April 5, 2011
Possible Vaccine for Viral Hep C
(Ivanhoe Newswire) -- Early data from phase I trials of an HCV vaccine show encouraging results, with high immunogenicity and good safety profile.
In the first study, a therapeutic T-cell vaccine, based on novel adenoviral vectors, was used on a small population of treatment naive patients with chronic genotype 1 HCV infection. Intra-muscular vaccination was administered 2 or 14 weeks into a 48-week course of treatment with Peg-IFNa2a/ribavirin. Fifty percent of vaccinated patients had CD4+ and CD8+ HCV specific T-cell responses as detected by ELISpot at 2-8 weeks post boost, showing a strong immunogenicity for the vaccine. Local and systemic adverse events to vaccination were mild, with no evidence of liver immunopathology (measured by liver transaminase levels).The second study looked at the potential for a prophylactic vaccine based on similar, novel adenoviral vectors technology (replicative-defective human Ad6 and a novel simian AdCh3 vector that encode 1985 amino-acids derived from the NS3-5 region of a genotype-1b strain). Twenty-seven healthy volunteers were vaccinated following a double prime, heterologous boost strategy. The vaccine induced polyfunctional CD4+ and CD8+ T cells responses, which were maintained up to 52 weeks post prime. Overall vaccination was very well tolerated with mild/moderate local and systemic 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," Professor Heiner Wedemeyer, EASL's Secretary General, was quoted as saying. "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."
SOURCE: International Liver Congress held in Berlin, Germany, March 30- April 3, 2011