CTLA4 and breast cancer: (modified vaccinia Ankara) MVA-BN-Brachyury/(fowlpox virus)FPV-BN-brachyury vaccine is well tolerated and induces immune responses to brachyury and cascade antigens and demonstrates some evidence of clinical benefit in solid tumors (95).In a study by Gao et al., a combination of recombinant oncolytic virus with CTLA-4 antibodies targeted HER2 breast cancer cells.