GeoVax Labs, Inc. (Nasdaq: GOVX) announced the publication of preclinical research on bioRxiv demonstrating that a single dose of an enhanced Modified Vaccinia Ankara (MVA) vaccine, designated MVA-X, provided durable protection against highly pathogenic Clade I mpox virus and other orthopoxviruses. The findings, which showed protection lasting at least 150 days and comparable to a conventional two-dose MVA regimen, could significantly simplify vaccination campaigns during outbreaks and enhance biosecurity preparedness.
The study, titled “Single-dose Efficacy of a Next-Generation Mpox Vaccine Harnessing an Immunomodulatory Peptide,” was conducted in collaboration with Washington State University and funded by GeoVax. The manuscript is available as a preprint at bioRxiv. In the reported studies, a single MVA-X vaccination provided complete protection following lethal and high-dose orthopoxvirus challenge at Days 55, 90, and 150; restricted viral replication and systemic dissemination; generated durable antigen-specific CD8+ T-cell responses despite declining antibody levels; and protected highly susceptible animals against lethal Clade I mpox challenge.
The implications of these findings are substantial. Currently, MVA-based mpox vaccination generally requires a two-dose regimen. Reducing that to a single dose could streamline deployment, accelerate completion of vaccination programs, and reduce the logistical burden of protecting at-risk populations, especially in resource-constrained settings or during outbreaks. David Dodd, Chairman and CEO of GeoVax, commented, “During an outbreak, reducing a two-dose regimen to a single vaccination could simplify deployment, accelerate completion of vaccination programs and reduce the logistical burden associated with protecting at-risk populations.”
Beyond mpox, the research supports a broader strategy to expand the utility of the MVA platform. GeoVax is advancing innovations in dosing, manufacturing, and administration. In parallel with MVA-X, the company is developing continuous cell-line manufacturing and evaluating needle-free microarray patch delivery. These initiatives aim to improve the operational flexibility of MVA-based vaccines for global health, outbreak response, and biosecurity. Mark Newman, Ph.D., Chief Scientific Officer of GeoVax, noted, “These data point toward an innovative approach to augmenting MVA potency and provide support for the important role of the cellular arm of the immune system, particularly CD8-positive T-cell responses, in controlling and clearing orthopoxvirus infection.”
GeoVax’s priority program, GEO-MVA, is an MVA-based vaccine targeting mpox and smallpox that is advancing under an expedited regulatory pathway, with plans to initiate a pivotal Phase 3 clinical trial in the second half of 2026. The MVA-X research represents one element of GeoVax’s broader effort to advance the utility of MVA-based vaccines. The company maintains a global intellectual property portfolio supporting its infectious disease and oncology programs. For more information, visit www.geovax.com.
The manuscript is a preprint and has not been certified by peer review. Findings from preclinical animal studies may not be predictive of results in humans.
