GSK unveils positive registrational data that could expand Jideytro into first line treatment for ROS1-positive non small cell lung cancer

GSK has recently announced positive results from the registrational Phase I/II ARROS-1 trial, which evaluated Jideytro in patients with advanced or metastatic ROS1-positive non small cell lung cancer who had not previously been treated with a tyrosine kinase inhibitor. The findings were presented during a Presidential Symposium session at the 2026 World Conference on Lung Cancer in Seoul, South Korea, and will support a planned supplemental New Drug Application to the U.S. FDA this year aimed at expanding Jideytro’s indication to include first line treatment.

Among the 94 TKI-naïve patients included in the analysis, zidesamtinib achieved a clinically meaningful 94 percent objective response rate, including a 15 percent complete response rate (14 of 94), after a median follow up of 15.2 months. Responses proved durable, with 94 percent of patients still responding to treatment at nine months and 86 percent at 12 months. Progression free survival stood at 90 percent at 12 months. Median duration of response and median progression free survival had not yet been reached at the time of analysis. All patients with measurable brain metastases at baseline responded to zidesamtinib, and 70 percent achieved complete clearance of detectable brain tumors (7 of 10). At 12 months, 78 percent of patients maintained an intracranial response, and no central nervous system progression events occurred among patients who did not have brain metastases at baseline.

Hesham Abdullah, senior vice president and global head of oncology research and development at GSK, said the results show a combination of high response rates alongside a tolerability profile that allowed most patients to remain on treatment. He said these findings point to the potential for zidesamtinib to offer a differentiated profile as a first line treatment for patients with ROS1-positive NSCLC, a setting where maintaining long term disease control, managing spread to the brain, and limiting treatment related side effects continue to pose significant challenges. He said GSK is looking forward to sharing the data with regulators.

Low rates of treatment discontinuation were observed, consistent with prior safety reports for zidesamtinib. The most common treatment related adverse events, occurring in 15 percent or more of patients, included peripheral oedema, weight increase, elevated blood creatine phosphokinase, altered taste, and elevated aspartate aminotransferase, most of which were low grade. Treatment related adverse events led to dose reductions in 11 percent of patients and discontinuation in 1 percent.

Alexander Drilon, MD, primary investigator for ARROS-1 and chief of the Early Drug Development Service at Memorial Sloan Kettering Cancer Center, said patients with ROS1-positive NSCLC may remain on treatment for many years while continuing to work, care for their families, and go about daily life. He said these patients need treatments that provide lasting disease control, including within the brain, while minimizing side effects and disruptions to treatment. He said the durable responses and low discontinuation rates observed in ARROS-1 represent encouraging progress toward meeting these long term treatment needs.

Zidesamtinib is not currently approved anywhere in the world for use as a first line therapy. In July 2026, the FDA approved zidesamtinib for patients with ROS1-positive NSCLC who had previously been treated with a tyrosine kinase inhibitor.

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Related Topics and Keywords

GSK, Jideytro (zidesamtinib), lung cancer, ROS1-positive, ROS1-positive non-small cell lung cancer