Real-World Outcomes of Ivosidenib in IDH1-Mutant Biliary Tract Cancer: A Multicenter Retrospective Analysis and...

Ivosidenib is established as targeted therapy in patients with isocitrate dehydrogenase 1 (IDH1)-mutant advanced biliary tract cancer based on results of the phase III ClarIDHy trial. However, data on the efficacy of ivosidenib in real-world cohorts are limited.

This retrospective analysis aims to provide data on the efficacy and safety of ivosidenib in biliary tract cancer in a real-world cohort.

Patients with IDH1 mutant biliary tract cancer treated with ivosidenib at four German university medical centers from 2020 to 2024 were retrospectively identified. Clinicopathological parameters and treatment courses were collected. Furthermore, clinical outcomes of patients with biliary tract cancer who received ivosidenib were retrospectively retrieved from the global health network database TriNetX.

In total, 14 patients who received ivosidenib were identified. Mean age at diagnosis was 61 years and 50% of patients were female. Nine patients had an IDH1 R132C, four an IHD1 R132L, and one an IDH1 R132S mutation. Ten patients received ivosidenib as second-line therapy and four in later lines. Partial response was observed in two patients, stable disease in three, and progressive disease in nine patients. Median progression-free survival was 5.6 months (95% confidence interval 4.3, not estimated) and median overall survival was 12.7 months (95% confidence interval 8.2, not estimated). No discontinuation of ivosidenib because of toxicity was observed. A total of 228 patients were identified in the TriNetX database. Mean age was 64.4 years and 64% of patients were female. Median overall survival in this cohort was 9.6 months (95% confidence interval 8.07, 11.19).

Real-world data from our cohort and the TriNetX database support the oncological outcomes reported in the ClarIDHy trial and other real-world cohorts.