Partner Therapeutics has received the US Food and Drug Administration (FDA) approval for Bizengri (zenocutuzumab-zbco) to treat adults with advanced, unresectable or metastatic cholangiocarcinoma harbouring a neuregulin 1 (NRG1) gene fusion and who have progressed on or after prior systemic therapy.

The approval process was accelerated after Partner Therapeutics received the FDA Commissioner’s National Priority Voucher.

Bizengri has already received breakthrough therapy and orphan drug designations for this indication.

The US biotechnology company highlighted the clinical need in this patient population, with the new approval marking a regulatory milestone.

The FDA approval was based on data from the multi-centre, open-label, multi-cohort Phase II eNRGy clinical trial involving adults with advanced solid tumours hosting NRG1 gene fusions.

Out of 22 patients with unresectable or metastatic NRG1+ cholangiocarcinoma, 19 were evaluable for efficacy. The confirmed overall response rate was 36.8%, with duration of response ranging from 2.8 to 12.9 months.

Common adverse reactions (at or above 20%), excluding laboratory findings, included abdominal pain, diarrhoea, dyspnoea, musculoskeletal pain, nausea, and decreased appetite.

Bizengri previously gained accelerated approval in 2024 for use in non-small cell lung cancer and pancreatic adenocarcinoma in patients harbouring an NRG1 fusion after systemic therapy.

The drug is included in the National Comprehensive Cancer Network (NCCN) Clinical Practice Guidelines in Oncology for non-small cell lung cancer, pancreatic adenocarcinoma, and cholangiocarcinoma.

Partner Therapeutics chief development officer Pritesh Gandhi said: “The FDA approval of Bizengri for NRG1 fusion-positive cholangiocarcinoma is a historic milestone for patients who have had no approved targeted therapy. We thank the patients, their families, and the investigators for their participation in the eNRGy trial.

“The results demonstrate meaningful tumour responses, durable benefit, and a favourable tolerability profile—and we are grateful that the FDA’s Commissioner’s National Priority Voucher pilot programme greatly reduced the review time, helping bring this treatment to patients more quickly. We look forward to working with the oncology community to ensure appropriate patients can access Bizengri without delay.”