SAN DIEGO, April 14, 2011 (GLOBE NEWSWIRE) -- Vical Incorporated (Nasdaq:VICL) announced today the issuance of European Patent EP1587816, which extends coverage for TransVax™, the company's first-in-class therapeutic DNA vaccine designed to prevent reactivation of latent cytomegalovirus (CMV) or introduction of CMV through donor cells or tissues in transplant recipients.