Overview
- Topline Phase 3 HERIZON‑GEA‑01 results showed Ziihera plus chemotherapy improved progression‑free survival versus trastuzumab plus chemotherapy, while the addition of Tevimbra delivered a statistically significant overall survival benefit.
- The Ziihera plus chemotherapy arm showed a clinically meaningful overall survival effect with a strong trend toward significance, with another OS interim analysis planned for mid‑2026.
- Benefits were observed across PD‑L1 subgroups, with higher objective response rate and duration of response for both Ziihera regimens, and no new safety signals reported in the topline release.
- Jazz plans a full data presentation in Q1 2026, peer‑review publication, and submission for rapid inclusion in NCCN guidelines, followed by an sBLA filing in the first half of 2026.
- Following the readout, Zymeworks adopted a partnership‑focused strategy centered on milestones and royalties, pointing to up to about $440 million in potential near‑term payments as shares rallied alongside Jazz.