SystImmune Announces iza-bren Meets One of the Dual Primary Endpoints in the BL-B01D1-303 Trial in Recurrent or Metastatic NPC Patients with Results Presented at ESMO 2025
SystImmune announced positive topline results from the BL-B01D1-303 phase III trial for iza-bren in recurrent or metastatic nasopharyngeal carcinoma (NPC) patients, with the study meeting one of its dual primary endpoints:
a statistically significant and clinically meaningful improvement in BICR-assessed objective response rate (ORR) compared to chemotherapy.15
Results were presented as a late-breaking oral presentation at the European Society for Medical Oncology (ESMO) Congress in October 2025, marking the first data readout for iza-bren from a registration-enabling study in China.12
Iza-bren (izalontamab brengitecan) is a first-in-class bispecific antibody-drug conjugate targeting both EGFR and HER3, developed by Biokin in China and jointly developed outside China by SystImmune and Bristol Myers Squibb.125
The trial enrolled patients who had progressed on at least two prior chemotherapy lines, including platinum-based therapy and a PD-1/PD-L1 inhibitor.12
Based on these results, a New Drug Application (NDA) for iza-bren for the treatment of recurrent or metastatic NPC has been submitted to China's Center for Drug Evaluation.1
The BL-B01D1-303 trial is a randomized, open-label, multicenter phase III study (NCT06118333) conducted in China.12
Sources:
1. https://www.biospace.com/press-releases/systimmune-announces-iza-bren-meets-one-of-the-dual-primary-endpoints-in-the-bl-b01d1-303-trial-in-recurrent-or-metastatic-npc-patients-with-results-presented-as-a-late-breaking-oral-presentation-at-esmo
2. https://systimmune.com/news---systimmune-inc-to-present-new-clinical-data-on-izalontamab-brengitecan-and-bl-m07d1-highlighting-strength-of-differentiated-antibody-drug-conjugate-adc-platform