Zanidatamab Injection (ZIIHERA) Approved in China for HER2-Positive Advanced Biliary Tract Cancer
May 29, 2025 — The National Medical Products Administration (NMPA) has granted conditional approval through a priority review pathway for Zanidatamab Injection (brand name: ZIIHERA), developed by BeiGene (Suzhou) Biologics Co., Ltd.
👉 The medication is indicated for patients with unresectable locally advanced or metastatic HER2-high (IHC3+) biliary tract cancer who have previously received systemic therapy, providing a new targeted therapy option for a population with limited treatment choices.
Notably, the drug received accelerated approval from the U.S. FDA six months earlier, reflecting its potential in global HER2-positive biliary cancer treatment.
Biliary Tract Cancer Overview and Clinical Challenges
Biliary tract cancer, including gallbladder cancer and cholangiocarcinoma, accounts for approximately 3% of all digestive tract malignancies.
😔 But it is highly aggressive and often asymptomatic in early stages, earning it the nickname “little king of cancer.”
Most patients are diagnosed at a locally advanced or metastatic stage, making surgical options limited:
- Only about 10% of patients are candidates for surgery at diagnosis; however, recurrence or metastasis within one year post-surgery reaches 67%, and the 5-year survival rate is only 5%-15%.
- For patients ineligible for surgery, conventional chemotherapy or radiotherapy offers limited efficacy, with median overall survival under one year.
- Approximately 11%-25.2% of biliary tract cancer patients are HER2-positive, with higher mortality and postoperative recurrence compared to HER2-negative patients, highlighting an urgent need for effective targeted therapies.
Innovative Mechanism of Zanidatamab Injection
Zanidatamab injection is a bispecific antibody that differentiates itself from traditional monoclonal antibodies by simultaneously binding two distinct epitopes of HER2 (ECD2 and ECD4):
- 🔬 Dual-target inhibition: Blocks tumor signaling at two critical sites, preventing cancer cell proliferation.
- 💉 Immune activation: Recruits immune cells to attack and eliminate cancer cells, achieving both direct anti-tumor and immune-mediated effects.
In other words, if HER2 is considered the “broadcast tower” sending tumor growth signals, Zanidatamab acts like a dual-handed sentinel.
✨ It can shut down signal initiation and transmission while calling in the immune system to assist—effectively achieving broader and more potent HER2 blockade.
Key Clinical Data: HERIZON-BTC-01 Study
🌐 The global pivotal Phase IIb HERIZON-BTC-01 trial included 62 patients with HER2-high (IHC3+) unresectable or metastatic biliary tract cancer who had previously received systemic therapy:
- Efficacy: Objective response rate (ORR) was 52%, with a median duration of response (DOR) of 14.9 months, median progression-free survival (PFS) of 7.2 months, and median overall survival (OS) of 18.1 months.
- fatigue. Safety: 53% of patients experienced serious adverse events, most commonly diarrhea, infusion-related reactions, abdominal pain, and fatigue. Other severe events included biliary obstruction, biliary infection, sepsis, pneumonia, and gastrointestinal complications.
💪 These results demonstrate that Zanidatamab significantly prolongs survival and maintains disease control in HER2-positive patients compared with historical data showing median OS under one year.
Significance of Approval and Impact on Clinical Practice
The approval of Zanidatamab in China represents a major advance for patients, physicians, and the oncology community:
- New treatment options for patients: HER2-positive BTC patients, previously with limited therapies, now have access to a precision-targeted therapy capable of improving survival and quality of life.
- Promotion of precision medicine: The approval encourages routine HER2 testing, enabling more patients to benefit from targeted therapies.
- Expanding research and treatment opportunities: Ongoing studies are exploring Zanidatamab in combination with chemotherapy and immunotherapy as a potential first-line therapy, as well as its efficacy in other HER2-positive cancers, including breast, gastric, and lung cancers.
🔬 The 2024 Chinese Expert Consensus on HER2 Molecular Diagnosis and Clinical Application in Biliary Malignancies recommends HER2 testing for all patients with locally advanced or metastatic BTC to identify candidates for anti-HER2 therapy.
Future Outlook
The launch of Zanidatamab in China signifies a new era in the treatment of HER2-positive biliary tract cancer, offering hope for patients who previously had few effective options.
🧑⚕️ With ongoing clinical trials, further research is exploring its potential in combination therapies, earlier lines of treatment, and other HER2-positive tumor types, which could transform the global therapeutic landscape.
With the approval of Zanidatamab, this innovative therapy not only offers new hope for patients with HER2-positive biliary tract cancer but also creates opportunities for pharmaceutical service providers.
💁♂️ DengYue Medicine will continue to monitor advancements in this field and is committed to providing patients and healthcare professionals with up-to-date drug information and support services.
I believe you will find this article interesting 🔻 if you are particularly interested in the development of innovative drugs.
