Roche Tecentriq and Cotellic Combination Fails Ph III Trial in Colorectal Cancer

Roche announced on 5/10/18 that the Phase III IMblaze370 study evaluating the combination of Tecentriq (atezolizumab) and Cotellic (cobimetinib) did not meet its primary endpoint of overall survival (OS) compared to regorafenib. The study evaluated the combination in people with difficult-to-treat, locally advanced or metastatic colorectal cancer (CRC) whose disease progressed or who were intolerant to at least two systemic chemotherapy regimens.

More than 95% of patients in IMblaze370 have microsatellite stable (MSS) tumours and based on the available data, checkpoint inhibitors as monotherapy have not demonstrated clinically meaningful efficacy in MSS mCRC. The results from IMblaze370 were consistent with this prior monotherapy experience, showing that treatment with Tecentriq alone did not provide a meaningful clinical benefit compared to regorafenib in this patient population.

Roche's Tecentriq is already approved for use in some bladder cancer and lung cancer patients. Roche is running trials of the immunotherapy to treat other cancers. Colorectal cancer would have been a big market. There are approximately 180,000 new cases in the US each year.

Tecentriq suffered a setback in 2017 when a phase III trial failed to show that the drug increased survivial times in bladder cancer patients. It was feared that the failure would put the drug's conditional approval for bladder cancer in jeopardy. However, the company announced in September of 2017 that they expected the drug's accelerated approval status would be maintained.  

Shares of Exelixis (which owns Cotellic) were down 12% as of this writing.