A Study of SAR444245 Combined With Cemiplimab for the Treatment of Participants With Various Advanced Skin Cancers (Pegathor Skin 201)

Inclusion Criteria: * Participant must be ≥18 years of age (or country's legal age of majority if \>18 years), at the time of signing the informed consent. * Participants with: * Cohort A: Histologically confirmed unresectable locally advanced or metastatic melanoma that are not amenable to local therapy * Cohort B: Histologically confirmed metastatic CSCC or locally advanced * CSCC that are not candidates for curative surgery or radiation. Special considerations for the following categories: Participants with tumors arising on the cutaneous hair (non-glabrous) bearing lip with extension onto dry red lip (vermillion) may be eligible after communication with and approval from the Sponsor Participants with the primary site is nose are only eligible if the primary site was skin, not nasal mucosa with outward extension to skin (the Investigator confirmed) Participants with mixed histology in which the predominant histology is invasive CSCC may be eligible after communication with and approval from the Sponsor * Participants in both cohorts must have at least one measurable lesion * Provision of tumor tissue: For participants in the dose escalation: 16 µg/kg: at screening, biopsy is optional but highly recommended; and on-treatment not required 24 µg/kg: at screening, biopsy is mandatory and on-treatment, optional but highly recommended * For the other participants : Mandatory baseline biopsy for the participants to enroll in cohort A with skin metastasis and in cohort B.…