Zymeworks Inc. has announced the approval of Zanidatamab by the National Medical Products Administration (NMPA) in China for the treatment of previously treated, unresectable, or metastatic HER2-positive (HER2+) biliary tract cancer (BTC). This conditional approval makes Zanidatamab the first and only dual HER2-targeted bispecific antibody approved for HER2-high expression (IHC3+) BTC in China.
The approval also triggers a $20 million milestone payment to be received from BeOne Medicines, with Zymeworks remaining eligible to receive up to $144 million in additional development and commercial milestones. Under the terms of its agreement with BeOne Medicines, Zymeworks has received $61 million in upfront and milestone payments, as well as certain co-development funding for Zanidatamab clinical studies. Zymeworks is also entitled to receive tiered royalties of up to 19.5% of net sales in BeOne Medicine’s territories.
Zanidatamab was previously approved by the U.S. Food and Drug Administration (FDA) in November 2024 for the treatment of adults with previously treated, unresectable, or metastatic HER2+ (IHC 3+) BTC. In addition, Jazz Pharmaceuticals, Zymeworks’ partner, announced in April 2025 that the European Medicines Agency (EMA) committee for Medicinal Products for Human Use (CHMP) adopted a positive opinion recommending the approval of Zanidatamab for the treatment of advanced HER2+ BTC.
Biliary tract cancers (BTC) account for approximately 3% of all digestive system tumors and are often associated with a poor prognosis. Approximately 11%-25.2% of patients with BTC are HER2-positive. The incidence rate of BTC is on the rise globally, particularly in Asian countries and regions.
Zanidatamab is a dual HER2-targeted bispecific antibody that simultaneously binds extracellular domains 2 and 4 on separate HER2 monomers, leading to internalization and resulting in tumor growth inhibition and tumor cell death. Zymeworks, as a global clinical-stage biotechnology company, is committed to the discovery, development, and commercialization of novel, multifunctional biotherapeutics.
The company’s mission is to make a meaningful difference in the lives of people impacted by difficult-to-treat conditions such as cancer, inflammation, and autoimmune disease. Zymeworks’ engineered and developed Zanidatamab using the company’s proprietary Azymetric™ technology.
Zymeworks is rapidly advancing a robust pipeline of wholly-owned product candidates, leveraging its expertise in both antibody-drug conjugates and multispecific antibody therapeutics targeting novel pathways in areas of significant unmet medical need. Phase 1 studies for other product candidates are actively recruiting, with an investigational new drug application for another planned for mid-2025. Zanidatamab is currently under regulatory review in the EU for second-line BTC and is being evaluated in multiple global clinical trials as a potential best-in-class treatment for patients with multiple HER2-expressing cancers. As a result of these announcements, the company's shares have moved 0.7% on the market, and are now trading at a price of $11.43. For the full picture, make sure to review Zymeworks's 8-K report.
