FDA Approves Zenocutuzumab-zbco (Bizengri) for NRG1 Fusion-Positive Cholangiocarcinoma
FDA approved zenocutuzumab-zbco (Bizengri) for NRG1 fusion-positive cholangiocarcinoma on May 8, 2026. The eNRGy trial showed a 36.8% ORR. It also received priority review, breakthrough, and orphan designations.
On May 8, 2026, the U.S. Food and Drug Administration (FDA) approved zenocutuzumab-zbco (Bizengri), Partner Therapeutics, Inc., for adults with advanced, unresectable or metastatic cholangiocarcinoma harboring a neuregulin 1 (NRG1) gene fusion whose disease progressed on or after prior systemic therapy. NRG1 fusion-positive cholangiocarcinoma is an extremely rare, life-threatening malignancy, and the approval addresses an ultra-rare molecular subset with limited options.
The application was reviewed through the FDA Commissioner’s National Priority Review Voucher pilot program, which is intended to speed the review of therapies that may address important national health priorities. The FDA approved the application more than five months ahead of its goal date. Zenocutuzumab-zbco also received previously breakthrough therapy designation, orphan drug designation and priority review from the FDA.
The safety and efficacy of Bizengri were evaluated in eNRGy (NCT02912949), a multicenter, open-label, multi-cohort clinical trial in adults with advanced solid tumors. A total of 22 patients with unresectable or metastatic NRG1 fusion-positive cholangiocarcinoma were enrolled, with 19 evaluable for efficacy. The major efficacy outcome measures were confirmed overall response rate (ORR) and duration of response (DOR) as determined by a blinded independent central review according to RECIST v1.1. The ORR was 36.8% (95% CI: 16.3, 61.6), and the DOR ranged from 2.8 to 12.9 months.
The prescribing information includes warnings and precautions for infusion-related reactions, hypersensitivity reactions, anaphylactic reactions, interstitial lung disease (ILD)/pneumonitis, left ventricular dysfunction, and embryo-fetal toxicity. The most common adverse reactions reported with zenocutuzumab-zbco include diarrhea, musculoskeletal pain, fatigue, nausea, infusion-related reactions, dyspnea, rash, constipation, vomiting, abdominal pain, and edema. The recommended dose is 750 mg as an intravenous infusion every two weeks until disease progression or unacceptable toxicity.