CLDN18 and gastric cancer: Randomized phase 2 (FAST, NCT01630083) and phase 3 trials (SPOTLIGHT, NCT03504397, and GLOW, NCT03653507) have demonstrated the clinical efficacy of zolbetuximab in combination with chemotherapy in patients with HER2-negative unresectable/recurrent gastric cancer showing high expression of CLDN18.2 [3–5].