Stopping anti-HER2 treatment in patients with HER2-positive metastatic breast cancer
The STOP-HER2 Trial: a Phase 2 Study of Stopping Trastuzumab - Outcomes in Patients with HER2+ Metastatic Breast Cancer
This study is testing if people with HER2-positive metastatic breast cancer who have done well on treatment for three years can safely stop their anti-HER2 medication without their cancer getting worse.
Quick facts
| Phase | Phase 2 |
|---|---|
| Study type | Interventional |
| Enrollment | 82 (estimated) |
| Ages | 18 Years and up |
| Sex | All |
| Sponsor | Dana-Farber Cancer Institute Academic / other |
| Drugs / interventions | radiation |
| Locations | 13 sites (Phoenix, Arizona and 12 other locations) |
| Trial ID | NCT05721248 on ClinicalTrials.gov |
What this trial studies
This phase II study investigates whether patients with HER2-positive metastatic breast cancer, who have maintained exceptional response to anti-HER2 treatment for three years or more, can safely stop their treatment. The study includes two cohorts: one group will continue treatment while the other will cease it. Researchers will analyze blood samples for circulating tumor DNA (ctDNA) to identify which patients can stop treatment without disease progression. Participants will undergo periodic visits for blood work, questionnaires, and body scans over the course of the study.
Who should consider this trial
Good fit: Ideal candidates are adults aged 18 and older with HER2-positive metastatic breast cancer who have been on first-line anti-HER2 therapy for at least three years without disease progression.
Not a fit: Patients with progressive disease or those who have not achieved a stable response to anti-HER2 treatment will not benefit from this study.
Why it matters
Potential benefit: If successful, this study could allow certain patients to safely discontinue anti-HER2 treatment, reducing treatment burden and potential side effects.
How similar studies have performed: While this approach is novel in the context of stopping anti-HER2 treatment, similar studies have explored treatment cessation in other cancer types with varying degrees of success.
Eligibility criteria
Show full inclusion / exclusion criteria
Inclusion Criteria: * Age ≥18 years * Participants must have histologically or cytologically confirmed unresectable locally advanced or metastatic invasive breast carcinoma that is HER2-positive by American Society of Clinical Oncology/College of American Pathologists 2018 criteria, as assessed by standard institutional guidelines (central testing is not required). Both estrogen receptor (ER)-positive/HER2-positive and ER-negative/HER2-positive will be eligible. * Participants with ER-positive disease should continue endocrine therapy. * Participants must be currently receiving first-line anti-HER2 therapy (any regimen) for metastatic disease and must have been on this therapy for at least 3 years without evidence of progressive disease according to RECIST 1.1 criteria. The following exceptions apply: * Patients with history of brain-only progressive disease previously treated with local therapy (surgery and/or radiation therapy) are eligible, provided they meet all the following study criteria: * Asymptomatic * Not requiring anti-convulsant for symptomatic control * Not requiring corticosteroids * No evidence of interim central nervous system (CNS) progression between the completion of CNS-directed therapy and screening radiographic study * Minimum of 2 years (24 months) between completion of CNS-directed therapy and study start * Participants with history of oligo-progression (i.e., progressive disease of a single lesion) outside CNS treated with local treatment and/or change of endocrine therapy only are eligible, provided they meet the following criteria: * No evidence of interval progression between completion of local treatment or endocrine therapy change and screening radiographic study * Minimum 2 years (24 months) between completion of local therapy or treatment switch and study start * CT scan within 30 days of study start without definite evidence of progressive disease in the opinion of the treating investigator. * Available, representative archival formalin-fixed paraffin-embedded (FFPE) tumor tissue block from primary and/or metastatic site. If tissue block is unavailable, 20 unstained 10uM slides will be accepted (less than 20 slides may be acceptable with documentation of Sponsor-Investigator approval and would not require an eligibility exception). Tumor tissue must be received by coordinating site prior to study enrollment. * ECOG performance status 0-1 * For intervention arm only (cohort 2): willingness to stop anti-HER2 systemic therapy * Willingness and ability to comply with scheduled visits, treatment plan, laboratory tests, and other study procedures * Ability to understand the study requirements and document informed consent indicating awareness of the investigational nature and the risks of this study * Participants with another prior or concurrent malignancy whose natural history or treatment does not have the potential to interfere with the safety or efficacy assessment of this trial are eligible Exclusion Criteria: * Participants who are receiving any investigational agents to treat breast cancer * Participants with psychiatric illness/social situations that would limit compliance with study requirements. * All English- speaking patients will participate in the PRO measures. Patients that do not read or understand English are eligible to participate but will be exempt from the patient completed questionnaires
Where this trial is running
Phoenix, Arizona and 12 other locations
- Mayo Clinic Hospital Arizona — Phoenix, Arizona, United States (Recruiting)
- Georgetown University Medical Center — Washington, District of Columbia, United States (Recruiting)
- Mayo Clinical Hospital Florida — Jacksonville, Florida, United States (Recruiting)
- Dana-Farber Cancer Insitute — Boston, Massachusetts, United States (Recruiting)
- DFCI @ Foxborough — Foxborough, Massachusetts, United States (Recruiting)
- DFCI @ Merrimack Valley — Methuen, Massachusetts, United States (Recruiting)
- DFCI @ Milford Regional Hospital — Milford, Massachusetts, United States (Recruiting)
- DFCI @ South Shore Hospital — South Weymouth, Massachusetts, United States (Recruiting)
- Mayo Clinic Rochester — Rochester, Minnesota, United States (Recruiting)
- Duke University — Durham, North Carolina, United States (Recruiting)
- University of Pittsburgh Medical Center — Pittsburgh, Pennsylvania, United States (Recruiting)
- Baylor College of Medicine — Houston, Texas, United States (Recruiting)
- Fred Hutchinson Cancer Center — Seattle, Washington, United States (Recruiting)
Study contacts
- Principal investigator: Heather A Parsons, MD, MPH — Dana-Farber Cancer Institute
- Study coordinator: Heather A Parsons, MD, MPH
- Email: Heather_parsons@dfci.harvard.edu
- Phone: (617) 632-3800
How to participate
- Review the eligibility criteria above with your treating physician.
- Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
- Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.