This study tests a new drug called RMC-6236 for adults with advanced solid tumors that have specific RAS mutations. RAS is a group of genes that, when mutated, can lead to cancer. The study is in Phase 1/2, meaning it's early in testing and involves multiple research centers. The goal is to find out how safe the drug is, how the body processes it, and how it affects tumors. Researchers will determine the highest safe dose, known as the maximum tolerated dose (MTD), and the best dose to use in the next phase.

• Participants must have specific gene changes, called mutations, identified in their tumor.
• The study is open-label, so both doctors and participants know the treatment being given.
• Participants cannot have certain conditions, like untreated brain issues or difficulty swallowing pills.