Epeleuton

Dublin, Ireland, 19 April 2024: Afimmune announced today its collaborative partnership with Pathway to Cures (P2C) to support the development of Epeleuton as a potential therapeutic for Sickle Cell Disease (SCD). Afimmune is a clinical stage, private biotech, developing novel therapeutics for Sickle Cell Disease as well as other rare blood disorders. Pathway to Cures is the venture philanthropy fund of the American National Bleeding Disorders Foundation (NBDF) focused on investing in companies developing cures, therapies, or enabling technologies in support of the inheritable blood and bleeding disorders community. In addition to SCD, inheritable blood and bleeding disorders include rare and ultra-rare blood disorders, hemophilia A and B, von Willebrand disease, anemia, clotting disorders, and other hematological disorders, affecting more than 20 million people worldwide. “Afimmune welcomes the partnership with Pathway to Cures, an organization we are fully aligned with in our shared goal to support the development of new potential therapies for patients suffering from Sickle Cell Disease. We look forward to the results of our North American Phase 2 study in Sickle Cell Disease patients, expected early next year” said Dr. John Climax, Chairman and CEO of Afimmune. “Being able to support Afimmune in its clinical-stage research is a step in the right direction in addressing health equities, diversity, and inclusion in clinical research for inheritable blood and bleeding disorders,” said Ms. Teri Willey, Managing Director, and Officer for Pathway to Cures. “Afimmune’s unique scientific approach combined with NBDF’s focus on understanding the challenges specific to the community of patients living with an inheritable blood disorder is critical in addressing the health disparities through innovative treatments.” About Epeleuton Epeleuton is a 15-hydroxy eicosapentaenoic acid (15(S)-HEPE) ethyl ester, a novel synthetic fatty acid drug product. Epeleuton has been shown to have a unique dual mechanism of action for the treatment of SCD, targeting factors affecting severity, course of disease, and vaso-occlusive crisis risk. Afimmune is developing Epeleuton for SCD due to its novel disease-modifying preclinical efficacy, first-in-class opportunity, and a significantly reduced regulatory pathway. Epeleuton has received orphan drug designation for the treatment of SCD from the FDA. A phase 2 study of Epeleuton is currently being enrolled in sites across North America. For more information, please visit https://clinicaltrials.gov/study/NCT05861453. About Sickle Cell Disease SCD is a group of inherited, progressive blood disorders carried by the β allele of the hemoglobin gene with an expected 30-year reduced life expectancy. The disease is characterized by abnormal polymerization of hemoglobin during oxygenation which results in the sickling of red blood cells. The disease is rare, with an estimated prevalence of only ~100,000 people affected in the US and ~52,000 people in the EU. About Afimmune Afimmune, headquartered in Dublin, Ireland, is a clinical stage drug discovery and development company working on new medicines to improve the quality of life for people with rare and inflammatory diseases. For more information on Afimmune, visit www.afimmune.com. Contact investor.relations@afimmune.com About Pathway to Cures Pathway to Cures (P2C) is the venture philanthropy fund of the National Bleeding Disorders Foundation created to accelerate the development of cures across all inheritable blood and bleeding disorders. In collaboration with other organizations, P2C invests in innovative therapies and technologies, leveraging the deep resources and scientific community relationships of the National Bleeding Disorders Foundation. By reinvesting proceeds from investments back into the Fund, P2C will amplify the investment impact, support promising companies, and build a portfolio of investments that further the mission of the National Bleeding Disorders Foundation. For more information, visit www.pathwaytocures.org or contact Renee Peck at rpeck@pathwaytocures.org. About National Bleeding Disorders Foundation The National Bleeding Disorders Foundation is dedicated to finding better treatments and cures for inheritable blood and bleeding disorders and to preventing complications through research, education, and advocacy. For more information, visit hemophilia.org.

Dublin, Ireland, 8 November 2023: Afimmune, a clinical stage biopharmaceutical company developing novel rare disease therapeutics, today announced that recruitment has commenced in the first clinical trial evaluating Epeleuton in patients with sickle cell disease (SCD). The open-label trial design will be presented at the American Society of Hematology (ASH) Annual Meeting to be held in San Diego, California during December 9-12, 2023. Commenting on the study, Dr. Biree Andemariam, MD, Professor of Medicine and Director of the New England Sickle Cell Institute at UConn Health and study lead investigator said, “This study is an important milestone in the development of a novel therapeutic that may have the potential to address multiple aspects of sickle cell disease. The development and provision of safe and effective therapeutics is an important part of improving outcomes and quality of life for individuals living with sickle cell disease”. Epeleuton was recently granted Rare Pediatric Disease and Fast-Track designations by the FDA after opening its IND, in addition to orphan drug designations from the FDA and the EMA. “We are excited to share the progress of Epeleuton’s clinical development with the ASH community. We are working with urgency to bring forward this potential therapy to patients who need effective treatment options” said Dr. Moayed Hamza, Chief Medical Officer of Afimmune. The accepted abstract is available online on the ASH website: A PHASE 2, OPEN-LABEL STUDY TO ASSESS THE PHARMACOKINETICS,PHARMACODYNAMICS AND SAFETY OF ORALLY ADMINISTERED EPELEUTON IN PATIENTS WITH SICKLE CELL DISEASE Session: 114. Sickle Cell Disease Abstract number: 1159 About Epeleuton Epeleuton is 15-hydroxy eicosapentaenoic acid (15(S)-HEPE) ethyl ester, a novel synthetic fatty acid drug product. Epeleuton has been shown to have a unique dual mechanism of action for the treatment of SCD, targeting factors affecting severity, course of disease and vaso-occlusive crisis risk. Afimmune is developing Epeleuton for SCD due to its novel disease-modifying preclinical efficacy, first-in-class opportunity and a significantly reduced regulatory pathway. Epeleuton has received orphan drug designation for the treatment of SCD from the FDA and the EMA, in addition to rare pediatric disease and fast track designations from the FDA. About Sickle Cell Disease SCD is a group of inherited, progressive blood disorders carried by the β allele of the hemoglobin gene with an expected 30-year reduced life expectancy. The disease is characterized by abnormal polymerization of hemoglobin during oxygenation which results in the sickling of red blood cells. The disease is rare, with an estimated prevalence of only ~100,000 people affected in the US and ~52,000 people in the EU. About Afimmune Afimmune, headquartered in Dublin, Ireland, is a clinical stage drug discovery and development company working on new medicines to improve the quality of life for people with rare and inflammatory diseases. Contact investor.relations@afimmune.com