MedTrace Logo

DEWI: Watch-and-Wait With Dostarlimab in Localized dMMR/MSI-H Gastric/GEJ Adenocarcinoma Phase II Study

NCT06059495 · Status: RECRUITING · Phase: PHASE2 · Type: INTERVENTIONAL · Enrollment: 89

Last updated 2026-08-18

No results posted yet for this study

Summary

This phase II study evaluates dostarlimab followed by a watch-and-wait strategy in patients with localized dMMR/MSI-H gastric or gastroesophageal junction (GEJ) adenocarcinoma. The study aims to determine whether surgery can be safely avoided in patients achieving a complete response, defined by negative endoscopy and tumor-free biopsies after treatment.

Conditions

  • Adenocarcinoma - GEJ
  • Gastric Adenocarcinoma

Interventions

DRUG

Dostarlimab

Post-Inclusion: Dostarlimab 500mg IV q3wx4 cycles (Cs). Week 12 (W12) * cCR (both cohorts): Dostarlimab 1,000mg q6w×2 cycles. * Downstaging (Stage 2-3), no PD/mets: Dostarlimab 500mg q3w×4Cs. * Main cohort: SD/PD, Stage 1, positive(+), no cCR→Surgery. Post-surgery: Becker-TRG 1a/1b/2→Dostarlimab 1,000mg q6w×6Cs; Becker-TRG 3→Stop Trt. * Additional unfit cohort: SD/PD, Stage 1, biopsy(+) ± mets→Stop dostarlimab, withdraw from Trt, investigator-directed care, remain in FU. W24 * cCR at W12\&W24: Dostarlimab 1,000mg q6w×4Cs. * cCR at W12 but not W24: * Main cohort: Stop dostarlimab; surgery/adjuvant Trt per investigator. * Additional unfit cohort: Stop dostarlimab; withdraw from Trt; FU only. * Downstaging at W12 + cCR at W24: Dostarlimab 1,000mg q6w×4Cs. * Downstaging at W12 but no cCR at W24: * Main cohort: Surgery; if Becker-TRG 1a/1b/2, dostarlimab 1,000mg q6w×4Cs. * Additional unfit cohort: Stop dostarlimab, withdraw from Trt, investigator-directed care, remain in FU.

Sponsors & Collaborators

  • GERCOR - Multidisciplinary Oncology Cooperative Group

    lead OTHER

Principal Investigators

  • Thierry Andre, MD · Saint-Antoine Hospital

Study Design

Allocation
NA
Purpose
TREATMENT
Masking
NONE
Model
SINGLE_GROUP

Eligibility

Min Age
18 Years
Max Age
75 Years
Sex
ALL
Healthy Volunteers
No

Timeline & Regulatory

Start
2024-01-22
Primary Completion
2028-09-01
Completion
2028-09-01

Countries

  • France
  • Italy

Study Locations

More Related Trials

Read the full study record

This page highlights key information. For complete eligibility criteria, study locations, investigator contacts, and the full protocol, visit the original record on ClinicalTrials.gov.

View NCT06059495 on ClinicalTrials.gov