Zymeworks Doses First Patient In Phase I Trial Of ZW25, A Novel Bi-Specific Antibody For The Treatment Of HER2-Expressing Cancers

VANCOUVER, British Columbia--(BUSINESS WIRE)--Zymeworks Inc., a biopharmaceutical company discovering and developing innovative multi-functional protein-based therapeutics, including bi-specific antibodies and drug conjugates for the treatment of cancer, announced today that the first patient was dosed in a Phase 1 clinical trial of ZW25 for treatment of HER2-expressing tumors.

“No approved HER2-targeted therapies exist for many patients with HER2-expressing cancers and with its unique mechanism of action, ZW25 has the potential to address this significant unmet need.”

As Zymeworks’ lead therapeutics program, ZW25 is a novel bi-specific antibody developed using the Company’s Azymetric™ platform. The compound targets two different epitopes (bi-paratopic targeting) of the human epidermal growth factor receptor 2 (HER2) protein, which is over-expressed on the surface of many tumor types, including certain breast, gastric, lung, and ovarian cancers.

“We are excited to have begun enrollment in this initial study of ZW25,” said Diana Hausman, M.D., Zymeworks’ Chief Medical Officer. “No approved HER2-targeted therapies exist for many patients with HER2-expressing cancers and with its unique mechanism of action, ZW25 has the potential to address this significant unmet need.”

ZW25 is being evaluated in the clinic for safety, as well as efficacy, in patients with tumors with low to moderate levels of HER2 expression. ZW25 is active in numerous in vivo models of HER2 low to high expressing cancers, including ovarian cancer, for which it has received Orphan Drug Designation from the FDA. ZW25 has demonstrated an acceptable safety profile in preclinical toxicology studies when administered at multiple dose levels using a once per week dosing schedule.

About ZW25
ZW25 is Zymeworks’ lead therapeutics program based on the Azymetric™ platform. It is an engineered bi-specific antibody that targets two different epitopes (bi-paratopic targeting) of the HER2 protein and confers its efficacy via multiple mechanisms of action, including: (i) enhanced antibody-mediated effector function resulting from the increased decoration of the tumor cell surface; (ii) increased blockade of the HER2 cellular growth signal by the dual engagement of HER2 epitopes; and (iii) increased removal of surface-expressed HER2 protein due to enhanced HER2 internalization upon antibody engagement. ZW25 is a best-in-class HER2-targeting antibody for a variety of tumors characterized by HER2 overexpression, including breast, gastric, ovarian, colorectal and non-small cell lung cancers. The FDA has granted Orphan Drug Designation to ZW25 for the treatment of ovarian cancer.

About Zymeworks Inc.
Zymeworks is a privately held clinical-stage biotherapeutics company that is developing best-in-class Azymetric™ bi-specific antibodies and antibody drug conjugates for the treatment of cancer, autoimmune and inflammatory diseases. The company’s novel Azymetric™, AlbuCORE™, and EFECT™ platforms, its Zymelink™ conjugation platform and cytotoxins, and its proprietary ZymeCAD™ structure-guided protein engineering technology, enable the development of highly potent bi-specific antibodies, multivalent protein therapeutics, and antibody drug conjugates across a range of indications. Zymeworks is focused on accelerating its biotherapeutics pipeline through in-house research and development programs and strategic collaborations. More information on Zymeworks can be found at www.zymeworks.com.