Testing Low Dose Tamoxifen for Invasive Breast Cancer, the (LoTam) Trial

Summary

This phase III trial compares the effect of low dose tamoxifen to usual hormonal therapy, including aromatase inhibitors, in treating post-menopausal women with hormone positive, HER2 negative early stage breast cancer. Tamoxifen is in a class of medications known as antiestrogens. It blocks the activity of estrogen (a female hormone) in the breast. This may stop the growth of some breast tumors that need estrogen to grow. Aromatase inhibitors, such as anastrozole, letrozole, and exemestane, prevent the formation of estradiol, a female hormone, by interfering with an aromatase enzyme. Aromatase inhibitors are used as a type of hormone therapy to treat postmenopausal women with hormone-dependent breast cancer. Giving low dose tamoxifen may be more effective compared to usual hormone therapy in treating post-menopausal women with hormone-positive, HER2 negative early stage breast cancer.

Conditions

• Anatomic Stage 0 Breast Cancer AJCC v8
• Anatomic Stage 1 Breast Cancer AJCC v8
• Anatomic Stage IIA Breast Cancer AJCC v8
• Estrogen Receptor-Positive Breast Carcinoma
• HER2-Negative Breast Carcinoma

Interventions

DRUG

Anastrozole

Given PO

DRUG

Letrozole

Given PO

DRUG

Exemestane

Given PO

DRUG

Tamoxifen

Given PO

PROCEDURE

Mammogram

Undergo mammogram

PROCEDURE

Magnetic Resonance Imaging

Undergo MRI

BIOLOGICAL

Dual X-ray Absorptiometry

Undergo DEXA

PROCEDURE

Biospecimen Collection

Undergo blood sample collection

OTHER

Questionnaire Administration

Ancillary studies

Sponsors & Collaborators

• National Cancer Institute (NCI)

  collaborator NIH

• Alliance for Clinical Trials in Oncology

  lead OTHER

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

NONE

Model

PARALLEL

Eligibility

Min Age

18 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2025-02-19

Primary Completion

2030-11-30

Completion

2031-11-30

Countries

• United States
• Puerto Rico

Study Locations