Zymeworks Partner Jazz Pharmaceuticals to Present Ziihera Clinical Trial Data at AACR Annual Meeting

Zymeworks announced that the company's partner, Jazz Pharmaceuticals, will present four abstracts featuring data from clinical trials evaluating Ziihera at the American Association for Cancer Research Annual Meeting, being held April 17-22, 2026 in San Diego, CA. "We are pleased to see the continued clinical progress of zanidatamab reflected in multiple presentations at AACR," said Ken Galbraith, Chair, CEO. "These studies highlight emerging data evaluating zanidatamab across tumor types beyond biliary tract cancer and gastroesophageal adenocarcinoma, and contribute to the growing body of evidence supporting its potential across HER2-expressing cancers." Highlights at the AACR Annual Meeting include: An oral presentation with results from the Phase 2 single-arm, open-label NeoZanHER trial evaluating zanidatamab for the investigational use as neoadjuvant monotherapy in patients with early-stage HER2+ breast cancer. At six weeks, zanidatamab treatment resulted in a statistically significant decrease in tumor size and volume from baseline, and 30% of patients achieved pathologic complete response. Treatment with zanidatamab was manageable with no new safety signals. A poster presentation detailing mechanistic and multi-omics analyses characterizing zanidatamab's differentiated HER2 biology, including dual, domain-specific binding and downstream effects on key cellular signaling pathways, with insights into activity in models following progression on trastuzumab deruxtecan. Additional presentations further explore zanidatamab's utility across HER2-expressing solid tumors and within innovative biomarker-driven clinical trial designs, including adaptive organ-preservation strategies in gastroesophageal adenocarcinoma.