Wednesday, May 21, 2025 Effects of cannabinoids on immune checkpoint inhibitor response: CCTG pooled analysis Immune checkpoint inhibitors (ICI) have become an important treatment option for cancer patients and has been associated with improved survival outcomes across various tumor types. Cannabinoids are active components of cannabis and include tetrahydrocannabinol (THC) and cannabidiol (CBD). Cannabis use has increased in Canadian cancer patients and is often used for symptom management. Some studies have suggested that cannabinoids can alter the function of the immune system, which could impact the effectiveness of immune checkpoint inhibitors. Therefore, we aimed to evaluate whether cannabinoid use might impact the effectiveness of combination ICI treatment with durvalumab plus tremelimumab (with/without chemotherapy) using data from four clinical trials completed through the Canadian Cancer Trials Group (CCTG). We found no significant difference in response, survival outcomes or adverse events in patients who used cannabinoids with combination ICI treatment compared to cannabinoid non-users. This study supports the safe use of cannabinoids in the context of combination ICI therapy. Coschi CH, Ding K, Tong J, Tu D, O’Callaghan C, Leighl NB, Vera-Badillo F, Juergens RA, Hao D, Seymour L, Renouf DJ, Chen E, Gaudreau P-O, Fung AS. Effects of cannabinoids on immune checkpoint inhibitor response: CCTG pooled analysis of individual patient data. Immunotherapy 17: 257-268. 2025. https://doi.org/10.1080/1750743X.2025.2485012
