Letrozole treatment for uterine fibroids

Letrozole for Treatment of Uterine Fibroids: A Randomized, Placebo-Controlled Trial

This study tests if letrozole, a drug usually used for breast cancer, can help women with uterine fibroids feel better and improve their quality of life.

Quick facts

• Phase: Phase 4
• Study type: Interventional
• Enrollment: 140 (estimated)
• Ages: 21 Years to 53 Years
• Sex: Female
• Sponsor: University of California, San Francisco (Academic / other)
• Drugs / interventions: denosumab
• Locations: 5 sites (Los Angeles, California and 4 other locations)
• Trial ID: NCT06143631 on ClinicalTrials.gov

What this trial studies

This clinical trial evaluates the effectiveness of letrozole, a medication typically used for breast cancer, in treating symptoms associated with uterine leiomyomas (fibroids). It is a randomized, double-blinded, placebo-controlled study that compares the effects of letrozole against a placebo on symptom relief and quality of life for women suffering from these conditions. Participants will be monitored for changes in leiomyoma size and associated symptoms over the course of the trial.

Who should consider this trial

Good fit: Ideal candidates are premenopausal women aged 21 to 54 with diagnosed uterine leiomyomas and moderate to severe symptoms.

Not a fit: Patients who do not have uterine leiomyomas or those with mild symptoms may not benefit from this study.

Why it matters

Potential benefit: If successful, this treatment could significantly alleviate symptoms and improve the quality of life for women suffering from uterine fibroids.

How similar studies have performed: Previous studies have shown promise in using hormonal treatments for fibroids, but this specific approach with letrozole is relatively novel.

Eligibility criteria

Inclusion Criteria:

* At least 21 and less than 54 years of age (to focus on an adult, premenopausal population)
* Female sex, based on sex identified on their birth certificate (no other gender requirements)
* Have uterine leiomyomata that have been visualized on pelvic imaging (i.e., ultrasound or MRI) in the last 24 months
* Report symptoms associated with leiomyomata such as heavy uterine bleeding, pelvic pressure or discomfort, urinary or bowel abnormalities, or dyspareunia for the past 3 months
* Have at least moderate leiomyomata symptom burden, with UFS-QOL SSS score of 30 or higher at baseline
* Has regularly occurring menstrual periods of ≤ 14 days duration with a cycle of 21 to 38 days from the start of one menstrual period until the start of the next, by patient history for at least 3 months prior to screening
* Agree to use a non-hormonal or barrier method of contraception with any sexual activity with a non-sterile male partner during the study period (i.e., use of copper IUD is consistent with eligibility)

Exclusion Criteria:

* Screening pelvic imaging indicating any leiomyomata ≥10 cm in maximum diameter, or uterine size ≥16 cm in length (equivalent to 16 weeks gestation)-note that candidates who exclusively have prior clinical pelvic imaging 12-24 months ago will be excluded if imaging includes leiomyomata ≥9 cm in maximum diameter, or uterine size ≥15 cm in length, presuming leiomyoma growth of ≥1 cm per year
* Screening pelvic imaging indicating only one, sole leiomyoma \<2 cm in maximum diameter
* Any submucosal leiomyoma that is \>50% within uterine cavity (FIGO Type 0 or Type 1 leiomyomata)
* Visit to the emergency room or hospitalization for leiomyoma symptoms in the last 12 weeks
* Leiomyomata treated by surgery, radiologic procedure in the last 12 weeks; or plans to undergo any of the above in the next 24 weeks
* Leiomyomata treated by GRNH agonist or antagonist in the last 12 weeks; or plans to use the above in the next 24 weeks
* Currently pregnant or lactating, pregnant or lactating in the past 12 weeks, or planning to become pregnant in the next 24 weeks
* Screening serum hemoglobin \<8 g/dL, or history of blood transfusion in the last 12 weeks (indicating severe anemia)
* Screening cholesterol lipid panel testing showing LDL cholesterol level ≥ 190 mg/dL (due to rare side effects over long-term use of aromatase inhibitors in postmenopausal women)
* Screening serum estradiol level \<30 pg/mL (consistent with postmenopausal status)
* Irregularly timed bleeding, including bleeding or spotting in between periods, in the past 3 months.
* History of osteoporosis (based on self-reported DEXA indicating bone mineral density Z-score \< -2.0 at spine, total hip, or femoral neck; a prior fracture judged to be a fragility fracture; or self-reported use of bisphosphonates, calcitonin, calcitriol, ipriflavone, teriparatide, or denosumab for bone density loss)
* History of severe liver disease (Child Pugh Class C cirrhosis), posing safety risks for use of letrozole
* Current or prior history of breast cancer (given potential need to take letrozole for breast cancer treatment or secondary prevention)
* Screening pelvic imaging indicating an Ovarian-Adnexal Reporting and Data System (O-RADS) category 3, 4, or 5 ovarian or adnexal lesion
* Screening pelvic imaging concerning for other current cancer of the gynecologic, genitourinary or gastrointestinal system
* Prior hypersensitivity or significant adverse reaction to letrozole or any aromatase inhibitor, or to an ingredient in the placebo capsule
* Use of letrozole, other aromatase inhibitor, or selective estrogen receptor modulator (SERM) medications in the past 4 weeks, or existing plans to initiate one of these in the next 24 weeks
* Use of oral, vaginal, or topical exogenous estrogen, progestin, or androgen therapy in the past 4 weeks; or injectable forms of the above in the past 12 weeks; or plans to initiate any of the above in the next 24 weeks
* Use of medications with potential unsafe interactions with letrozole in the past 4 weeks (methadone, levomethadone, nintedanib, thalidomide), or plans to initiate these in the next 24 weeks
* Any condition that, in the opinion of the investigators, would interfere with ability to complete study procedures, including acute or uncontrolled mental health condition, substance abuse, or inability to complete procedures in English (or Spanish, for sites that offer study assessments in Spanish)

Where this trial is running

Los Angeles, California and 4 other locations

• University of California, Los Angeles — Los Angeles, California, United States (Recruiting)
• University of California, San Francisco — San Francisco, California, United States (Recruiting)
• Mayo Clinic — Rochester, Minnesota, United States (Recruiting)
• University of Mississippi Medical Center — Jackson, Mississippi, United States (Recruiting)
• Duke University — Durham, North Carolina, United States (Recruiting)

Study contacts

• Principal investigator: Vanessa Jacoby, MD, MAS — University of California, San Francisco
• Study coordinator: Study Coordinator

Conditions Leiomyoma, Uterine; Leiomyoma; Fibroid; Fibroid Uterus