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NCT05721248

The STOP-HER2 Trial: A Phase 2 Study of Stopping Trastuzumab - Outcomes in Patients With HER2+ Metastatic Breast Cancer

Active, enrolled Phase 2 Last updated 18 February 2026
What this trial tests

Phase 2 trial testing Cessation of anti-HER2 treatment in Breast Cancer in 82 participants. Participants enrolled and being followed up; not accepting new ones.

Timeline
19 April 2023
Primary endpoint
1 June 2026
1 June 2036

Quick facts

Lead sponsorDana-Farber Cancer Institute
PhasePhase 2
StatusActive, enrolled
Study typeINTERVENTIONAL
Allocationnon randomized
Designparallel
Maskingnone
Primary purposetreatment
Enrollment82
Start date19 April 2023
Primary completion1 June 2026
Estimated completion1 June 2036
Sites13 locations across United States

Drugs / interventions tested

Conditions studied

Sponsor

Dana-Farber Cancer Institute

Who can join

18 and older, any sex, with Breast Cancer or Metastatic Breast Cancer. Patients with the condition only — healthy volunteers not accepted.

What's being measured

Primary outcomes are the specific endpoints the trial is designed to prove or disprove.

Sponsor's own description

This study is being done to see if anti-HER2 treatment be safely stopped in patients with HER2-positive metastatic breast cancer (MBC) that have had exceptional response to treatment. Exceptional response" is considered as cancer progression being controlled for three years or more since starting anti-HER2 treatment.

Publications & conference data

4 peer-reviewed publications reference this trial (live from Europe PMC):

  1. Management of patients with advanced-stage HER2-positive breast cancer: current evidence and future perspectives.
    Marra A, Chandarlapaty S, Modi S. · · 2024 · cited 79× · PMID 38191924 · DOI 10.1038/s41571-023-00849-9
  2. Standard-of-Care Treatment for HER2+ Metastatic Breast Cancer and Emerging Therapeutic Options.
    Premji SK, O'Sullivan CC. · · 2024 · cited 9× · PMID 38410761 · DOI 10.1177/11782234241234418
  3. Clinico-pathological predictors of radiologic complete response to first-line anti-HER2 therapy in metastatic breast cancer.
    Cucciniello L, Blondeaux E, Bighin C, Gasparro S, et al · · 2024 · cited 3× · PMID 39695115 · DOI 10.1038/s41523-024-00713-8
  4. Real-World Evidence of Long-Term Disease Control in HER2-Positive Metastatic Breast Cancer Patients Treated with a First-Line Combination of Trastuzumab and/or Pertuzumab Plus Chemotherapy.
    Chaigneau L, Lapp E, Jai T, Dobi E, et al · · 2025 · PMID 41228325 · DOI 10.3390/cancers17213532

Verify or expand the search:

Other recruiting trials for Breast Cancer

Currently open trials in the same condition.

Other Dana-Farber Cancer Institute trials

Trials by the same sponsor.

Verify against primary sources

Data sources for this page

Drug Landscape aggregates and links these public records for informational use only. Always verify against the primary source before clinical or regulatory decisions. Canonical URL: https://druglandscape.com/trial/NCT05721248.

Primary sources · FDA · ClinicalTrials.gov · EMA · SEC EDGAR · ChEMBL · Wikidata · full sourcing