HER2 is overexpressed in approximately 20% of GEA patients. For these patients, Herceptin® (trastuzumab) is the only approved HER2-targeted therapy in 1L treatment, and therapeutic options are currently limited if disease progression occurs. Zanidatamabs bispecific approach
simultaneously binds two non-overlapping epitopes of HER2, ECD2 and ECD4, resulting in multiple mechanisms of action that provide potential therapeutic benefits beyond the combination of two monoclonal
Herceptin and chemotherapy have been the standard of care in first-line HER2-positive GEA for over 10 years. The data presented today
give us the confidence that we have developed a next-generation HER2-targeted agent that has the potential to provide patients with an improved option in this setting, said Neil Josephson, M.D., Zymeworks Interim Chief Medical Officer.
Based on these data, we will pursue a randomized, Phase 3 trial with the aim of establishing zanidatamab as the foundational agent of a new standard of care in first-line HER2-positive GEA.
In addition to the Phase 2 study presented today, Zymeworks and its partner, BeiGene, Ltd., are conducting a parallel open-label Phase 2 clinical trial
evaluating zanidatamab and chemotherapy in combination with the PD-1 inhibitor, tislelizumab, in first-line HER2-positive metastatic GEA. These results are expected to be presented at a future medical
Zymeworks plans to launch, with BeiGene, a randomized, global Phase 3 study
(HERIZON-GEA-01) in Q4 2021. The study will evaluate zanidatamab plus chemotherapy (CAPOX or FP) with or without tislelizumab, versus standard of care (trastuzumab plus
chemotherapy), for first-line treatment of locally advanced, unresectable, or metastatic HER2-positive GEA.
Our long-standing vision for zanidatamab has been for it to become a
best-in-class HER2-targeted therapeutic that could address the needs of a broad spectrum of patients with HER2-expressing cancers, said Ali Tehrani, Ph.D., Zymeworks President & CEO. Over the years we have shared data that have showcased the promising anti-tumor activity and safety profile of
zanidatamab; that said, the data shared today stand out as they represent the first clinical validation of zanidatamab in a front-line setting. As we embark on our second pivotal trial and prepare for commercialization, these data represent a
landmark moment for zanidatamab and for Zymeworks.
Dr. Ku has provided advisory services for Zymeworks.
The presentation will be available to
conference registrants on the ESMO conference website as well as to the general public on the Zymeworks website at
(Ph) 2 Study of Zanidatamab + Chemotherapy (chemo) in First Line (1L)
Gastroesophageal Adenocarcinoma (GEA)
Lead Author: Geoffrey Ku, M.D., Memorial Sloan Kettering Cancer Center, New York, NY, US