approval from such countries. To date, we have only completed Phase 2 clinical trials for certain applications of Versamune® HPV.PDS0101. As a result, we have not submitted a BLA to the FDA or comparable applications to other regulatory authorities and do not expect to be in a position to do so for the foreseeable future. Obtaining approval of a BLA is an extensive, lengthy, expensive and inherently uncertain process, and the FDA may delay, limit or deny approval of Versamune® HPVPDS0101 or PDS01ADC for many reasons, including:

We expect to spend substantial amounts to complete the development of, seek regulatory approvals for and commercialize Versamune® HPVPDS0101 alone or in combination with PDS01ADC. Even with our current cash reserves, we will require substantial additional capital to complete the development and potential commercialization of Versamune® HPVPDS0101 and PDS01ADC and the development of other Versamune® and Infectimune® based products. If we are unable to raise capital or find appropriate partnering or licensing collaborations or other nondilutive financing, when needed or on acceptable terms, if at all, we could be forced to delay, reduce or eliminate one or more of our development programs or any future commercialization efforts. In addition, attempting to secure additional financing may divert the time and attention of our management from day-to-day activities and harm our development efforts.

Our estimate as to what we will be able to accomplish is based on assumptions that may prove to be inaccurate, and we could exhaust our available capital resources sooner than is currently expected. Because the length of time and activities associated with successful development of Versamune® HPVPDS0101 and PDS01ADC is highly uncertain, we are unable to estimate the actual funds we will require for development and any approved marketing and commercialization activities. Our future funding requirements, both near and long-term, will depend on many factors, including, but not limited to:

Additional funding may not be available on acceptable terms, or at all. If we are unable to raise additional capital in sufficient amounts or on terms acceptable to us, we may have to significantly delay, scale back or discontinue the development or commercialization of Versamune® HPVPDS0101 or potentially discontinue operations.

If we raise additional funds through collaborations, strategic alliances or marketing, distribution or licensing arrangements with third parties, we may have to relinquish valuable rights to our technologies, future revenue streams, research programs or Versamune® Products or grant licenses on terms that may not be favorable to us. If we are unable to raise additional funds through equity or debt financings when needed, or through collaborations, strategic alliances or marketing, distribution or licensing arrangements with third parties on acceptable terms, we may be required to delay, limit, reduce or terminate our Versamune® HPV PDS0101 and PDS01ADC development or future commercialization efforts or grant rights to develop and market other Versamune® and Infectimune® products that we would otherwise develop and market.

Our operating activities may be restricted as a result of covenants related to the outstanding indebtedness underissued pursuant ourto venturethe loantransactions andcontemplated securityby that certain securities purchase agreement with HorizonJGB, and we may be required to repay the outstanding indebtedness in an event of default, which could have a materially adverse effect on our business.

If we fail to obtain or maintain adequate coverage and reimbursement for Versamune® HPVPDS0101 or PDS01ADC, our ability to generate revenue could be limited.

The availability and extent of reimbursement by governmental and private payors is essential for most patients to be able to afford expensive treatments. Sales of any of Versamune® HPVPDS0101 or PDS01ADC that receive marketing approval will depend substantially, both in the United States and internationally, on the extent to which the costs of Versamune® HPVPDS0101 or PDS01ADC will be paid by health maintenance, managed care, pharmacy benefit and similar healthcare management organizations, or reimbursed by government health administration authorities, private health coverage insurers and other third-party payors. If reimbursement is not available, or is available only on a limited basis, we may not be able to successfully commercialize Versamune® HPVPDS0101 alone or in combination with PDS01ADC. Even if coverage is provided, the approved reimbursement amount may not be high enough to allow us to to establish or maintain adequate pricing that will allow it to realize a sufficient return on our investment.

Outside the United States, international operations are generally subject to extensive governmental price controls and other market regulations, and we believe the increasing emphasis on cost-containment initiatives in Europe, Canada and other countries may cause us to price Versamune® HPVPDS0101 alone or in combination with PDS01ADC on less favorable terms than we currently anticipate. In many countries, particularly the countries of the European Union, the prices of medical products are subject to varying price control mechanisms as part of national health systems. In these countries, pricing negotiations with governmental authorities can take considerable time after the receipt of marketing approval for a product. To obtain reimbursement or pricing approval in some countries, we may be required to conduct a clinical trial that compares the cost-effectiveness of Versamune® HPV PDS0101 or PDS01ADC to other available therapies. In general, the prices of products under such systems are substantially lower than in the United States. Other countries allow companies to fix their own prices for products, but monitor and control company profits. Additional foreign price controls or other changes in pricing regulation could restrict the amount that we are able to charge for Versamune® HPVPDS0101 alone or in combination with PDS01ADC. Accordingly, in markets outside the United States, the reimbursement for our products may be reduced compared with the United States and may be insufficient to generate commercially reasonable revenues and profits.

Moreover, increasing efforts by governmental and third-party payors, in the United States and internationally, to cap or reduce healthcare costs may cause such organizations to limit both coverage and level of reimbursement for newly approved products and, as a result, they may not cover or provide adequate payment for Versamune® HPVPDS0101 or PDS01ADC. We expect to experience pricing pressures in connection with the sale of Versamune® HPVPDS0101 or PDS01ADC due to the trend toward managed healthcare, the increasing influence of health maintenance organizations and additional legislative changes. The downward pressure on healthcare costs in general, particularly prescription drugs and surgical procedures and other treatments, has become very intense. As a result, increasingly high barriers are being erected to the entry of new products into the healthcare market.

The Inflation Reduction Act, referred to as the IRA, was recently signed into law by President Biden, which makes significant changes to how drugs are covered and paid for under the Medicare program, including the creation of financial penalties for drugs whose prices rise faster than the rate of inflation, redesign of the Medicare Part D program to require manufacturers to bear more of the liability for certain drug benefits, and government price-setting for certain Medicare Part D drugs, starting in 2026, and Medicare Part B drugs starting in 2028. We have evaluated, and will continue to evaluate, the effect of the IRA on our business. At this time, we do not not expect the IRA to have a material effect on our financial position.

Our future financial performance and our ability to commercialize Versamune® HPVPDS0101 alone or in combination with PDS01ADC and compete effectively will depend, in part, on our ability to effectively manage any future growth. As of December 31, 2024,2025, we had 2421 employees and 2224 consultants. We expect to hire additional employees for our managerial, clinical, scientific and engineering, operational, manufacturing, sales and marketing teams. We may have operational difficulties in connection with identifying, hiring and integrating new personnel. Future growth would impose significant additional responsibilities on our management, including the need to identify, recruit, maintain, motivate and integrate additional employees, consultants and contractors. Also, our management may need to divert a disproportionate amount of our attention away from our day-to-day activities and devote a substantial amount of time to managing these growth activities. We may not be able to effectively manage the expansion of our operations, which may result in weaknesses in our infrastructure, give rise to operational mistakes, loss of business opportunities, loss of employees and reduced productivity among remaining employees. Our expected growth could require significant capital expenditures and may divert financial resources from other projects, such as the development of Versamune® HPV.PDS0101. If we are unable to effectively manage our growth, our expenses may increase more than expected, our ability to generate and/or grow revenues could be reduced, and we may not be able to implement our business strategy.

Many of the other pharmaceutical companies that we compete against for qualified personnel and consultants have greater financial and other resources, different risk profiles and a longer history in the industry than us. They also may provide more diverse opportunities and better chances for career advancement. Some of these characteristics may be more appealing to high-quality candidates and consultants than what it has to offer. If we are unable to continue to attract and retain high-quality personnel and consultants, the rate and success at which we can select and develop Versamune® HPVPDS0101 or PDS01ADC and our business will be limited.

Our computer systems and those of our service providers, including our CROs, are vulnerable to damage from computer viruses, unauthorized access, natural disasters, terrorism, war and telecommunication and electrical failures. If such an event were to occur and cause interruptions in our or their operations, it could result in a material disruption of our development programs. For example, the loss of preclinical or clinical trial data from completed, ongoing or planned trials could result in delays in our regulatory approval efforts and significantly increase our costs to recover or reproduce the data. To the extent that any disruption or security breach were to result in a loss of or damage to data or applications, or inappropriate disclosure of personal, confidential or proprietary information, we could incur liability and the further development of Versamune® HPV PDS0101 and PDS01ADC could be delayed.

We have incurred net losses and utilized cash in operations since inception. In addition, as of December 31, 2024,2025, we had approximately $41.7$26.7 million in cash and cash equivalents, and during the twelve months ended December 31, 2024,2025, we used $35.0$27.8 million of cash in operations and expect to continue to incur significant cash outflows and incur future additional losses to execute our operating plan. While we intend to finance our cash needs principally through collaborations, strategic alliances, or license agreements with third parties and/or debt or equity financings, there is no assurance that new financing will be available to us on commercially acceptable terms or in the amounts required, if at all. In addition, under the LoanDebentures, we must at all times maintain a cash balance equal to the lesser of (a) $15.0 million and Security Agreement allows for(b) the lendersthen-outstanding to call the outstandingprincipal balance of the termDebentures loansplus $3.0 million, in a deposit account subject to an account control agreement. A breach of any of the covenants under the Debentures, including, without limitation, the cash balance covenant, could result in a default under the Debentures. Upon the occurrence of an event of default under the Debentures, the investors could elect to declare all amounts outstanding, if theany, minimumto cashbe balancesimmediately outlineddue inand payable. If there are any amounts outstanding that we are unable to repay, the Loaninvestors andcould proceed against the SecurityCollateral Agreementgranted areto notit maintained.to secure such indebtedness.. Due to the uncertainty in securing additional funding,funding and the insufficient amount of cash and cash equivalents as of December 31, 2024,2025, we have concluded that substantial doubt exists about our ability to continue as a going concern within one year after the date of the filing of this Annual Report. If we are unsuccessful in securing sufficient financing, we may need to delay, reduce, or eliminate our research and development programs, which could adversely affect our business prospects, or cease operations.

Versamune® HPVPDS0101 and PDS01ADC are still in clinical development and will require additional clinical testing before we are prepared to submit a BLA for regulatory approval for any indication or for any other treatment regime. We cannot predict with any certainty if or when we might submit a BLA for regulatory approval for Versamune® HPV,PDS0101, PDS01ADC and other Versamune® based products or whether any such BLAs will be approved by the FDA. Human clinical trials are very expensive and difficult to design and implement, in part because they are subject to rigorous regulatory requirements. For instance, the FDA may not agree with our proposed endpoints for any clinical trial we propose, which may delay the commencement of our clinical trials. The clinical trial process is also time-consuming. We estimate that the clinical trials we need to conduct to be in a position to submit BLAs for PDS0101 Versamune® HPV alone or in combination with PDS01ADC will take several years to complete. We cannot predict the timeline for review of submissions to any regulatory authorities or when any of our product candidates will receive marketing approval, if at all. all. The timeline for regulatory approval can be affected by a variety of factors, including, budget and funding levels, agency staffing, and statutory, regulatory and policy changes.

Furthermore, failure can occur at any stage of the trials, and we could encounter problems that cause us to abandon or repeat clinical trials. In later stages of clinical trials, Versamune® HPVPDS0101 and PDS01ADC may fail to show the desired safety and efficacy traits despite having progressed through preclinical studies and initial clinical trials, and the results of current clinical trials of Versamune®PDS0101 HPV therefore may not be predictive of the results of our continued or planned Phase 2 and 3 trials. A number of companies in the biopharmaceutical industry have suffered significant setbacks in advanced clinical trials due to lack of efficacy or adverse safety profiles, notwithstanding promising results in earlier stages of clinical trials.

Product development costs will also increase if we experience delays in testing or in receiving marketing approvals. We do not know whether any clinical trials will begin as planned, will need to be restructured or will be completed on schedule, or at all. Significant clinical trial delays also could shorten any periods during which we may have the exclusive right to commercialize Versamune® HPVPDS0101 alone or in combination with PDS01ADC, could allow our competitors to bring products to market before we do, and could impair our ability to successfully commercialize Versamune® HPVPDS0101 or PDS01ADC, any of which may harm our business and results of operations.

We may encounter delays in enrolling, or be unable to enroll, a sufficient number of participants to complete any of our clinical trials. Once enrolled, we may be unable to retain a sufficient number of participants to complete any of our trials. Late-stage clinical trials of Versamune® HPVPDS0101 alone or in combination with PDS01ADC or other agents may require the enrollment and retention of large numbers of subjects. Subject enrollment and retention in clinical trials depends on many factors, including the size of the subject population, the nature of the trial protocol, the existing body of safety and efficacy data with respect to the study drug, the number and nature of competing treatments and ongoing clinical trials of competing drugs for the same indication, patients’ and clinicians’ perceived risks and benefits of the product candidate under study the proximity of subjects to clinical sites and the eligibility criteria for the study.

Furthermore, any negative results we may report in clinical trials of Versamune® HPVPDS0101 and PDS01ADC may make it difficult or impossible to recruit and retain participants in other clinical trials of Versamune® HPV.PDS0101. Delays or failures in planned subject enrollment or retention may result in increased costs, program delays or both, which could have a harmful effect on our ability to develop Versamune® HPV PDS0101 and PDS01ADC, or could render further development impractical. In addition, we expect to rely on CROs and clinical trial sites to ensure proper and timely conduct of our future clinical trials and, while we intend to enter into agreements governing their services, we will be limited in our ability to compel their actual performance in compliance with applicable regulations. Enforcement actions brought against these third parties may cause further delays and expenses related to our clinical clinical development programs.

Successful development of immunotherapies is highly uncertain and is dependent on numerous factors, many of which are beyond our control. Immunotherapies that appear promising in the early phases of development may fail to reach, or be delayed in reaching, the market for several reasons including: preclinical study results that may show the immunotherapy to be less safe or effective than desired (e.g., the study failed to meet its primary objectives) or to have harmful or problematic side effects; clinical study results that may show the immunotherapy to be less effective than expected (e.g., the study failed to meet its primary endpoint) or to have unacceptable side effects; or failure to receive the necessary regulatory approvals or a delay in receiving such approvals. Among other things, such delays may be caused by multiple factors including: slow enrollment in clinical studies, inability to retain study participants, length of time to achieve study endpoints, delays in receiving the necessary products or supplies for the conduct of clinical or preclinical trials, additional time requirements for data analysis, or Biologics License Application preparation, discussions with the FDA, an FDA request for additional preclinical or clinical data, FDA delays in inspecting manufacturing establishments, failure to receive FDA approval for manufacturing processes or facilities, or unexpected safety or manufacturing issues; manufacturing costs, formulation issues, pricing or reimbursement issues, or other factors that make the immunotherapy uneconomical; and the proprietary rights of others and their competing products and technologies that may prevent the immunotherapy from being commercialized. Success in preclinical and early and interim clinical studies does not ensure that large-scale clinical studies will be successful. Clinical results are frequently susceptible to varying interpretations that may delay, limit or prevent regulatory approvals. The length of time necessary to complete clinical studies and to submit an application for marketing approval for a final decision by a regulatory authority varies significantly from one immunotherapy to the next and may be difficult to predict. Even if our product candidates are approved, they may be subject to limitations on the indicatedindications, intended uses and populations for which they may be marketed. They may also be subject to other conditions of approval, may contain significant safety warnings, including boxed warnings, contraindications, and precautions, may not be approved with label statements necessary or desirable for successful commercialization, or may contain requirements for costly post-market testing and surveillance, or other requirements, including the submission of a REMS, to monitor the safety or efficacy of the products. If we do not receive FDA approval for, and successfully commercialize our product candidates, we will not be able to generate revenue from these product candidates in the United States in the foreseeable future, or at all. Any significant delays in obtaining approval for and commercializing our product candidates will have a material adverse impact on our business and financial condition.

The biotechnology and biopharmaceutical industries are characterized by rapid technological developments and a high degree of competition. As a result, Versamune® HPV,PDS0101, PDS01ADC or other Versamune® and Infectimune® based products could become obsolete before we recoup any portion of our related research and development and commercialization expenses. Competition in the biopharmaceutical industry is based significantly on scientific and technological factors. These factors include the availability of patent and other protection for technology and products, the ability to commercialize technological developments and the ability to obtain governmental approval for testing, manufacturing and marketing. We compete with specialized biopharmaceutical firms in the United States, Europe and elsewhere, as well as a growing number of large pharmaceutical companies that are applying biotechnology to their operations. Many biopharmaceutical companies have focused their development efforts in the human therapeutics area, including cancer. Many major pharmaceutical companies have developed or acquired internal biotechnology capabilities or made commercial arrangements with other biopharmaceutical companies. These companies, as well as academic institutions and governmental agencies and private research organizations, also compete with us in recruiting and retaining highly qualified scientific personnel and consultants. Our ability to compete successfully with other companies in the pharmaceutical field will also depend to a considerable degree on the continuing availability of capital to us.

We are aware of certain investigational new drugs under development or approved products by competitors that are used for the prevention, diagnosis, or treatment of certain diseases we have targeted for drug development. Various companies are developing biopharmaceutical products that have the potential to directly compete with Versamune® HPVPDS0101 and PDS01ADC even though their approach to may be different. We believe our top clinical-stage competitors pursuing cancer immunotherapies and/or vaccines for infectious diseases include, but not limited to Merus, F-Star Therapeutics, Genmab, Johnson & Johnson Innovative Medicine (part of Johnson & Johnson), Sanofi-Aventis, GlaxoSmithKline plc, Merck andMerck, Pfizer, Inovio, Kite Pharma, Hookipa, Moderna, ZIOPHARM Oncology, Heat Biologics, Harpoon Therapeutics, BioNTech, Osivax, Medicago, Vaxart, IO Biotech, ExelixisExelixis, Bicara and Flugen. Many of these companies companies have substantially greater financial, marketing, and human resources than we do (including, in some cases, substantially greater experience in clinical testing, manufacturing, and marketing of pharmaceutical products). If one or more of these these companies is successful in developing their technologies, it could materially impact our business. We also experience competition in the development of our immunotherapies from universities and other research institutions and compete with others in acquiring technology from such universities and institutions.

Competition may increase further as a result of advances in the commercial applicability of technologies and greater availability of capital for investment in these industries. Our competitors may succeed in developing, acquiring or licensing, on an exclusive basis, drugs that are more effective or less costly than Versamune® HPV,PDS0101, PDS01ADC or our other Versamune® and Infectimune® based products.

The availability of our competitors’ immunotherapies and other treatments could limit the demand, and the price we are able to charge, for Versamune® HPVPDS0101 alone or in combination with PDS01ADC. The inability to compete with existing or subsequently introduced immunotherapies and other treatments would have an adverse impact on our business, financial condition and prospects.

Established pharmaceutical companies may invest heavily to accelerate discovery and development of novel compounds or to license novel compounds that could make Versamune®PDS0101 HPV and PDS01ADC less competitive. In addition, any new immunotherapy that competes with an approved treatment must demonstrate compelling advantages in efficacy, convenience, tolerability and safety in order to overcome price competition and to be commercially successful. Accordingly, our competitors may succeed in obtaining patent protection, discovering, developing, receiving the FDA’s approval for or commercializing medicines before we do, which would have an adverse impact on our business and results of operations.

Versamune® HPVPDS0101 and PDS01ADC may cause adverse effects or have other properties that could delay or prevent their regulatory approval or limit the scope of any approved label or market acceptance.

Adverse events caused by Versamune® HPVPDS0101 or PDS01ADC could cause reviewing entities, clinical trial sites or regulatory authorities to interrupt, delay or halt clinical trials and could result in the denial of regulatory approval. If clinical trials for Versamune® HPVPDS0101 and PDS01ADC report an unacceptable frequency or severity of adverse events, our ability to obtain regulatory approval for Versamune® HPVPDS0101 and PDS01ADC may be negatively impacted.

Furthermore, if Versamune® HPVPDS0101 alone or in combination with PDS01ADC is approved and then causes serious or unexpected side effects, a number of potentially significant negative consequences could result, including:

Any of these events could prevent us from achieving or maintaining market acceptance of Versamune® HPVPDS0101 and PDS01ADC and could substantially increase the costs of commercialization.

If we are not able to obtain, or if there are delays in obtaining, required regulatory approvals, we will not be able to commercialize, or will be delayed in commercializing, Versamune® HPVPDS0101 and PDS01ADC, and our ability to generate revenue will be impaired.

Versamune® HPVPDS0101 and PDS01ADC and the activities associated with their development and commercialization, including their design, testing, manufacture, safety, efficacy, recordkeeping, labeling, storage, approval, advertising, promotion, sale and distribution, are subject to comprehensive regulation by the FDA and other regulatory agencies in the United States and by comparable authorities in other countries. Failure to obtain marketing approval for Versamune® HPVPDS0101 alone or in combination with PDS01ADC will prevent us from commercializing our products. We have not received approval to market Versamune® HPVPDS0101 or PDS01ADC from regulatory authorities in any jurisdiction. We have only limited experience in filing and supporting the applications necessary to gain marketing approvals and expect to rely on contract research organizations to assist us in this process. Securing regulatory approval approval requires the submission of extensive preclinical and clinical data and supporting information to the various regulatory authorities for each therapeutic indication to establish the safety and efficacy of Versamune® HPVPDS0101 and PDS01ADC. Securing regulatory approval also requires the submission of information about the product manufacturing process, and inspection of manufacturing facilities by, the relevant regulatory authority. Versamune® HPVPDS0101 and PDS01ADC may not be effective, may be only only moderately effective or may prove to have undesirable or unintended side effects, toxicities or other characteristics that may preclude it from obtaining marketing approval or prevent or limit commercial use.

The process of obtaining marketing approvals, both in the United States and elsewhere, is expensive, may take many years and can vary substantially based upon a variety of factors. We cannot assure you that we will ever obtain any marketing approvals in any jurisdiction. Changes in marketing approval policies during the development period, changes in or the enactment of additional statutes or regulations or changes in regulatory review for each submitted product application may cause delays in the approval or rejection of an application. The FDA and comparable authorities in other countries have substantial discretion in the approval process and may refuse to accept any application or may decide that our data is insufficient for approval and require additional preclinical or other studies, and clinical trials. In addition, varying interpretations of the data obtained from preclinical testing and clinical trials could delay, limit or prevent marketing approval of Versamune® HPVPDS0101 and PDS01ADC. Additionally, any marketing approval we ultimately obtain may be limited or subject to restrictions or post-approval commitments that render the approved product not commercially viable.

There is no guarantee that any such CROs, clinical trial investigators or other third parties on which we rely will devote adequate time and resources to our development activities or perform as contractually required or in accordance with applicable laws and regulations. If any of these third parties fail to meet expected deadlines, adhere to our clinical protocols or meet regulatory requirements, otherwise perform in a substandard manner, or terminate their engagements with us, the timelines for our development programs may be extended or delayed or our development activities may be suspended or terminated. If any of our clinical trial sites terminate for any reason, we may experience the loss of follow-up information on subjects enrolled in such clinical trial unless we are able to transfer those subjects to another qualified clinical trial site, which may be difficult or impossible. In addition, certain of our scientific advisors or consultants who receive compensation from us are clinical trial investigators for our clinical trial. Although we believe our existing relationships are within the FDA’s guidelines, guidelines, if these relationships and any related compensation result in perceived or actual conflicts of interest, or the FDA concludes that the financial relationship may have affected the interpretation of the trial, the integrity of the data generated generated at the applicable clinical trial site may be questioned and the utility of the clinical trial itself may be jeopardized, which could result in the delay or rejection of any marketing application we submit by the FDA. Any such delay or rejection rejection could prevent us from commercializing Versamune® HPV,PDS0101, PDS01ADC or any other product candidates.

Even if we obtain FDA approval in the United States, we may never obtain approval for or commercialize Versamune® HPVPDS0101 or PDS01ADC in any other jurisdiction, which would limit our ability to realize each product’s full market potential.

In order to market Versamune® HPVPDS0101 or PDS01ADC in a particular jurisdiction, we must establish and comply with numerous and varying regulatory requirements on a country-by-country basis regarding safety and efficacy. Approval by the FDA in the United States does not ensure approval by regulatory authorities in other countries or jurisdictions.

In addition, clinical trials conducted in one country may not be accepted by regulatory authorities in other countries, and regulatory approval in one country does not guarantee regulatory approval in any other country. Approval processes vary among countries and can involve additional testing and validation and additional administrative review periods. Seeking foreign regulatory approval could result in difficulties and costs for us and require additional preclinical studies or clinical trials that could be costly and time consuming. Regulatory requirements can vary widely from country to country and could delay or prevent the introduction of Versamune® HPVPDS0101 or PDS01ADC in those countries. Versamune® HPVPDS0101 or PDS01ADC is not approved for sale in any jurisdiction, including in international markets, and we do not have experience in obtaining regulatory approval in international markets. If we fail to comply with regulatory requirements in international markets or to obtain and maintain required approvals, or if regulatory approvals in international markets are delayed, our target market will be reduced.

From time to time, we may publicly disclose interim, topline or preliminary data from our sponsored or investigator initiated clinical trials, such as preliminary topline results which are based on a preliminary analysis of then-available data, and the results and related findings and conclusions are subject to change following a full analysis of all data related to the particular trial. We also make assumptions, estimations, calculations and conclusions as part of our analyses of data, and in doing so we may not have received or had the opportunity to fully and carefully evaluate all data. In addition, we may report preliminary analyses of only certain endpoints rather than all endpoints. As a result, the interim, topline or preliminary results that we report may differ from future results of the same trials, or different conclusions or considerations may qualify such results, once additional data has been received and fully evaluated. Topline data also remainremains 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, interim, topline and preliminary data should be viewed with caution until the final data are available. We may also disclose interim data from our clinical trials. Interim data from clinical trials that we may complete are subject to the risk that one or more of the clinical outcomes may materially change as subject enrollment continues and more subject data becomes available. Adverse differences between interim, topline or preliminary data and final data could significantly harm our reputation and business prospects. Further, disclosure of interim, topline or preliminary data by us or by our competitors could result in volatility in the price of our common stock.

In addition, the design of a clinical trial can effectaffect whether its results will support approval of a drug and flaws in the design of a clinical trial may not become apparent until the clinical trial is well advanced. We have limited experience in designing clinical trials and may be unable to design and conduct a clinical trial to support marketing approval. Further, if our product candidates are found to lack safety or efficacy, we will not be able to obtain marketing approval for them and our business would be harmed. A number of companies in the pharmaceutical industry, including those with greater resources and experience than us, have suffered significant setbacks in advanced clinical trials, even after obtaining promising results in preclinical studies and earlier clinical trials.

Even if we obtain regulatory approval, we will still face extensive ongoing regulatory requirements, and Versamune® HPV,PDS0101, PDS01ADC and other candidates may face future development and regulatory difficulties.

Marketing of Versamune® HPVPDS0101 alone or in combination with PDS01ADC, if approved, along with the manufacturing processes, post- approval clinical data, labeling, packaging, distribution, adverse event reporting, storage, recordkeeping, export, import, advertising and promotional activities for Versamune® HPV,PDS0101, among other things, will be subject to extensive and ongoing requirements of and review by the FDA and other regulatory authorities. These requirements include submissions of safety, efficacy and other post-marketing information and reports, establishment of registration and drug listing requirements, continued compliance with current Good Manufacturing Practice, or cGMP, requirements relating to manufacturing, quality control, quality assurance and corresponding maintenance of records and documents, requirements regarding the distribution of samples to physicians and recordkeeping and current Good Clinical Practice, or cGCP requirements for any clinical trials that we conduct post-approval. Even if marketing approval of Versamune® HPVPDS0101 or PDS01ADC is granted, the approval may be subject to limitations on the indicated indicated uses for which Versamune® HPVPDS0101 may be marketed or to the conditions of approval. If Versamune® HPVPDS0101 or PDS01ADC receives marketing approval, an accompanying label may limit the approved use of the product(s), which could limit sales.

We may agree to or the FDA may impose requirements for costly post-marketing studies or clinical trials and surveillance to monitor the safety and/or efficacy of Versamune®PDS0101 HPV and PDS01ADC. The FDA closely regulates the post-approval marketing and promotion of drugs to ensure drugs are marketed only for the approved indications and in accordance with the provisions of the approved labeling. The FDA imposes stringent restrictions on manufacturers’ communications regarding off-label use and if we promote or otherwise market Versamune® HPVPDS0101 or PDS01ADC for indications other than those for which it is approved, we may be subject to certain enforcement actions. Violations of the Federal Food, Drug, and Cosmetic Act relating to the promotion of prescription biopharmaceutical products may lead to FDA enforcement actions and investigations alleging violations of federal and state health care fraud and abuse laws, as well as state consumer protection laws.

In addition, later discovery of previously unknown adverse events or other problems with Versamune® HPV,PDS0101, manufacturers or manufacturing processes, or failure to comply with regulatory requirements, may yield various results, including:

Even if Versamune® HPVPDS0101 or PDS01ADC receives licensure, it may fail to achieve market acceptance by physicians, patients, third-party payors or others in the medical community necessary for commercial success.

If Versamune® HPVPDS0101 alone or in combination with PDS01ADC receives marketing approval, it may nonetheless fail to gain sufficient market acceptance by physicians, patients, third-party payors and others in the medical community. If Versamune® HPVPDS0101 or PDS01ADC does not achieve an adequate level of acceptance, we may not generate significant revenues and become profitable. The degree of market acceptance, if approved for commercial sale, will depend on a number of factors, including but not limited to:

We are a clinical-stage immunotherapy company developing a growing pipeline of targeted cancer immunotherapies based on our Versamune®, Versamune® in combination with our IL-12 fused anti-body drug conjugate (ADC) PDS01ADC (formerly known as PDS0301/M9241/NHS-IL-12).PDS01ADC. In addition, we are developing the Infectimune® T cell-activator in infectious diseases. We believe our targeted immunotherapies have the potential to overcome the limitations of current immunotherapy approaches through the activation of the right type, quantity and potency of T cells. Versamune®, and Versamune® in combination with PDS01ADC are utilized for treatments in oncology and Infectimune®, for treatments in infectious disease. When paired with an antigen, which is a disease-related protein that is recognizable by the immune system, Versamune® and Infectimune® have both been shown to induce, in vivo, in-vivo, large quantities of high-quality, highly potent polyfunctional CD4 helper and CD8 killer T cells, a specific sub-type of T cell that is more effective at killing infected or target cells. Infectimune® is also designed to promote the induction of disease-specific neutralizing antibodies. PDS01ADC is an investigational tumor targeting IL-12 that we believe may enhance the proliferation, potency and longevity of T cells in the tumor microenvironment. Based on preclinical studies and recent investigational clinical data, we believe that Versamune® in combination with PDS01ADC may enhance the proliferation, potency and longevity of antigen specific multifunctional CD8 T cells in the tumor microenvironment and work synergistically to overcome tumor immune suppression.

In May 2024, at a virtual key opinion leader event, updated interim data was presented based on a November 30, 2023 cut-off from our VERSATILE-002 Phase 2 clinical trial evaluating the combination of Versamune®PDS0101 HPV in combination with Merck’s anti-PD-1 therapy, Keytruda® (pembrolizumab) which is an FDA-approved standard of care for first-line treatment of recurrent/metastatic head and neck cancer. Data from 53 patients was presented.

In August 2024, we provided an update to our clinical strategy following discussions with the FDA. During the August 2024 update, we announced our intent to initiate a registrational trial in first line treatment in HPV16-positive recurrent/metastatic HNSCC with the double combination of Versamune® HPVPDS0101 + pembrolizumab.

In October 2024, we announced updated data from the IMMUNOCERV Phase 2 clinical trial evaluating Versamune® HPVPDS0101 with chemoradiation to treat locally advanced cervical cancer presented at the American Society for Radiation Oncology (ASTRO) Annual Meeting 2024.

In NovemberMarch 2020,2025, we initiated our VERSATILE-002VERSATILE-003 Phase 23 clinical trial evaluating the combination of Versamune® HPVPDS0101 in combination with Merck’s the anti-PD-1 therapy,therapy Keytruda®pembrolizumab (versus pembrolizumab) whichas isa the FDA-approved standard of care for first-line treatment of recurrent/ metastatic head and neck cancer commenced. Enrollment in stage 2 of 2 for the ICI-naïve arm and the ICI-resistant arms are complete.monotherapy. The clinical trial will evaluate the efficacy and safety of this therapeutic combination as a first and second line treatment in patients with recurrent or metastatic head and neck cancer and high-risk human papillomavirus-16 (HPV16) infection.

In this trialtrial, sponsored by us, patients whose cancer has returned following initial treatment or spread (metastasized) will be treated with witheither the combination of Versamune®PDS0101and HPVpembrolizumab andor Keytruda® with pembrolizumab alone, to evaluate if the addition of Versamune® HPVPDS0101 might improve the efficacy reported in published studies of Keytruda®pembrolizumab alone. Patients in the trial will receive a total of 5 cycles of combination therapy in the context of standard of care Keytruda®pembrolizumab therapy administered every three weeks until disease progression. The primary endpoint of VERSATILE-002 is themedian objectiveoverall response rate,survival, or ORR,mOS, at six months following initiation of treatment. Following Therediscussions arewith twothe cohortsFDA in December 2025, we amended the trial’s protocol, among other modifications, to include progression-free survival (PFS) as an interim primary endpoint of the trial. CohortPatients 1already isenrolled for patients who have yetprior to bethe treatedamendment remain withon anthe immune checkpoint inhibitor (ICI naïve)trial and cohortcontinue 2to whichreceive consists of patients who have failed immune checkpoint inhibitor therapy (ICI resistant).treatment.

In June 2023, an abstract was presented at the 2023 American Society of Clinical Oncology: Abstract number 6012, Safety and Efficacy of Immune Checkpoint Inhibitor (ICI) Naïve Cohort from Study of Versamune® HPVPDS0101 and Pembrolizumab in HPV16-positive Head and Neck Squamous Cell Carcinoma (HNSCC). The abstract was also selected as one of the featured posters to be reviewed by an expert panel in the Head and Neck Cancer discussion session. Data on 34 patients was presented. The data from the abstract is as follows:

In October 2023, at a key opinion roundtable updated interim data was presented based on an August 2, 2023 cut-off from our VERSATILE-002 Phase 2 clinical trial evaluating the combination of Versamune® HPVPDS0101 in combination with Merck’s anti-PD-1 therapy, Keytruda® (pembrolizumab) which is an FDA-approved standard of care for first-line treatment of recurrent/ metastatic head and neck cancer. Data on 52 patients was presented. The data from the roundtable based on investigator assessment was as follows:

In May 2024, at a virtual key opinion leader event, updated interim data was presented based on a November 30, 2023 cut-off from our VERSATILE-002 Phase 2 clinical trial evaluating the combination of Versamune® HPVPDS0101 in combination with Merck’s anti-PD-1 therapy, Keytruda® (pembrolizumab) which is an FDA-approved standard of care for first-line treatment of recurrent/metastatic head and neck cancer. Data from 53 patients was presented. The data from the event based on investigator assessment was as follows:

In August 2024, we provided an update to our clinical strategy following discussions with the FDA. During the August 2024 update, we announced our intent to initiate a registrational trial in first line treatment in HPV16-positive recurrent/metastatic HNSCC with the double combination of Versamune® HPVPDS0101 + pembrolizumab.

MD Anderson Cancer Center (IMMUNOCERV): Versamune® HPVPDS0101 + Chemoradiotherapy

In October 2020, a Versamune® HPV Phase 2 IIT was initiated with The University of Texas MD Anderson Cancer Center and is actively recruiting patients. This clinical trial is investigatinginvestigated the safety and anti-tumor efficacy of Versamune® HPVPDS0101 in combination with standard-of-care chemo-radiotherapy, or CRT, and their correlation with critical immunological biomarkers in patients with locally advanced cervical cancer. We believe that Versamune® has strong T cell induction with the potential to enhance efficacy of the current standard of care CRT treatment in this indication with the FDA at this meeting.

In October 2023, data demonstrating Versamune® HPVPDS0101 in combination with standard-of-care (SOC) chemoradiotherapy was associated with a rapid decline in human papillomavirus circulating cell-free DNA (ctHPV-DNA), a potential predictive biomarker of treatment response. The data from the IMMUNOCERV Phase 2 clinical trial was featured in an oral presentation at the American Society for Radiation Oncology Annual Meeting which included the following:

In October 2024, we announced updated data from the IMMUNOCERV Phase 2 clinical trial evaluating Versamune® HPVPDS0101 with chemoradiation to treat locally advanced cervical cancer presented at the American Society for Radiation Oncology (ASTRO) Annual Meeting 2024 which included the following:

Mayo Clinic: Versamune® HPVPDS0101 Monotherapy and in combination with Keytruda®pembrolizumab

In February 2022, we initiated an Investigator-Initiated Trial (ITT), MC200710, for Versamune® HPVPDS0101 alone or in combination with the immune checkpoint inhibitor, Keytruda®,pembrolizumab, in patients with HPV-positive oropharyngeal cancer (HPV(+)OPSCC) at high risk of recurrence. The trial is being led by Drs. David Routman, Katharine Price, Kathryn Van Abel, and Ashish Chintakuntlawar at Mayo Clinic, a nationally and internationally recognized center of excellence for the treatment of head and neck cancers. We believe that this trial not only broadens our addressable patient population of those affected by the increasing incidence of HPV(+)OPSCC, but also allows us to better understand the activity of Versamune® HPVPDS0101 alone or in combination with Keytruda® in earlier stages of disease. This trial is currently open for enrollment.

In this trial, treatment will be administered before patients proceed to transoral robotic surgery (TORS) with curative intent. Treatment in this setting is referred to as neoadjuvant treatment. Versamune® HPVPDS0101 has been shown to induce killer T cells that target and kill HPV-positive cancers, either alone or in combination with ICIs in preclinical studies, and in combination in clinical studies of patients with advanced recurrent/metastatic HPV-positive cancers. This trial will explore whether Versamune® HPVPDS0101 with or without checkpoint inhibition may increase HPV-specific anti-tumor responses, potentially resulting in tumor shrinkage, pathologic regression, and decreases in circulating tumor DNA (ctDNA).

In April 2020, the above-mentioned CRADA between PDS Biotech and the NCI was expanded beyond Versamune® HPVPDS0101 to include clinical and preclinical development of PDS0103. PDS0103 is an investigational immune therapy owned by us and designed to treat cancers associated with the mucin-1, or MUC1, oncogenic protein. These include cancers such as ovarian, breast, colorectal and lung cancers. PDS0103 combines Versamune® with novel highly immunogenic agonist epitopes of MUC1 developed by the NCI and licensed by us.

MUC1 is highly expressed in several types of cancer and has been shown to be associated with drug resistance and poor disease prognosis in breast, colorectal, lung and ovarian cancers, for which PDS0103 is being developed. Expression of MUC1 is often associated with poor disease prognosis, due in part to drug resistance. In preclinical studies, and similarly to Versamune® HPV,PDS0101, PDS0103 demonstrated the ability to generate powerful MUC1-specific CD8 killer T cells.

PDS01ADC (formerly known as PDS0301/M9241/NHS-IL-12) is a novel investigational IL-12 fused antibody drug conjugate (IgG1), tumor-targeting interleukin 12 (IL-12) immune-cytokine immune-cytokine that enhances the proliferation, potency and longevity of T cells in the tumor microenvironment. Together with Versamune® based immunotherapies PDS01ADC works synergistically to overcome tumor immune suppression and to promote a targeted T cell attack against cancers. As with Versamune®, PDS01ADC is given by a simple subcutaneous injection. Clinical data suggests the addition of PDS01ADC to Versamune® based immunotherapies may demonstrate significant disease control in advanced cancer patients by shrinking tumors and/or prolonging life.

With the exclusive global license agreement with Merck KGaA, Darmstadt, Germany for PDS01ADC, we believe we have simplified our registrational pathway for the NCI-led triple combination by owning both Versamune® HPVPDS0101 and PDS01ADC and combining these agents with an FDA approved ICI. PDS01ADC has been designed to overcome the limitations of cytokine therapy as explained above, and based on extensive preclinical studies performed at the NCI evaluating PDS01ADC as a monotherapy and also in combinations with established standard of care treatments for cancer, we believe that PDS01ADC has significant potential as a cytokine therapy independent of Versamune®. Based on the informative preclinical studies, a number of ITT Phase 2 trials are currently in progress at the NCI, some of which are outlined below:

Based on the preclinical data with the universal seasonal flu vaccine and the current focus of the NIAID in developing more effective flu vaccines, we have decided to focus our near-term infectious disease activities to align with the interests of the NIAID Collaborative Influenza Vaccine Innovation Centers (CIVICs) program. This maywill involve development of a universal seasonal flu vaccine and the potential development of a universal pandemic influenza vaccine based on similar computationally designed antigens as have shown promise with Infectimune®.

ThereWith the exception of the risk factors noted below, there have been no material changes from our risk factors as previously reported in our Annual Report on Form 10-K for the year ended December 31, 2025. However, any investment in our business involves a high degree of risk. Before making an investment decision, you should carefully consider the information we include in this Quarterly Report on Form 10-Q, including our unaudited interim Condensed Consolidated Financial Statements and accompanying notes, our Annual Report on Form 10-K for the year ended December 31, 2025 filed on March 30, 2026, including the risk factors and our financial statements and related notes contained therein, and the additional information in the other reports we file with the Securities and Exchange Commission, including, without limitation, the risk factors previously disclosed in our prior quarterly reports on Form 10-Q filed during this fiscal year. These risks may result in material harm to our business and our financial condition and results of operations. In this event, the market price of our common stock may decline and you could lose part or all of your investment. Additional risks that we currently believe are immaterial may also impair our business operations. Our business, financial conditions and future prospects and the trading price of our common stock could be harmed as a result of any of these risks.

We believe our investigational targeted immunotherapies have the potential to overcome the limitations of current immunotherapy approaches through the activation of the right type, quantity and potency of T cells. PDS0301, Versamune®, and Versamune® in combination with PDS01ADCPDS0301 are being developed for treatments in oncology and Infectimune® is being developed for treatments in infectious disease. When paired with an antigen, which is a disease-related protein that is recognizable by the immune system, Versamune® and Infectimune® have both been shown to induce, in-vivo, large quantities of high-quality, highly potent polyfunctional CD4 helper and CD8 killer T cells, a specific sub-type of T cell that is more effective at killing infected or target cells. Infectimune® is also designed to promote the induction of disease-specific neutralizing antibodies. PDS01ADCPDS0301 is an investigational tumor targeting IL-12 that we believe may enhance the proliferation, potency and longevity of T cells in the tumor microenvironment. Based on preclinical studies and recent investigational clinical data, we believe that Versamune® in combination with PDS01ADC may enhance the proliferation, potency and longevity of antigen specific multifunctional CD8 T cells in the tumor microenvironment and work synergistically to overcome tumor immune suppression.

In July 2025, we announced that the colorectal cancer cohort of a Phase 2 clinical trial with PDS01ADCPDS0301 in combination with Hepatic Artery Infusion Pump (HAIP) and systemic therapy met the pre-defined criteria for expansion to stage 2 following positive stage 1 results.

In March 2025, we initiated our VERSATILE-003 Phase 3 clinical trial evaluating the combination of PDS0101 in combination with the anti-PD-1 therapy pembrolizumab versus pembrolizumab as a monotherapy. The clinical trial willwas designed to evaluate the efficacy and safety of this therapeutic combination as a first line treatment in patients with recurrent or metastatic head and neck cancer and high-risk human papillomavirus-16 (HPV16) infection.

In this trial, sponsored by us, patients whose cancer has returned following initial treatment or spread (metastasized) will bewere treated with either the combination of PDS0101and pembrolizumab or with pembrolizumab alone, to evaluate if the addition of PDS0101 might improve the efficacy of pembrolizumab alone. Patients in the trial will receivereceived a total of 5 cycles of combination therapy in the context of standard of care pembrolizumab therapy administered every three weeks until disease progression. The primary endpoint of VERSATILE-003 iswas median overall survival, or mOS, at six months following initiation of treatment. Following discussions with the FDA in December 2025, we amended the trial’s protocol, among other modifications, to include progression-free survival (PFS) as an interim primary endpoint of the trial. Patients already enrolled prior to the amendment remain on the trial and continue to receive treatment.

In this trial sponsored by us, patients whose cancer had returned following initial treatment or spread were treated with the combination of PDS0101 and Keytruda® to evaluate if the addition of PDS0101 might improve the efficacy reported in published studies of Keytruda® alone. Patients in the trial received a total of 5 cycles of combination therapy in the context of standard of care Keytruda® therapy administered every three weeks until disease progression. The primary endpoint of VERSATILE-002 iswas the objective response rate, or ORR, at six months following initiation of treatment. There arewere two cohorts in the trial. Cohort 1 iswas for patients who have yet to be treated with an immune checkpoint inhibitor (ICI naïve) and cohort 2 which consistsconsisted of patients who havehad failed immune checkpoint inhibitor therapy (ICI resistant).

In August 2025, we announced final topline survival data from our VERSATILE-002 Phase 2 trial in head and neck cancer. 53 patients were enrolled in the 1L R/M HNSCC arm of the trial:

In October 2020, a Phase 2 IIT was initiated with The University of Texas MD Anderson Cancer Center and is actively recruiting patients.Center. This clinical trial investigated the safety and anti-tumor efficacy of PDS0101 in combination with standard-of-care chemo-radiotherapy, or CRT, and their correlation with critical immunological biomarkers in patients with locally advanced cervical cancer. We believe that Versamune® has strong T cell induction with the potential to enhance efficacy of the current standard of care CRT treatment in this indication with the FDA at this meeting.indication.

In February 2022, we initiated an Investigator-Initiated Trial (ITT), MC200710, for PDS0101 alone or in combination with the immune checkpoint inhibitor, pembrolizumab, in patients with HPV-positive oropharyngeal cancer (HPV(+)OPSCC) at high risk of recurrence. The trial is beingwas led by Drs. David Routman, Katharine Price, Kathryn Van Abel, and Ashish Chintakuntlawar at Mayo Clinic, a nationally and internationally recognized center of excellence for the treatment of head and neck cancers. We believe that this trial not only broadens our addressable patient population of those affected by the increasing incidence of HPV(+)OPSCC, but also allows us to better understand the activity of PDS0101 alone or in combination with Keytruda® in earlier stages of disease. This trial is currently open for enrollment.

In this trial, treatment will bewas administered before patients proceed to transoral robotic surgery (TORS) with curative intent. Treatment in this setting is referred to as neoadjuvant treatment. PDS0101 has been shown to induce killer T cells that target and kill HPV-positive cancers, either alone or in combination with ICIs in preclinical studies, and in combination in clinical studies of patients with advanced recurrent/metastatic HPV-positive cancers. This trial will explore explored whether PDS0101 with or without checkpoint inhibition may increase HPV-specific anti-tumor responses, potentially resulting in tumor shrinkage, pathologic regression, and decreases in circulating tumor DNA (ctDNA).

National Cancer Institute: PDS0101 + PDS01ADCPDS0301 + Bintrafusp Alfa

In January 2025, we submitted an investigational new drug application to the FDA for a Phase 1 trial with PDS0103PDS0301 and PDS01ADCPDS0103 in colorectal cancer. At the time of this Quarterly Report, we have not initiated this trial.

Our current clinical pipeline of Versamune®PDS0301 and PDS01ADCVersamune® based therapies is as follows:

We believe that the key differentiating attributes of the Infectimune® platform technology are strong induction of CD8 and CD4 T cells as well as antibodies which can be leveraged to improve treatment and preventive options in several infectious disease indications. In January 2022, we presented preclinical data on our universal flu program sponsored by the National Institute of Allergy and Infectious Disease (NIAID) demonstrating the potential of the Infectimune® technology with computationally designed influenza proteins developed by the laboratory of Dr. Ted Ross at the University of Georgia to generate broadly protective anti-influenza immune responses across multiple strains of influenza. This data has provided a unique opportunity to highlight Infectimune®’sthe potentially transformative utility utilityof Infectimune® in the development of more broadly effective and longer lasting protective vaccines. Current preventive and prophylactic vaccine approaches and technologies predominantly focus on creating strong induction of antibody responses. However, the induction of T cell responses, in addition to antibody responses, provides more durable and broad protection against infectious diseases.

Since our inception we have devoted substantially all our resources to developing our Versamune® and Infectimune® platforms, and products derived thereof, as well as PDS01ADC. PDS0301. This includes advancing preclinical programs, conducting clinical trials, manufacturing PDS0101 and PDS01ADCPDS0301 for clinical trials, and providing general and administrative support. We have funded our operations primarily from the issuance of common stock and issuance of debt. We have not generated any product revenue to date.

We have never been profitable and have incurred net losses in each year since inception. Our net losses were $7.3$17.1 million, and $8.5 $17.9 million for the threesix months ended March 31,June 30, 2026 and 2025, respectively. As of MarchJune 31,30, 2026, we had an accumulated deficit of $224.0$233.7 million. Substantially all of our net losses have resulted from costs incurred in connection with our research and development programs and from general and administrative costs associated with these operations.

As of MarchJune 31,30, 2026, we had $21.7$5.6 million in cash and cash equivalents.

We expect that our research and development expenses will increase significantly over the next several years as we advance our Versamune® and PDS01ADC clinical andPDS0301 product candidates candidate into and through clinical trials, pursue regulatory approval of our Versamune® and PDS01ADCPDS0301 product candidates and prepare for a possible commercial launch, all of which will also require a significant investment in contract research services, manufacturing process validation and inventory related costs.

TheComparison following table summarizesof the results of our operations for the threeThree months endedJune March 31,30, 2026 and 2025:

Research and development (R&D) expenses decreased to $3.5$3.3 million for the three months ended MarchJune 31,30, 2026 from $5.8$4.2 million for the three months ended MarchJune 31,30, 2025. The decrease of $2.3$0.9 million was primarily attributable to a decrease of $1.2$1.0 million in clinical trial costs, a decrease of $0.7$0.4 million in manufacturing costs, and a decrease of $0.4$0.2 million in personnel costs.costs, partially offset by an increase of $0.7 million in stock-based compensation expense.

General and administrative expenses decreased to $3.1$3.2 million for the three months ended MarchJune 31,30, 2026 from $3.3$3.4 million for the three months ended MarchJune 31,30, 2025. The decrease of $0.2 million was primarily attributable to a decrease in professional fees.

Income tax benefit was $0zero for the threesix months ended MarchJune 31,30, 2026 and $1.2 million for the threesix months ended MarchJune 31,30, 2025. The decrease of $1.2 million was due to us having met the statutory $20 million lifetime cap on total cumulative value of NOLs sold, which makes us ineligible to participatecontinue participation in the New Jersey Technology Business Tax Certificate Transfer Net Operating Loss (NOL) program.

In August 2024, we entered into an Amended and Restated At Market Issuance Sales Agreement, or the New Sales Agreement, with B. Riley Riley Securities, Inc. and H.C. Wainwright & Co., LLC, with terms that are substantially consistent with those included in the original Sales Agreement. During the three and six months ended MarchJune 31,30, 20262026, we sold 0 shares and 2025, the Company sold 937,420 shares ofshares, common stock and 205,250 sharesrespectively, of common stock forwith a net value of $0.85$0 million and $0.3$0.8 million, respectively, pursuant to the New Sales Agreement. During the three and six months ended June 30, 2025, we sold 960,511 and 1,165,861 shares, respectively, of common stock with a net value of $1.5 and $1.8 million, respectively, pursuant to the New Sales Agreement. The New Sales Agreement was terminated on May 1, 2026.

As of MarchJune 31,30, 2026, we had $21.7$5.6 million in cash and cash equivalents. Our primary uses of cash are to fund operating expenses, primarily research and development expenditures. Cash used to fund operating expenses is impacted by the timing of when we pay these expenses, as reflected in the change in our outstanding accounts payable and accrued expenses.

We plan to continue to fund our operations and capital funding needs through existing cash and additional equity and/or debt financing. However, we cannot be certain that additional financing will be available when needed or that, if available, financing will be obtained on terms favorable to us or our existing stockholders. We may also enter into government funding programs and consider selectively partnering for clinical development and commercialization. The sale of additional equity would result in additional dilution to our stockholders. Incurring debt financing would result in debt service obligations, and the instruments governing such debt could provide for operating and financing covenants that would restrict our operations. If we are unable to raise additional capital in sufficient amounts or on acceptable terms, we may be required to delay, limit, reduce, or terminate our product development or future commercialization efforts or grant rights to develop and market immunotherapies that we would otherwise prefer to develop and market ourselves. In addition, the Debentures require us to maintain minimum cash balances in a deposit account subject to an account control agreement and impose restrictive covenants, as described above. Any of these actions could harm our business, results of operations and prospects.

Net cash used in operating activities was $4.3$7.2 million and $9.0 $18.1 million for the threesix months ended MarchJune 31,30, 2026 and 2025, respectively. The decrease in net cash used in operating activities of $4.7$10.9 million was primarily due to a decreasenet in the non-cash stock-based compensation expenseincrease of $0.1$2.0 million and a decrease in issuance of shares in consulting agreements of $0.2 million, offset by a decrease in net loss of $1.1 million, an increase in the amortization of debt discount and loss on retirement of $0.2debt, millionan increase in stock-based compensation expense of $0.6 million, and changes in the timing of working capitalcapital. requirements,These includingchanges anwere increase in prepaid expenses and other assets,partially offset by decreasesa decrease in accrued expensesnet loss of $0.8 million and accountsa payable.decrease in the issuance of shares in consulting agreement of $0.2 million.

Net Cash ProvidedUsed byin Financing Activities

Net cash used in financing activities was $13.9 million for the six months ended June 30, 2026, compared to net cash provided by financing activities activitiesof $8.3 million for the threesix months ended MarchJune 31,30, 20262025. andThe 2025 decreased by $8.0$22.2 million change was primarily due to a $7.0 million decrease in proceeds from the issuance of common stock,stock of $7.0 million, a decrease in proceeds from the issuance of warrants and pre-funded warrants of $3.2 $2.1 million, and a decrease in proceeds from the issuance of debt of $14.9 million, partially offset by a decrease ofin $1.6loan millionprincipal inpayments and loan repayments andof $0.5$2.6 million and a decrease in net proceeds from the issuance of common stock throughunder ourthe at-the-market program.offering program of $0.8 million.

We evaluated whether there are any conditions and events, considered in the aggregate, that raise substantial doubt about our ability to continue as a going concern within one year after the filing of this Quarterly Report. Our budgeted cash requirements in 2026 and beyond include expenses related to continuing development and clinical studies as well as payments on our debt. Until we can generate significant cash from our operations, we expect to continue to fund our operations with available financial resources. These financial resources may not be adequate to sustain our operations. While we intend to finance our cash needs principally through equity or debt financings, collaborations, strategic alliances, or license agreements with third parties, there is no assurance that new financing will be available to us on commercially acceptable terms or in the amounts required, if at all. In addition, the terms of the Debentures allow for the holders to call the outstanding balance of the Debentures if we fail to maintain the minimum cash balances required by the Debentures.

There have been no material changes to our critical accounting policies and estimates during the threesix months ended MarchJune 31,30, 2026 from those disclosed in our Annual Report on Form 10-K for the year ended December 31, 2025.