RecruitingPhase 2Biological interventionIntratumoral Vusolimogene Oderparepvec (VO) in Combination With Pembrolizumab for AngiosarcomaThis is a multicenter, open-label study of Intratumoral Vusolimogene Oderparepvec (VO) to investigate safety and estimate when used in combination with pembrolizumab for treating participants with angiosarcoma. This is the first study evaluating this novel combination in participants with advanced angiosarcoma who have progressed after prior immunotherapy.