The U.S. Food and Drug Administration approved GSK’s Jideytro, known generically as zidesamtinib, on July 22, 2026, for adults with locally advanced or metastatic ROS1-positive non-small cell lung cancer who have received at least one prior tyrosine kinase inhibitor. The approval arrived nearly two months ahead of schedule.
The regulatory decision marks the first lung cancer approval for GSK plc, which brought the targeted therapy into its portfolio through its acquisition of Nuvalent, Inc. Originally facing a target action date of September 18, 2026, the therapy cleared the agency early under the Real-Time Oncology Review pilot program and Assessment Aid framework, building upon earlier Breakthrough Therapy and Orphan Drug designations.
Clinical Efficacy and Trial Outcomes in Previously Treated Patients
Regulatory approval was granted based on data from the global, multicenter, single-arm, open-label ARROS-1 phase I/II trial (NCT05118789). The primary efficacy population comprised 117 evaluable patients with locally advanced or metastatic ROS1-positive non-small cell lung cancer who had undergone prior treatment. Among them, 59 patients had received one prior ROS1 tyrosine kinase inhibitor, while 58 patients had received two or more prior inhibitors, including regimens containing lorlatinib, repotrectinib, and taletrectinib.
Evaluated by blinded independent central review under RECIST v1.1 criteria, the overall confirmed objective response rate reached 44% with a 95% confidence interval spanning 34% to 53%. The durability of these responses proved notable: 82% of responding patients maintained their response for six months or longer, and 69% sustained their response for at least 12 months. Patients with a single prior tyrosine kinase inhibitor achieved an objective response rate of 49% (95% CI: 36, 63), whereas those who had undergone two or more prior inhibitors registered a 38% response rate (95% CI: 26, 52).
Expansion Data in TKI-Naive Patients and Safety Profile
Fresh data presented at the International Association for the Study of Lung Cancer 2026 World Conference on Lung Cancer in Seoul, Republic of Korea, detailed zidesamtinib performance in patients who had not previously received tyrosine kinase inhibitor therapy. Among 94 efficacy-evaluable, TKI-naive patients in the global Phase I/II ARROS-1 trial, the objective response rate reached 94%, with 88 patients responding. The nine-month duration-of-response rate stood at 94%, and the 12-month rate registered at 86%.
The trial also recorded substantial intracranial activity. In a subset of 10 evaluable patients presenting with central nervous system metastases, the intracranial objective response rate reached 100%, which included a 70% intracranial complete response rate. The nine-month intracranial duration-of-response rate was 100%, and the 12-month rate reached 78%.
Zidesamtinib demonstrated clinically meaningful activity in TKI-naive patients with ROS1-positive NSCLC, with a safety profile consistent with previous reports and low rates of dose reduction and discontinuation.
Alexander Drilon, Memorial Sloan Kettering Cancer Center and Weill Cornell Medical Center
Across a pooled safety population of 446 patients receiving the recommended 100 mg oral once-daily dose, the most frequent adverse reactions included edema, peripheral neuropathy, constipation, fatigue, and dyspnea. More detailed trial safety tracking involving 532 total patients identified peripheral edema in 34% of participants, increased weight in 18%, elevated blood creatine phosphokinase in 18%, dysgeusia in 17%, and increased aspartate aminotransferase in 15%. Treatment-related adverse events resulted in dose reductions for 11% of patients and treatment discontinuation for 1%.
Broader Portfolio Context and Patient Impact
Approximately 50,000 individuals worldwide receive a diagnosis of ROS1-positive non-small cell lung cancer annually, a patient group often characterized by non-smokers in their forties and fifties who require long-term disease management. Tony Wood, Chief Scientific Officer at GSK, emphasized that the rapid progression of Jideytro from development to approval demonstrates both scientific strength and urgent clinical demand.
“For patients, the goal is not just more time, but quality time to live life as normally as possible while on treatment. The ROS1-positive community is deeply invested in advancing care with treatments that are effective and tolerable. Today’s approval gives patients and their doctors an important new option and represents meaningful progress for our community.”
Janet Freeman-Daily, The ROS1ders
The regulatory clearance represents the first oncology approval for GSK, which is advancing additional compounds inherited from Nuvalent.
Related reading
- What Does [Term] Mean? Signs and Symptoms
- How Reading for Pleasure Boosts Brain Health and Wellbeing
- Breakthrough Salk Study Uncovers Mechanism Behind Immunotherapy Resistance: Interferons, Mitochondrial Dysfunction, and PGE2″ Interferons, mitochondrial dysfunction and PGE2: Salk study reveals mechanism behind immunotherapy resistance. Boost its search engine visibility with relevant keywords for maximum impact. Immunotherapy resistance remains one of the biggest hurdles in cancer treatment. According to a recent study published in the journal Nature Communications, scientists at the Salk Institute have made a groundbreaking discovery that sheds light on the underlying mechanisms behind this resistance. The study reveals that interferons, a type of protein that plays a crucial role in the immune system, can contribute to mitochondrial dysfunction in cancer cells. This dysfunction can lead to the production of prostaglandin E2 (PGE2), a molecule that promotes tumor growth and resistance to immunotherapy. In their study, the researchers found that PGE2 production was a key factor in the development of immunotherapy resistance in cancer cells. The team used a combination of experimental and computational models to investigate the relationship between interferons, mitochondrial dysfunction, and PGE2 production. The findings of the study suggest that targeting PGE2 production could be a potential strategy for overcoming immunotherapy resistance. The researchers propose that blocking PGE2 receptors or inhibiting its production could help restore the function of mitochondria in cancer cells, making them more susceptible to immunotherapy. The study’s authors hope that their findings will pave the way for the development of new therapies that can overcome immunotherapy resistance and improve treatment outcomes for cancer patients. Key Takeaways: – Interferons contribute to mitochondrial dysfunction in cancer cells – Mitochondrial dysfunction leads to PGE2 production, promoting tumor growth and resistance to immunotherapy – Targeting PGE2 production could be a potential strategy for overcoming immunotherapy resistance – Restoring mitochondrial function in cancer cells could make them more susceptible to immunotherapy Keywords: immunotherapy resistance, interferons, mitochondrial dysfunction, PGE2, Salk Institute, cancer treatment, breakthrough study, Nature Communications. (archyworldys.com)
