Low-dose mifepristone for uterine leiomyomata.
OBJECTIVE
To compare the effect of 5 and 10 mg of mifepristone on uterine leiomyoma size and symptoms, and to measure side effects.


METHODS
Forty premenopausal women with large, symptomatic leiomyomata were randomized to receive either 5 or 10 mg of mifepristone daily for 6 months in an open-label study. Uterine volume was measured at bimonthly intervals by sonography. Serum concentrations of hemoglobin levels, follicle-stimulating hormone, and liver enzymes were obtained, and endometrial samples, symptoms, and menstrual bleeding were also assessed.


RESULTS
Nineteen of 20 subjects taking 5 mg and all 20 subjects taking 10 mg completed all 6 months of the study. Mean uterine volume shrank by 48% (P <.001) in the 5-mg group and 49% (P <.001) in the 10-mg group, a nonsignificant difference. Leiomyoma-related symptoms were comparably reduced in both groups. Amenorrhea occurred in 60-65% of both groups. Hemoglobin levels increased by 2.5 g/dL in anemic subjects. The incidence of hot flashes increased significantly over baseline in the 10-mg group but not in the 5-mg group. Simple endometrial hyperplasia occurred in 28% of all subjects, with no difference between groups. No atypical hyperplasia was noted.


CONCLUSIONS
Mifepristone in doses of 5 mg or 10 mg results in comparable leiomyoma regression, improvement in symptoms, and few side effects. Further study is needed to assess the long-term safety and efficacy of low-dose mifepristone.
Eisinger
Steven H
SH
Department of Family Medicine, School of Medicine, University of Rochester, Rochester, New York, USA. eisinger@rochester.edu
Meldrum
Sean
S
Fiscella
Kevin
K
le Roux
Heleen D
HD
Guzick
David S
DS
D000328:Adult; D001707:Biopsy, Needle; D001774:Blood Chemical Analysis; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D019160:Endosonography; D005260:Female; D005500:Follow-Up Studies; D006727:Hormone Antagonists / Q000008:administration & dosage*; D006801:Humans; D007150:Immunohistochemistry; D007889:Leiomyoma / Q000175:diagnosis* / Q000188:drug therapy*; D008875:Middle Aged; D015735:Mifepristone / Q000008:administration & dosage*; D015999:Multivariate Analysis; D012016:Reference Values; D018709:Statistics, Nonparametric; D016896:Treatment Outcome; D014594:Uterine Neoplasms / Q000175:diagnosis* / Q000188:drug therapy*
D006727:Hormone Antagonists; D015735:Mifepristone