ALX Oncology to Present Updated Data from Phase 2 ASPEN-06 Trial, Highlighting CD47 Expression as a Predictive Biomarker in HER2+ Gastric Cancer, at 40th Society for Immunotherapy of Cancer (SITC) Annual Meeting

SOUTH SAN FRANCISCO, Calif., Oct. 03, 2025 (GLOBE NEWSWIRE) -- ALX Oncology Holdings Inc., (“ALX Oncology” or “the Company”) (Nasdaq: ALXO), a clinical-stage biotechnology company advancing a pipeline of novel therapies designed to treat cancer and extend patients’ lives, today announced updated data from its Phase 2 ASPEN-06(NCT05002127)trial will be presented during a poster session at the Society for Immunotherapy of Cancer (SITC) 40th Annual Meeting taking place November 5–9, 2025, in National Harbor, Maryland. The Phase 2 trial evaluated evorpacept, the Company’s lead therapeutic candidate, in combination with HERCEPTIN®(trastuzumab), CYRAMZA®(ramucirumab) and paclitaxel, for patients with previously treated HER2-positive advanced gastric cancer (GC) and gastroesophageal junction (GEJ) cancer.

Details for the poster presentation at SITC 2025 are as follows:Title:CD47 expression as a predictive biomarker for evorpacept in HER2-positive gastric/gastroesophageal cancer from the Phase 2 randomized ASPEN-06 trialFirst Author:Zev A. Wainberg, M.D., Professor of Medicine and Co-Director of GI Oncology Program, University of California, Los AngelesAbstract:496Date and Time:Saturday, November 8, 2025, 10:00 a.m. – 6:35 p.m. ETLocation:Poster Hall (Exhibit Halls AB)

ASPEN-06 is a randomized Phase 2 (open-label)/3 (blinded), international, multi-center study, evaluating evorpacept in combination with HERCEPTIN®(trastuzumab), CYRAMZA®(ramucirumab) and paclitaxel, for patients with metastatic second- or third-line HER2 overexpressing gastric/GEJ adenocarcinoma that has progressed on or after prior HER2-directed therapy and fluoropyrimidine- or platinum-containing chemotherapy and are suitable for chemotherapy. One hundred twenty-seven adult patients were enrolled in the Phase 2 portion of the study.

ALX Oncology (Nasdaq: ALXO) is a clinical-stage biotechnology company advancing a pipeline of novel therapies designed to treat cancer and extend patients’ lives. ALX Oncology’s lead therapeutic candidate, evorpacept, has demonstrated potential to serve as a cornerstone therapy upon which the future of immuno-oncology can be built. Evorpacept is currently being evaluated across multiple ongoing clinical trials in a wide range of cancer indications. ALX Oncology’s second pipeline candidate, ALX2004, is a novel EGFR-targeted antibody-drug conjugate with a differentiated mechanism of action and entered the clinic in a Phase 1 trial in August 2025. More information is available atwww.alxoncology.comand on LinkedIn @ALX Oncology.

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