Phase 1b, Multicenter, Open-label, Dose Escalation and Dose Expansion Study of RMC-6291 in Combination with RMC-6236 in Participants with Advanced KRASG12C-mutated Solid Tumors

• RMC-6291 is a tri-complex inhibitor of the active GTP-bound state of the mutated KRASG12C protein
• RMC-6236 is a RASMULTI(ON) inhibitor

In this study, the sponsor and investigators want to learn:

• How much of the study drugs can be given in combination with an acceptable level of side effects
• The effects of the study drugs (good and bad)
• How much of the study drugs are absorbed into the blood and how fast they are removed
• How the study drugs are acting on your body

This is a dose escalation/expansion study. Dose Escalation means that the amount of the RMC-6291 and RMC‑6236 given will be increased in each group of research participants, to find the most appropriate dose for further study.  In the dose expansion part of the study, a larger number of people receive the RMC-6291 and RMC‑6236 dose determined to be appropriate in the dose escalation part of the study.

The study regimen will be given in cycles.  Each cycle is 21 days.  You will receive RMC-6291 twice daily by mouth. You will receive RMC‑6236 once daily by mouth.