Hoosier Cancer Research Network investigators presented a poster highlighting GI17-319, a gastric and esophageal adenocarcinoma study, during the AACR Annual Meeting 2021.

A single arm, multi-center phase 2 trial of mFolfox6 + trastuzumab + avelumab in first-line, metastatic, HER2-amplified gastric and esophageal adenocarcinomas, GI17-319 examined whether adding the anti-PD-L1 antibody avelumab to the chemotherapy drug trastuzumab and FOLFOX chemotherapy would result in a greater response rate than expected with trastuzumab and FOLFOX alone in HER2-amplified gastroesophageal cancer.

Researchers concluded the combination of avelumab, trastuzumab, and FOLFOX chemotherapy demonstrated evidence of activity, and response rate and median progression-free survival compared favorably to results expected with trastuzumab plus chemotherapy from historical data. These outcomes corroborate with results from prior small studies of chemotherapy, trastuzumab, and immune checkpoint inhibitors in patients with HER2-amplified metastatic gastroesophageal adenocarcinoma and demonstrate the potential for the addition of immune checkpoint inhibitors in this setting.

“Prior studies of chemotherapy and immunotherapy combinations in gastric and esophageal cancers focused on HER2-negative tumors, in whom it was recently found that the combination is indeed more effective than chemotherapy alone,” said lead author Michael S. Lee, MD (pictured), of the University of Texas MD Anderson Cancer Center. “However, whether this applies to the 20-30% of gastric and esophageal cancer patients whose tumors are HER2-positive has not been known. In these patients with HER2-positive cancers, the current standard of care is chemotherapy combined with the targeted anti-HER2 therapy trastuzumab. This HCRN study combined this standard treatment of chemotherapy and trastuzumab with immunotherapy, with very promising results.”

Co-author Pashtoon M. Kasi, MD, of the University of Iowa Holden Comprehensive Cancer Center, said results of this and other studies have already prompted larger phase 3 studies looking at anti-HER2 and immunotherapy combinations. “We look forward to the results of these larger studies and anticipate this could become an option for our patients given the promising recurring results across different trials,” he said.

Correlative studies from tumor specimens and peripheral blood including analyses on circulating tumor DNA collected on study are in progress.

Study authors include: Michael S. Lee, Joseph Chao, Mary F. Mulcahy, Pashtoon M. Kasi, Angela T. Alistar, Sarbajit Mukherjee, Mehmet Akce, Dominic T. Moore, Cheryl A. Carlson, and Autumn J. McRee.

Participating institutions included Atlantic Health System, City of Hope, Robert H. Lurie Comprehensive Cancer Center of Northwestern University, Roswell Park Cancer Institute, University of Iowa Holden Comprehensive Cancer Center, University of North Carolina Lineberger Comprehensive Cancer Center, and Winship Cancer Institute of Emory University.

A total of 18 subjects were enrolled in the study.

See abstract.

About Hoosier Cancer Research Network:

Hoosier Cancer Research Network (formerly known as Hoosier Oncology Group) conducts innovative cancer research in collaboration with academic and community physicians and scientists across the United States. The organization provides comprehensive clinical trial management and support, from conception through publication. Created in 1984 as a program of the Walther Cancer Institute, Hoosier Cancer Research Network became an independent nonprofit clinical research organization in 2007. Since its founding, Hoosier Cancer Research Network has conducted more than 230 trials in a variety of cancer types and supportive care, resulting in more than 350 publications. More than 9,000 subjects have participated in Hoosier Cancer Research Network clinical trials.