Stage I HER2 Positive Invasive Breast Cancer De-escalation Study(IRIS) (IRIS)

August 17, 2026 updated by: Zhimin Shao, Fudan University

An Open-label,Phase II Study Evaluating the Efficacy and Safety of Trastuzumab Combined With Oral Chemotherapy or Endocrine Therapy in Patients With HER-2 Positive Stage I Breast Cancer

This is an open label, phase II study evaluating the efficacy and safety of trastuzumab combined with oral chemotherapy or endocrine therapy in patients with HER-2 positive stage I breast cancer.

Study Overview

Status

Active, not recruiting

Conditions

Detailed Description

This study has two cohorts. In Cohort A, patients who met the inclusion criteria(ER,PR<10%, T≤2cm or ER,PR ≥10% 1cm<T≤2cm)would be given capecitabine for 6 cycles with standard trastuzumab for 1 year, in which HR+ patients would be given endocrine therapy for 5 years. In Cohort B, patients who met the inclusion criteria(ER,PR ≥10% T≤1cm) would be given endocrine therapy (premenopausal: tamoxifen or toremifene; postmenopausal: letrozole or anastrozole or exemestane) combined with standard trastuzumab for 1 year and complete endocrine therapy for 5 years.

Study Type

Interventional

Enrollment (Actual)

367

Phase

  • Phase 2

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

    • Shanghai Municipality
      • Shanghai, Shanghai Municipality, China, 200032
        • Breast cancer institute of Fudan University Cancer Hospital

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years to 70 years (Adult, Older Adult)

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Females 18-70 years old;
  • Pathological confirmed of stage I breast cancer: histologically confirmed that the longest diameter of invasive cancer is no more than 2cm and the lymph node is negative (N0);
  • In IRIS-A cohort, if a patient is HR negative(ER/PR<10%), the longest diameter of invasive cancer could not exceed 2cm; while if a patient is HR positive(ER and/or PR ≥10%),the longest diameter of invasive cancer is greater than 1cm and no more than 2cm;
  • In IRIS-B cohort, a patient need to be HR positive (ER and / or PR expression ≥10%) and the longest diameter of invasive cancer could not exceed 1cm;
  • The pathological type of immunohistochemistry must meet the following conditions: HER-2 (3+) or HER-2 (0-2 +) with FISH detection is amplified;
  • For patients with invasive lesions on both sides, if both lesions are HER-2 positive and meet the tumor size requirements, then can be enrolled;
  • Has adequate organ function meeting the following criteria: (1) adequate bone marrow function: hemoglobin ≥ 90 g/L (no blood transfusion within 14 days); absolute neutrophil count ≥ 1.5 x 109 /L; platelet count ≥ 100 * 109 /L; (2)adequate liver and kidney function: Alanine Aminotransferase (ALT) ≤ 3×upper limit of normal (ULN), Aspartate Aminotransferase (AST) ≤ 3×ULN, Total Bilirubin (TBIL)≤ 1.5×ULN, serum creatinine ≤ 1×ULN#and with endogenous creatinine clearance rate of >50 ml/min (Cockcroft-Gault formula);
  • LVEF>50%;
  • The patient voluntarily joined the study, signed the informed consent form, had good compliance, and cooperated with the follow-up.

Exclusion Criteria:

  • Has received neoadjuvant therapy (include chemotherapy, targeted therapy, radiotherapy or endocrine therapy;
  • Has previous history of additional malignancy, with the exception of adequately treated basal cell carcinoma and cervical carcinoma in situ;
  • Has metastic (Stage 4) breast cancer;
  • Pregnant or breast feeding women, or women of childbearing age who cannot practice effective contraceptives;
  • Patients participating in other clinical trials at the same time;
  • Has severe organ dysfunction (cardiopulmonary liver and kidney) insufficiency, left ventricular ejection fraction (LVEF) < 50% (cardiac ultrasound); severe cardio cerebral vascular disease within the 6 months previous of randomization (such as unstable angina, chronic heart failure, uncontrolled hypertension with blood pressure>150/90mmHg, myocardial infarction, or cerebral blood vessel); diabetic patients with poor blood glucose control; patients with severe hypertension;
  • Has severe or uncontrolled infection;
  • Has a history of psychotropic substance abuse and were unable to abandon drug habits, or those with history of mental disorders;
  • The researchers considered patients to be unsuitable for the study.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Non-Randomized
  • Interventional Model: Single Group Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: IRIS-A
In IRIS-A cohort, patients who met the inclusion criteria(ER,PR<10%, T≤2cm or ER,PR ≥10% 1cm
Experimental: IRIS-B
In IRIS-B cohort, patients who met the inclusion criteria(ER,PR ≥10% T≤1cm) would be given endocrine therapy (premenopausal: tamoxifen or toremifene; postmenopausal: letrozole or anastrozole or exemestane) combined with standard trastuzumab for 1 year and complete endocrine therapy for 5 years.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
iDFS
Time Frame: 5 years
invasive disease-free survival
5 years

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
OS
Time Frame: 5 years
overall survival
5 years
DDFS
Time Frame: 5 years
distant disease-free survival,
5 years

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

May 20, 2020

Primary Completion (Estimated)

July 6, 2031

Study Completion (Estimated)

July 6, 2031

Study Registration Dates

First Submitted

May 7, 2020

First Submitted That Met QC Criteria

May 7, 2020

First Posted (Actual)

May 12, 2020

Study Record Updates

Last Update Posted (Actual)

August 19, 2026

Last Update Submitted That Met QC Criteria

August 17, 2026

Last Verified

August 1, 2026

More Information

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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