Phase 2 study of trastuzumab deruxtecan for HER2-postive advanced G/GEJ cancer on or after trastuzumab in Western patients

Approximately 15-20% of advanced gastric and gastro-esophageal junction (G/GEJ) cancers overexpress HER2. DESTINY-Gastric01, in Japan and South Korea, showed that trastuzumab deruxtecan (T-DXd) improved response and overall survival versus chemotherapy in patients with HER2-positive advanced G/GEJ cancer whose disease progressed after two lines of previous therapy including trastuzumab. The phase 2 DESTINY-Gastric02 study evaluated T-DXd for HER2-positive advanced G/GEJ cancer in patients living in Europe or the USA, with progression after a trastuzumab-containing regimen. At median 10.2 months follow-up, complete response was seen in 5% of patients and partial response in 37%. Drug-related serious adverse events occurred in 13%, with grade 5 events in 3%. The authors conclude that these results support the use of T-DXd as second-line therapy in patients with HER2-positive advanced G/GEJ cancer.