New Bispecific Antibody Drug Doubles Survival in Resistant Lung Cancer Patients

A phase III trial showed that izalontamab brengitecan nearly doubled progression-free survival in patients with EGFR-mutated lung cancer who had developed resistance to prior treatments. The drug, which targets both EGFR and HER3, achieved a median PFS of 11.1 months compared to 5.7 months with chemotherapy. It also demonstrated higher response rates and favorable interim overall survival data.

In a phase III trial known as PANKU-Lung01, conducted across 73 sites in China from May 2024 to September 2025, the bispecific antibody-drug conjugate izalontamab brengitecan (iza-bren) demonstrated a median progression-free survival (PFS) of 11.1 months compared to 5.7 months with standard chemotherapy (pemetrexed plus carboplatin or cisplatin), nearly doubling PFS in patients with EGFR-mutated non-small cell lung cancer who had progressed on third-generation EGFR tyrosine kinase inhibitors (TKIs). The trial, presented at the ESMO 2026 congress in Madrid and published in The Lancet, included 432 participants—mostly women, with a median age of around 60—and showed a confirmed objective response rate of 60.2% for iza-bren versus 34.5% for chemotherapy, with a median duration of response of 10.5 months versus 5.7 months. Interim overall survival data favored the new drug (not reached vs 19.4 months), though it remains immature. The drug targets both EGFR and HER3, aiming to overcome resistance mechanisms that limit current therapies. Li Zhang, MD, from Sun Yat-sen University Cancer Center, led the study and emphasized the urgent need for better options after TKI failure, as chemotherapy remains the standard despite limited efficacy. Iza-bren has already received FDA breakthrough therapy designation based on earlier phase I/II data and showed similar PFS benefits in a separate trial involving heavily pretreated breast cancer patients.

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