Study of REGN2810 in Patients With Advanced Cutaneous Squamous Cell Carcinoma

Key Inclusion Criteria: * At least 1 measurable lesion * Eastern Cooperative Oncology Group (ECOG) performance status ≤1 * Adequate bone marrow function * Adequate renal function * Adequate hepatic function * Archived or newly obtained tumor material * Patients must consent to undergo biopsies of CSCC lesions (Groups 2, 4, and 6) * Surgical or radiological treatment of lesions contraindicated Key Exclusion Criteria: * Ongoing or recent (within 5 years) evidence of significant autoimmune disease that required treatment with systemic immunosuppressive treatments, which may suggest risk for immune-related adverse events * Prior treatment with an agent that blocks the PD-1/PD-L1pathway * Prior treatment with a BRAF inhibitor * Prior treatment with other immune-modulating agents within fewer than 4 weeks prior to the first dose of cemiplimab, or associated with immune-mediated adverse events that were ≥ grade 1 within 90 days prior to the first dose of cemiplimab, or associated with toxicity that resulted in discontinuation of the immune-modulating agent. Examples of immune-modulating agents include therapeutic vaccines, cytokine treatments, or agents that target cytotoxic T-lymphocyte antigen 4 (CTLA-4), 4-1BB (CD137), or OX-40. * Untreated brain metastasis(es) that may be considered active * Immunosuppressive corticosteroid doses (\>10 mg prednisone daily or equivalent) within 4 weeks prior to the first dose of cemiplimab * Infection with human immunodeficiency virus (HIV) an…