A new study published in the February 22, 2012 issue of the New England Journal of Medicine shows that the drug ZelborafTM can reduce or eliminate tumors, delay disease progression, and extend life significantly for patients with inoperable or advanced metastatic (spreading) melanoma. Approved last year by The US Food and Drug Administration (FDA), Zelboraf (a.k.a. vemurafenib) nearly doubled patients’ life expectancy in the new study – from an average survival of only 6 to 10 months for untreated patients or those previously treated with other therapies, to an average survival of 16 months for those on Zelboraf.
Zelboraf is the first “targeted” therapy approved for melanoma; it targets the V600E BRAF gene, which is found to be mutated in approximately half of all patients with melanoma, causing uncontrolled (cancerous) cell growth. Zelboraf blocks the function of the defective BRAF gene, thereby slowing or stopping the uncontrolled cell growth. The drug was approved by the FDA’s priority review program, which “fast tracks” reviews of drugs that may provide significant treatment advances.
In the earliest published clinical trial, Zelboraf was successful in shrinking the tumors of 81 percent of patients who had the gene defect (or mutation), the greatest response rate a melanoma drug has ever had. In a subsequent trial, melanoma patients with the mutated gene who received Zelboraf were 56 percent less likely to die in the study period than those who received standard chemotherapy. They were also 74 percent less likely to see their disease advance compared with patients on chemotherapy.
ZelborafTM is taken orally, and the prescribed dose is 960 mg twice a day. The drug is marketed by Roche’s Genentech division.