Trametinib, sold under the brand name Mekinist, is an orally administered targeted anticancer drug that works by selectively inhibiting MEK1 and MEK2, essential components of the RAS/RAF/MEK/ERK signaling pathway that regulates cancer-cell proliferation and survival. Originally developed as GSK1120212 and later advanced by GlaxoSmithKline, trametinib entered clinical development in 2008 and gained FDA approval in May 2013 as the first MEK inhibitor for patients with unresectable or metastatic melanoma harboring BRAF V600E or V600K mutations. It is frequently combined with dabrafenib, a BRAF inhibitor, to achieve more complete and durable suppression of the MAPK pathway, and its approved uses have since expanded to include BRAF-mutated non-small cell lung cancer, anaplastic thyroid cancer, certain pediatric low-grade gliomas, and selected BRAF V600E-mutant solid tumors. Although trametinib has substantially improved treatment outcomes in BRAF-driven cancers, clinicians monitor patients for adverse effects including rash, diarrhea, peripheral edema, cardiomyopathy, ocular toxicity, and interstitial lung disease.
