LEADS BIOLABS-B(09887): The Phase II clinical study of VeliXin (Opalizumab, a PD-L1/4-1BB bispecific antibody, LBL-024) as first-line treatment for ESCC has entered the expansion stage.

LEADS BIOLABS-B (09887) announced that the companys self-developed investigational drug, ViliXin (OpaItezumab, a PD-L1/4-1BB bispecific antibody, LBL-024), has successfully progressed to the expansion phase of its Phase II clinical study as a first-line treatment for locally advanced or metastatic esophageal squamous cell carcinoma (ESCC) after completing the safety lead-in phase. This advancement follows the observation of positive efficacy signals, along with good safety and tolerability. The study is led by Professor Shen Lin from Beijing Cancer Hospital. During the safety lead-in phase, ViliXin combined with chemotherapy showed positive efficacy signals in ESCC patients, with an overall good safety profile and tolerability. Based on a comprehensive assessment by the sponsor and investigators, the study has moved into the expansion phase for combination therapy. This expansion phase uses a randomized controlled design to compare the efficacy and safety of ViliXin combined with chemotherapy against the combination of Tislelizumab and chemotherapy as a first-line treatment for ESCC, aiming to further enhance the clinical benefit of existing standard treatments. ViliXin is currently being evaluated in 11 clinical studies, including one single-arm pivotal registration study, one confirmatory Phase III clinical study, and nine proof of concept (POC) studies. To date, three POC studies for first-line treatment of extrapulmonary neuroendocrine carcinoma (EP-NEC), small cell lung cancer (SCLC), and biliary tract cancer (BTC) have completed patient enrollment, with the first-line EP-NEC study having progressed to the confirmatory Phase III clinical stage. POC studies for hepatocellular carcinoma (HCC) and ESCC have successfully entered the expansion phase, continuing to validate ViliXin's potential for pan-tumor efficacy. Leveraging the conditional activation design of the company's proprietary X-body platform, ViliXin has demonstrated clear and durable efficacy signals across multiple indications. Clinical data from seven indications show significant clinical value and broad therapeutic potential. ViliXin has also maintained a good safety and tolerability profile in approximately 800 enrolled subjects, laying a solid foundation for its continued development as a next-generation cornerstone therapy in oncology. ViliXin is a bispecific antibody that targets both PD-L1 and 4-1BB, representing a potential life-extending pan-tumor IO2.0 cornerstone therapy. Developed using our independently developed X-body platform, ViliXin enables the conditional activation of 4-1BB while alleviating PD-1/PD-L1 immune suppression, thereby enhancing T cell activation regulated by 4-1BB to achieve a synergistic effect in eradicating tumors. ViliXin exhibits comparable safety to PD-1/PD-L1 inhibitors and greater broad-spectrum cancer treatment potential, having shown first-in-class (FIC) or best-in-class (BIC) potential in tumors like non-small cell lung cancer (NSCLC), small cell lung cancer (SCLC), extrapulmonary neuroendocrine carcinoma (EP-NEC), and biliary tract cancer (BTC). As the worlds first molecular targeting the co-stimulatory receptor 4-1BB that has entered the pivotal single-arm key registration clinical stage, ViliXin holds promise to become the first approved treatment for EP-NEC. ViliXin has initiated clinical studies for 13 solid tumor indications in China, including one pivotal registration clinical study and eight proof of concept studies, covering EP-NEC, NSCLC, SCLC, BTC, ovarian cancer (OC), esophageal squamous cell carcinoma (ESCC), liver cancer (HCC), gastric cancer (GC), triple-negative breast cancer (TNBC), malignant melanoma, and other areas with high unmet clinical needs. It is particularly noteworthy that activation of the 4-1BB co-stimulatory pathway can restore and enhance the activity of apoptotic T cells and promote their expansion, making therapies targeting 4-1BB potentially suitable for treating immunologically cold tumors that are resistant or ineffective to PD-1/PD-L1 inhibitors, and possessing the potential for durable survival benefits with prolonged tail effects. In October 2024, ViliXin received breakthrough therapy designation from the NMPA Center for Drug Evaluation, followed by orphan drug designation from the U.S. Food and Drug Administration (FDA) in November 2024. In January 2026, ViliXin was granted fast track designation by the FDA and orphan drug designation in the European Union.