ZL-1310, a DLL3-targeted ADC, achieves a 68% response rate in relapsed/refractory ES-SCLC

Treatment options are limited for patients (pts) with extensive-stage small cell lung cancer (ES-SCLC) that progress after platinum-based chemotherapy (chemo). In a Phase I dose-escalation (n=28), ZL-1310, a DLL3 targeted ADC, delivered a 68% ORR (93% DCR) across all DLL3 levels—including an 80% response in patients with brain metastases and prior similar treatments (tarlatamab) —with Grade ≥3 TRAEs in 39% (e.g., anemia, neutropenia, thrombocytopenia, interstitial lung disease) and dose-proportional PK showing low payload accumulation. Some patients needed a lower dose (18%) and/or had to stop treatment due to side effects (18%).