Investigational DNA vaccine in unsuccessful trial

Astellas Pharma and Vical announced that ASP 0113, an investigational DNA vaccine being developed for cytomegalovirus (CMV)-seropositive hematopoietic stem cell transplant (HSCT) recipients, did not meet its primary or secondary endpoints in the Phase III HELIOS clinical trial. The vaccine was generally well tolerated, with injection-site reactions being the most commonly reported adverse event.

The Phase III trial was designed to evaluate the efficacy of ASP0113 compared with placebo in CMV-seropositive recipients undergoing an allogeneic stem cell transplant. Efficacy was assessed using a primary composite endpoint of overall mortality and CMV end-organ disease through the first year following the transplant, an endpoint which was not met. Secondary endpoints of time to first protocol-defined CMV viremia and time to first use of adjudicated CMV-specific antiviral therapy also were not met.