Checkpoint Inhibitor Deals: Searching For IO Combinations To Unlock Cancer’s Black Box

Immunotherapy treatments for cancer, and the potential synergistic effects of combining established PD-1/PD-L1 checkpoint inhibitors with other experimental candidates and mechanisms, will continue to drive oncology deal-making in 2020. As of November 2019, there were 2,251 active PD-1/PD-L1 combination therapy trials testing 295 different targets, according to the Cancer Research Institute, a non-profit that supports research and development of immunotherapy treatments for cancer. Clinical successes, however, have slowed from the heady days of the early and mid-2000s, when it seemed as though checkpoint inhibitors might become the cancer cures patients and pharmaceutical companies hoped would beat back the disease once and for all.

Almost 10 years have passed since the initial FDA approval of Bristol-Myers Squibb Co.’s cancer drug Yervoy (ipilipumab), an...