Business Description

Overview We are a commercial-stage biopharmaceutical company specializing in the advancement of innovative precision medicines to improve the lives of patients. We are leveraging our proprietary technology platforms to develop product candidates designed to target urgent and intractable diseases in our core therapeutic areas of immuno-oncology, autoimmune disorders, and infectious diseases. We believe that our array of technology platforms uniquely positions us among other biotechnology companies to advance precision medicine. Precision medicine is the practice of therapeutic product development that takes into account specific genetic variations within populations impacted by a disease to design targeted therapies to improve outcomes for a disease or patient population. Our proprietary and complementary technology platforms provide a strong foundation to realize the core promise of precision medicine by supporting our efforts to construct powerful gene programs to drive efficacy, deliver these programs through viral, non-viral, and microbe-based approaches to drive lower costs, and control gene expression to drive safety. Our therapeutic platforms, including AdenoVerse immunotherapy, and UltraCAR-T, are designed to allow us to precisely control the level and physiological location of gene expression and modify biological molecules to control the function and output of living cells to treat underlying disease conditions. We have developed a proprietary electroporation device, UltraPorator, designed to further streamline and ensure the rapid and cost-effective manufacturing of UltraCAR-T therapies. In August 2025, the FDA granted full approval to our product, Papzimeos (zopapogene imadenovec-drba, PRGN-2012), for the treatment of adults with recurrent respiratory papillomatosis (RRP). RRP is a rare, debilitating, and potentially life-threatening disease caused by chronic human papillomavirus (HPV) 6 or HPV 11 infection, which results in recurrent benign tumors in the respiratory tract. Papzimeos is a non-replicating adenoviral vector-based immunotherapy designed to express a fusion antigen comprising selected regions of HPV types 6 and 11 proteins. Papzimeos is designed to generate an immune response directed against HPV 6 and HPV 11 proteins in patients with RRP. Our clinical pipeline includes PRGN-2009, which is based on our AdenoVerse immunotherapy platform; and PRGN-3005, PRGN-3006 and PRGN-3007, which are built on our UltraCAR-T platform. We have completed enrollment in the Phase 1b clinical trial of PRGN-3006. As part of the strategic prioritization of our pipeline we announced in August 2024 that we have paused enrollment in the PRGN-3005 and PRGN-3007 clinical trials. In addition, we announced a plan to continue PRGN-2009 Phase 2 clinical trials under a cooperative research and development agreement ("CRADA") with the National Cancer Institute ("NCI") in recurrent/metastatic cervical cancer and in newly diagnosed HPV-associated oropharyngeal cancer. We exercise discipline in our portfolio management by systematically evaluating data from our preclinical programs in order to make rapid "go" and "no go" decisions. Through this process, we believe we can more effectively allocate resources to programs that we believe show the most promise and advance such programs to clinical trials. To guide our decision-making and operations, we have adopted the following tenets, which form the core of our operating ideology: • Financial Discipline . Responsibly allocate capital in an effort to ensure maximum value creation. • Active Portfolio Management . Continuously evaluate our portfolio and strictly adhere to data-driven "go" and "no go" decisions to advance programs with the highest probability of success. • Rapid Execution . Advance priority programs quickly to value inflection points. • Strategic Partnerships . Seek strategic partnerships to maximize value generation. Our Strategy Our strategy is to use our discovery and clinical development infrastructure to continue advancement of our clinical programs with the goal of improving outcomes for patients with significant unmet medical needs. The key elements of our strategy include: • Advancing our lead clinical stage programs and seeking opportunities to maximize their value. We are actively 9 Table of Contents advancing our lead programs that we believe have significant potential value.…