Phase II Study of the MEK1/MEK2 Inhibitor Trametinib in Patients With Metastatic <i>BRAF</i> -Mutant Cutaneous Melanoma Previously Treated With or Without a BRAF Inhibitor

Abstract

Trametinib was well tolerated. Significant clinical activity was observed in BRAF-inhibitor-naive patients previously treated with chemotherapy and/or immunotherapy. Minimal clinical activity was observed as sequential therapy in patients previously treated with a BRAF inhibitor. Together, these data suggest that BRAF-inhibitor resistance mechanisms likely confer resistance to MEK-inhibitor monotherapy. These data support further evaluation of trametinib in BRAF-inhibitor-naive BRAF-mutant melanoma, including rarer forms of BRAF-mutant melanoma.