CSTONE PHARMA-B (02616) saw its gains expand beyond 20%. At the time of writing, the stock was up 19.42% to HK$8.24, with a turnover of HK$377 million. The surge follows the company's announcement of the latest clinical progress for its self-developed PD-1/VEGF/CTLA-4 trispecific antibody, CS2009. Preliminary efficacy data from Phase I/II trials of CS2009 as a monotherapy for lung cancer showed promising results. Among first-line non-small cell lung cancer (NSCLC) patients with a PD-L1 tumor proportion score (TPS) of 50% or higher, the objective response rate (ORR) reached 90%, with a disease control rate (DCR) of 100%. In immunotherapy (IO) pretreated, driver gene-negative second-line and later-line NSCLC patients, the ORR was 25%. Based on these outcomes, CSTONE PHARMA-B plans to initiate the first set of Phase III global multicenter clinical trials (MRCT) for CS2009 by the end of 2026, focusing on indications such as NSCLC, colorectal cancer (CRC), and small cell lung cancer (SCLC). Additional Phase I and II clinical research data for CS2009 are expected to be presented in 2026 at the American Society of Clinical Oncology (ASCO) annual meeting and/or the European Society for Medical Oncology (ESMO) congress.