China’s NMPA accepted the NDA for opamtistomig (LBL-024), a PD-L1/4-1BB bispecific antibody, for previously treated advanced extrapulmonary neuroendocrine carcinoma. The CDE granted priority review and the submission is supported by a registrational study of 96 patients across 34 sites. The filing highlights 4-1BB agonism as a continued immuno-oncology lever beyond PD-1/PD-L1 blockade, and it places a category-first mechanism—4-1BB-targeting bispecifics—on a defined regulatory path in China.