Cobimetinib + Zelboraf (vemurafenib) coBRIM Phase III study follow up - Genentech + Roche

Genentech, a member of the Roche Group announced follow-up data from two studies of the investigational MEK inhibitor cobimetinib in combination with Zelboraf (vemurafenib). Updated data from the pivotal coBRIM Phase III study showed the combination helped people with previously untreated BRAF V600 mutation-positive advanced melanoma live a median of one year (12.3 months) without their disease worsening or death (progression-free survival; PFS) compared to 7.2 months with Zelboraf alone (hazard ratio [HR]=0.58, 95 percent confidence interval [CI] 0.46-0.72).

The updated results from coBRIM also demonstrated higher response rates with cobimetinib and Zelboraf compared to Zelboraf alone. The objective response rate (ORR) with the combination was 70 percent (16 percent complete response [CR], 54 percent partial response [PR]) compared to 50 percent (11 percent CR, 40 percent PR) in the Zelboraf arm. With further follow-up, the complete response rate increased from 10 percent to 16 percent with the combination as some patients who had a partial response achieved a complete response after more than one year of treatment. The safety profile of cobimetinib and Zelboraf was consistent with safety data previously reported.

Follow-up data from the Phase Ib BRIM7 study showed cobimetinib plus Zelboraf helped people who had not been previously treated with a BRAF inhibitor live a median of more than two years (28.5 months). In addition, extended follow-up showed 61 percent of patients who had not been previously treated with a BRAF inhibitor were alive after two years. The safety profile was consistent with the previous analyses.

Comment;The FDA has accepted and granted Priority Review for the company’s New Drug Application (NDA) for cobimetinib in combination with Zelboraf (vemurafenib) for the treatment of people with BRAF V600 mutation-positive advanced melanoma. The FDA will make a decision on approval by August 11, 2015. The combination was filed at the EU in September 2014.