Our Hepatitis B Therapeutic Vaccine Program

About Hepatitis B disease:

Hepatitis B is a contagious liver disease caused by the Hepatitis B virus (HBV).  It is transmitted person-to-person by blood, semen, or other bodily fluids.  This can happen through sexual contact, needle sharing, or mother to infant transmission during birth.  For some people, Hepatitis B is an acute (or short-term) illness; but for others, it can become a long-term, chronic infection that may lead to serious health issues like cirrhosis or liver cancer.  The risk of chronic infection is related to age at infection.  Approximately 90% of infected infants will develop chronic infections.  As a child gets older, the risk decreases. Approximately 25-50% of children infected between the ages of 1 and 5 years will develop chronic hepatitis.  The risk drops 6%-10% when a person is infected over 5 years of age.  Worldwide, most people with chronic Hepatitis B were infected at birth or during early childhood.

The CDC estimates that between 700,000 to 1.4 million people in the United States have chronic HBV infections, with an estimated 20,000 new infections every year.  Many people are unaware that they are infected or may not show any symptoms.   Therefore, they never seek the attention of medical or public health officials.  Globally, chronic Hepatitis B affects more than 240 million people and contributes to nearly 686,000 deaths worldwide each year.  Even though a preventive HBV vaccine is available, less than 5% of chronic HBV infections are cured.

GeoVax Hepatitis B Therapeutic Program

There is a clear medical need to treat chronic HBV infections, which affect hundreds of millions of people around the world, many of whom die due to complications of HBV including cirrhosis and cancer.  Multiple vaccines exist to protect against HBV infection, but they cannot help patients already diagnosed with the disease.  Although chronic HBV can be treated with drugs, the treatments do not cure 95% of patients; they cannot induce strong neutralizing antibodies and cellular responses needed to break tolerance to HBV antigens and clear infections, but only suppress the replication of the virus.  Therefore, most people who start treatments must continue with them for life.  Moreover, diagnosis and treatment options are very limited in resource/low income-constrained populations, which leads to many patients succumbing within months of diagnosis.

Patients with undetectable HBV-DNA shown to have responded mainly with IgG1 and/or IgG3, while in the HBV-DNA-positive group, a high contribution of IgG4 was found.  The correlation of protection is mainly induction of CD4+ response to core and IgG3 response to S antigens (Gregorek, et al 2015). Our HIV data shows that the DNA and MVA-VLP produced strong CD4+ response and high ratio of IgG3.  GeoVax's combination therapeutic vaccine strategy comprises of multivalent vaccine antigens delivered by DNA and MVA-VLP in combination with the standard-of-care treatment to induce functional antibodies and CD4+, CD8+ T cell responses to clear infection and break tolerance needed toward a functional cure.  Our goal is to significantly increase the current cure rate of HBV infections while reducing the duration of drug therapy, overall treatment costs, side effects, and potential drug resistance.

We have entered a Research Collaboration Agreement with Georgia State University Research Foundation (GSU) to advance the Company's development of a therapeutic vaccine for treatment of chronic Hepatitis B Virus (HBV) infections (Press Release). The project will include the design, construction, characterization and animal testing of multiple vaccine candidates using GeoVax's MVA-VLP vaccine platform.  Vaccine antigens include both GeoVax and GSU's proprietary designed sequences.  The vaccine design, construction, and characterization were performed at GeoVax with further characterization and immunogenicity studies in mice conducted at GSU.  Unique functional assays developed by Dr. Ming Luo, Professor in the Department of Chemistry at Georgia State University, and performed at Peking University will provide key information on vaccine efficacy.