ALX Oncology reports trial data for gastric cancer drug

ALX Oncology has released the results of its ASPEN-06 Phase 2 trial, which tested the investigational CD47-blocker evorpacept alongside other treatments in patients with advanced gastric or gastroesophageal cancer. The study, published in Nature Medicine, found that the combination of evorpacept with trastuzumab, ramucirumab and paclitaxel led to a 40.3% objective response rate, compared to 26.6% among patients receiving standard treatment.

For patients whose cancer still expressed HER2 protein, the response rate jumped to 48.9% versus 25.0% in the control group. Post-analysis revealed that CD47 expression on tumors could predict treatment success, with high CD47 levels associated with a 63.6% response rate compared to 23.1% in the control cohort. Median progression-free survival improved to 19.5 months, and median duration of response to the therapy extended to 25.5 months.

ALX Oncology CEO Barbara Klencke noted that the data showed patients with HER2-positive tumors and high CD47 expression benefited the most from evorpacept-based treatment. The company has decided against pursuing a U.S. Phase 3 trial for gastric cancer and will instead explore development partnerships for the program. ALX will concentrate on its ongoing Phase 2 ASPEN-09-Breast trial, which assesses evorpacept in HER2-positive metastatic breast cancer, with preliminary results from 80 patients expected in mid-2027.