GeoVax Labs, Inc. presented positive interim Phase 2 clinical trial results for its COVID-19 vaccine candidate GEO-CM04S1 at the International Workshop on Chronic Lymphocytic Leukemia conference, showing superior performance compared to standard mRNA vaccines in immunocompromised patients. The data revealed that the proportion of chronic lymphocytic leukemia patients receiving GEO-CM04S1 achieved the study's primary immune endpoint, meeting statistical requirements to continue enrollment, while those in the mRNA vaccine arm did not.
Following interim analysis and the recommendation of the Data Safety Monitoring Board, further enrollment in the ongoing randomized Phase 2 trial (NCT05672355) is proceeding exclusively in the GEO-CM04S1 arm. Both vaccines demonstrated favorable safety profiles with no grade 3 or higher adverse events reported. The trial results highlight the significant unmet medical need among CLL patients, who represent a high-need population where first-generation COVID-19 vaccines often provide inadequate protection.
David Dodd, Chairman and CEO of GeoVax, stated that these data reinforce the value proposition of the company's multi-antigen MVA platform. Immunocompromised patients, including those with CLL, have not been adequately protected by current vaccines, and GEO-CM04S1 is demonstrating the ability to overcome this clinical gap. The vaccine represents both a clinical breakthrough and a compelling commercial opportunity in a multi-billion-dollar market segment.
GEO-CM04S1 is built on a Modified Vaccinia Ankara vector platform and differs from first-generation vaccines by encoding both the Spike and Nucleocapsid proteins of SARS-CoV-2 to drive broad, cross-variant, and durable immune protection. The vaccine's ability to induce nucleocapsid-specific responses sets it apart from existing single-antigen mRNA products. With millions of immunocompromised patients worldwide, including those with CLL and other hematologic malignancies, GEO-CM04S1 addresses a significant medical need where durable protection remains elusive. For more information about GeoVax's clinical programs, visit https://www.geovax.com.
The vaccine candidate is currently being evaluated in three Phase 2 clinical trials: as a primary vaccine for immunocompromised patients with blood cancers or post-transplant status, as a booster in CLL patients specifically, and as a more robust COVID-19 booster in previously mRNA-vaccinated healthy adults. The positive interim results position GeoVax to potentially lead in addressing the persistent challenge of COVID-19 protection in vulnerable patient populations who remain at high risk despite available vaccination options.
