An Early Access Program Guideline to Provide Access to Retifanlimab (INCMGA00012) Together With Carboplatin and Paclitaxel for Squamous Carcinoma of the Anal Canal (SCAC)

Inclusion Criteria: * Able to comprehend and willing to sign a written ICF for the study. * Are 18 years of age or older (or as applicable per local country requirements). * Histologically or cytologically verified, inoperable locally recurrent or metastatic SCAC. * Adequate ECOG performance status to be able to benefit from the treatment. * If HIV-positive, a well controlled and stable disease and receiving antiretroviral therapy (ART/HAART) and have not experienced any HIV-related opportunistic infection for at least 4 weeks prior to study enrollment. * Willingness to avoid pregnancy or fathering children based on the criteria below. * Men must agree to take appropriate precautions to avoid fathering children (with at least 99% certainty) from screening through 120 days after the last dose of INCMGA00012 or placebo or through 180 days after the last dose of chemotherapeutic agents, whichever occurs later (or longer as appropriate based on country-specific requirements) and must refrain from donating sperm during this period. Permitted methods that are at least 99% effective in preventing pregnancy should be communicated to the participants and their understanding confirmed. * Women of childbearing potential must have a negative serum pregnancy test at screening, agree to take appropriate precautions to avoid pregnancy (with at least 99% certainty), and refrain from donating oocytes from screening through 120 days after the last dose of INCMGA00012 or placebo or throug…