Effect of Metformin on Endometrial Thickness in Postmenopausal Breast Cancer Patients Receiving Tamoxifen

Uruk University

Status: Completed

Conditions: Breast Cancer; Endometrial Hyperplasia and Endometrial Cancers

Treatments: Drug: tamoxifen; Drug: Metfomin; Drug: Placebo matching Metformin

Study type: Interventional

Funder types: Other

Identifiers

NCT07145827

UU-TAM-MET-2024-01

Details and patient eligibility

About

The goal of this clinical trial is to learn if metformin can reduce the increase in endometrial thickness caused by tamoxifen in women with estrogen-positive breast cancer taking tamoxifen for more than 1 year. It will also learn about the safety of taking metformin with tamoxifen. The main questions it aims to answer are:

1. Does metformin decrease endometrial thickness in women receiving tamoxifen?
2. What medical problems do participants have when taking metformin with tamoxifen?

Researchers will compare tamoxifen plus metformin to tamoxifen plus placebo to see if metformin works to reduce endometrial thickness compared to placebo patients.

Participants will:

1. Take metformin daily along with tamoxifen, or take tamoxifen with placebo.
2. Acquire baseline assessment and then visit the clinic at 3 months, 6 months, 9 months and 12 months for checkups and trans abdominal ultrasound test for endometrial thickness, and to be monitored for any side effects or complications.

Enrollment: 60 patients

Sex: Female

Volunteers: No Healthy Volunteers

Inclusion criteria

• Postmenopausal Female patients (amenorrhea ≥ 12 months).
• Histologically proven (Estrogen-positive) breast cancer.
• Completed all required surgery and/or chemotherapy (if indicated)
• On adjuvant tamoxifen for at least 1 year.
• Accepts to enroll in the study

Exclusion criteria

• Refusing to enroll in the study
• Ongoing or History of: endometrial or ovarian malignancy
• Concurrent hormonal therapy that might affect endometrial thickness
• Concurrent Diabetes mellitus in which metformin is prescribed.
• Known hypersensitivity or severe intolerance to metformin

Trial design

Primary purpose: Prevention

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Double Blind

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60 participants in 2 patient groups, including a placebo group

Tamoxifen + Metformin

Experimental group

Description:

Participants in this arm (n=30) will continue taking the standard oncological tamoxifen dose as prescribed and receive an addition of metformin 500mg twice daily, titrated to tolerance, during the 12-month study period.

Treatment:

Drug: Metfomin

Drug: tamoxifen

Tamoxifen + Placebo

Placebo Comparator group

Description:

Participants in this arm (n=30) will continue to receive the standard oncological dose of tamoxifen as prescribed, in addition to a placebo tablet matching the shape size and color of metformin tablet twice daily during the 12 months study period; they will act as the control group.

Treatment:

Drug: Placebo matching Metformin

Drug: tamoxifen