MATTERHORN — Perioperative Durvalumab plus FLOT in Resectable Gastric and Gastroesophageal Junction Cancer

Phase 3 · 2025 · Gastric Cancer, Gastroesophageal Junction Cancer

Design

Double-blind phase 3 randomizing 1:1 to durvalumab or placebo plus perioperative FLOT (2 neoadjuvant + 2 adjuvant cycles), followed by durvalumab or placebo maintenance.

Population

Resectable gastric or gastroesophageal junction adenocarcinoma.

Primary Endpoint

event-free survival (EFS)

Key Result

2-yr EFS 67.4% vs 58.5% with FLOT alone (HR 0.71); 2-yr OS 75.7% vs 70.4% with a higher pathological complete response rate.

Guideline Impact

Perioperative therapy for resectable gastric/GEJ cancer