Transcenta Holding Limited (Stock Code: 6628) announced updated efficacy findings from the Phase I/II Transtar102 trial evaluating osemitamab plus nivolumab and CAPOX in first-line Gastric/Gastroesophageal Junction (G/GEJ) cancer. These results were presented at the ESMO Asia Congress 2025 in Singapore.

Data indicated that among 26 patients with CLDN18.2 expression of at least 40% and known PD-L1 combined positive scores, the therapy demonstrated a median progression-free survival of 16.6 months, an overall response rate of 68%, and a median duration of response of 18 months at a median follow-up of 25.8 months. Notably, the study observed a consistent treatment benefit regardless of PD-L1 expression level in patients with higher CLDN18.2 expression.

The safety profile of the combination remained consistent with earlier data, showing it was safe and well tolerated. Principal investigators highlighted the encouraging clinical signals, emphasizing how the regimen may potentially benefit a broad population of patients with advanced G/GEJ cancer.

Osemitamab is described as a high-affinity humanized anti-CLDN18.2 monoclonal antibody with enhanced antibody-dependent cellular cytotoxicity. It has been granted Orphan Drug Designation in the U.S. for patients with gastric, gastroesophageal junction, and pancreatic cancer.