Overview Pembrolizumab in Metastatic Anal Cancer Status: Recruiting Trial end date: 2023-03-01 Target enrollment: Participant gender: Summary This research study is studying a targeted therapy as a possible treatment for advanced anal cancer. The following intervention will be involved in this study: -Pembrolizumab Phase: Phase 2 Details Lead Sponsor: Dana-Farber Cancer InstituteCollaborator: Merck Sharp & Dohme Corp.Treatments: Pembrolizumab