A Safety Trial of MVA-BN®-PRO in Men With Androgen-Insensitive Prostate Cancer

MVA-BN®-PRO is a candidate prostate cancer immunotherapy product comprised of a highly attenuated non-replicating vaccinia virus, MVA-BN®, engineered to encode prostate specific antigen (PSA) and prostate acid phosphatase (PAP) proteins. The MVA-BN®-based vaccine provides innate and adaptive immune activating factors, and vaccination by this strategy will be evaluated for its capacity to help override self and tumor tolerance mechanisms. Previous work has shown PSA and PAP antigens to be immunogenic in humans when presented with immune stimulatory components. Multiple clinical studies have demonstrated promising activity of PSA-targeted vaccinia-based immunotherapy. Additionally, PAP-based cellular therapy immunization approaches, have shown promise in Phase III clinical trials and provided for enhanced survival. The strategy undertaken by BNIT is to combine both antigens in the MVA-BN® vector to enhance the immunogenic effect and to help mitigate development of tumor resistance. This trial examines three vaccination regimens of MVA-BN®-PRO: Vaccine is provided at (0.5cc/dose/1x10e8 TCID50) * Cohort 1: 1 sc injection every 4 weeks x 3; retreated once at the same dose and schedule. * Cohort 2: 2 sc injections every 4 weeks x 3; retreated once at the same dose and schedule. * Cohort 3: 4 sc injections every 4 weeks x 3; retreated once at the same dose and schedule. These dose regimens are based on the current dose of MVA-BN® (1x10e8 TCID50 by sc injection) under development as a prophylactic vaccine for the prevention of smallpox, and on related clinical studies of MVA-nef-based vaccines (5x10e8 TCID50) for induction of heterologous immunity.