Updated exploratory results from the TOPAZ-1 Phase III trial showed AstraZeneca?s IMFINZI (durvalumab) in combination with standard-of-care chemotherapy demonstrated a clinically meaningful long-term overall survival (OS) benefit at three years for patients with advanced biliary tract cancer (BTC). These results from TOPAZ-1, which are the longest survival follow-up ever reported for a global, randomized Phase III trial in this setting, will be presented on April 18 at the 2024 Cholangiocarcinoma Foundation Conference in Salt Lake City, Utah. At more than three years (median follow-up of 41.3 months), results showed IMFINZI plus chemotherapy reduced the risk of death by 26% versus chemotherapy alone (based on a hazard ratio [HR] of 0.74; 95% confidence interval [CI], 0.63-0.87).

The median OS was 12.9 months for IMFINZIplus chemotherapy versus 11.3 months for chemotherapy alone. More than twice as many patients on the IMFINZI-based regimen were alive at three years versus chemotherapy alone (14.6% versus 6.9%). The TOPAZ-1 trial met the primary endpoint of OS in October 2021 at a planned interim analysis, showing that the combination reduced the risk of death by 20% versus chemotherapy alone (based on a HR of 0.80; 95% CI, 0.66-0.97; 2-sided p=0.021 at a statistical significance threshold of 0.03).

IMFINZI plus chemotherapy continued to be well-tolerated, with no new safety signals observed with longer follow-up. Results showed 15.4% of patients experienced treatment-related serious adverse events with IMFINZI plus chemotherapy versus 17.3% with chemotherapy alone.