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for females ages 21 years and up
at San Francisco, California
study started
estimated completion:
Principal Investigator



PLUM evaluates the drug letrozole as a treatment for uterine fibroids. This study is a randomized, blinded, placebo-controlled trial of oral letrozole among premenopausal women with symptomatic uterine fibroids. Participants will be randomly assigned in a 1:1 ratio to either oral letrozole 2.5mg/day for 6 months (Group A) or intermittent dosing with letrozole 2.5mg/day and an identical placebo capsule (Group B).


Leiomyoma Uterine Fibroids Letrozole


You can join if…

Open to females ages 21 years and up

  1. ≥21 years old
  2. Premenopausal (at least one menses in last 3 months)
  3. Symptomatic fibroids (fibroids visualized on ultrasound or MRI and heavy uterine bleeding, pelvic pressure or discomfort, urinary or bowel abnormalities, dyspareunia)
  4. Fibroids that are ≤4 in total number or Fibroids that are ≤7 in total number if all fibroids are less than 4cm (40 mm) each
  5. Fibroids that are ≤7cm in maximum diameter, on screening imaging, if ≤4 fibroids in total number(fibroid is defined as any mass with radiographic characteristics of fibroid>2cm)
  6. Up to date in Pap smear screening and surveillance
  7. Endometrial biopsy (required if age>45 years with irregular bleeding) does not indicate premalignant or malignant cells
  8. Agree to use non-hormonal barrier method of contraception during study period if at risk for pregnancy
  9. Has primary care provider or gynecologist
  10. Agrees not to start new medications/treatments for fibroids during the study
  11. Able to give informed consent

You CAN'T join if...

  1. Fibroids treated by surgery, radiologic procedure, or GnRH agonist or antagonist in the last 3 months
  2. Any submucosal fibroid ≥2cm that is>50% in uterine cavity (FIGO Type 0 or Type 1 fibroids) amenable to hysteroscopic resection
  3. Use of exogenous estrogen and/or progestin in the last month. (for 3 month long-acting depoprovera injection, no use in last 3 months)
  4. Pregnant, lactating, or planning to become pregnant in the next 6 months
  5. Hematocrit <27% or visit to emergency room or hospitalization for fibroid symptoms in the last 3 months (cannot be safely randomized to a placebo)
  6. History of osteopenia or osteoporosis
  7. History of hyperlipidemia
  8. Current liver or kidney disease
  9. Unable or unwilling to attend 4 study visits
  10. Pelvic imaging concerning for gynecologic cancer or cancer of the genitourinary or gastrointestinal system
  11. Does not have primary care provider or gynecologist



in progress, not accepting new patients
Start Date
Completion Date
University of California, San Francisco
Phase 4
Lead Scientist
Vanessa Jacoby
Study Type
Last Updated
January 1, 2017