Combination of Letrozole, Everolimus and TRC105 in Postmenopausal Women With Hormone-Receptor Positive and Her2 Negative Breast Cancer

February 5, 2026 updated by: Christos Vaklavas, MD, University of Alabama at Birmingham

A Phase I/II Study of Preoperative (Neoadjuvant) Combination of Letrozole (Femara), Everolimus (Afinitor), and TRC105 in Postmenopausal Women With Newly Diagnosed Local or Locally Advanced Potentially Resectable Hormone-Receptor Positive and Her2 Negative Breast Cancer

This study will test how well a new combination of three drugs (Letrozole, Everolimus, and TRC105) is tolerated and how well it works in Stage 2 and 3 breast cancer when given prior to definitive surgery. Letrozole blocks the estrogen receptor expressed by many breast cancers while everolimus blocks signals that drive cancer cells to grow. TRC105 is an investigational drug that blocks the formation and growth of blood vessels that feed the cancer and promote its growth. The goal of this study is to investigate the safety and efficacy of this multitargeted approach in breast cancer.

Study Overview

Status

Completed

Conditions

Detailed Description

In postmenopausal women with hormone receptor-positive and Her2 negative non-metastatic breast cancer, downstaging or the achievement of a complete pathologic remission before definitive surgery has been associated with the lowest risk of recurrence of breast cancer. In order to achieve a better response in these patients in the preoperative setting, this study combines 3 potentially synergistic agents. Letrozole blocks the synthesis of estrogens and, in doing so, deprives the tumor from hormones which drive its growth. Everolimus is a drug that blocks growth factor signaling which is essential for tumor cells to maintain their growth and proliferation. Everolimus has already been shown to work very well in this subtype of breast cancer in the recurrent and metastatic setting. TRC105 is an investigational agent that prevents the formation and growth of new blood vessels that support tumors by providing oxygen and nutrients.

The study has 2 components. First the investigators will determine the ideal in terms of tolerance combination of doses of the 3 agents. Once the ideal regimen is determined, more patients will be treated with the investigational combination. During this second stage, the investigators will get a preliminary idea of how effective the investigational therapy is. Further studies will need to be done to confirm the efficacy of the investigational combination.

Study Type

Interventional

Enrollment (Actual)

15

Phase

  • Phase 2
  • Phase 1

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

    • Alabama
      • Birmingham, Alabama, United States, 35294
        • University of Alabama at Birmingham

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

19 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Recent diagnosis of hormone receptor positive and HER2 negative breast cancer.
  • Stage 2 and 3 hormone receptor positive and HER2 negative breast cancer (stage T2-4 but not inflammatory, N0-2, M0).
  • Histological grade I, II or III according to the modified Bloom Richardson scale.
  • No prior treatment specific for breast cancer.
  • Postmenopausal status as defined by the National Comprehensive Cancer Network.
  • ECOG performance status < 2 (Karnofsky > 60%).
  • Must have signed study-specific informed consent.
  • Liver Function Tests < 2.5 times the upper normal limit (UNL).
  • ANC ≥ 1,500/mm3, platelets ≥ 100,000/mm3, Hemoglobin ≥ 10g%.
  • Renal function: serum creatinine < 1.5 institutional UNL or creatinine clearance > 40 cc/min.

Exclusion Criteria:

  • Inflammatory breast cancer.
  • Pre- and peri-menopausal state.
  • Pregnancy.
  • Metastatic disease.
  • HER2 positive breast cancer by immunohistochemistry or FISH.
  • Triple negative breast cancer (hormone receptor and Her2 negative).
  • Disease that cannot be followed by imaging studies.

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: Phase I Cohort 1
Letrozole 2.5 mg PO daily until surgery, everolimus 5 mg PO daily for 24 weeks, and TRC105 15 mg/kg IV q 2 weeks for 24 weeks
A dose of 2.5 mg of letrozole will be given orally once each day until one day before surgery. This drug is commercially available and is not provided by the study.
Other Names:
  • Femara
The dose of everolimus will be escalated from 5 mg to 10 mg daily depending upon the cohort in Phase I. It is administered as an oral pill to be taken once daily up until four weeks prior to surgery.
Other Names:
  • Afinitor
The dose for TRC105 is either 15 or 10 mg/kg to be given intravenously every two weeks and continued until four weeks prior to surgery.
Experimental: Phase I Cohort 2
Letrozole 2.5 mg PO daily until surgery, everolimus 10 mg PO daily for 24 weeks, and TRC105 15 mg/kg IV q 2 weeks for 24 weeks
A dose of 2.5 mg of letrozole will be given orally once each day until one day before surgery. This drug is commercially available and is not provided by the study.
Other Names:
  • Femara
The dose of everolimus will be escalated from 5 mg to 10 mg daily depending upon the cohort in Phase I. It is administered as an oral pill to be taken once daily up until four weeks prior to surgery.
Other Names:
  • Afinitor
The dose for TRC105 is either 15 or 10 mg/kg to be given intravenously every two weeks and continued until four weeks prior to surgery.
Experimental: Phase I Cohort -1
Letrozole 2.5 mg PO daily until surgery, everolimus 5 mg PO daily for 24 weeks, and TRC105 10 mg/kg IV q 2 weeks for 24 weeks
A dose of 2.5 mg of letrozole will be given orally once each day until one day before surgery. This drug is commercially available and is not provided by the study.
Other Names:
  • Femara
The dose of everolimus will be escalated from 5 mg to 10 mg daily depending upon the cohort in Phase I. It is administered as an oral pill to be taken once daily up until four weeks prior to surgery.
Other Names:
  • Afinitor
The dose for TRC105 is either 15 or 10 mg/kg to be given intravenously every two weeks and continued until four weeks prior to surgery.
Experimental: Phase II
Letrozole 2.5 mg PO daily until surgery, everolimus 5 or 10 mg PO daily for 24 weeks, and TRC105 15 or 10 mg/kg IV q 2 weeks for 24 weeks. Dose and regimen to be determined based on data from the phase I component.
A dose of 2.5 mg of letrozole will be given orally once each day until one day before surgery. This drug is commercially available and is not provided by the study.
Other Names:
  • Femara
The dose of everolimus will be escalated from 5 mg to 10 mg daily depending upon the cohort in Phase I. It is administered as an oral pill to be taken once daily up until four weeks prior to surgery.
Other Names:
  • Afinitor
The dose for TRC105 is either 15 or 10 mg/kg to be given intravenously every two weeks and continued until four weeks prior to surgery.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Number of Participants Who Experienced Dose-limiting Toxicities
Time Frame: 4 weeks

This outcome will report the number of patients who experienced a dose-limiting Toxicity (DLT) in Phase I Cohort 1, Phase I Cohort 2, and Phase I Cohort -1. A DLT was defined as:

  1. A grade 3 or 4 non-hematologic toxicity except anorexia, alopecia, nausea (which is not refractory to antiemetics), fatigue, and fever without neutropenia;
  2. Failure to recover to baseline (except alopecia) after delaying the next dose by more than 14 days;
  3. Grade 3 or 4 neutropenia complicated by fever >38.5°C or infection, or grade 4 neutropenia of ≥7 days duration; or
  4. Grade 4 thrombocytopenia, or grade 3 thrombocytopenia complicated by hemorrhage.

The maximum tolerated dose (MTD) is defined as the highest dose at which 0 out of the first 3 or 1 out of a total of 6 patients experience DLT during the first cycle of therapy; this dose level will be the recommended phase 2 dose (RP2D) in the Phase II Group.

4 weeks

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Rates of Pathologic Complete Remission (pCR)
Time Frame: 24 weeks up to time of surgery

The 2-dimensional size of the surgically excised residual tumor was measured and compared to the radiographic size of the tumor at baseline.

Per Response Evaluation Criteria In Solid Tumors Criteria (RECIST v1.1) for target lesions and assessed by MRI:

Complete Response (CR), Disappearance of all target lesions and reduction in short axis of any pathological lymph nodes to <10 mm; Partial Response (PR), >=30% decrease in the sum of the longest diameter of target lesions; Overall Response (OR) = CR + PR.

24 weeks up to time of surgery
C Max - Letrozole
Time Frame: Day 1 and Day 29
Maximum serum concentration of Letrozole.
Day 1 and Day 29
Tumor Proliferation Changes
Time Frame: 24 weeks (pretreatment to time of definitive surgery)
This outcome will report the change in tumor cell proliferation. This was measured by the change in the percentage of Ki67 positive cells from pretreatment to surgery (up to 24 weeks): (%Ki67(+) cells pretreatment - %Ki67(+) cells posttreatment)/(%Ki67(+) cells pretreatment) * 100 Ki67 is a protein found in cells that are dividing. The Ki-67 assessment was performed by the clinical histology laboratory using a validated assay. The results were evaluated by a board-certified pathologist, who estimated the proportion of cancer cells stained for Ki-67. The individual tissue sections were analyzed blindly and at the completion of the assay, results were correlated per case as to changes in Ki-67 with the investigational therapy.
24 weeks (pretreatment to time of definitive surgery)
T Max - Letrozole
Time Frame: Day 1
T Max is the time to the maximum serum concentration of a drug in the blood. This outcome will report the T Max of Letrozole at Day 1 in Phase 1 Cohort 1, Phase 1 Cohort 2, and Phase 2. All patients in the trial received the same dose of letrozole.
Day 1
AUC - Letrozole
Time Frame: Day 1 and Day 29

This outcome will report the area under the serum concentration of letrozole versus time curve (AUC-L).

AUC-L is the integral of the concentration of letrozole in the blood as a function of time. AUC-L measures how much letrozole reaches the bloodstream in a period of time after a dose is given. This is useful in dose determination and assessing drug interactions.

This outcome was assessed on Day 1 and on Day 29 for Phase I Cohort I, Phase I Cohort 2, and Phase 2.

Day 1 and Day 29
T 1/2 - Letrozole
Time Frame: Day 1
T ½ is the half-life of a drug in the blood. This is the time it takes for the concentration of the drug in the blood to be reduced by half. This outcome will report the T 1/2 of Letrozole.
Day 1
C Max - Everolimus
Time Frame: Day 1 and Day 29
Cmax is the maximum serum concentration of a drug in the blood. This outcome will report the Cmax of Everolimus in Phase 1 Cohort 1 and Phase 1 Cohort 2 combined with Phase 2 (since the dose of everolimus was the same in these cohorts) at Day 1 and Day 29.
Day 1 and Day 29
T Max Everolimus
Time Frame: Day 1
T Max is the time to the maximum serum concentration of a drug in the blood. This outcome will report the T Max of Everolimus in Phase 1 Cohort 1, and combined Phase 1 Cohort 2 and Phase 2 (since patients received the same dose of everolimus) at Day 1.
Day 1
AUC - Everolimus
Time Frame: Day 1 and Day 29

This outcome will report the area under the serum concentration everolimus of versus the time curve (AUC-E).

AUC-E is the integral of the concentration of everolimus in the blood as a function of time. AUC-E measures how much everolimus reaches the bloodstream in a period of time after a dose is given. This is useful in dose determination and assessing drug interactions.

This outcome was assessed on Day 1 and on Day 29 for Phase I Cohort I, and combined Phase I Cohort 2 and Phase 2 (since patients in Phase I cohort 2 and Phase 2 received the same dose of everolimus).

Day 1 and Day 29
T 1/2 - Everolimus
Time Frame: day 1
T ½ is the half-life of a drug in the blood. This is the time it takes for the concentration of the drug in the blood to be reduced by half. This outcome will report the T 1/2 of Everolimus in Phase 1 Cohort 1 and combined Phase 1 Cohort 2 and Phase 2 at Day 1 (since patients in Phase 1 Cohort 2 and Phase 2 at Day 1 received the same dose of everolimus).
day 1

Collaborators and Investigators

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

Investigators

  • Principal Investigator: Erica Stringer-Reasor, M.D., University of Alabama at Birmingham
  • Principal Investigator: Erica Stringer-Reasor, MD, University of Alabama at Birmingham

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the 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)

February 1, 2015

Primary Completion (Actual)

December 1, 2022

Study Completion (Actual)

December 1, 2022

Study Registration Dates

First Submitted

July 30, 2015

First Submitted That Met QC Criteria

August 6, 2015

First Posted (Estimated)

August 11, 2015

Study Record Updates

Last Update Posted (Actual)

February 6, 2026

Last Update Submitted That Met QC Criteria

February 5, 2026

Last Verified

February 1, 2026

More Information

Terms related to this study

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

UNDECIDED

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

Yes

Studies a U.S. FDA-regulated device product

No

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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