New immunotherapy approaches put the pedal to the metal

March 25, 2016

Two promising immunotherapies – anti-PD-1 and anti-OX40 – aim to take the brakes off the immune system and rev up its cancer-fighting power. Providence Cancer Center is integrating these and other promising immunotherapy approaches into conventional treatment for patients with head and neck cancers.

Providence Cancer Center researchers have initiated several important clinical trials to investigate the effectiveness of promising new immunotherapies to treat patients with head and neck cancers. “Using the body’s own immune system as a defense against cancer has been our center’s goal for over 20 years,” says Walter Urba, M.D., Ph.D., director of research at Providence Cancer Center. “I am pleased at the prospect of offering these potentially life-saving trials to patients at our center.”

Anti-PD-1: Helping the immune system recognize tumors

One of the most promising immunotherapies currently being tested in patients with head and neck cancers is a monoclonal antibody called anti-PD-1. This treatment aims not to kill cancer cells directly, but to enhance the immune system’s ability to recognize tumor cells so it can go after them.

The treatment pathway involves two proteins that protect tumor cells from immune system recognition: programmed death-1 (PD-1), which is expressed on the surface of T cells, and programmed death ligand-1 (PD-L1), which is expressed on cancer cells. Together, PD-1 and PD-L1 effectively shield tumor cells from being recognized, putting the “brakes” on the immune system. In trials with other cancers, anti-PD-1 has shown promise for blocking this interaction, effectively releasing the brakes so the T cells can identify and destroy cancer cells.

Anti-OX40: Revving up the immune system to attack cancer

Providence Cancer Center enrolled the first patient in the world in a phase I clinical trial investigating the safety and preliminary clinical activity of an anti-OX40 agonist (MEDI0562) in patients with recurrent or metastatic squamous cell carcinoma of the head and neck. Rom Leidner, M.D., presented data from the ongoing study at the American Society of Clinical Oncology Annual meeting in 2015.

Anti-OX40 is a monoclonal antibody that appears to rev up the body’s immune response to cancer. The agonist binds to and activates OX40, a protein on the surface of T cells that has the ability to amplify their power to attack cancer cells. Several anti-OX40 clinical trials are ongoing at Providence Cancer Center, building on more than 15 years of pioneering translational research led by Providence researchers Andrew Weinberg, Ph.D., and Brendan Curti, M.D.

Both anti-OX40 and anti-PD-1 are currently available to patients at Providence Cancer Center in both the preoperative and metastatic setting.