GSK races to regulators for approvals of new skin cancer drugs
In what has already been a speedy clinical program, GlaxoSmithKline ($GSK) has sprinted to regulators in the U.S. and European Union with applications for approvals of two targeted drugs for treating melanoma. And the drug giant's quick work with the experimental drugs shows how fast a company can get to a new drug application with treatments for well-defined groups of patients and impressive clinical data.
London-based GSK wowed the industry at the ASCO meeting in June with results from Phase III trials for the two drugs, dabrafenib and trametinib. Dabrafenib, which targets BRAF mutations, beat chemotherapy in the late-stage BREAK3 study, in which patients on the drug lived for 5.1 months without their cancer worsening compared with 2.7 months for those on chemo. In the company's METRIC study, patients on trametinib, a MEK mutation inhibitor, had 4.8 months of progression-free survival, three times the PFS as patients on chemo.
As planned, GSK is seeking approvals of the drugs as single agents against the deadly skin cancer first, amid efforts to show the benefits of using the pair of treatments in combination for melanoma in late-stage studies. In the U.S., the drugmaker is seeking the FDA's approval for both dabrafenib and trametinib for patients with BRAF V600 mutations that have been tested for the cancer-related genetic abnormality. Its partner bioMérieux has already asked for U.S. approval of a companion diagnostic. Glaxo is initially seeking EU approval only for dabrafenib for that population of patients, with plans to turn in an application for trametinib in the coming months.
In June, GSK's oncology chief Paolo Paoletti told FierceBiotech that the company had reported Phase III results on the pair of melanoma drugs roughly three years after hitting the clinic for early-stage trials. That sort of speed in a clinical program is what many oufits in the pharma industry are trying to match, and the FDA has shown a willingness to give quick OKs to treatments that show evidence of impressive efficacy in extremely sick patients. At the same time, the cancer drug game has grown crowded with competitors chasing after the same hot oncology targets.
Glaxo plans to show in a late-stage study that its combination of dabrafenib and trametinib offers benefits over Roche's ($RHHBY) approved BRAF inhibitor Zelboraf. There's already early evidence that GSK's combo addresses cases of non-melanoma skin tumors that form in patients who take BRAF inhibitors. Repeating those results in late-stage studies could give GSK an edge in the market for melanoma drugs.