Zai Lab has launched a Phase III trial evaluating DLL3 antibody-drug conjugate (ADC) zocilurtatug pelitecan versus investigator's choice therapy including tarlatamab, topotecan or amrubicin in 665 patients with recurrent small cell lung cancer (SCLC). The open-label randomised study's primary endpoints include confirmed objective response rate (cORR) and overall survival (OS). Phase I data previously showed 67% unconfirmed response rate in a second-line setting, with 79% response at 1.6 mg/kg dosing. Brain metastasis patients achieved 68% ORR including 86% in radiotherapy-naive population, demonstrating central nervous system (CNS) activity.

The safety profile showed manageable toxicity with 6% grade-three or higher treatment-related adverse events (TRAEs) at doses below 2.0 mg/kg (primarily anaemia and neutropoenia) without treatment discontinuations. Higher dose cohorts reported 23% grade-three or higher events including two grade-three or higher interstitial lung disease (ILD) cases at 2.0 and 2.4 mg/kg levels. Zai licensed global rights from MediLink Therapeutics in April 2023.

According to PharmCube's NextBiopharm® database, the new study has positioned zocilurtatug pelitecan as the most developed DLL3 ADC globally. Click here to request a free trial for NextBiopharm®.