CSTONE PHARMA-B (02616.HK): CS2009 Data in 300+ Patients at ESMO; 100% ORR in 1L NSCLC Cohort

NewTimeSpace News: On 25 October 2026, CStone Pharmaceuticals (stock code: 2616) announced that its independently developed PD-1/VEGF/CTLA-4 trispecific antibody CS2009 was presented in two rapid oral presentations at the 2026 ESMO Congress, with data from more than 300 patients completing proof of mechanism, proof of safety and proof of concept simultaneously.

In first-line non-small cell lung cancer (NSCLC), among patients with PD-L1 TPS≥50%, the 30 mg/kg monotherapy cohort achieved an objective response rate (ORR) and disease control rate (DCR) of 100% (11/11), while the 20 mg/kg cohort had an ORR of 76.9%; the overall TPS≥50% population had an ORR of 87.5% (21/24). In heavily pretreated NSCLC, where 84.2% had prior immunotherapy, 30 mg/kg monotherapy produced an ORR of 28.0%, a DCR of 60.0% and a median duration of response of 10.5 months; combined with docetaxel in second/third-line patients, the ORR was 55.6% and the DCR 100%. In first-line squamous NSCLC combined with paclitaxel and carboplatin, the 30 mg/kg cohort achieved an ORR of 85.7% and a DCR of 100%, with an overall ORR of 81.5% (22/27).

In colorectal cancer, first-line pMMR/MSS metastatic CRC treated with CS2009 plus XELOX achieved an ORR of 63.6% (14/22) and a DCR of 100%, with an ORR of 68.8% in patients with liver metastases; in heavily pretreated patients, monotherapy produced an ORR of 20.0% (3/15) and a DCR of 93.3%.

On safety, grade 3 or above treatment-related adverse events occurred in 25.9% and 52.4% of the NSCLC monotherapy and combination cohorts respectively, with grade 3 or above immune-related adverse events in 11.6% and 12.7%; in the mCRC cohorts the rates were 13.0% and 21.7%, with no new safety signals identified. The Company plans to start a global multicentre registrational Phase III trial by the end of 2026 and is in discussions with several multinational pharmaceutical companies.