Imfinzi holds its own in bile duct cancer

AstraZeneca’s narrow lead over Merck & Co in bile duct cancer might widen slightly. Chemo combos of Imfinzi and Keytruda are both approved for first-line use here, but Astra has just revealed updated overall survival numbers from its registrational Topaz-1 trial, and these suggest that the data are improving: with median 41.3 months’ follow-up Imfinzi plus chemo is showing a reduction in risk of death of 26% versus chemo alone, which is better than the 20% in Topaz-1’s earlier cut stated on the Astra drug’s label. The median OS benefit has also widened slightly – from the earlier 1.3 months to 1.6 months now. The latest data from Keytruda’s registrational Keynote-966 trial show a 1.8-month mOS benefit, but with a worse hazard ratio of 0.83. Moreover, the numerical PFS benefit in Keynote-966 wasn’t statistically significant, and there was no remission rate benefit at all in the Merck trial, which also saw a greater rate of severe adverse events overall and a numerically higher rate of treatment-related deaths than Topaz-1. On a cross-trial basis Imfinzi thus remains the treatment of choice, though ultimately bile duct cancer is a niche setting overall.

The battle in 1st-line bile duct cancer

Note: *not statistically significant. Source: AstraZeneca statement & OncologyPipeline.