Zelboraf(vemurafenib) is anti BRAF kinase inhibitor. ZELBORAF™ is indicated for the treatment of patients with unresectable or metastatic melanoma with BRAFV600E mutation as detected by an FDA-approved test.
More than 30 mutations of the BRAF gene associated with human cancers have been identified. However, most of them work thorugh pathways and in a similar way to the BRAF-E. With this in mind, other BRAF mutations than E should also respond to Zelboraf. In the Chapman study, on which the FDA approval was based, there were ten patients with BRAF-K mutation and they showed some response. Ten patients in the vemurafenib group were later found to have BRAF V600K mutations; of these patients, 4 had a partial response (40%). Being that there are so many different BRAF mutations, it is not reasonable to require large studies performed for each mutation subtype.
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