NANJING, China, May 18, 2026
Leads Biolabs announced that its proprietary PD-L1/4-1BB bispecific antibody Opamtistomig (LBL-024) has received approval from China’s Center for Drug Evaluation (CDE) under the National Medical Products Administration (NMPA) to initiate a pivotal Phase III clinical trial for the first-line treatment of advanced extrapulmonary neuroendocrine carcinoma (EP-NEC). The approval represents a major advancement for the company’s immuno-oncology pipeline and could significantly reshape treatment strategies for one of the most aggressive and difficult-to-treat neuroendocrine cancers. The study will evaluate Opamtistomig in a randomized, double-blind, multicenter Phase III setting and marks the transition of the therapy from late-line monotherapy development into frontline combination treatment. The approval also strengthens Leads Biolabs’ position in the global bispecific antibody market and highlights growing momentum in next-generation checkpoint immunotherapy development.
Opamtistomig Expands From Late-Line Therapy to Frontline Treatment
The newly approved Phase III trial is being led by Professor Lin Shen of Peking University Cancer Hospital and was supported by promising efficacy and safety data generated from a completed Phase Ib/II proof-of-concept clinical study. According to the company, detailed clinical findings are expected to be presented during the 2026 European Society for Medical Oncology (ESMO) Congress, where additional efficacy and survival data could further validate Opamtistomig’s therapeutic potential in EP-NEC patients. Previously, Opamtistomig had already secured regulatory clearance for a pivotal single-arm registration study in third-line and later EP-NEC patients, making this latest approval a significant expansion of its clinical scope and addressable patient population. The advancement from salvage therapy into first-line treatment is considered a critical milestone because frontline settings generally offer larger commercial opportunities, broader patient access, and higher clinical impact.
Leads Biolabs also confirmed plans to submit a Biologics License Application (BLA) during the third quarter of 2026 seeking approval for Opamtistomig as a monotherapy in advanced EP-NEC patients who have exhausted multiple prior treatments. Beyond EP-NEC, the company is aggressively expanding the molecule into additional oncology indications including non-small cell lung cancer (NSCLC), small cell lung cancer (SCLC), biliary tract cancer (BTC), and ovarian cancer. The company stated that at least two additional pivotal Phase III studies are currently being prepared as part of a broader multi-tumor development strategy. To date, Opamtistomig has demonstrated first- or best-in-class potential across multiple Phase II and registrational studies, positioning it as one of the more closely watched bispecific antibody programs emerging from China’s biotechnology sector.
Strong Need for New Treatments in EP-NEC
Extrapulmonary neuroendocrine carcinoma (EP-NEC) remains one of the most aggressive and therapeutically underserved cancer types globally. The disease is often categorized as an immunologically “cold” tumor, meaning it typically responds poorly to conventional immunotherapy approaches due to limited immune-cell infiltration. Currently, no therapy has received full regulatory approval specifically for EP-NEC anywhere in the world. Standard frontline treatment continues to rely on platinum-based chemotherapy regimens that deliver only modest clinical benefit, with reported objective response rates ranging from 30% to 50% and a median overall survival of approximately one year. These limitations have intensified the search for novel therapeutic strategies capable of generating stronger and more durable anti-tumor responses.
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According to Leads Biolabs Chief Medical Officer Dr. Charles Cai, regulatory discussions with the CDE demonstrated strong recognition of the urgent unmet medical need in EP-NEC and acknowledged the encouraging clinical signals observed with Opamtistomig. The company believes the molecule’s dual-targeting mechanism involving PD-L1 blockade and 4-1BB immune co-stimulation may enhance anti-tumor immune activation more effectively than traditional checkpoint inhibitors alone. If successful, Opamtistomig could become one of the first globally approved targeted immunotherapies specifically developed for EP-NEC, potentially changing the treatment paradigm for patients with limited survival prospects and few therapeutic options.
Source: Leads Biolabs press release
