Exhibit 99.1
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Zymeworks Receives Orphan Drug Designation from the European Commission for HER2-Targeted Bispecific Antibody Zanidatamab in Patients with Gastric Cancer
Vancouver, British Columbia (November 19, 2020) – Zymeworks Inc. (NYSE: ZYME), a clinical-stage biopharmaceutical company developing multifunctional biotherapeutics, today announced that the European Commission (EC) has granted Orphan Drug designation for zanidatamab, the company’s investigational HER2-targeted bispecific antibody, in patients with gastric cancer.
“We are encouraged by the European Commission’s and European Medicines Agency’s recognition of the benefit that zanidatamab can provide in the treatment of HER2-expressing gastric cancers as we continue to expand our clinical development globally,” said Diana Hausman, M.D., Chief Medical Officer at Zymeworks.
The EC grants Orphan Drug designation to therapies that represent a significant benefit over existing treatments, are intended for the treatment, prevention or diagnosis of a life-threatening or chronically debilitating disease, and where prevalence of the condition in the European Union (EU) is less than 5 in 10,000 persons. Orphan drug designation gives companies certain benefits, including 10 years of market exclusivity following regulatory approval, reduced regulatory fees, clinical protocol assistance, and access to research grants.
“While gastric cancer is a rare disease, European countries experience the highest incidence rates among all Western countries” said James Priour, Senior Vice President, Commercial, at Zymeworks. “The European Commission’s granting of Orphan Drug designation for zanidatamab represents an important step towards bringing this promising investigational medicine to patients in Europe and around the world.”
Zymeworks previously received Orphan Drug designations for zanidatamab in gastric, biliary tract and ovarian cancers from the US FDA, as well as two Fast Track designations from the FDA for zanidatamab.
About Zanidatamab
Zanidatamab is a bispecific antibody, based on Zymeworks’ Azymetric™ platform, that can simultaneously bind two non-overlapping epitopes of HER2, known as biparatopic binding. This unique design results in multiple mechanisms of action including dual HER2 signal blockade, increased binding, and removal of HER2 protein from the cell surface, and potent effector function leading to encouraging antitumor activity in patients. Zymeworks is developing zanidatamab in multiple Phase 1, Phase 2, and registration-enabling clinical trials globally as a targeted treatment option for patients with solid tumors that express HER2. The US FDA has granted two Fast Track designations to zanidatamab, one as a single agent for refractory BTC and one in combination with standard of care chemotherapy, for first-line Gastroesophageal Adenocarcinoma (GEA). Zanidatamab has also received Orphan Drug designations for the treatment of biliary tract, gastric and ovarian cancers from the US FDA, in addition to Orphan Drug designation for the treatment of gastric cancer from the European Medicines Agency.