Boehringer Ingelheim & Zai Lab launch DLL3‑targeting T‑cell engager + ADC trial in SCLC and NECs

Key highlights
  • Boehringer Ingelheim and Zai Lab will run a Phase Ib/II trial combining obrixtamig (DLL3/CD3 T‑cell engager) with zocilurtatug pelitecan (zoci, DLL3‑targeting ADC) in ES‑SCLC and other NECs.
  • Obrixtamig is a bispecific DLL3/CD3 T‑cell engager from Boehringer Ingelheim, evaluated in DAREON‑8 and advancing to global Phase III (DAREON‑Lung‑1, NCT07472517).
  • Zocilurtatug pelitecan (zoci) is Zai Lab’s DLL3 ADC carrying a camptothecin‑derived topoisomerase I payload via the TMALIN platform, showing systemic and intracranial responses and advancing to a global Phase III (DLLEVATE).
  • Zai Lab will supply the ADC; Boehringer Ingelheim will sponsor and run day‑to‑day clinical operations, and each company retains rights to its respective asset.

Collaboration

Boehringer Ingelheim and Zai Lab will run a Phase Ib/II study combining obrixtamig (DLL3/CD3 T‑cell engager) with zocilurtatug pelitecan (zoci, DLL3‑targeting ADC) in poorly differentiated neuroendocrine carcinomas and extensive‑stage small cell lung cancer to assess safety, tolerability and initial clinical activity.

Obrixtamig

Obrixtamig is a bispecific DLL3/CD3 T‑cell engager; in the global Phase I first‑line ES‑SCLC study DAREON‑8 (given with chemotherapy and atezolizumab) it showed early signs of clinical activity and a manageable safety profile and is advancing to a global Phase III trial (DAREON‑Lung‑1, NCT07472517); it has received FDA Fast Track and Orphan Drug designations for neuroendocrine carcinomas.

Zocilurtatug pelitecan (zoci)

Zoci is a DLL3‑targeting ADC comprised of a humanized anti‑DLL3 antibody linked to a camptothecin‑derived topoisomerase I payload via the TMALIN platform; updated global Phase I data in previously treated ES‑SCLC report systemic and intracranial responses, including in patients with brain metastases, and a favorable safety profile, supporting advancement to a global Phase III registrational study (DLLEVATE) and evaluation in NECs; zoci has FDA Orphan Drug and Fast Track designations for SCLC.

Operational terms

Under the agreement Zai Lab will supply the DLL3 ADC and Boehringer Ingelheim will sponsor and manage day‑to‑day clinical operations; each company retains rights to its respective asset.