Iza-bren nearly doubles progression-free survival in Phase III EGFR-mutated lung cancer trial
Posted on October 26, 2026
SystImmune and Bristol Myers Squibb have reported positive Phase III results showing that izalontamab brengitecan, also known as iza-bren, significantly improved progression-free survival in patients with previously treated EGFR-mutated non-small cell lung cancer.
The findings come from the PANKU-Lung01 study and were presented in a late-breaking oral session at the 2026 European Society for Medical Oncology Congress in Madrid.
The results were also published simultaneously in The Lancet.
Iza-bren is an investigational dual-targeting EGFRxHER3 bispecific antibody drug conjugate designed to target two proteins involved in tumour growth and treatment resistance.
The study enrolled patients with EGFR-mutated non-squamous non-small cell lung cancer whose disease had progressed following treatment with an EGFR tyrosine kinase inhibitor.
A total of 216 patients received iza-bren, while 206 were treated with platinum-based chemotherapy.
At a median follow-up of 14.6 months for progression-free survival, iza-bren significantly improved the study’s primary endpoint.
Median progression-free survival assessed by blinded independent central review reached 11.1 months with iza-bren compared with 5.7 months with chemotherapy.
This corresponded to a hazard ratio of 0.40, with a 95% confidence interval of 0.31 to 0.51 and a p value below 0.0001.
The results therefore showed an approximately 60% reduction in the risk of disease progression or death with iza-bren compared with platinum-based chemotherapy.
The confirmed objective response rate was also higher with the investigational treatment.
Among patients receiving iza-bren, 60.2% achieved a confirmed tumour response compared with 34.5% of those receiving chemotherapy.
Median duration of response was 10.4 months with iza-bren versus 5.7 months in the chemotherapy group.
Overall survival data were not yet mature at the time of the analysis, although the companies reported a favourable trend towards improved survival with iza-bren.
Li Zhang, Professor and Chief Lung Cancer Expert at Sun Yat-sen University Cancer Center, said treatment options remain limited after EGFR-mutated lung cancer progresses following EGFR-targeted therapy.
He said the PANKU-Lung01 findings suggest that iza-bren could offer patients a longer period before disease progression compared with chemotherapy.
The safety profile was considered manageable and no new safety signals were identified.
Grade 3 or higher treatment-related adverse events were primarily haematological.
Only 1.9% of patients receiving iza-bren discontinued treatment because of treatment-related adverse events.
Interstitial lung disease was uncommon, with two adjudicated cases reported among patients receiving iza-bren, representing 0.9% of the group.
One case was Grade 3 and the other was Grade 1.
Jonathan Cheng, Chief Medical Officer of SystImmune, said the findings support dual targeting of EGFR and HER3 as a potential strategy for patients whose disease develops resistance following EGFR TKI treatment.
Cristian Massacesi, MD, Executive Vice President, Chief Medical Officer and Head of Development at Bristol Myers Squibb, said the results add to a growing body of evidence supporting iza-bren across multiple tumour types.
Iza-bren has now demonstrated clinical benefit in Phase III studies across five indications, including previously treated EGFR-mutated non-small cell lung cancer, nasopharyngeal carcinoma, oesophageal squamous cell carcinoma, advanced triple-negative breast cancer and previously treated HR-positive, HER2-negative breast cancer.
The treatment has also received Breakthrough Therapy Designation from the U.S. Food and Drug Administration for previously treated advanced EGFR-mutated non-small cell lung cancer.
Outside China, iza-bren is being jointly developed by SystImmune and Bristol Myers Squibb under a collaboration and exclusive licensing agreement.
Related Topics and Keywords
ADC, Biopharma, bispecific antibody drug conjugate, Bristol-Myers Squibb, clinical trials, egfr, egfr mutated lung cancer, EGFR NSCLC, ESMO 2026, HER3, Iza-bren, Izalontamab Brengitecan, lung cancer, non-small cell lung cancer, objective response rate, Oncology, PANKU-Lung01, pharma news, phase III, platinum chemotherapy, progression-free survival, SystImmune, targeted therapy
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