Clinical-stage biotechnology company Nanjing Leads Biolabs Co Ltd (HK:9887) announced on Monday that its proprietary PD-L1/4-1BB bispecific antibody, Opamtistomig (LBL-024), has received approval from the Center for Drug Evaluation (CDE) of China's National Medical Products Administration (NMPA) to launch a pivotal Phase III clinical trial for the first-line treatment of advanced extrapulmonary neuroendocrine carcinoma (EP-NEC).

This approval marks the successful advancement of Opamtistomig's clinical development in EP-NEC from late-line monotherapy to first-line combination therapy. The therapy had previously received CDE approval for a pivotal single-arm registration trial in 3L+ EP-NEC patients, and the latest approval further expands its addressable patient population.

The approval was based on the promising efficacy and favourable safety profile demonstrated by Opamtistomig in a successfully completed Phase Ib/II proof-of-concept study.

Leads Biolabs plans to submit a Biologics License Application (BLA) in the third quarter of 2026 for Opamtistomig as a single agent for the treatment of advanced EP-NEC in the third-line or later setting. In parallel, the company is advancing multiple proof-of-concept studies and preparing to initiate at least two additional Phase III clinical trials for Opamtistomig, exploring its application across 13 solid tumour indications, including first-line NSCLC, first-line BTC, small cell lung cancer, and ovarian cancer.