Author:

Lin Shen¹, Dan Liu¹, Ning Li², Weijian Guo³, Tianshu Liu⁴, Lijuan Zhang⁵, Xuelian, Zhu⁵, Chuan Qi⁵, Xu Li⁵, Xueming Qian⁵, Caroline Germa⁵.
1. Peking University Cancer Hospital; 2. Henan Cancer Hospital; 3. Fudan University Cancer Center; 4. Fudan University Affiliated Zhongshan Hospital; 5. Suzhou Transcenta Therapeutics Co, Ltd.

Background:

• Phase 3 studies (SPOTLIGHT and GLOW) showed that combining anti-CLDN18.2 antibody with chemotherapy significantly improved PFS and OS as first-line treatment for G/GEJ (gastric/gastroesophageal junction) cancer with CLDN18.2 expression above 75%, 2/3+
per Astellas CDx (~38% of all G/GEJ cancer patients).
• TST001 (osemitamab) is a potential best-in-class antibody with improved CLDN18.2 affinity and enhanced ADCC effect, leading to anti-tumor activity in low to medium CLDN18.2 expression gastric cancer animal models.
• The preliminary efficacy of TST001 in combination with CAPOX in the patients with advanced G/GEJ cancer was reported previously in ASCO and ESMO-GI. Here we present the updated analysis in the patients from dose expansion phase who had received TST001 at 6mg/kg Q3W and CAPOX.

Conclusions:

• Phase 3 studies (SPOTLIGHT and GLOW) showed that combining anti-CLDN18.2 antibody with chemotherapy significantly improved PFS and OS as first-line treatment for G/GEJ (gastric/gastroesophageal junction) cancer with CLDN18.2 expression above 75%, 2/3+ per Astellas CDx (~38% of all G/GEJ cancer patients).
• TST001 (osemitamab) is a potential best-in-class antibody with improved CLDN18.2 affinity and enhanced ADCC effect, leading to anti-tumor activity in low to medium CLDN18.2 expression gastric cancer animal models.
• The preliminary efficacy of TST001 in combination with CAPOX in the patients with advanced G/GEJ cancer was reported previously in ASCO and ESMO-GI. Here we present the updated analysis in the patients from dose expansion phase who had received TST001 at 6mg/kg Q3W and CAPOX.