Basilea Pharmaceutica Ltd. announced that updated interim results from cohort 2 of the phase 2 study FIDES-01 (Fibroblast growth factor Inhibition with DErazantinib in Solid tumors) were presented at the American Society of Clinical Oncology (ASCO) Gastrointestinal (GI) Cancers Symposium 2022, held from January 20 to 22, in San Francisco, USA. Cohort 2 of FIDES-01 is assessing the safety and anti-tumor activity of Basilea's orally administered fibroblast growth factor receptor (FGFR) inhibitor, derazantinib, in patients with locally advanced or metastatic intrahepatic cholangiocarcinoma (iCCA), a form of bile duct cancer, harboring FGFR2 mutations or amplifications. At the cut-off date for the interim analysis, August 31, 2021, 28 patients had been dosed, of which 23 patients were eligible for the efficacy assessment with a median follow-up period of 5.2 months.

Based on investigator assessments, the disease control rate (DCR) was 74%, including two patients with a confirmed objective response and 15 patients with stable disease, where tumor shrinkage was observed in the majority of patients. The median progression-free survival (PFS) was 7.3 months. The DCR and median PFS are similar to those reported for the group of iCCA patients with FGFR2 fusions from cohort 1 of the FIDES-01 study.

The observed safety and tolerability was consistent with the profile reported for cohort 1, with low incidences of nail toxicities, stomatitis, hand-foot syndrome and retinal effects, which have been associated with the FGFR inhibitor class.