NCT06876714ClinicalTrials.gov
ShortStop-HER2: 12 Months vs. 6 Months of HER2-targeted Medications for People With HER2+ Breast Cancer Who Had a Pathologic Complete Response After Chemotherapy Plus Trastuzumab
ShortStop-HER2: Shortened Duration of Adjuvant Therapy in Patients With Early-Stage HER2+ Breast Cancer Who Achieve pCR After Neoadjuvant Chemotherapy With HER2 Blockade
In brief
This phase III trial compares 6 months of human epidermal growth factor receptor 2 (HER2)-targeted therapy to 12 months of HER2-targeted therapy for the treatment of HER2-positive (+) breast cancer in patients that had a pathologic complete response (pCR) after…
Phase 31,524 participants sought690 sites2 countries
Categories
Registered in 1 registry
- ClinicalTrials.govNCT06876714Open this record at ClinicalTrials.govSynced 2 weeks ago
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Trial information is shown as published by the registry, in its original language.
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How this study is set up
The points below are drawn from the public registry record for this study. Each one cites the field or sentence it came from. A dash (—) means the record does not state something — not that it is missing or wrong. Many well-run studies, especially small ones, leave some of these blank.
- Present: Registered before enrolment beganFirst posted 2025-03-14; recorded start 2025-09-17
- Present: Has a defined primary outcomeA primary outcome measure is listed in the record
- Present: The primary outcome states a time frameThe primary outcome measure records a time frame
- Present: Participants are randomly assignedAllocation is recorded as randomised
- Present: Has a comparison groupThe record lists a placebo or comparator arm, or more than one study arm
- Not stated: Open label (no blinding)Masking is recorded as none (open label)
- Not stated: An ethics committee is not stated in the registry recordThis registry's ingested record has no ethics-committee field
- Not stated: Regulatory oversight (such as an IND or IDE) is not stated in the registry recordThis registry's ingested record has no regulatory-authorisation field
- Not stated: A data monitoring committee is not stated in the registry recordThis registry's ingested record has no data-monitoring-committee fieldA data monitoring committee is not required for many smaller studies, and its absence here is not unusual.
- Present: No cost to participants is mentioned in the recordChecked the summary, description and eligibility text; no cost-to-participant phrase found
- Present: Sponsor has 95 other studies in this databaseCounted from the lead sponsor named in the record (Alliance for Clinical Trials in Oncology)
- Present: Sponsor has posted results for at least one studyBased on the sponsor’s studies in this database
- The record lists 3 conditions.
- Lead sponsor type recorded as: other.
- Intervention regulatory context: investigational, within a phased regulatory pathway.
Trial stature
Three independent measures of this study, described from its registry record — not a recommendation about it. A rigorous study by investigators nobody has heard of is better evidence than a weak study led by a famous one. How these are scored.
A strong methodological design for a phase 3 study, judged from its ClinicalTrials.gov record.
How this score is built
- Randomised allocation20/20
Participants are randomly allocated between arms
- Blinding0/20
Open-label
- Control arm15/15
Active-comparator control arm
- Primary-outcome specificity10/10
Named primary outcome with a defined time frame
- Endpoint type10/10
Mortality / MACE endpoint (hard clinical outcome)
- Multi-centre8/8
Multi-centre: 671 sites
- Data monitoring committee0/7
No data monitoring committee stated
- Prospective registration5/5
Registered before the study start date
- Protocol / SAP posted0/5
No protocol or SAP posted to the registry
A large study, international in scope: 1,524 participants (target), run at 690 sites, across 2 countries.
How this score is built
- Enrolment32/40
1,524 participants (target)
- Site count25/25
671 sites
- Country count7/15
2 countries
- Planned duration10/10
Planned over about 140 months
- Sponsor scale7/10
Alliance for Clinical Trials in Oncology has led 96 trials in our corpus
We have no verifiable track record for the investigator named on this trial. That is common for early-career investigators and for records held outside ClinicalTrials.gov — it is not a negative signal.
How this score is built
- Investigator standing0/100
No investigator recorded in the registry for this trial
These describe the registry record only, and today we hold ClinicalTrials.gov data. Absent fields lower a score, and absence often reflects registration practice rather than study quality. A high-stature trial is not necessarily safer or a better choice for you — enrolling in a large definitive trial can mean a higher chance of receiving placebo, while a small early-phase study may be the only route to a new therapy.
Summary
This phase III trial compares 6 months of human epidermal growth factor receptor 2 (HER2)-targeted therapy to 12 months of HER2-targeted therapy for the treatment of HER2-positive (+) breast cancer in patients that had a pathologic complete response (pCR) after preoperative (neoadjuvant) chemotherapy with trastuzumab. Trastuzumab and pertuzumab are monoclonal antibodies and forms of targeted therapy that attach to a receptor protein called HER2. HER2 is found on some cancer cells. When trastuzumab or pertuzumab attach to HER2, the signals that tell the cells to grow are blocked and the tumor cell may be marked for destruction by the body's immune system. Giving 6 months of HER2-targeted therapy may work better than giving 12 months for the treatment of HER2+ breast cancer in patients that had a pCR after neoadjuvant chemotherapy with trastuzumab.
Conditions
- Anatomic Stage I Breast Cancer AJCC v8
- Anatomic Stage II Breast Cancer AJCC v8
- Early Stage HER2+ Breast Cancer
Eligibility
| Sex | All |
|---|---|
| Ages | 18 Years – No maximum |
| Healthy volunteers | No |
Eligibility as written in the registry
Eligibility in plain statements
This record's criteria have not been broken into separate statements yet. The registry text above is complete and is the authoritative version.
Study design
| Study type | Interventional |
|---|---|
| Phase | Phase 3 |
| Allocation | Randomised |
| Intervention model | PARALLEL |
| Primary purpose | TREATMENT |
| Masking | NONE (0) |
| Enrolment | 1,524 participants sought |
Sponsor and collaborators
- Alliance for Clinical Trials in Oncology Sponsor
- National Cancer Institute (NCI) Collaborators
Arms and interventions
- Arm 1 (12-month adjuvant therapy)ACTIVE_COMPARATOR
Patients receive trastuzumab IV or trastuzumab/hyaluronidase-oysk SC on day 1 of each cycle. Patients may also receive pertuzumab IV or hyaluronidase-zzxf/pertuzumab/trastuzumab SC, at the discretion of the treating investigator, on day 1 of each cycle. Cycles repeat every 21 days for up to 17 cycles in the absence of disease progression or unacceptable toxicity. Patients also undergo ECHO or MUGA as well as mammography, ultrasound, or MRI throughout the trial. Patients may also optionally undergo blood and tissue sample collection throughout the trial.
- Arm 2 (6-month adjuvant therapy)EXPERIMENTAL
Patients receive trastuzumab IV or trastuzumab/hyaluronidase-oysk SC on day 1 of each cycle. Patients may also receive pertuzumab IV or hyaluronidase-zzxf/pertuzumab/trastuzumab SC, at the discretion of the treating investigator, on day 1 of each cycle. Cycles repeat every 21 days for up to 9 cycles in the absence of disease progression or unacceptable toxicity. Patients also undergo ECHO or MUGA as well as mammography, ultrasound, or MRI throughout the trial. Patients may also optionally undergo blood and tissue sample collection throughout the trial.
Interventions
- Procedure Biospecimen Collection
Undergo blood and tissue sample collection
- Procedure Echocardiography
Undergo ECHO
- Procedure Magnetic Resonance Imaging
Undergo MRI
- Procedure Mammography
Undergo mammography
- Procedure Multigated Acquisition Scan
Undergo MUGA
- Biological Pertuzumab
Given IV or SC
- Other Questionnaire Administration
Ancillary studies
- Biological Trastuzumab (Herceptin)
Given IV or SC
- Procedure Ultrasound
Undergo ultrasound
Outcome measures
Primary outcome
Recurrence-free survival (RFS)
The Kaplan-Meier method will be used to estimate the distribution of RFS times and a stratified log-rank test for non-inferiority will be used to assess whether RFS with 6 total months of human epidermal growth factor receptor 2 (HER2)-blockade is non-inferior to standard-of-care 12 total months of HER2-blockade in this patient population. Stratified Cox modeling will be used to estimate the hazard ratio and corresponding one-sided 95% confidence interval (CI).
Time frame From randomization to invasive local, regional or distant breast cancer recurrence, or death from any cause prior to a documented disease recurrence, assessed up to 10 years
Primary outcome
Functional Assessment of Cancer Therapy-Breast (FACT-B) total score (Quality of life)
Will compare the FACT-B total score between patients randomized to receive 6 months versus 12 months of combined neoadjuvant/adjuvant HER2 blockade. All questionnaires will be scored according to published scoring algorithms, including recommendations for addressing missing items within a scale. An intention-to-treat (ITT) approach will be used for all analyses. All statistical tests will be 2-sided, and p-values \< 0.05 will be considered statistically significant. To evaluate the between-arm mean difference in scores, a repeated measures mixed model will be estimated based on FACT-B total scores at all time points.
Time frame At 12 months
Secondary outcome
Incidence of grade 3 or higher adverse events (AE)
Will be according to the Common Terminology Criteria for Adverse Events version 5.0. The maximum grade of a specific AE experienced by a patient will be used. The proportion of patients who report a grade 3 or higher AE will be compared between the two treatment arms with a chi-square test. AEs (type and grade) for both arms will be summarized with the frequency and relative frequency
Time frame Baseline to 30 days after last dose of study treatment
Secondary outcome
Locoregional recurrence (LRR)
The cumulative incidence of LRR will be analyzed with Kaplan-Meier estimates (curve starting at 0 rather than 1) and compared with a stratified log rank test.
Time frame From randomization until invasive tumor recurs in the ipsilateral breast or chest wall, axillary, supraclavicular, or internal mammary nodes (if before or synchronous with a systemic recurrence), whichever comes first, assessed up to 10 years
Secondary outcome
Overall survival
Will be compared between the treatment arms with a stratified log rank test and a stratified Cox model will be used to generate the hazard ratio estimate (both a point estimate and 95% CI). The analyses will be done as ITT groups as well as per-protocol groups.
Time frame From randomization until death due to any cause, assessed up to 10 years
Secondary outcome
RFS for key subgroups
Forest plots will be generated for key prognostic variables (including the stratification variables) and subgroups of interest to determine whether the treatment effect appears homogeneous across the subgroups for the ITT population. Additional key subgroups of interest are neoadjuvant chemotherapy backbone and the type of adjuvant HER2-blockade the patient actually received (dual versus single). With respect to the latter analysis, the interest will be in whether there is an apparent difference in treatment effect among patients who received adjuvant pertuzumab versus those who did not.
Time frame From randomization to invasive local, regional or distant breast cancer recurrence, or death from any cause prior to a documented disease recurrence, assessed up to 10 years
Secondary outcome
Time to central nervous system (CNS) recurrence
Will assess both isolated CNS recurrence as first events, and CNS recurrence events simultaneous with distant metastasis and/or LRR.
Time frame up to 10 years
Secondary outcome
FACT-B total score (Quality of life)
Will compare the FACT-B total score between patients randomized to receive 6 months versus 12 months of combined neo/adjuvant HER2 blockade. All questionnaires will be scored according to published scoring algorithms, including recommendations for addressing missing items within a scale. An ITT approach will be used for all analyses. All statistical tests will be 2-sided, and p-values \<0.05 will be considered statistically significant. To evaluate the between-arm mean difference in scores, a repeated measures mixed model will be estimated based on FACT-B total scores at all time points.
Time frame At 18 months
Secondary outcome
Side effect bother (Quality of life)
Will be assessed by Functional Assessment of Cancer Therapy General Population 5 between patients randomized to receive 6 months versus 12 months of combined neo/adjuvant HER2 blockade. All questionnaires will be scored according to published scoring algorithms, including recommendations for addressing missing items within a scale. An ITT approach will be used for all analyses. All statistical tests will be 2-sided, and p-values \<0.05 will be considered statistically significant. To evaluate the between-arm mean difference in scores, a repeated measures mixed model will be estimated based on scores. Mean trajectories over time will be plotted by arm.
Time frame At 6 or 12 months
Secondary outcome
Patient reported symptomatic AE (Quality of life)
Will be measured by Patient Reported Outcomes-Common Terminology Criteria for Adverse Events (PRO-CTCAE). Will assess symptomatic AE using PRO-CTCAE measures for symptoms of interest, specifically diarrhea, constipation, fatigue, and rash. The proportion of patients with a maximum post-baseline score greater than 0 will be compared between arms using Fisher's exact test. For diarrhea, constipation, and fatigue, the proportion of patients with a maximum post-baseline score greater than or equal to 3 will be compared between arms using Fisher's exact test.
Time frame At 6 or 12 months
Dates
| Start date | September 17, 2025 (actual) |
|---|---|
| Primary completion | March 13, 2028 (estimated) |
| Completion | March 13, 2037 (estimated) |
| First posted | March 14, 2025 (actual) |
| Last updated | September 2, 2026 |
| Results posted | Not stated in the registry record |
| Status last verified | September 2026 |
Actual means the event happened. Estimated means the sponsor expects it. The two mean different things.
Locations
600 sites are recruiting
Puerto Rico
| Facility | City | State or region | Status |
|---|---|---|---|
| Doctors Cancer Center | Manati | Recruiting | |
| San Juan City Hospital | San Juan | Recruiting | |
| Centro Comprensivo de Cancer de UPR | San Juan | Recruiting | |
| PROncology | San Juan | Recruiting |
United States
| Facility | City | State or region | Status |
|---|---|---|---|
| UM Upper Chesapeake Hematology and Oncology - Aberdeen | Aberdeen | Maryland | Recruiting |
| Phoebe Putney Memorial Hospital | Albany | Georgia | Recruiting |
| University of New Mexico Cancer Center | Albuquerque | New Mexico | Recruiting |
| Presbyterian Kaseman Hospital | Albuquerque | New Mexico | Recruiting |
| Aultman Alliance Community Hospital | Alliance | Ohio | Suspended |
| OSF Saint Anthony's Health Center | Alton | Illinois | Suspended |
| McFarland Clinic - Ames | Ames | Iowa | Recruiting |
| Mary Greeley Medical Center | Ames | Iowa | Recruiting |
| Community Hospital of Anaconda | Anaconda | Montana | Recruiting |
| UI Health Care Mission Cancer and Blood - Ankeny Clinic | Ankeny | Iowa | Recruiting |
| University of Michigan Rogel Cancer Center | Ann Arbor | Michigan | Recruiting |
| Aspirus Cancer Care-Antigo-Volm Cancer Center | Antigo | Wisconsin | Recruiting |
| ThedaCare Regional Cancer Center | Appleton | Wisconsin | Recruiting |
| Mission Hope Medical Oncology - Arroyo Grande | Arroyo Grande | California | Suspended |
| Duluth Clinic Ashland | Ashland | Wisconsin | Recruiting |
| Emory University Hospital/Winship Cancer Institute | Atlanta | Georgia | Recruiting |
| Emory Saint Joseph's Hospital | Atlanta | Georgia | Recruiting |
| Northside Hospital | Atlanta | Georgia | Recruiting |
| Emory University Hospital Midtown | Atlanta | Georgia | Recruiting |
| Grady Health System | Atlanta | Georgia | Recruiting |
| Harold Alfond Center for Cancer Care | Augusta | Maine | Recruiting |
| Rush-Copley Medical Center | Aurora | Illinois | Suspended |
| UCHealth University of Colorado Hospital | Aurora | Colorado | Recruiting |
| IU Health West Hospital | Avon | Indiana | Recruiting |
| Mercy Oncology and Hematology - Clayton-Clarkson | Ballwin | Missouri | Recruiting |
| MedStar Franklin Square Medical Center/Weinberg Cancer Institute | Baltimore | Maryland | Recruiting |
| Greater Baltimore Medical Center | Baltimore | Maryland | Recruiting |
| University of Maryland/Greenebaum Cancer Center | Baltimore | Maryland | Recruiting |
| Sinai Hospital of Baltimore | Baltimore | Maryland | Recruiting |
| MedStar Good Samaritan Hospital | Baltimore | Maryland | Recruiting |
| CommonSpirit Saint Joseph Hospital - Bardstown | Bardstown | Kentucky | Suspended |
| Advocate Good Shepherd Hospital | Barrington | Illinois | Recruiting |
| Bronson Battle Creek | Battle Creek | Michigan | Recruiting |
| Houston Methodist San Jacinto Hospital | Baytown | Texas | Recruiting |
| Beaufort Memorial Hospital | Beaufort | South Carolina | Recruiting |
| UPMC-Heritage Valley Health System Beaver | Beaver | Pennsylvania | Recruiting |
| UM Upper Chesapeake Medical Center | Bel Air | Maryland | Recruiting |
| MedStar Health Bel Air Medical Campus | Bel Air | Maryland | Recruiting |
| Nebraska Medicine-Bellevue | Bellevue | Nebraska | Recruiting |
| Sanford Joe Lueken Cancer Center | Bemidji | Minnesota | Recruiting |
| Saint Charles Health System | Bend | Oregon | Recruiting |
| Central Vermont Medical Center/National Life Cancer Treatment | Berlin Corners | Vermont | Recruiting |
| Walter Reed National Military Medical Center | Bethesda | Maryland | Recruiting |
| Tower Cancer Research Foundation | Beverly Hills | California | Recruiting |
| Billings Clinic Cancer Center | Billings | Montana | Recruiting |
| Sanford Bismarck Medical Center | Bismarck | North Dakota | Recruiting |
640 further sites are listed in the registry record.
Study documents
No documents are linked in this registry record.
Changes over time
- September 2, 2026
Site added
6 sites added (690 total)
684690
- August 5, 2026
Site added
13 sites added (684 total)
671684