GeoVax Completes Enrollment of Phase 2 Trial for Next-Generation COVID-19 Vaccine Booster

Multi-antigen Vaccine Designed to Protect Against Evolving SARS-CoV-2 Variants

ATLANTA, GA, September 11, 2023 – GeoVax Labs, Inc. (Nasdaq: GOVX), a biotechnology company developing immunotherapies and vaccines against cancers and infectious diseases, today announced that it has met the enrollment target for its Phase 2 clinical trial evaluating GEO-CM04S1 as a booster for healthy patients who have previously received the Pfizer or Moderna mRNA vaccine (ClinicalTrials.gov Identifier: NCT04639466).

The study is designed to evaluate the safety profile and immunogenicity of two GEO-CM04S1 dose levels administered as a COVID-19 vaccine booster among healthy individuals previously vaccinated with one of the FDA approved SARS-CoV-2 mRNA vaccines. The immunological responses measured throughout the study will include both the level of neutralizing antibodies against SARS-CoV-2 variants of concern and specific T cell responses.

GEO-CM04S1 is a next-generation COVID-19 vaccine based on GeoVax’s MVA viral vector platform, which supports the presentation of multiple vaccine antigens to the immune system in a single dose. GEO-CM04S1 encodes for both the spike (S) and nucleocapsid (N) antigens of SARS-CoV-2 and is specifically designed to induce both antibody and T cell responses to those parts of the virus less likely to mutate over time. The more broadly functional engagement of the immune system is designed to protect against severe disease caused by continually emerging variants of COVID-19. Vaccines of this format should not require frequent and repeated modification or updating.

“We would like to thank everyone who partnered with us to complete this important clinical trial enrollment milestone, especially the study volunteers and research staff at our clinical sites in the United States,” said David Dodd, GeoVax Chairman and CEO. “We believe the unique properties of GEO-CM04S1 potentially offer a more robust, durable degree of protection than the current authorized COVID-19 vaccines, not only as a booster vaccine to the currently authorized mRNA vaccines, but as a primary vaccine for highly vulnerable immunocompromised patients.”

Additional Ongoing Trials of GEO-CM04S1

In addition to the booster vaccine trial for which patient enrollment was just completed, GEO-CM04S1 is being evaluated in two other Phase 2 clinical trials:

  • As a primary vaccine in immunocompromised patients (with hematologic cancers receiving cell transplants or CAR-T therapy). ClinicalTrials.gov Identifier: NCT04977024. A recent presentation of unpublished data from the open-label portion of the trial indicates that GEO-CM04S1 is highly immunogenic in these patients, inducing both antibody responses, including neutralizing antibodies, and T cell responses. These data support the progression of the Phase 2 clinical study, which includes a direct comparison to currently approved mRNA vaccines.
  • As a booster vaccine in immunocompromised patients with chronic lymphocytic leukemia (CLL), a recognized high-risk group for whom current mRNA vaccines and monoclonal antibody (MAb) therapies appear inadequate relative to providing protective immunity. ClinicalTrials.gov Identifier: NCT05672355.

Further underscoring the need for next-generation COVID-19 vaccines such as GEO-CM04S1, GeoVax scientists co-authored an article titled, “ MVA-Vectored Universal Beta-Coronavirus Vaccine Design & Development ”, published in the June 2023 issue of the online journal Vaccine Insights. The article, accessible here, provides expert insight into the emergence of SARS-CoV-2 (COVID-19), the risk of new “spillover events” from animal hosts, and how this risk can be addressed proactively. Regarding COVID-19 and its continually evolving variants, the authors describe the limitations of first-generation vaccines and the potential for MVA-vectored vaccines such as GEO-CM04S1 to overcome these limitations.

GeoVax Labs, Inc. is a clinical-stage biotechnology company developing novel therapies and vaccines for solid tumor cancers and many of the world’s most threatening infectious diseases. The company’s lead program in oncology is a novel oncolytic solid tumor gene-directed therapy, Gedeptin ® , presently in a multicenter Phase 1/2 clinical trial for advanced head and neck cancers. GeoVax’s lead infectious disease candidate is GEO-CM04S1, a next-generation COVID-19 vaccine targeting high-risk immunocompromised patient populations. Currently in three Phase 2 clinical trials, GEO-CM04S1 is being evaluated as a primary vaccine for immunocompromised patients such as those suffering from hematologic cancers and other patient populations for whom the current authorized COVID-19 vaccines are insufficient, and as a booster vaccine in patients with chronic lymphocytic leukemia (CLL). In addition, GEO-CM04S1 is in a Phase 2 clinical trial evaluating the vaccine as a more robust, durable COVID-19 booster among healthy patients who previously received the mRNA vaccines. GeoVax has a leadership team who have driven significant value creation across multiple life science companies over the past several decades. For more information, visit our website: www.geovax.com.

Forward-Looking Statements

This release contains forward-looking statements regarding GeoVax’s business plans. The words “believe,” “look forward to,” “may,” “estimate,” “continue,” “anticipate,” “intend,” “should,” “plan,” “could,” “target,” “potential,” “is likely,” “will,” “expect” and similar expressions, as they relate to us, are intended to identify forward-looking statements. We have based these forward-looking statements largely on our current expectations and projections about future events and financial trends that we believe may affect our financial condition, results of operations, business strategy and financial needs. Actual results may differ materially from those included in these statements due to a variety of factors, including whether: GeoVax is able to obtain acceptable results from ongoing or future clinical trials of its investigational products, GeoVax’s immuno-oncology products and preventative vaccines can provoke the desired responses, and those products or vaccines can be used effectively, GeoVax’s viral vector technology adequately amplifies immune responses to cancer antigens, GeoVax can develop and manufacture its immuno-oncology products and preventative vaccines with the desired characteristics in a timely manner, GeoVax’s immuno-oncology products and preventative vaccines will be safe for human use, GeoVax’s vaccines will effectively prevent targeted infections in humans, GeoVax’s immuno-oncology products and preventative vaccines will receive regulatory approvals necessary to be licensed and marketed, GeoVax raises required capital to complete development, there is development of competitive products that may be more effective or easier to use than GeoVax’s products, GeoVax will be able to enter into favorable manufacturing and distribution agreements, and other factors, over which GeoVax has no control.

Further information on our risk factors is contained in our periodic reports on Form 10-Q and Form 10-K that we have filed and will file with the SEC. Any forward-looking statement made by us herein speaks only as of the date on which it is made. Factors or events that could cause our actual results to differ may emerge from time to time, and it is not possible for us to predict all of them. We undertake no obligation to publicly update any forward-looking statement, whether as a result of new information, future developments or otherwise, except as may be required by law. 

Contact:

GeoVax Labs, Inc.

678-384-7220

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