Transcenta has completed enrolment of first-line CLDN18.2 expressing Gastric / Gastro-esophageal Junction (G/GEJ) adenocarcinoma patients in cohorts C and G of its China Phase II trial (Transtar-102) of Osemitamab (TST001).

The ongoing multi-cohort, multi-centre Phase I/II open-label study is designed to assess the safety, tolerability and efficacy of Osemitamab.

Osemitamab is a high affinity humanised ADCC-enhanced anti-CLDN18.2 monoclonal antibody with enhanced anti-tumour activities.

The trial will evaluate Osemitamab as single agent or in combination in various indications.

Osemitamab at the dose of 3 or 6mg/kg once every 3 weeks (Q3W) in combination with Nivolumab plus Capecitabine and Oxaliplatin (CAPOX) will be evaluated in a total of 82 patients of cohort G.

Cohort C is evaluating Osemitamab in combination with CAPOX.

Preliminary data demonstrated the absence of unexpected safety findings and efficacy as immature.

Transcenta Global Medicine Development executive vice-president and chief medical officer Dr Caroline Germa said: “These clinical data lay the foundation of our Phase III and comply with dose optimisation requirements from Health Authorities.

“They also provide important information related to the predictive role of CLDN18.2 expression on Osemitamab (TST001) associated outcomes, particularly in the medium and low expressors.

“We look forward to releasing these data in the very near future.”