Genital Herpes Vaccine Shows Promise in Mid-Stage Trial
Viral shedding reduced after three injections (November 7)
Positive results have been reported from a phase II randomized double-blind study of HerpV (Agenus Inc.), a recombinant “off-the-shelf” therapeutic vaccine candidate for the treatment of patients with herpes simplex virus-2 (HSV-2) infection. HerpV contains a mixture of peptides representing HSV-2 antigens plus an adjuvant.
The study measured genital viral shedding 45 days before and after three injections of HerpV. The primary analysis, which looked at viral shedding after the initial three injections, shows that subjects who received HerpV had a statistically significant reduction in viral shedding compared with subjects given placebo (P = 0.015). These results indicate a 15% reduction (relative risk, 0.85) in viral shedding after the initial treatment period before the administration of the booster injection. The results also demonstrate a reduction in viral load of 34% (P = 0.08). Subjects given placebo showed no reduction compared with baseline in either parameter.
Most of the subjects in the study have received a booster injection of HerpV, which was given 6 months after the first vaccination, followed by determination of genital viral shedding for an additional 45-day period. Post-booster viral shedding results, along with immune-response data, are anticipated in the first half of 2014.
Source: Agenus Inc.; November 7, 2013.