Tecentriq and Cotellic combination fails Phase III trial to treat microsatellite-stable colorectal cancer

Tecentriq and Cotellic combination failed to improve survival over standard third-line therapy for patients with chemorefractory metastatic colorectal cancer (CRC) and microsatellite-stable disease, according to a phase III trial published in The Lancet Oncology.

Median overall survival with the PD-L1 inhibitor atezolizumab (Tecentriq) plus MEK inhibitor cobimetinib (Cotellic) was no better than treatment with regorafenib (Stivarga) for these patients (8.9 vs 8.5 months; HR 1.00, 95% Cl 0.73-1.38, P=0.99), reported Fortunato Ciardiello, MD, PhD, of Università degli Studi della Campania Luigi Vanvitelli in Naples, Italy, and colleagues. With a median overall survival of 7.1 months, atezolizumab alone was numerically worse than regorafenib (HR 1.19, 95% Cl 0.83-1.71, P=0.34), the researchers wrote in the journal. Median progression-free survival was 1.9 months in each of the atezolizumab arms versus 2.0 months in the regorafenib arm, and objective responses occurred in 3% of patients treated with atezolizumab-cobimetinib and in 2% of patients treated with each of the single agents.