This study is researching an experimental drug called REGN10597 alone or in combination with another drug called cemiplimab (called "study drug(s)"). The study is focused on patients with certain solid tumors that are in an advanced stage. The aim of the study is to see how safe, tolerable, and effective the study drug(s) are. The study is looking at several other research questions, including: * What side effects may happen from taking the study drug(s) * How much study drug(s) is in the blood at different times * Whether the body makes antibodies against the study drug(s) (which could make the study drug(s) less effective or could lead to side effects)