Progress reported on hepatitis C vaccine

Early data presented at the International Liver Congress on the phase I trials of a viral hepatitis C vaccine have shown encouraging results with a good safety profile and high immunogenicity.

The first study used a therapeutic T-cell vaccine that was based on adenoviral vectors to treat patients with chronic genotype 1 HCV infection. The intramuscular vaccination was administered two or 14 weeks into a 48 week course of treatment along with Peg-IFNa2a/ribavirin.

Half of the vaccinated patients had CD4+ and CD8+ HCV specific T-cell responses, which led to a strong immunogenicity for the vaccine. Only mild adverse events to the vaccinations were detected and there was no evidence of liver immunopathology.

The second study evaluated the potential for a prophylactic vaccine based on a similar novel technology of adenoviral vectors. Twenty-seven healthy volunteers were vaccinated using a double prime, heterologous boost strategy.

The vaccine led to polyfunctional CD4+ and CD8+ T-cell responses, which were maintained for up to 52 weeks post prime.

Overall, the vaccination was well tolerated with mild to moderate systemic and local reactions and no serious adverse advents.

"Vaccines are an exciting area of research now with the potential to add to the range of treatments available for patients with chronic viral hepatitis,” Heiner Wedemeyer, a professor and the European Association for the Study of the Liver’s secretary general, said. “These are early data but results are very encouraging indeed and as experts, we look forward to more scientific evidence being made available to support this new technology as a future treatment option as well as potentially preventing infection."

While previous research that had showed potent and durable T-cell responses, this was the first time the safety and immunogenicity of a vaccination was tested on both healthy subjects and HCV patients.