A China-based Phase II trial recorded a pathological complete response in 34 of 67 patients who had surgery after ivonescimab plus chemotherapy, but it had no control arm to test comparative benefit.
The paper appeared in Nature Medicine on Nov. 4, 2026, and Akeso, Inc. announced its publication Nov. 5. It describes an open-label, nonrandomized trial of 90 patients in China: 11 received ivonescimab alone and 79 received it with platinum-paclitaxel chemotherapy before surgery. The protocol included ivonescimab after surgery as well, but 72 patients started at least one postoperative cycle: 10 in the monotherapy cohort and 62 in the combination cohort.
Response percentages were calculated among patients who had surgery. In the combination group, 47 of 67 surgery patients had a major pathological response, meaning 10% or less viable tumor remained; 34 had no viable cancer in the removed tumor and lymph nodes, a pathological complete response. In the monotherapy group, six of 10 surgery patients had a major response and three had a complete response; all 77 patients who underwent surgery across both groups had an R0 resection, meaning the tumor was removed completely.
The 12-month event-free survival estimate was 83.3% in the combination cohort and 81.8% in the monotherapy cohort. The Aug. 18, 2025, data cutoff came before researchers could estimate median event-free survival. Without a control group, the figures cannot establish whether ivonescimab, alone or with chemotherapy, improved outcomes compared with another regimen.
Grade 3 or higher treatment-related adverse events occurred in 24 of 79 patients on combination therapy (30.4%) and four of 11 on monotherapy (36.4%). No hemorrhages reached grade 3, and researchers attributed no deaths to treatment; one operation in the combination cohort was delayed after the patient developed abnormal vital capacity following preoperative treatment.
The paper did not include overall-survival data. The authors plan to report those analyses in future manuscripts, but gave no publication date.
