GlaxoSmithKline presented encouraging phase I/II ARROS-1 trial results for its lung cancer therapy jideytro (zidesamtinib), reporting high response rates in treatment-naïve patients with ROS1-positive non-small cell lung cancer.
Data from the global, single-arm trial, with a cut-off date of April 16, 2026, were presented at the 2026 World Conference on Lung Cancer in Seoul, South Korea. Among 94 treatment-naïve patients analyzed, the objective response rate reached 94% following a median follow-up of 15.2 months, while the complete response rate stood at 15%. Progression-free survival was 90% at 12 months, with both median duration of response and median progression-free survival not yet reached at the time of analysis.
In the brain metastases subgroup, all 10 patients with measurable brain lesions at baseline responded to treatment, with 70% achieving complete clearance of detectable brain tumors. Intracranial responses were maintained in 78% of these patients at 12 months.
The safety profile showed peripheral edema, weight increase, elevated creatine phosphokinase, dysgeusia, and increased aspartate aminotransferase as the most common treatment-related adverse events. Dose reductions due to adverse events occurred in 11% of patients, while treatment discontinuation due to adverse events was reported by just 1%.
ROS1 mutations occur in approximately 2% of non-small cell lung cancers, contributing to an estimated 50,000 new diagnoses globally each year. Jideytro received U.S. FDA approval in July 2026 for patients previously treated with a tyrosine kinase inhibitor but is not yet approved for first-line use.
GSK plans to submit a supplemental new drug application to the FDA this year seeking approval for the treatment-naïve indication.












