Durvalumab plus chemotherapy for advanced biliary tract cancer: post hoc analysis of the phase 3 TOPAZ-1 trial

The primary analysis of the multinational (105 centers in 17 countries) phase 3 TOPAZ-1 trial showed that durvalumab plus gemcitabine and cisplatin (GemCis) resulted in significant overall survival (OS) advantage versus placebo plus GemCis with comparable safety between treatment groups in participants with advanced biliary tract cancer (aBTC). Post hoc analysis of TOPAZ-1, evaluating 4-year OS and safety, has now been published. Patients received intravenous durvalumab 1500 mg (n=341) or placebo (n=344) plus GemCis on days 1 and 8 every 3 weeks for up to 8 cycles, followed by durvalumab or placebo monotherapy every 4 weeks. Median follow-up was 56.9 months for the durvalumab group and 50.7 months for the placebo group. Median OS was 13.0 months for the durvalumab group and 11.4 months for the placebo group (HR 0.75; 95% CI 0.64-0.88); 48-months OS rate was 11.8% versus 4.3%, respectively. The rate of serious adverse events possibly related to treatment was similar between arms (15.4% versus 17.3%), whereas the rate of discontinuation due to adverse events was 6.2% versus 5.3%. The authors conclude that this post hoc analysis showed that among patients with aBTC, addition of durvalumab to GemCis resulted in long-term survival benefit with a manageable safety profile (visual abstract).