Zymeworks Announces Positive Topline Data in the Pivotal HERIZON-BTC-01 Trial of Zanidatamab
- Zanidatamab as monotherapy produced a confirmed objective response rate (cORR) of 41.3% and median duration of response of 12.9 months in patients with previously treated HER2-amplified and expressing biliary tract cancers (BTC)
- Pending receipt of regulatory approvals, zanidatamab has the potential to be the first HER2-targeted therapy for patients with BTC
Zymeworksto host conference call today at 8:00 am Eastern Time(ET)
The positive topline results showed that 41.3% (95% CI: 30.4, 52.8) of enrolled patients with HER2-amplified and expressing (IHC2+ and 3+) disease achieved an objective response as assessed by independent central review. The median duration of response was 12.9 months (95% CI: 5.95 to not reached). The safety profile of zanidatamab in this trial was consistent with that observed in previously reported monotherapy studies, with no new safety signals identified. Full results from the pivotal trial are expected to be presented at a medical meeting in 2023.
Biliary tract cancers, including gallbladder cancer and cholangiocarcinoma, are diagnosed in more than 210,000 people every year1, with most patients presenting with inoperable disease2. Disease control with front-line therapy is modest and patients need treatment options after progression3,4. The human epidermal growth factor receptor 2 (HER2) is a promising target in approximately 5%-10% of cholangiocarcinomas and up to 20% of gallbladder cancers5. Currently no HER2-targeted therapy has been approved for the treatment of BTC.
“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
“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
Conference Call for Investors and Analysts
HERIZON-BTC-01 is a global, multicenter, open-label, single-arm study (NCT04466891) with a primary endpoint of confirmed objective response rate (cORR) by independent central review (ICR) per the Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST 1.1). Secondary endpoints include duration of response (DOR), proportion of subjects with a DOR ≥16 weeks, disease control rate (DCR), progression-free survival (PFS), overall survival (OS) and safety. HER2 amplification, as determined centrally by in situ hybridization (ISH) in tumor tissue, was an inclusion criterion for all subjects enrolled into the two study cohorts: Cohort 1, the primary efficacy cohort, with tumor tissue showing HER2 immunohistochemistry (IHC) 2+ or 3+ staining, and Cohort 2 with tumor tissue showing HER2 IHC 0 or 1+ staining. The study was initiated in
Zanidatamab is an investigational, bispecific antibody, based on Zymeworks’ Azymetric™ platform, that can simultaneously bind two non-overlapping epitopes of HER2, known as biparatopic binding. This unique design results in multiple mechanisms of action including dual HER2 signal blockade, increased binding and removal of HER2 protein from the cell surface, and potent effector function leading to encouraging antitumor activity in patients.
Cautionary Note Regarding Forward-Looking Statements
This press release includes “forward-looking statements” or information within the meaning of the applicable securities legislation, including Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. Forward-looking statements in this press release include, but are not limited to, statements that relate to the potential of zanidatamab in advanced HER2-expressing cancers with high unmet need; the potential therapeutic effects of zanidatamab and Zymeworks’ other product candidates; Zymeworks’ clinical development of its product candidates and enrollment in its clinical trials; anticipated clinical data presentations, including the expected presentation of full results from HERIZON-BTC-01 in 2023; expectations regarding future regulatory filings and approvals and the timing thereof; the commercial potential of technology platforms and product candidates including zanidatamab; the potential addressable market of zanidatamab; and other information that is not historical information. When used herein, words such as “plan”, “believe”, “expect”, “may”, “anticipate”, “potential”, “pending”, “will”, “would”, and similar expressions are intended to identify forward-looking statements. In addition, any statements or information that refer to expectations, beliefs, plans, projections, objectives, performance or other characterizations of future events or circumstances, including any underlying assumptions, are forward-looking. All forward-looking statements are based upon Zymeworks’ current expectations and various assumptions.
1 Siegel RLet al., Cancer statistics, 2020. CA Cancer J Clin. 2020;70:7-30
2 Schroff RT et al., Adjuvant Therapy for Resected Biliary Tract Cancer: ASCO Clinical Practice Guideline. Clin. Oncol.2019;37:1015-1027
3 Khankhel ZS et al., Second-line treatments in advanced biliary tract cancer: systematic literature review of efficacy, effectiveness and safety Future Oncol. 2022;18:18, 2321–2338
4 Lamarca A, et al., Second-line chemotherapy in advanced biliary cancer: a systematic review. Ann. Oncol. 2014;25:12, 2328–2338
5 Vogel A et al., on behalf of on behalf of the ESMO Guidelines Committee. Biliary tract cancer: ESMO Clinical Practice Guideline for diagnosis, treatment and follow-up, 2022. Ann Oncol doi: https://doi.org/10.1016/j.annonc.2022.10.506