AstraZeneca’s tremelimumab, to be branded as Imjudo, was approved by the US. FDA in combination with Imfinzi (durvalumab) for the treatment of unresectable liver cancer in adults.
The drug is a CTLA-4 inhibitor that works by targeting the protein of the same name, which has been implicated with T-cell activation, setting up the immune response to cancer and supporting cancer cell death. CTLA-4 drugs work similarly to PDL1s, and in this case, Imjudo is approved for use in combination with AstraZeneca's Imfinzi, a PDL-1 monoclonal antibody that was first approved in 2017.
The recent approval hinged on results from the HIMALAYA phase 3 trial, in which patients treated with the combination experienced a 22% death risk reduction. The study was published in the New England Journal of Medicine Evidence and assessed the combo’s efficacy in comparison to Bayer’s Nexavar, a kinase inhibitor drug approved for hepatocellular carcinoma (HCC) treatment. Data showed that roughly 31% of patients treated with Imjudo and Imfinzi were still alive after three years and only 20% of patients treated with sorafenib were still alive during follow-up.
The combo regimen is called the STRIDE (single tremelimumab regular interval durvalumab) regimen and is given as a single 300 mg dose of Imjudo and 1,500 mg Imfinzi, followed up by additional Imfinzi doses every four weeks.
The nod comes as long-awaited validation for AstraZeneca after years of betting on the investigational drug, even using a priority review voucher to reduce FDA review time. Other regulatory applications for the combination treatment are being reviewed internationally in Europe, Japan, and other countries for the treatment of patients with advanced disease, which accounts for more than half of liver cancer cases.
