ASP0113 (formerly TransVax™) is a potentially first-in-class investigational DNA vaccine designed to prevent
reactivation of latent cytomegalovirus (CMV) or introduction of the
virus through donor cells or tissues in transplant recipients. The investigational product is in late-stage development; proof-of-concept in achieving CMV
viral load reduction has now been shown in susceptible hematopoietic cell transplant (HCT) patients.
In July 2011, Vical entered into license agreements with Astellas Pharma Inc. granting Astellas an exclusive, worldwide, royalty-bearing license to develop and commercialize ASP0113 for the control and prevention of cytomegalovirus infection in immunocompromised patients, including transplant recipients, and transplant donors. Under the agreements, Astellas will be responsible for further development and commercialization, including all costs. Vical will provide assistance to Astellas with ASP0113-related manufacturing, regulatory and certain development activities, for which Astellas will reimburse all of Vical's future costs, including personnel and external expenses. Vical will receive up to $130 million in total upfront and milestone payments through commercial launch, including $25 million upfront and $10 million upon finalization of the Phase 3 trial design. Vical has an option to co-promote ASP0113 in the United States, and potentially will receive double-digit royalties on net sales. The companies initiated a multinational Phase 3 registration trial of ASP0113 in HCT recipients in June 2013 and expect to initiate a Phase 2 trial in solid organ transplant (SOT) recipients in the second half of 2013.
Currently there is no marketed CMV vaccine. The only approved antiviral treatment for CMV in HCT patients is Cytovene®
(ganciclovir), although other antivirals (i.e., valganciclovir) are used off-label. A vaccine that enables the patient's immune system to control CMV reactivation, reducing the risk of complications from antiviral therapy and CMV disease, would provide a valuable therapeutic option for HCT and solid organ transplant (SOT) recipients.
HCT and SOT recipients represent important populations for the prevention of CMV reactivation and reduction in antiviral therapy. Nearly 60,000 HCT procedures will be performed annually in the United States and Europe by 2015, along with about the same number of SOT procedures. These populations represent a significant market potential for ASP0113.