GeoVax to Showcase Positive Immune Response Data for GEO-CM04S1 in CLL Patients at EHA 2025 Congress
GeoVax Labs, Inc. will present clinical data at the European Hematology Association 2025 Congress, demonstrating the superior cellular immune response of its GEO-CM04S1 vaccine in chronic lymphocytic leukemia patients compared to mRNA-based vaccines.

GeoVax Labs, Inc., a clinical-stage biotechnology company, is set to present promising clinical data for its next-generation COVID-19 vaccine candidate, GEO-CM04S1, at the European Hematology Association (EHA) 2025 Hybrid Congress. The data highlights the vaccine's superior cellular immune response in chronic lymphocytic leukemia (CLL) patients, a group known for their suboptimal protective responses to COVID-19 and other vaccines due to immune dysfunction.
The presentation, titled 'MVA-Based GEO-CM04S1 Vaccine Results in Improved Cellular Immune Response in Patients with Chronic Lymphocytic Leukemia (CLL) Compared with mRNA-Based Vaccine: Initial Results of a Phase II Randomized Study', will be delivered by Dr. Alexey V. Danilov from the City of Hope Comprehensive Cancer Center. This study underscores the potential of GeoVax's MVA multi-antigen platform to address the needs of immunocompromised individuals, offering a glimpse into the future of vaccine development for vulnerable populations.
GEO-CM04S1, designed using a synthetic Modified Vaccinia Ankara (MVA) vector platform, expresses both spike (S) and nucleocapsid (N) antigens of SARS-CoV-2. This approach aims to provide broader and more durable immune protection, a critical advancement for populations with compromised immune systems. The Phase II clinical trial results to be presented at EHA 2025 could mark a significant step forward in the fight against COVID-19, especially for those who have not benefited fully from existing vaccines.
The implications of this research are vast, not only for CLL patients but also for the broader field of immunology and vaccine development. By demonstrating the efficacy of GEO-CM04S1 in a challenging patient population, GeoVax is paving the way for more inclusive and effective vaccine strategies. This development is particularly timely as the world continues to grapple with the evolving challenges posed by COVID-19 and its variants.