Contact: Chris Martin, MPH/IASLC Media Relations/cmartin@davidjamesgroup.com
(Barcelona, Spain — September 6, 2025, 5:45 p.m. CEST / UTC +2 ) — A novel antibody-drug conjugate (ADC), iza-bren (BL-B01D1), demonstrated encouraging safety and efficacy results in previously treated patients with EGFR-mutated non-small cell lung cancer (NSCLC), according to findings presented at the International Association for the Study of Lung Cancer (IASLC) 2025 World Conference on Lung Cancer (WCLC).
Iza-bren is a first-in-class EGFR x HER3 bispecific ADC linked to a novel topoisomerase I inhibitor payload (Ed-04). The drug was evaluated in two Phase I/II studies in patients with locally advanced or metastatic solid tumors, including EGFR-mutated NSCLC. Patients received a range of doses on different schedules, including day 1 and day 8 every 3-week cycle (D1D8 Q3W) and day 1 every 3-week cycle (D1 Q3W).
Among the 171 EGFR-mutated NSCLC patients, 50 patients who received prior TKI and chemo-naïve were treated at 2.5 mg/kg D1D8 Q3W. In this subgroup, the objective response rate (ORR) was 66.0%, the confirmed ORR (cORR) was 56.0%, the median progression-free survival (mPFS) was 12.5 months, the median duration of response (mDOR) was 13.7 months, and the median overall survival (mOS) was not reached with a 12-mo OS rate of 80.3%.
According to the lead investigator Dr. Wenfeng Fang from Sun Yat-sen University Cancer Center, Guangzhou, China, the safety profile was manageable. The most frequent hematologic treatment-related adverse events (TRAEs) were anemia (90.6%), leukopenia (80.7%), neutropenia (78.4%), and thrombocytopenia (74.3%). The most frequent non-hematologic TRAEs included nausea, alopecia, and asthenia. Only 1.2% of patients were discontinued due to TRAEs, and no treatment-related death was observed.
“This early data suggests iza-bren may offer a promising treatment option for patients with EGFR-mutated NSCLC,” said Dr. Fang. “Phase III registrational study of iza-bren as monotherapy in EGFR-mutated NSCLC after progression on a third generation TKI is ongoing in China.”
About the IASLC:
The International Association for the Study of Lung Cancer (IASLC) is the only global organization dedicated solely to the study of lung cancer and other thoracic malignancies. Founded in 1974, the association's membership includes more than 10,000 lung cancer specialists across all disciplines in over 100 countries. The IASLC publishes the Journal of Thoracic Oncology and is committed to advancing research, education, and multidisciplinary collaboration to conquer lung and thoracic cancers worldwide. Learn more at www.iaslc.org.
About the WCLC:
The World Conference on Lung Cancer (WCLC) is the world’s largest meeting dedicated to lung cancer and other thoracic malignancies, attracting nearly 7,000 researchers, physicians, and specialists from over 100 countries. The conference promotes awareness, collaboration, and innovation across the spectrum of lung cancer research and care. For more information, visit https://wclc.iaslc.org/.