Bristol-Myers Squibb (BMS) and Daiichi Sankyo have entered a collaborative clinical trial to evaluate the combination of BMS’ immunotherapy Opdivo (nivolumab) and Daiichi Sankyo’s investigational antibody drug conjugate DS-8201 in HER2-expressing metastatic breast and urothelial (bladder) cancers.

“We are excited to evaluate if the combination of these two mechanisms of action—the ability of an anti-PD-1 to harness the immune system and the potential of DS-8201 to deliver chemotherapy directly to target cancer cells—may be able to improve the outcomes of patients with HER2-expressing advanced breast and bladder cancer,” said Antoine Yver, executive vice president and global head, oncology research and development, Daiichi Sankyo. “Pursuing combination studies like this is at the core of the Daiichi Sankyo Cancer Enterprise strategy, as we are looking to maximize the potential of our proprietary antibody drug conjugate technology to help address the unmet needs of patients living with cancer.”

Fouad Namouni, head of development, oncology, BMS, said, “Combination therapy with agents that target different and complementary pathways—in this case, the combination of a checkpoint inhibitor and innovative chemotherapy delivery—is a potential new approach for patients with difficult to treat cancers. We are looking forward to working with Daiichi Sankyo to investigate the synergies of these treatment methods.”

The Phase 1b multicenter, open-label study will include two parts. The dose escalation part will determine a possible recommended dose of DS-8201 in combination with Opdivo in patients with HER2-expressing breast cancer who are refractory to standard therapies or for which no standard therapy is available. The dose expansion part of the study will evaluate the efficacy, safety and tolerability of combining Opdivo with DS-8201 at the established dose level in patients with HER2-expressing advanced/metastatic breast cancer as well as HER2-expressing urothelial (bladder) cancer in patients previously treated with chemotherapy.

The study is expected to begin enrollment in first quarter of 2018 in the U.S. and Europe. Daiichi Sankyo will be the sponsor conducting the trial.