Nineteen adults with bile duct cancer carrying an NRG1 gene fusion were enough for the FDA to approve Bizengri for a new use. Of those patients, 37% responded to the drug, and the responses lasted anywhere from three months to 13 months.
Cholangiocarcinoma, the bile duct cancer in question, is rare and often aggressive. Bizengri is now the first medication approved specifically for adults whose tumors have the NRG1 (neuregulin 1) fusion and are metastatic or inoperable. The FDA granted the approval to Partner Therapeutics, Inc.
A fast review
The agency reviewed the application under the Commissioner’s National Priority Voucher pilot program, which is meant to speed therapies for rare conditions by cutting review times sharply. FDA Commissioner Dr. Marty Makary said patients with ultra-rare cancers badly need new options. The decision follows Bizengri’s 2024 clearance for certain lung and pancreatic cancers.
Patients with advanced bile duct cancer, according to the Cleveland Clinic, often have few effective choices once their first treatments stop working.
How it targets the tumor
An NRG1 fusion happens when two separate segments of a cell’s DNA join. That tells the cell to grow and multiply abnormally and eventually leads to tumors. Bizengri goes after this driver and is meant to interrupt the growth signal in patients whose cancer is fueled by it.
Safety
The serious risks include infusion-related reactions, left ventricular dysfunction, which affects the heart’s ability to pump, and lung conditions such as interstitial lung disease or pneumonitis. Patients more often report milder effects: fatigue, body aches, digestive problems and swelling (edema).
Finding eligible patients
NRG1-fusion cholangiocarcinoma is exceptionally rare, so patients may have to look for specialized oncology centers able to test for gene fusions. Because the drug came through an accelerated pilot program, access to this kind of precision medicine is often concentrated in high-tier research hospitals. Families should favor facilities that offer broad molecular profiling to confirm whether the tumor carries the NRG1 alteration.
