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OncoMatch/Clinical Trials/NCT04614194

Single Cell Immune and Non-immune Correlates of Response to Neoadjuvant Abemaciclib

Is NCT04614194 recruiting? Yes, currently enrolling (Jun 2026). This Phase 2 trial studies multiple treatments including Letrozole and Abemaciclib for breast cancer.

Phase 2RecruitingUniversity of Texas Southwestern Medical CenterNCT04614194Data as of Jun 2026

Treatment: Letrozole · AbemaciclibThe purpose of this study is to better understand how the immune system plays a role in fighting breast cancer and specifically research if the immune system response against breast cancer can be improved with endocrine therapy and cyclin dependent kinase inhibitor therapy in patients with hormone receptor positive breast cancer. This will be studied by collecting tumor tissue and blood samples before and after 2 weeks of study treatment with commonly used endocrine therapy and cyclin dependent kinase inhibitor therapy.

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Extracted eligibility criteria

Treatments studied

Targeted therapy

Abemaciclib

Endocrine / hormonal

Letrozole

Cancer type

Breast Carcinoma

Biomarker criteria

Required: ESR1 positive

estrogen receptor or progesterone receptor positive by immunohistochemistry

Required: PR (PGR) positive

estrogen receptor or progesterone receptor positive by immunohistochemistry

Required: HER2 (ERBB2) wild-type (Herceptest (0 or 1+) or not amplified by in situ hybridization)

HER2 negative by Herceptest (0 or 1+) or not amplified by in situ hybridization

Disease stage

Required: Stage I, II, III

Clinical stage operable stage I, II, or III

Performance status

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

Demographics

Female only

Prior therapy

No prior treatment (treatment-naive required)

Cannot have received: chemotherapy

Chemotherapy ... for current diagnosis of breast cancer

Cannot have received: radiotherapy

Radiotherapy ... for current diagnosis of breast cancer

Cannot have received: any other cancer therapy

any other cancer therapy for current diagnosis of breast cancer

Cannot have received: investigational agents

Subjects may not have received or be receiving any other investigational agents for the treatment of the cancer under study

Lab requirements

Blood counts

anc ≥1,500/mcl, platelets ≥100,000/mcl, hemoglobin ≥8 g/dl

Kidney function

creatinine clearance >30 ml/minute

Liver function

total bilirubin ≤1.5 × upper limit of normal, alt and ast ≤3 × upper limit of normal

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

US trial sites

  • Parkland Hospital · Dallas, Texas
  • University of Texas Southwestern Medical Center · Dallas, Texas

Showing up to 5 US sites.

See all sites on ClinicalTrials.gov →

Frequently asked questions

Is NCT04614194 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 positive is a required biomarker for enrollment.

Does this trial require PGR?

Yes, PGR positive 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 or III 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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