GlaxoSmithKline shoots for combo attack against melanoma in surgery patients

Melanoma under a microscope--Image courtesy of NIH

GlaxoSmithKline ($GSK) has stepped up its late-stage program to advance a combo of targeted cancer drugs against deadly skin cancer, with a new study to see whether its experimental BRAF and MEK inhibitors can keep melanoma from coming back after surgeries.

The London-based drug giant said that the late-stage "COMBI-AD" study tests its BRAF blocker dabrafenib and MEK inhibitor trametinib in patients whose BRAF V600E mutation-positive melanoma has been surgically removed. The placebo-controlled trial is testing how long the combo treatment can delay or prevent cancer recurrence in these high-risk patients.

The trial comes as GSK races with Roche/Genentech to advance combination therapies against melanoma. Glaxo has two other late-stage trials in melanoma for the combo of its BRAF and MEK blockers, both of which were filed for U.S. approval last year as individual treatments for melanoma. Genentech, the U.S. biotech unit of Roche ($RHHBY), is doing late-stage testing of a rival dual therapy consisting of the experimental MEK inhibitor GDC-0973 from its partner Exelixis ($EXEL) and its approved BRAF inhibitor Zelboraf.

Glaxo takes the rivalry a step further with its late-stage trial for patients after surgeries.

"The patients included in this trial are at high risk of their melanoma returning after surgery and there are currently few treatment options to reduce this risk," said Dr. Rafael Amado, GSK's head of oncology R&D, in a statement. "Given the efficacy and safety findings observed with combined dabrafenib-trametinib treatment in the metastatic setting, we are investigating whether the combination administered after surgery can help these patients live longer without melanoma recurrence."

Less than half of patients on BRAF inhibitors develop another kind of skin cancer called cutaneous squamous cell carcinoma. In an earlier study, Glaxo showed that those tumors cropped up in 7% of patients on dabrafenib-trametinib and 19% of patients on dabrafenib, according to results reported last year in the New England Journal of Medicine. And patients on the combo lived 9.4 months without their cancer worsening compared with 5.8 months in the dabrafenib-only group.

- here is GSK's release