Akeso's ivonescimab shows deep pathological responses in Phase 2 perioperative lung cancer trial

What's the deal? On 5 November 2026, Akeso Biopharma announced that results from a Phase 2 clinical trial of its cancer drug ivonescimab, in the perioperative treatment of resectable non-small cell lung cancer, were published in the journal Nature Medicine. Perioperative means the drug is given before and after surgery: patients received ivonescimab (either alone or combined with chemotherapy) before their tumour was removed, and continued it afterwards. Ivonescimab is a bispecific antibody, engineered to block two targets at once — PD-1, which tumours use to switch off immune cells, and VEGF, a protein that helps tumours grow blood vessels.

Why it matters: The trial showed high rates of pathological response, meaning the tumour tissue removed at surgery was largely or completely wiped out. In the ivonescimab-plus-chemotherapy arm, 70.1% of patients who underwent surgery achieved a major pathological response and 50.7% had no detectable tumour cells left (a complete pathological response); the single-agent arm achieved 60.0% and 30.0% respectively. All patients who reached surgery had a complete (R0) removal of their tumour, and event-free survival at 12 months exceeded 80% in both arms. Activity was notably strong in patients with squamous-cell tumours (81.5% major response) and in stage III disease, and was comparable in patients whose tumours do not express PD-L1. The safety profile was manageable, with no grade 3 or higher bleeding events and no operations cancelled for treatment-related reasons.

Read more: Akeso Biopharma, 05 November 2026