GSK’s Ris-Rez Meets Primary Endpoint In Phase III ARTEMIS-011 Trial, Reducing Risk Of Progression Or Death By 67%, Improving Median Progression-Free Survival To 5.5 Months Vs. 1.4 Months With Chemotherapy In Relapsed Or Refractory Osteosarcoma

Patients receiving Ris-Rez remained progression-free for a median of 5.5 months versus 1.4 months with comparator

Second positive phase III trial in China adds to growing body of late-stage evidence for Ris-Rez in different solid tumours

GSK’s global phase II trial is ongoing in advanced osteosarcoma and soft tissue sarcoma

GSK plc (LSE/NYSE:GSK) licensor Hansoh Pharmaceutical Group Co., Ltd., today announced positive results from its ARTEMIS-011 study, a pivotal phase III trial in China evaluating risvutatug rezetecan (Ris-Rez) in patients whose osteosarcoma had progressed or relapsed after at least two prior lines of systemic therapy. The trial met its primary endpoint, demonstrating a statistically significant and clinically meaningful improvement in progression-free survival (PFS) as assessed by an Independent Review Committee (IRC) versus chemotherapy.

In ARTEMIS-011, Ris-Rez reduced the risk of disease progression or death by 67% compared with chemotherapy, after a median follow-up of 7.1 months (HR, 0.33; 95% CI, 0.20-0.55; p<0.0001). Median PFS was 5.5 months with Ris-Rez versus 1.4 months with chemotherapy. The late-breaking results were presented during a Presidential Symposium session at the European Society for Medical Oncology (ESMO) Congress 2026 and will support a regulatory submission by Hansoh in China.