MHRA approves zanidatamab for biliary tract cancer

The MHRA has approved zanidatamab (Ziihera) for adults with advanced biliary tract cancer that is HER2-high and has progressed after prior treatment; a single-arm study in 80 patients reported tumour shrinkage or no detectable disease in about 52% of the 62 HER2-high participants.

MHRA has approved zanidatamab (Ziihera) for use in adults with biliary tract cancer that shows high levels of the HER2 protein and has progressed after previous treatment. The approval applies when the cancer cannot be removed by surgery and has spread locally or to other parts of the body. The MHRA said it will continue to monitor the medicine's safety and effectiveness as it is used more widely. Key facts: - The MHRA announced approval on 19 February 2026 for zanidatamab in adults with HER2-high biliary tract cancer after prior treatment. - The licence covers unresectable locally advanced or metastatic disease. - A single-arm study of 80 patients reported that about 52% of the 62 HER2-high participants had tumour shrinkage or no detectable disease after an average follow-up of 34 months; the study did not include a comparison group. - Zanidatamab is administered by intravenous infusion every two weeks; full side-effect and restriction details are provided in the package leaflet. Summary: The MHRA's decision makes zanidatamab available for adults with advanced HER2-high biliary tract cancer that has progressed after prior treatment. The approval follows a single-arm study reporting responses in around half of HER2-high patients. The regulator said it will monitor safety and effectiveness as use expands. Undetermined at this time.