Targeting FAK/MEK to Potentiate Immune Checkpoint Inhibition in Melanoma

Why This Research Matters
Melanoma is the deadliest form of skin cancer because it spreads to the lungs, brain, and other organs. Even though powerful new treatments including immunotherapy drugs that boost the body’s own defenses and targeted pills that block cancer growth signals have been approved in recent years, many patients either never respond or stop responding within months. Once the cancer reaches the brain, options are especially limited and survival is often short.

What We Are Studying
Our laboratory discovered that a protein called FAK acts like a “shield” for melanoma cells. It helps the cancer spread to the brain, hides it from the immune system, and makes both immunotherapy and targeted drugs less effective. In sophisticated mouse models that closely mimic the human disease, we showed that blocking FAK with the drug defactinib, together with a new targeted drug called avutometinib, dramatically shrinks tumors and stops spread to the brain. Most excitingly, adding standard immunotherapy to this combination produced lasting cures in 75% of the mice, with the immune system remembering and fighting the cancer even after treatment stopped.

How the Study Works
Building on these results, we have already launched a small clinical trial (DETERMINE) testing defactinib and avutometinib, with or without the BRAF inhibitor encorafenib, in patients with melanoma that has spread to the brain. Early results show the drugs are safe and have caused tumor shrinkage including one patient whose brain tumors and symptoms improved for almost a year. This new clinical trial will take the next critical step: a phase 1 safety trial that carefully adds immunotherapy to the targeted drugs in two groups of patients. One group will receive the four-drug combination for any type of advanced melanoma; the second group will add encorafenib for patients whose tumors carry the common BRAF mutation. Using a modern, efficient dose-finding method, we will test small groups of patients starting at safe doses and slowly increase them while closely monitoring side effects. The main goal is to confirm the combination is safe and tolerable. We will also look for early signs that it controls brain and body tumors better and for longer than current treatments.

Expected Impact
If successful, this innovative “quadruple” or “quintuple” approach could give patients with advanced melanoma, especially those with brain metastases, longer, higher-quality lives by simultaneously attacking the cancer’s growth signals, removing its protective shield, and unleashing the immune system. It represents a new strategy to overcome treatment resistance and could change how we combine targeted and immune therapies for many hard-to-treat cancers.