Publication Wednesday, June 09, 2021 CCTG CO26: A cost-utility analysis of combined durvalumab and tremelimumab in patients with refractory metastatic colorectal cancer (mCRC) and high plasma tumour mutation burden (pTMB): A Canadian Cancer Trials Group (CCTG) study ASCO 2021 Publication: https://meetinglibrary.asco.org/record/198613/abstract Background: The randomized phase II CCTG CO.26 clinical trial investigated the use of combined durvalumab and tremelimumab vs. best supportive care (BSC) for patients with mCRC and suggested an increase in overall survival (OS). The largest benefit was seen in patients who were microsatellite stable (MSS) with a pTMB ≥ 28 variants per megabase. Considering significantly higher adverse event rates and costs associated with durvalumab and tremelimumab, it is important to evaluate its cost-effectiveness. Accordingly, we performed a cost-utility analysis of durvalumab and tremelimumab compared to BSC in the intention-to-treat (ITT) and biomarker-enriched populations using CO.26 trial data. Conclusions: Combined durvalumab and tremelimumab is not considered cost-effective in refractory mCRC under conventional willingness-to-pay thresholds. Cost-effectiveness is improved with biomarker enrichment for high pTMB, driven by the greater derived health outcomes in this subgroup.
