The U.S. Food and Drug Administration (FDA) has approved a combination of two immuno-oncology drugs for the treatment of unresectable liver cancer. The combination of the anti-CTLA agent tremelimumab (Imjudo) and the anti-PD-L1 agent durvalumab (Imfinzi) is being closely watched to see if it could be a new hope for liver cancer treatment.

The approval was based on the HIMALAYA phase 3 trial. The HIMALAYA trial made headlines because it proposed a different dosing schedule than traditional immuno-oncology combinations.  This dosing regimen, also known as the STRIDE regimen, is a single dose of tremelimumab followed by durvalumab at regular intervals (single tremelimumab, regular-interval durvalumab). Patients with liver cancer who received immuno-oncology drugs in the STRIDE regimen did well compared to the control group who received sorafenib.

The Himalaya study enrolled a total of 1,171 patients with liver cancer, who were assigned to the STRIDE regimen, durvalumab alone, and sorafenib. The median overall survival for patients receiving the STRIDE regimen was 16.43 months, compared to 13.77 months in the sorafenib arm. The three-year survival rate was also different (30.7% vs. 20.2%), which statistically translates to an approximately 22% reduction in the risk of death for patients receiving the STRIDE regimen. Dervalumab monotherapy also proved to be as effective as sorafenib in controlling disease: the rate of moderate adverse events was highest in the sorafenib arm (52.4%) and lowest in the dervalumab monotherapy arm (37.1%).

Advanced liver cancer is known to be a cancer with a poor prognosis due to the limited number of anti-cancer drugs available. Given the efficacy and adverse event data from the Himalaya trial, immuno-oncology combinations or monotherapy are expected to become a new treatment option for patients with advanced liver cancer.