The rush to find combinations of PD-1 inhibitors and established cancer therapies marks the end of the beginning, rather than the beginning of the end, of the search for ways to extend use of checkpoint inhibitors to the two-thirds of patients who are non-responders. The new thinking is that emerging targets in the tumor microenvironment can either turbo-boost PD-1 or re-arm the immune response, but researchers will need a streamlined strategy to select the right targets to match in different tumors.
The concept of targeting the tumor microenvironment is moving fast from the lab to the boardroom. Two weeks ago, Surface Oncology Inc. announced a $35 million series A round led by the company's seed investor, Atlas Venture. The newco was set up late last year to find immune processes beyond PD-1 that can be targeted in cancer.