Information about Vemurafenib
Vemurafenib is a selective inhibitor of BRAF kinase that is used in the therapy of patients with metastatic and advanced malignant melanoma.
Liver safety of Vemurafenib
Vemurafenib therapy is commonly associated with transient elevations in serum aminotransferase during therapy and has been linked to rare, but occasionally severe cases of clinically apparent acute liver injury.
Mechanism of action of Vemurafenib
Vemurafenib (vem’ ue raf” e nib) is an orally available inhibitor of mutated forms of BRAF, a serine/threonine kinase that is a component of the mitogen-activated pathway (MAP) kinases which are important intracellular signals involved in control of cell growth and proliferation. BRAF kinase is an early step in the cascade of MAP kinases (RAS-RAF-MEK-ERK) and is frequently mutated in malignant conditions, including at least half of cases of melanoma. Vemurafenib was shown to be active against the V600E mutants of BRAF in vitro and in animal models. Furthermore, in clinical trials vemurafenib therapy was associated with an improvement in overall survival in patients with metastatic malignant melanoma with V600E mutations.
FDA approval information for Vemurafenib
Vemurafenib was approved for use in the United States in 2011 and current indications are for unresectable or metastatic melanoma with the BRAF V600E mutation and Langerhans-cell histiocytosis with BRAF V600 mutations.
Dosage and administration for Vemurafenib
Vemurafenib is available in tablets of 240 mg under the brand name Zelboraf. The typical dose is 960 mg (4 tablets) twice daily.
Side effects of Vemurafenib
Common side effects include fatigue, nausea, arthralgias, rash, alopecia, photosensitivity, pruritus, and skin papilloma. Uncommon, but potentially severe side effects include severe skin and hypersensitivity reactions (including Stevens Johnson syndrome), cutaneous squamous cell carcinoma, ocular toxicity, and prolonged QTc intervals.