CMV seropositive subjects undergoing HCT procedures will be enrolled in the double-blind, placebo-controlled trial, which will randomise them in a 1:1 ratio by stratifying donor-recipient relatedness and donor CMV serostatus.
Vical president and chief executive officer Vijay Samant said ASP0113 has become the first investigational therapeutic CMV vaccine to reach Phase III testing.
"Therapeutic vaccines, designed to control disease in people with established and persistent infections, represent the highest hurdle in vaccinology," Samant added.
"We are excited to achieve this important milestone as we continue advancing ASP0113 toward commercialisation."
With overall survival at one year as the primary endpoint, the first part of the trial will enrol approximately 100 subjects.
The primary endpoint of the second part, which will enrol around 400 subjects, will be either survival or a composite endpoint, including survival and other variables, depending on the statistical analysis of first part results, and is expected to be determined by the time of enrolment completion.
After the completion of enrolment, each subject will be treated and observed for one year as part of the study.
Under the exclusive worldwide licence agreement signed between the companies in 2011 to develop and commercialise ASP0113, Astellas is carrying out the study and Vical is providing development, regulatory and manufacturing support.
An additional Phase II trial of ASP0113 in solid organ transplant (SOT) recipients is expected to commence later in 2013.
Image: CMV infection of a lung pneumocyte. Photo courtesy of MarcoTolo at en.wikipedia.