Dr. Uboha on Early Efficacy Data With Zanidatamab in HER2+ Upper GI Cancers

Nataliya V. Uboha, MD, PhD, assistant professor, Department of Medicine, University of Wisconsin School of Medicine and Public Health, discusses early efficacy data demonstrated with zanidatamab in HER2-expressing upper gastrointestinal (GI) cancers.

Zanidatamab is a biparatopic antibody that binds to the trastuzumab (Herceptin)-targeted and pertuzumab (Perjeta)-targeted domains of HER2, Uboha says.

During the 2021 Gastrointestinal Cancers Symposium, findings from the 3-part, phase 1 ZW25-101 trial (NCT02892123) demonstrated promising antitumor activity with zanidatamab in patients with HER2-expressing gastroesophageal adenocarcinoma that has progressed following previous therapies, including HER2-directed therapies.

As a single agent, zanidatamab elicited an overall response rate (ORR) of 33%. In combination with chemotherapy, the ORR was 54%. The median progression-free survival was 3.6 months with zanidatamab monotherapy and 5.6 months with zanidatamab plus chemotherapy.

Although the results are preliminary and only 33 patients were evaluable for response, the efficacy signals demonstrated with zanidatamab in this patient population warrants further study in larger clinical trials, concludes Uboha.