Small Molecule B-RAF Inhibitors as Anti-Cancer Therapeutics: Advances in Discovery, Development, and Mechanistic Insights

B-RAF is a serine/threonine kinase that plays a crucial role in the MAPK signaling pathway, regulating cell proliferation and survival. Mutations in B-RAF, particularly V600E, are associated with several malignancies, including melanoma, colorectal cancer, and non-small cell lung cancer, making it a key therapeutic target. The development of B-RAF inhibitors, such as Vemurafenib, Dabrafenib, and second-generation inhibitors like Encorafenib, has led to significant advancements in targeted cancer therapy. However, acquired resistance, driven by MAPK pathway reactivation, RAF dimerization, and alternative signaling pathways, remains a major challenge. This review explores the molecular mechanisms of B-RAF inhibitors, their therapeutic efficacy, and resistance mechanisms, emphasizing the importance of combination strategies to enhance treatment outcomes. The current standard of care involves B-RAF and MEK inhibitors, with additional therapies such as EGFR inhibitors and immune checkpoint blockades showing potential in overcoming resistance. Emerging pan-RAF and brain-penetrant inhibitors offer new opportunities for treating refractory cancers, while precision medicine approaches, including genomic profiling and liquid biopsies, are shaping the future of B-RAF-targeted therapy.