AstraZeneca, Daiichi announces results from DESTINY-Gastric04 phase 3 trial

Positive results from the DESTINY-Gastric04 phase 3 trial showed ENHERTU demonstrated a statistically significant and clinically meaningful improvement in overall survival, OS, compared to ramucirumab plus paclitaxel in patients with second-line HER2 positive unresectable and/or metastatic gastric or gastroesophageal junction, GEJ, adenocarcinoma. ENHERTU is a specifically engineered HER2 directed DXd antibody drug conjugate, ADC, discovered by Daiichi Sankyo and being jointly developed and commercialized by Daiichi Sankyo and AstraZeneca (AZN). In the primary endpoint analysis of OS, ENHERTU reduced the risk of death by 30% versus ramucirumab plus paclitaxel. Median OS was 14.7 months with ENHERTU versus 11.4 months with ramucirumab plus paclitaxel. In the secondary endpoint analysis of progression-free survival, ENHERTU demonstrated a 26% reduction in the risk of disease progression or death versus ramucirumab plus paclitaxel as assessed by investigator. Median PFS was 6.7 months with ENHERTU versus 5.6 months with ramucirumab plus paclitaxel. A confirmed objective response rate of 44.3% was seen in patients treated with ENHERTU with seven complete responses and 97 partial responses versus an ORR of 29.1% with three CRs and 66 PRs in the ramucirumab plus paclitaxel arm. Median duration of response was 7.4 months in the ENHERTU arm and 5.3 months in the ramucirumab plus paclitaxel arm. Disease control rate was 91.9% with ENHERTU versus 75.9% with ramucirumab plus paclitaxel. Improvements in OS and PFS with ENHERTU were consistent across subgroups