Results of the HERIZON-BTC-01 Trial of Zanidatamab in Biliary Tract Cancers With Shubham Pant, MD
At the recent American Society of Clinical Oncology (ASCO) Annual Meeting, Dr. Shubham Pant, Associate Professor in the Department of Medical Oncology at MD Anderson Cancer Center, presented the results of HERIZON-BTC-01, a phase 2b trial investigating zanidatamab in previously treated human epidermal growth factor receptor 2 (HER2)–amplified biliary tract cancers. Afterwards he spoke with Oncology Data Advisor to share more about the efficacy, safety, and future directions for zanidatamab.
Oncology Data Advisor: Welcome to Oncology Data Advisor. Today, we're here at the ASCO Annual Meeting, and I'm joined by Dr. Pant. Thank you so much for joining.
Shubham Pant, MD: Thank you.
Oncology Data Advisor: I'm interested to hear more about the results of the HERIZON-BTC-01 trial that you are presenting. Would you like to give us an overview and some background about this trial?
Dr. Pant: Yes, so this was a global phase 2b trial done in HER2-positive patients with biliary tract cancers. It's a rare patient population, but HER2 is a very valid target in this patient population. We had 80 patients who were tumor immunohistochemistry (IHC) 2+ or 3+. They were high expressors, and we saw some really good response rates in these patients.
Oncology Data Advisor: What is the progression-free survival (PFS) data from the trial that you're presenting here?
Dr. Pant: This data is for Cohort 1, which was all in situ hybridization (ISH)–positive patients. All of these patients were amplified; they were IHC 2+ or 3+. The overall response rate was 41%, and the duration of response was 12.9 months. Our progression-free survival was 5.5 months.
Oncology Data Advisor: Were there any notable toxicities associated with zanidatamab?
Dr. Pant: The main toxicities that we saw were diarrhea and infusion-related reactions. Most were grade 1 and 2, and they were easily manageable.
Oncology Data Advisor: As the trial progresses, how do you foresee zanidatamab fitting into the treatment landscape?
Dr. Pant: I think this is a really exciting time for biliary tract cancers in general. In the second-line setting, post-event, when people progress after first-line therapy, I think this could be a very valid targeted therapy for these HER2-overamplified patients.
Oncology Data Advisor: Are there any other future directions for the trial or investigations in other settings?
Dr. Pant: I think this trial is done, but the future directions are, can we think about combining it with other therapies—chemotherapy, immunotherapy—or move forward with zanidatamab as a single agent because we saw such good activity?
Oncology Data Advisor: Awesome. That's really exciting. Thanks so much for talking to me about this.
Dr. Pant: Thank you.
About Dr. Pant
Shubham Pant, MD, is an Associate Professor in the Department of Gastrointestinal Medical Oncology and the Department of Investigational Cancer Therapeutics at the University of Texas, MD Anderson Cancer Center. His research focuses on early drug development of targeted therapies and immunotherapies in gastrointestinal cancers, including pancreatic, biliary, gallbladder, and colorectal cancers. Dr. Pant has presented or coauthored more than 100 abstracts at international meetings and is an author on the ASCO Metastatic Pancreatic Cancer Guidelines.
For More Information
Pant S, Fan J, Oh DY, et al (2023). Results from the pivotal phase (Ph) 2b HERIZON-BTC-01 study: zanidatamab in previously-treated HER2‑amplified biliary tract cancer (BTC). J Clin Oncol, 41(suppl_16). Abstract 4008. DOI:10.1200/JCO.2023.41.16_suppl.4008
Transcript edited for clarity. Any views expressed above are the speaker's own and do not necessarily reflect those of Oncology Data Advisor.