Orphan Drugs: GlaxoSmithKline’s Combo Melanoma Treatment
GlaxoSmithKline (GSK) receives FDA approval in May 2013, for two orphan drugs for the treatment of patients with advanced or unresectable melanoma :
Both drugs are approved as single agents, not as a combination treatment. Tafinlar, a BRAF inhibitor, is approved for melanoma whose tumors express the BRAF V600E gene mutation. Mekinist, a MEK inhibitor, is approved for melanoma whose tumors express the BRAF V600E or V600K gene mutations. Both drugs are approved with a companion genetic test, ThxID BRAF test, made by France’s bioMérieux, which will help determine if a patient’s melanoma cells have the V600E or V600K mutation in the BRAF gene. About 50% of Melanomas arising in the skin have a BRAF gene mutation.
GSK announces on January 8, that the FDA gives the first combination oral targeted therapy, Tafinlar + Mekinist, accelerated approval for the treatment of unresectable or metastatic melanoma, with BRAF V600E or V600K mutations. These mutations must be detected by an FDA-approved test. Melanoma is diagnosed worldwide in approximately 160,000 people per year. It spreads quickly to internal organs and the average survival is 6 – 9 months.
The approval of Tafinlar + Mekinist :
• Is based on a Phase I/II study demonstrating response rate & median duration of response
• Disease-related symptoms or overall survival has not yet been shown
• Is through FDA’s Accelerated Approval program & reviewed under a Priority Review designation (given in September 2013)
• Accelerated approval is contingent on a Phase III trial (Combi-D).
Trametinib was in-licensed by GSK in 2006. It holds the worldwide exclusive rights to develop and commercialize Mekinist, with the exception of Japan where Japan Tobacco retains co-promotion rights.
Please Note: “Petri Dish” courtesy of Linda Bartlett (Photographer). National Institute Of Health [Public domain] | Wikimedia Commons.