Evaluating the Response-Guided Therapy With Neoadjuvant Endocrine Therapy to Optimize Adjuvant Treatment in Premenopausal HR+/HER2- Breast Cancer (JCOG2402, Young HOPE)
YoungHOPE
A Randomized Phase III Study of Response-Guided Therapy Following Neoadjuvant Endocrine Therapy to Optimize Adjuvant Treatment in Premenopausal HR+/HER2- Breast Cancer (JCOG2402, Young HOPE)
2 other identifiers
interventional
950
1 country
49
Brief Summary
Young HOPE/JCOG2402 is a multicenter, randomized phase III study designed to evaluate response-guided therapy following neoadjuvant endocrine therapy to optimize adjuvant treatment in premenopausal HR+/HER2- Breast Cancer. Premenopausal women with intermediate-risk HR-positive/HER2-negative breast cancer derive benefit from the addition of chemotherapy to endocrine therapy. However, previous studies have demonstrated that patients who achieve an endocrine response (Ki-67 ≤10%) following neoadjuvant endocrine therapy have excellent outcomes without chemotherapy, irrespective of menopausal status. These findings suggest that endocrine therapy response may serve as a predictive biomarker to identify premenopausal patients who can safely omit chemotherapy. The primary objective of this study is to evaluate the non-inferiority of an ET response-guided treatment strategy compared with standard surgery followed by adjuvant therapy. The study aims to increase the proportion of patients who can be treated with endocrine therapy alone by omitting chemotherapy in those with highly endocrine-sensitive disease. Eligible patients are randomized 1:1 to upfront surgery or neoadjuvant endocrine therapy with an aromatase inhibitor and ovarian function suppression. The primary endpoint is EFS. Secondary endpoints include overall survival, relapse-free survival, distant recurrrence-free survival, HR-QOL, the rate of endocrine therapy alone in adjuvant therapy, ET response rate in an Arm B, the rate of non-menopause and safety. A total of 950 patients will be enrolled. Randomization is stratified by cN0 vs cN1, HG1 or 2 vs 3, and institution. The JCOG2402 trial addresses an unmet need in adjuvant therapy of premenopausal HR-positive, HER2-negative breast cancer with intermediate risk and may contribute to the establishment of a new treatment strategy.
Trial Health
Trial Health Score
Automated assessment based on enrollment pace, timeline, and geographic reach
participants targeted
Target at P75+ for phase_3 breast-cancer
Started Jan 2026
Longer than P75 for phase_3 breast-cancer
49 active sites
Health score is calculated from publicly available data and should be used for screening purposes only.
Trial Relationships
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Study Timeline
Key milestones and dates
Study Start
First participant enrolled
January 28, 2026
CompletedFirst Submitted
Initial submission to the registry
June 22, 2026
CompletedFirst Posted
Study publicly available on registry
June 26, 2026
CompletedPrimary Completion
Last participant's last visit for primary outcome
January 27, 2038
ExpectedStudy Completion
Last participant's last visit for all outcomes
January 27, 2039
July 8, 2026
June 1, 2026
12 years
June 22, 2026
July 4, 2026
Conditions
Keywords
Outcome Measures
Primary Outcomes (1)
Event free survival
Time from randomization to the first diagnosis of local invasive recurrence, regional recurrence, distant recurrence, contralateral invasive breast cancer, inoperable progressive disease during neoadjuvant endocrine therapy, second primary invasive non-breast cancer (excluding non-melanoma skin cancer and in situ cervical cancer), or death from any cause
Up to 12 years (5 years of accrual and 7 years of follow-up)
Secondary Outcomes (3)
Overall survival
Up to 12 years (5 years of accrual and 7 years of follow-up)
Relapse-free survival
Up to 12 years (5 years of accrual and 7 years of follow-up)
Distant recurrence-free survival
Up to 12 years (5 years of accrual and 7 years of follow-up)
Study Arms (2)
Upfront surgery (Arm A)
ACTIVE COMPARATORParticipants in Arm A will undergo breast surgery and adjuvant systemic treatment.
Neoadjuvant endocrine therapy (Arm B)
EXPERIMENTALParticipants in Arm B will receive neoadjuvant endocrine therapy of aromatase inhibitor and OFS for three months, followed by breast surgery.
Interventions
If patients with Oncotype DX RS between 16-25 (for pN0 patients) and 0-25 (for pN1 patients) have an ET response (Ki-67 ≤10%), they are treated with endocrine therapy plus OFS without chemotherapy. Patients without an ET response or with high risk (RS ≧26) receive chemotherapy and endocrine therapy with OFS. Patients with RS ≤ 15 (pN0) are treated with tamoxifen. Adjuvant chemotherapy for pN0 and pN1 is TC and anthracycline-taxane, respectively. Aromatase inhibitor or tamoxifen is co-administered with a LHRH agonist for 5 years. The choice of AI is per investigator discretion. The choice of LHRH agonist and dosing schedule is per investigator's discretion. Endocrine treatment beyond 5 years is at the investigator's discretion.
Patients with Oncotype DX recurrence score (RS) ≧16 (pN0) or pN1 are treated with chemotherapy and endocrine therapy with ovarian function suppression (OFS). Adjuvant chemotherapy for pN0 and pN1 is TC and anthracycline-taxane, respectively. Aromatase inhibitor or tamoxifen co-administered with a LHRH agonist for 5 years. The choice of AI is per investigator discretion. The choice of LHRH agonist and dosing schedule is per investigator's discretion. Endocrine treatment beyond 5 years is at the investigator's discretion. Patients with RS ≤ 15 are treated with tamoxifen.
Eligibility Criteria
You may qualify if:
- Women aged 18 years or older
- ECOG PS 0-1
- HR-positive/HER2-negative breast cancer
- ER expression ≥ 10%
- cN0; HG 1: 3 cm\<T≤5 cm, HG 2: 2 cm\<T≤5 cm or HG3: 1 cm\<T≤5 cm cN1; cT\<5 cm and HG 1/HG 2
- Premenopausal women with spontaneous menses within 12 months
- No distant metastasis of breast cancer
- No prior diagnosis of breast cancer.
- No multiple regions of breast cancer
- No contralateral breat cancer
- Adequate organ function
You may not qualify if:
- Presence of active double cancer (synchronous malignancy requiring treatment).
- Ongoing infectious disease requiring systemic therapy. Fever ≥38.0°C at the time of registration.
- Women who are pregnant, possibly pregnant, within 28 days postpartum, or breastfeeding; men whose partners intend to become pregnant.
- Psychiatric illness or symptoms that interfere with daily living and may compromise trial participation.
- Ongoing systemic administration (oral or IV) of steroids equivalent to ≥10 mg/day of prednisolone or other immunosuppressive agents.
- Unstable angina (developed or worsened within the past 3 weeks) or myocardial infarction within the past 6 months.
- Uncontrolled hypertension.
- Uncontrolled diabetes mellitus despite continuous insulin or oral antidiabetic therapy.
- Positive for HBs antigen or HCV antibodies (Patients positive for HCV antibodies are not excluded if HCV-RNA is undetectable.)
- Positive for HIV antibodies (HIV testing is not mandatory.)
- Presence of interstitial pneumonia, pulmonary fibrosis, or severe emphysema as diagnosed by chest CT.
Contact the study team to confirm eligibility.
Sponsors & Collaborators
- Tokyo Women's Medical Universitylead
- Japan Clinical Oncology Groupcollaborator
Study Sites (49)
Akita University Hospita
Akita, Japan
Chiba Cancer Center
Chiba, Japan
National Hospital Organization Kyushu Cancer Center
Fukuoka, Japan
Fukushima Medical University Hospital
Fukushima, Japan
National Hospital Organization Fukuyama Medical Center
Fukuyama, Japan
Hamamatsu University School of Medicine
Hamamatsu, Japan
Kansai Medical University Hospital
Hirakata, Japan
Hiroshima City North Medical Center Asa Citizens Hospital
Hiroshima, Japan
Hiroshima University Hospital
Hiroshima, Japan
Ibaraki Prefectural Central Hospital
Ibaraki, Japan
Tokai University Hospital
Isehara, Japan
Social medical corporation Hakuaikai Sagara Hospital
Kagoshima, Japan
National Cancer Center Hospital East
Kashiwa, Japan
Saitama Medical Center
Kawagoe, Japan
Kitakyushu Municipal Medical Center
Kitakyushu, Japan
National Hospital Organization Kure Medical Center
Kure, Japan
Gunma University Hospital
Maebashi, Japan
National Hospital Organization Shikoku Cancer Center
Matsuyama, Japan
Aichi Cancer Center
Nagoya, Japan
Nagoya City University
Nagoya, Japan
Nagoya University Hospital
Nagoya, Japan
NHO Nagoya Medical Center
Nagoya, Japan
Niigata Cancer Center Hospital
Niigata, Japan
National Hospital Organization Osaka National Hospital
Osaka, Japan
Osaka International Cancer Institute
Osaka, Japan
National Hospital Organization Nagasaki Medical Center
Ōmura, Japan
Gunma Prefectural Cancer Center
Ōta-ku, Japan
Kitasato University Hospital
Sagamihara, Japan
Saitama Cancer Center
Saitama, Japan
Kindai University Hospital
Sakai, Japan
Hokkaido Cancer Center
Sapporo, Japan
Tohoku University Hospital
Sendai, Japan
Shizuoka Cancer Center
Shizuoka, Japan
Shizuoka General Hospital
Shizuoka, Japan
Institute of Science Tokyo Hospital
Tokyo, Japan
National Cancer Center Hospital
Tokyo, Japan
National Center for Global Health and Medicine
Tokyo, Japan
National Hospital Organization Tokyo Medical Center
Tokyo, Japan
Showa Medical University Hospital
Tokyo, Japan
St.Luke's International Hospital
Tokyo, Japan
The Cancer Institute Hospital of Japanese Foundation for Cancer Research
Tokyo, Japan
Tokyo Metropolitan Cancer and Infectious Diseases Center Komagome Hospital
Tokyo, Japan
Tokyo Women's Medical University Hospital
Tokyo, Japan
Toranomon Hospital
Tokyo, Japan
Mie University Hospital
Tsu, Japan
Tsukuba University Hospital
Tsukuba, Japan
Yamaguchi University Hospital
Ube, Japan
Yao Municipal Hospital
Yao, Japan
Kanagawa Cancer Center
Yokohama, Japan
MeSH Terms
Conditions
Condition Hierarchy (Ancestors)
Central Study Contacts
Study Design
- Study Type
- interventional
- Phase
- phase 3
- Allocation
- RANDOMIZED
- Masking
- NONE
- Purpose
- TREATMENT
- Intervention Model
- PARALLEL
- Sponsor Type
- OTHER
- Responsible Party
- PRINCIPAL INVESTIGATOR
- PI Title
- Associate Professor
Study Record Dates
First Submitted
June 22, 2026
First Posted
June 26, 2026
Study Start
January 28, 2026
Primary Completion (Estimated)
January 27, 2038
Study Completion (Estimated)
January 27, 2039
Last Updated
July 8, 2026
Record last verified: 2026-06