On 20 November 2024, the US Food and Drug Administration (FDA) granted accelerated approval to zanidatamab-hrii (Ziihera, Jazz Pharmaceuticals, Inc.), a bispecific HER2-directed antibody, for previously treated, unresectable or metastatic HER2-positive (IHC 3+) biliary tract cancer (BTC), as detected by an FDA-approved test.
On same date, the FDA also approved VENTANA PATHWAY anti-HER-2/neu (4B5) Rabbit Monoclonal Primary Antibody (Ventana Medical Systems, Inc./Roche Diagnostics) as a companion diagnostic device to aid in identifying patients with BTC who may be eligible for treatment with Ziihera.
Efficacy was evaluated in HERIZON-BTC-01 (NCT04466891), an open-label multicentre, single-arm study in 62 patients with unresectable or metastatic HER2-positive (IHC3+) BTC. Patients were required to have received at least one prior gemcitabine-containing regimen in the advanced disease setting.
The major efficacy outcome measures were objective response rate (ORR) and duration of response (DoR) as determined by an independent central review according to RECIST v1.1. ORR was 52% (95% confidence interval [CI] 39, 65) and median DoR was 14.9 months (95% CI 7.4, not estimable).
The prescribing information contains a boxed warning for embryo-foetal toxicity. The most common adverse reactions reported in at least 20% of patients who received zanidatamab-hrii were diarrhoea, infusion-related reactions, abdominal pain, and fatigue.
The recommended zanidatamab-hrii dose is 20 mg/kg administered as an intravenous infusion once every 2 weeks until progression or unacceptable toxicity.
This review used the Assessment Aid, a voluntary submission from the applicant to facilitate the FDA’s assessment.
This application was granted priority review, breakthrough therapy designation, and orphan drug designation.
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For assistance with single-patient INDs for investigational oncology products, healthcare professionals may contact FDA’s Oncology Center of Excellence Project Facilitate.