Priority Review Granted to PD-L1/4-1BB Bispecific Antibody Opamtistomig, Accelerating Commercialization and Addressing Unmet Need in EP-NEC

NANJING, China, July 10, 2026 /PRNewswire/ -- Nanjing Leads Biolabs Co., Ltd. ("Leads Biolabs" or the "Company," Stock Code: 9887.HK) today announced that the biologics license application (BLA) for Opamtistomig (LBL-024, a PD-L1/4-1BB bispecific antibody) as monotherapy for the treatment of advanced extrapulmonary neuroendocrine carcinoma (EP-NEC) has been approved by the Center for Drug Evaluation (CDE) of the National Medical Products Administration (NMPA) of the People's Republic of China for inclusion in the priority review and approval procedure. This BLA submission is based on the positive results from a pivotal registrational clinical study led by Professor Shen Lin of Peking University Cancer Hospital, which was designed to evaluate the efficacy and safety of Opamtistomig in patients with advanced EP-NEC whose disease had progressed following two or more prior lines of systemic therapy.

Under the relevant PRC regulations, the review timeline for a BLA included in the priority review and approval procedure is 130 working days, as compared with 200 working days under the ordinary review procedure. The inclusion of Opamtistomig in the priority review process represents a key milestone toward its commercialization, providing clarity and visibility on its expected approval timeline. The Company is actively advancing relevant pre-launch commercialization preparations.

Executive Commentary

Dr. Charles Cai, Chief Medical Officer of Leads Biolabs, stated: "The differentiated mechanism of Opamtistomig is translating into broad clinical value validation across multiple indications. Beginning with EP-NEC, a highly aggressive immune-cold tumor for which no globally approved therapy currently exists, and extending to larger indications such as NSCLC and BTC, we have strategically and systematically built a comprehensive clinical development program. Across these indications, we continue to observe meaningful survival benefits and encouraging efficacy signals. We remain committed to accelerating the clinical development of Opamtistomig and unlocking its full potential as a next-generation cornerstone immunotherapy."

Dr. Xiaoqiang Kang, Founder, Chairman, CEO of Leads Biolabs, added: "The inclusion of Opamtistomig's BLA in China's priority review is a pivotal step in Leads Biolabs' transition toward commercialization. This milestone not only reflects our decade-long commitment to differentiated innovation, but also underscores the regulatory authorities' strong emphasis on addressing unmet medical needs. We will work closely with the CDE throughout the review process and strive to bring this innovative therapy to patients as quickly as possible."

About EP-NEC

EP-NEC is a highly aggressive immunologically cold tumor for which no therapy has been approved by any regulatory authority worldwide. Platinum-based chemotherapy remains the standard first-line treatment for patients with advanced EP-NEC, with a median overall survival (mOS) of approximately one year. However, there are no effective treatment options following progression on first-line platinum-based chemotherapy. For patients who have received two or more prior lines of systemic therapy, currently available later-line treatment options provide very limited clinical benefit, with reported objective response rates (ORR) ranging from 0% to 10% and a mOS of only three to four months. As such, EP-NEC represents an area of substantial unmet medical need, underscoring the urgent need for new and effective treatment approaches.

About Opamtistomig

Opamtistomig (LBL-024) is emerging as a next-generation pan-cancer backbone therapy with potential overall survival (OS) benefit that simultaneously targets PD-L1 and the co-stimulatory receptor 4-1BB. Developed using Leads Biolabs' proprietary X-Body bispecific platform, Opamtistomig is designed to simultaneously block PD-1/L1 immune suppression and conditionally activate 4-1BB, an agonist pathway, resulting in a potent and synergistic anti-tumor immune response. It has a safety profile comparable to PD-1/PD-L1 inhibitors and demonstrates broader-spectrum anti-cancer potential. To date, Opamtistomig has demonstrated first- or best-in-class potential in Phase II or registrational clinical trials across four indications: non-small cell lung cancer (NSCLC), small cell lung cancer (SCLC), biliary tract cancer (BTC), and extrapulmonary neuroendocrine carcinoma (EP-NEC).

As the first 4-1BB–targeting bispecific antibody globally to advance to a single-arm pivotal trial as monotherapy, Opamtistomig has been evaluated in 13 solid tumor indications in China, including 1 pivotal registration trial and 8 proof-of-concept studies. These cover EP-NEC, NSCLC, SCLC, BTC, ovarian cancer (OC), esophageal squamous cell carcinoma (ESCC), hepatocellular carcinoma (HCC), gastric cancer (GC), triple-negative breast cancer (TNBC), malignant melanoma, and other areas with high unmet medical needs.

Mechanistically, 4-1BB agonism can reactivate exhausted T cells and promote robust T-cell proliferation, offering significant promise for PD-1/PD-L1–resistant or immunologically "cold" tumors. Recognizing its clinical potential, Opamtistomig received Breakthrough Therapy Designation (BTD) from China's National Medical Products Administration (NMPA) in October 2024, and Orphan Drug Designation (ODD) from the U.S. Food and Drug Administration (FDA) for the treatment of neuroendocrine carcinoma in November 2024. Additionally, in January 2026, Opamtistomig was granted Fast Track Designation (FTD) by the FDA and ODD by the European Commission for the treatment of EP-NEC, further underscoring its potential to address unmet medical needs in this patient population.

About Leads Biolabs

Founded in 2012, Leads Biolabs is a clinical-stage biotechnology company dedicated to the discovery, development, and commercialization of innovative therapies to address underserved medical needs in oncology, autoimmune, and other severe diseases both in China and globally.

Leads Biolabs is a front-runner in next-generation immuno-oncology treatments with a differentiated pipeline of 14 innovative drug candidates, including four clinical-stage drug candidates and one registration-stage asset.

The Company adopts a science-driven R&D approach and has successfully established comprehensive R&D capabilities spanning antibody discovery and engineering, in vivo and in vitro efficacy evaluation, as well as druggability assessment. It has also developed multiple proprietary technology platforms, including LeadsBody (a CD3 T-cell engager platform), X-body (a 4-1BB engager platform), TOPiKinectics (an ADC platform) and ImBiTDC (a TDC platform), which serve as the cornerstone for its continued innovation and have been validated by the clinical outcomes of its bispecific antibody portfolios.

Leads Biolabs has established integrated capabilities across early discovery, translational medicine, clinical development, CMC and business development. The innovative nature and competitive strengths of its drug candidates, coupled with its global perspectives, proactive strategy, and efficient clinical validation, have made it an attractive partner for leading industry players and investment institutions. For more information, please visit https://en.leadsbiolabs.com/

SOURCE Nanjing Leads Biolabs Co., Ltd.