The FDA has approved Zenocutuzumab (Bizengri) for adults with advanced bile duct cancer linked to rare $NRG1$ gene fusions after previous treatments stopped working. The approval gives a new option to patients with this ultra-rare form of cholangiocarcinoma, a cancer that usually has very limited treatment choices.
The decision was based on results from the phase 1/2 eNRGy trial, which included 19 patients with $NRG1$ fusion–positive cholangiocarcinoma. About 37% of patients responded to the treatment, and responses lasted between 2.8 and 12.9 months. Patients received 750 mg of the drug through intravenous infusion every two weeks.
Zenocutuzumab is a bispecific antibody designed to target both HER2 and HER3 proteins, helping block cancer growth signals. The National Comprehensive Cancer Network recently added the drug to its treatment guidelines for $NRG1$ fusion–positive cholangiocarcinoma.
Common side effects included diarrhea, nausea, vomiting, fatigue, rash, swelling, and infusion-related reactions. More serious risks included interstitial lung disease, pneumonitis, and heart-related problems such as left ventricular dysfunction.
The FDA used its national priority voucher pilot program to speed up the review because of the major unmet need in this rare cancer population.