GSK reported positive first global data for its investigational antibody-drug conjugate, risvutatug rezetecan (Ris-Rez), in patients with relapsed extensive-stage small cell lung cancer (ES-SCLC). [1, 2] The results come from a Phase Ib dose-optimization study presented at the European Society for Medical Oncology (ESMO) Congress. [3, 8]
At the 8 mg/kg dose, Ris-Rez achieved a 61% confirmed objective response rate (ORR). [4, 5] The lower dose produced a 32% ORR. [4, 5] The drug had a manageable safety profile, although higher-grade side effects were more common at the more effective dose. [5]
The findings supported selection of the 8 mg/kg dose for the ongoing global Phase III study. [1, 4] They also build on recently reported positive Phase III results from a trial of Ris-Rez in China. [1]