Three drug majors join forces to trial combo regimen for colorectal cancer

Following encouraging results from a Phase Ib study in Japan, Bayer (BAYN: DE), Bristol-Myers Squibb (NYSE: BMY) and Ono Pharmaceutical (TYO: 4525) are collaborating on a clinical trial evaluating the combination of the German firm’s kinase inhibitor Stivarga (regorafenib) and anti-PD-1 immune checkpoint inhibitor Opdivo (nivolumab) from B-MS and Ono, in patients with microsatellite-stable metastatic colorectal cancer (MSS mCRC), the most common type of CRC.

Regorafenib as monotherapy has demonstrated an overall survival benefit versus placebo in the pivotal Phase III CORRECT study and has shown activity irrespective of micro-satellite status in a retrospective analysis from this study, though with limited responses observed. Despite progress in the treatment of CRC, including the advance of effective immuno-oncology (I-O) treatments for certain subsets of CRC, around 95% of mCRC patients have MSS tumors, for which I-O monotherapy treatment approaches have shown limited activity.

Thus, the need for additional treatment options including combination approaches remains high. Encouraging early data have been seen with the combination of regorafenib and nivolumab. In a Phase Ib investigator sponsored trial from Japan called REGONIVO (NCT03406871, EPOC1603), the combination of regorafenib and nivolumab has shown promising preliminary efficacy results. The detailed data of the study were presented at the 2019 American Society of Clinical Oncology (ASCO) Annual Meeting.