Risvutatug rezetecan extended median progression-free survival to 5.5 months vs 1.4 months with chemotherapy in pretreated osteosarcoma.
On October 26, 2026, Hansoh Pharmaceutical Group announced phase 3 results for risvutatug rezetecan (Ris-Rez),
"Osteosarcoma typically affects children and young adults, and for patients whose disease has returned or progressed following multiple treatments, there are no approved therapies and no clearly established standard of care," said
After a median follow-up of 7.1 months, Ris-Rez reduced the risk of disease progression or death by 67% (hazard ratio, 0.33; 95% confidence interval, 0.20-0.55; p<.0001).¹ Median PFS, assessed by an independent review committee, was 5.5 months with Ris-Rez vs 1.4 months with chemotherapy.¹
On July 28, 2026, GSK announced that Hansoh's ARTEMIS-011 trial had met its primary endpoint of PFS.³ Secondary endpoints include overall survival, objective response rate, disease control rate, and duration of response.¹
Grade 3 or higher treatment-related adverse events (TRAEs) occurred in 93% of patients receiving Ris-Rez at 12 mg/kg and 83% of those receiving chemotherapy. In both arms, the most common were hematologic events.¹ TRAEs led to discontinuation in 4% of patients receiving Ris-Rez and 2% receiving chemotherapy.¹ According to GSK, safety findings were consistent with prior findings in this tumor type.¹
The 12 mg/kg dose in ARTEMIS-011 is higher than the 8 mg/kg dose used in the ARTEMIS-008 trial in small cell lung cancer. The higher dose was selected to account for potential difficulty in penetrating bone tissue.¹
Osteosarcoma is the most common primary bone cancer and mainly affects children and young adults.¹,⁴ Treatment options after first-line chemotherapy are severely limited, and no therapies are approved after 2 prior lines of treatment.¹
"For patients with relapsed osteosarcoma, where treatment options are extremely limited, these findings are particularly important," said
GSK
ARTEMIS-011 enrolled only patients in China. GSK said its global trial is designed to further characterize the benefit-risk profile in a broader population. The open-label design may introduce bias, although the primary endpoint was independently assessed. Follow-up was relatively short, overall survival data were not reported, and grade 3 or higher TRAEs were frequent. Full peer-reviewed results have not been published, and Ris-Rez is not approved for osteosarcoma in any market.
