Kinnate Biopharma Inc. announced that the U.S. Food and Drug Administration (FDA) has granted Fast Track designation for Kinnate's investigational pan-FGFR inhibitor, KIN-3248, for the treatment of patients with unresectable, locally advanced or metastatic cholangiocarcinoma (CCA) harboring fibroblast growth factor receptor 2 (FGFR2) gene fusions or other alterations, who have received at least one prior systemic therapy. Cholangiocarcinoma, also known as bile duct cancer, is a rare condition, often diagnosed when it is advanced. Research has shown that FGFR is an actionable alteration in patients with CCA.

FGFRs are tyrosine kinases that play a crucial role in cell proliferation, differentiation, migration and survival. FGFR2 gene fusions or other alterations are identified in approximately 16% of intrahepatic cholangiocarcinoma (ICC) tumors. Fast Track is a process designed by the FDA to facilitate the development and expedite the review of drugs to treat serious conditions and fulfill an unmet medical need.

A therapeutic candidate that receives Fast Track designation is eligible for more frequent interactions with the FDA to discuss the candidate's development plan, and if relevant criteria are met, for Accelerated Approval and Priority Review. About KIN-3248 KIN-3248 is an irreversible, small molecule pan-FGFR inhibitor designed to address primary FGFR2 and FGFR3 oncogenic alterations, including those predicted to drive acquired resistance to current FGFR-targeted therapies, such as gatekeeper, molecular brake, and activation loop mutations observed in cancers such as ICC and urothelial carcinoma (UC). In preclinical studies, KIN-3248 demonstrated inhibitory activity across a wide range of clinically relevant mutations that drive primary disease and acquired resistance to other FGFR inhibitors.

The KN-4802 clinical trial (NCT05242822) is an ongoing multi-center, open-label, two-part study of approximately 120 patients to evaluate the safety, tolerability, pharmacokinetics, and preliminary efficacy of KIN-3248 in adults with advanced tumors harboring FGFR2 and/or FGFR3 gene alterations. In dose escalation (Part A), the trial will determine the recommended dose and schedule of KIN-3248 for further evaluation in patients with FGFR2 and/or FGFR3 gene alteration-driven cancers. Dose expansion (Part B) will assess the safety and efficacy of KIN-3248 at the recommended dose and schedule in FGFR inhibitor naïve and FGFR inhibitor pretreated patients with cancers driven by FGFR2 and/or FGFR3 gene alterations, including ICC, UC, and other advanced or metastatic solid tumors in adults.

This trial is currently enrolling across multiple sites in the U.S. and Taiwan, with additional sites expected globally. Initial dose escalation data is anticipated in the second half of 2023. The company previously announced that a poster presentation of the design and rationale of the KN-4802 clinical trial will be presented at the upcoming American Society of Clinical Oncology (ASCO) Genitourinary Cancers Symposium.

Details are included below. ASCO Genitourinary Cancers Symposium, February 16-18, 2023 Title: First-in-Human Phase 1/1b Study Evaluating KIN-3248, a Next--Generation, Irreversible Pan-FGFR Inhibitor, in Patients With Advanced Urothelial Carcinoma and Other Solid Tumors Harboring FGFR2 and/or FGFR3 Gene Alterations Author: Benjamin Garmezy, MD Abstract Number: TPS593 Poster Board: P16 Session Type and Track: Trials in Progress Poster Session, Urothelial Carcinoma Session Date: February 17, 2023, 12:30 p.m. PT /3:30 p.m. ET.