For patients with advanced head and neck cancers, immune-based therapies have started to show results against these hard-to-treat tumors. Two immunotherapy drugs were approved in 2016 for use when standard treatments failed, and many other agents are being tested in clinical trials.
Immunotherapies work by enhancing the body’s natural defenses against malignancies, and have made their largest impact so far in melanoma and lung cancer. Drugs known as checkpoint inhibitors, or blockers, make cancer cells more vulnerable to attack by the immune system’s killer T cells. Two such drugs, pembrolizumab (Keytruda) and nivolumab (Opdivo), were approved in 2016 for patients with advanced head and neck cancers that standard treatments failed to halt.
Dana-Farber researchers were involved in clinical trials showing that these drugs shrunk tumors in a significant number of such patients and lengthened their survival, according to Robert Haddad, MD, who leads the Head and Neck Cancer Treatment Center.
“We are now testing combinations of immunotherapy agents in various settings,” Haddad explains.
One clinical trial at Dana-Farber is comparing nivolumab to a combination of nivolumab and ipilimumab (Yervoy), another checkpoint blocker, as a first-line therapy in patients with treatment-resistant squamous cell carcinoma of the head and neck (SCCHN). Another trial is testing nivolumab plus ipilimumab versus chemotherapy as first-line therapy.
An experimental checkpoint inhibitor, lirilumab, aims at a different molecular target than pembrolizumab and nivolumab. Haddad says a combination of lirilumab and nivolumab is in clinical trials at Dana-Farber for patients with metastatic SCCHN. This is the most common form of head and neck cancer, accounting for three to five percent of all cancers in the United States.
Dana-Farber investigators are also testing the approach of administering immunotherapy prior to surgery, with the goal of decreasing the size of the cancer before removing it. This approach is showing “very promising early results” with single and combination immunotherapy drugs, according to Haddad.
The role of immunotherapy in head and neck cancer is in its earliest stages of evolution. Scores of clinical trials are in progress testing other checkpoint inhibitors and additional immunotherapy strategies, including vaccines and adoptive cellular therapy, to learn if they can benefit patients with SCCHN.