Zymeworks Inc. (NASDAQ: ZYME), a clinical-stage biotechnology company developing multifunctional biotherapeutics, today announced positive topline results from the pivotal Phase 2b HERIZON-BTC-01 open-label, single-arm clinical trial investigating zanidatamab, a HER2-targeted bispecific antibody, as monotherapy in patients with previously treated HER2-amplified and expressing BTC.
The favorable topline results revealed that 41.3% (95% CI: 30.4, 52.8) of recruited patients with HER2-amplified and expressing (IHC2+ and 3+) illness obtained an objective response as judged by independent central review. The median response time was 12.9 months (95% confidence interval: 5.95 to not reached). The safety profile of zanidatamab in this study was similar to prior monotherapy trials, with no new safety flags found. Full results from the pivotal study are scheduled to be presented at a medical symposium in 2023.
Every year, more than 210,000 people are diagnosed with biliary tract malignancies, including gallbladder cancer and cholangiocarcinoma, with the majority of patients having an incurable illness. Front-line therapy has limited disease control, and patients require therapeutic choices following progression. The human epidermal growth factor receptor 2 (HER2) is a prospective target in roughly 5%-10% of cholangiocarcinomas and up to 20% of gallbladder malignancies. The treatment of BTC does not yet have any HER2-targeted therapies licensed.
“Through our work with the BTC patient community, we see first-hand the challenge these patients face in not only getting a diagnosis but in the limited treatment options available,” said Stacie Lindsey, Founder & CEO of the Cholangiocarcinoma Foundation. “Each investigative trial begins to close the gap on this high unmet medical need by helping to bring more treatment options to BTC patients and we’re looking forward to watching zanidatamab’s progression through the global regulatory review process.”
“We are thrilled to report these positive topline data from the HERIZON-BTC-01 clinical trial, which further support the potential of zanidatamab as a new chemotherapy-free therapeutic option for HER2-amplified and expressing BTC. These data demonstrate that zanidatamab , as a single agent, improves on the current standard of care for patients in a difficult-to-treat disease who currently have a poor prognosis based on the limited treatment options currently available,” said Neil Josephson, M.D., Chief Medical Officer at Zymeworks. “I want to thank all of the patients, their families, and the investigators who participated in this important study.”
Source – Zymeworks
