DEVELOPMENT OF THE FORMALIN-INACTIVATED HEPATITIS-A VACCINE, VAQTA(TM) FROM THE LIVE ATTENUATED VIRUS-STRAIN CR326F

The development of the formalin-inactivated hepatitis A vaccine, VAQTA (TM), culminates nearly two decades of the basic science studies of VA QTA(TM) in hepatitis A virology at the MRL. The master seed virus for production of VAQTA(TM) is derived from the F'(P18) variant of the str ain CR326F which has been studied in human clinical trials and shown t o the highly attenuated. The antigen is highly purified to make possib le the consistency and thoroughness of its inactivation by formalin. P hase I clinical studies of VAQTA(TM) were initiated in 1989 and have p rogressed since that time to the recent Phase III clinical trials whic h demonstrated efficacy of a single dose of the vaccine in preventing clinical hepatitis A disease in pediatric populations in Monroe, NY.