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OncoMatch/Clinical Trials/NCT06361940

Molecular Analyses to Predict Pathways of Endocrine Resistance Following Short Term Neoadjuvant Endocrine Treatment in Patients With Hormone Receptor-Positive HER2-negative Breast Cancer

Is NCT06361940 recruiting? Yes, currently enrolling (Jun 2026). This Phase 2 trial studies Aromatase inhibitors or tamoxifen for breast cancer.

Phase 2RecruitingMedical College of WisconsinNCT06361940Data as of Jun 2026

Treatment: Aromatase inhibitors or tamoxifenThis is an exploratory phase II interventional study that initiates standard-of-care anti-estrogen treatment preoperatively for 4-12 weeks (+/- 2 weeks).

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Extracted eligibility criteria

Treatments studied

Other

Aromatase inhibitors or tamoxifen

Cancer type

Breast Carcinoma

Biomarker criteria

Required: ESR1 overexpression (≥1% positively staining cells by immunohistochemistry)

Estrogen and/or progesterone receptor positive tumor defined ≥1% positively staining cells by immunohistochemistry

Required: PR (PGR) overexpression (≥1% positively staining cells by immunohistochemistry)

Estrogen and/or progesterone receptor positive tumor defined ≥1% positively staining cells by immunohistochemistry

Required: HER2 (ERBB2) wild-type (negative by immunohistochemistry (IHC) or fluorescence in situ hybridization (FISH))

HER2 /neu must be negative by immunohistochemistry (IHC) or fluorescence in situ hybridization (FISH)

Disease stage

Required: Stage I, II (AJCC)

clinical stage I or II; AJCC clinical T4, N1-3 or M1, breast cancer [excluded]

Performance status

ECOG 0–2(Ambulatory, capable of self-care)

Demographics

Female only

Prior therapy

No prior treatment (treatment-naive required)

Cannot have received: any treatment for this breast cancer or for any malignancy diagnosed or treated within the past two years

Exception: non-melanomatous skin cancer, carcinoma in situ of the cervix

Patients must not have had a prior treatment for this breast cancer or for any malignancy diagnosed or treated within the past two years, with the exception of non-melanomatous skin cancer, carcinoma in situ of the cervix.

Structured fields extracted by AI. May contain errors — verify against the official protocol.

US trial sites

  • Froedtert Hospital and the Medical College of Wisconsin · Milwaukee, Wisconsin

Showing up to 5 US sites.

See all sites on ClinicalTrials.gov →

Frequently asked questions

Is NCT06361940 currently recruiting?

Yes, this trial is currently recruiting patients.

Can patients have received prior systemic therapy?

No. This trial requires treatment-naive patients — prior systemic therapy is an exclusion criterion.

Does this trial require ESR1?

Yes, ESR1 overexpression is a required biomarker for enrollment.

Does this trial require PGR?

Yes, PGR overexpression is a required biomarker for enrollment.

Does this trial require ERBB2?

Yes, ERBB2 wild-type is a required biomarker for enrollment.

What disease stage is eligible?

Stage I or II is required.

Is this trial open to male patients?

No. This trial enrolls female patients only.

Could you qualify for this trial?

Enter your biomarker results to see how this trial's eligibility criteria match your specific cancer profile.

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