FDA Speeds Testing of Two Therapies for Ovarian Cancer Targeting HER2

FDA Speeds Testing of Two Therapies for Ovarian Cancer Targeting HER2

Zymeworks announced that the U.S. Food and Drug Administration (FDA) has granted its lead investigational products, ZW25 and ZW33, orphan drug designation as potential treatments for ovarian cancer (OC).

The company’s lead therapeutic program, ZW25, is an investigational, bi-specific antibody, developed using the company’s Azymetric platform, that targets two different epitopes of the human epidermal growth factor receptor 2 (HER2) protein, which is over-expressed on the surface of several tumor types, including in ovarian, breast and lung cancers.

ZW25 mechanisms of action, according to a press release, include:

  • Enhanced effector function mediated by antibodies
  • Increased blockade of the HER2 cellular growth signal
  • Increased removal of HER2 protein expressed on a tumor’s surface

ZW25 is set to start its Phase 1 clinical development in late August in the United States. ZW33 is a drug conjugation of ZW25 currently in development, and being prepared for an investigational new drug (IND) application early in 2017.

“We are very excited with the potential of our novel engineered bispecific antibody ZW25 and its drug conjugate ZW33, as new treatment options for patients with ovarian cancer,” Gordon Ng, PhD, Zymeworks’ chief scientific officer, said in the release. “We believe ZW25’s and ZW33’s multiple differentiated mechanisms of action can be significantly more efficacious than current HER2-directed treatments for HER2 expressing cancers and can enhance the range of current treatments available to these patients.”

Orphan drug status qualifies Zymeworks for certain development incentives, including tax credits for clinical testing and market exclusivity for seven years if the compounds receive approval for this indication.

More than 22,000 women in the U.S. are diagnosed with ovarian cancer every year. There are currently no HER2-targeted treatments approved for this disease.

“We’re pleased that the FDA has recognized the significant need for new and better therapies for women with ovarian cancer, which remains the leading cause of death due to gynecological malignancies,” said Diana Hausman, Zymeworks’ chief medical officer. “The granted orphan drug designations underscore the potential of both ZW25 and ZW33 in addressing this important unmet medical need. We are looking forward to initiating clinical development for this indication in the very near future.”