Summit announces ivonescimab, chemo showed improvement in primary endpoint

rSummit Therapeutics (SMMT) announced results from the Phase III HARMONi-6 trial, conducted in China and sponsored by our partner, Akeso (AKESF), featuring the investigational bispecific antibody, ivonescimab. The data was presented as part of the Presidential Symposium at the European Society for Medical Oncology 2025 Congress, ESMO 2025, in Berlin, Germany. In the HARMONi-6 planned interim analysis of progression-free survival, PFS, ivonescimab in combination with chemotherapy demonstrated a statistically significant improvement in the primary endpoint, PFS, by Independent Radiologic Review Committee, IRRC, when compared to tislelizumab in combination with chemotherapy, achieving a hazard ratio of 0.60. A clinically meaningful benefit was demonstrated across clinical subgroups, including those with either PD-L1 negative or positive expression. Both the overall response rate, ORR, measured according to RECIST v1.1 criteria, as well as the duration of response, DoR, were higher in patients treated with ivonescimab plus chemotherapy compared to those treated with tislelizumab plus chemotherapy.