Zhitong Finance App News, Weilizhibo-B (09887) announced that the company's core product, Velisin® (opatisumimab, PD-L1/4-1BB bispecific antibody), has been certified by the US Food and Drug Administration (FDA) for first-line treatment of advanced biliary tract cancer (BTC). This is the second FDA Fast Track qualification for Velisign® after extrapulmonary neuroendocrine carcinoma (EP-NEC). Based on impressive data from Velisign® in first-line BTC clinical studies, it only took 9 days from submission to approval. The FDA also recommended that the company communicate about the registration plan for Velisign® combination chemotherapy on BTC as soon as possible. The certification is expected to accelerate the development, registration and commercialization of Velisign® in the US for treating BTC.
Fast Track Accreditation aims to accelerate the development and review process of drugs and biological products that treat serious or life-threatening diseases and have the potential to address unmet medical needs. After receiving this certification, Verisign® will enjoy a range of policy support, including but not limited to: (i) the company may receive more frequent regulatory interaction from the FDA and receive customized guidance on key matters (including clinical trial design and data requirements) to help optimize the R&D path; and (ii) when relevant eligibility criteria are met, the listing application can be reviewed on a rolling basis, allowing the completed portion to be submitted for review before the entire application is finalized, which may shorten the overall review time.
Velisign® conditionally activates 4-1BB to amplify T cells. Its differentiating advantage is that it may overcome the limited benefits of immunotherapy for “cold tumors” and bring long-lasting survival benefits. The company initiated its first single-drug terminal phase i/IIa basket trial in 2022, and a total of 175 patients were enrolled. The trial assessed the performance of Velisign® in various cold tumor indications such as BTC, platinum-resistant ovarian cancer, PD-1 drug-resistant terminal hepatocellular carcinoma (HCC), and terminal EP-NEC, and all showed a significantly longer survival benefit trend compared to historical data. The relevant data is expected to be published in authoritative international journals.
Based on this, Velisign® rapidly progressed from early backline exploration to frontline clinical development, and continued to make progress in regulatory certification. Currently, clinical research on the first-line treatment of BTC with Velisign® is progressing efficiently and in an orderly manner. In April 2026, based on good safety characteristics and efficacy data, the company successfully advanced the first-line phase II clinical study of advanced BTC to the expansion stage, and completed the enrollment of all patients thereafter, demonstrating the breakthrough potential of this drug in immunizing “cold tumors.” This Fast Track qualification further clarifies the project's anticipated registration path in the US.