This study is evaluating how safe, tolerable and effective a new type of immunotherapy is in people with advanced cutaneous squamous cell carcinomaA Phase 2 Study Evaluating INCB099280 in Participants With Advanced Squamous Cell Carcinoma

Exclusion

• Known history of an additional malignancy.
• Central nervous system (CNS) metastases requiring treatment and/or leptomeningeal disease.
• Toxicity from prior therapy that has not recovered.
• Prior receipt of an anti-PD-1, anti-PD-L1, or anti-PD-L2 agent; treatment with an immune modulator (eg, CTLA-4, GITR, LAG3, TIM3, OX40, ICOS, IL-2, 4-1BB, CAR-T cell).
• Received thoracic radiation within 6 months of the first dose of study treatment.
• Participation in another interventional clinical study while receiving INCB099280.
• Impaired cardiac function or clinically significant cardiac disease.
• History or evidence of interstitial lung disease including noninfectious pneumonitis.
• Presence of gastrointestinal conditions that may affect drug absorption.
• Any autoimmune disease requiring systemic treatment in the past 5 years.
• Diagnosis of primary immunodeficiency or receiving chronic systemic steroid therapy at a daily dose exceeding 10 mg of prednisone or equivalent.
• Active infection requiring systemic therapy.
• History of organ transplantation, including allogeneic stem cell transplantation.
• Receipt of systemic antibiotics within 28 days of first dose of study treatment.
• Probiotic usage is prohibited during screening and throughout the study treatment period.
• Received a live vaccine within 28 days of the planned start of study drug.
• Laboratory values outside the Protocol-defined ranges.
• Inadequate organ function.

Other protocol-defined Inclusion/Exclusion Criteria may apply.