Seoul – September 16, 2026 -- Risvutatug rezetecan (Ris-Rez), a B7-H3-directed antibody-drug conjugate, reduced the risk of death by 54% compared with topotecan in patients with relapsed small-cell lung cancer, according to Phase III ARTEMIS-008 trial results presented at the IASLC 2026 World Conference on Lung Cancer.
Ris-Rez extends median overall survival to 18.5 months versus 10.3 months for topotecan
The multicenter, open-label trial (NCT06498479) randomized 461 patients in China 1:1 to receive Ris-Rez at 8.0 mg/kg every three weeks or topotecan at 1.2 mg/m2 on days 1 through 5 every three weeks. More than 80% of enrolled patients had previously received PD-(L)1 inhibitors. At the June 6, 2026 data cutoff, after a median follow-up of 12.2 months, the hazard ratio for death favored Ris-Rez at 0.46 (95% CI, 0.35–0.62; P0.0001), with the survival benefit consistent across relevant subgroups.
Response rates nearly quintuple those seen with topotecan
Blinded independent central review showed median progression-free survival of 7.2 months with Ris-Rez versus 3.0 months with topotecan (HR 0.33; 95% CI, 0.25–0.42). The objective response rate reached 58.3% with Ris-Rez compared with 12.6% for topotecan, while disease control rates were 90.4% versus 60.2%, respectively. Investigator-assessed outcomes matched the central review findings.
Grade 3+ treatment-related adverse events occur less often with Ris-Rez
Grade 3 or higher treatment-related adverse events were reported in 60.9% of patients on Ris-Rez versus 78.2% on topotecan. The most common high-grade toxicities were hematologic, including decreased neutrophil count, decreased white blood cell count, anemia, decreased lymphocyte count and decreased platelet count.
Professor Jie Wang of the National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences Peking Union Medical College in Beijing said the trial demonstrated a statistically significant and clinically meaningful overall survival benefit over topotecan, coupled with a favorable safety profile, in patients whose disease progressed after platinum-based therapy.
The trial's primary endpoint was overall survival, with progression-free survival, objective response rate, disease control rate and safety tracked as key secondary endpoints.