TRIP

Ulipristal versus Leuprolide for Fibroids

Now@NEJM, 2012

In involving women with symptomatic fibroids who were planning to undergo surgery, treatment with the selective progesterone-receptor modulator ulipristal acetate was effective in controlling excessive bleeding and reducing fibroid size at 13 weeks.
Uterine leiomyomas, or fibroids, are the most common benign uterine tumors in women of reproductive age.
In addition to anemia caused by heavy bleeding, fibroids can cause pelvic pain, pressure, dysmenorrhea, reduced quality of life, and infertility.
Current management strategies consist mainly of surgical or radiologic interventions; options for medical therapy are limited.
The use of oral progestins has not been extensively investigated, but small studies report breakthrough bleeding and possible promotion of myoma growth.
The use of a progestin-releasing intrauterine device controls menorrhagia in some patients, but trials have generally excluded patients with uteri distorted by submucosal myomas.
Gonadotropin-releasing hormone (GnRH) agonists are considered to be the most effective medical therapy.
In a placebo-controlled trial, the GnRH agonist leuprolide acetate (in a 3.75-mg depot formulation) stopped vaginal bleeding in 85% of patients with anemia before myoma surgery.
However, leuprolide acetate suppresses estradiol, and in that trial, 67% of patients reported hot flashes.
Ulipristal acetate is a potent and selective modulator of progesterone-receptor activity (SPRM) in vitro and in vivo.
Studies of cultured leiomyoma cells have shown antiproliferative, antifibrotic, and proapoptotic effects of ulipristal acetate on leiomyoma cells but not on normal myometrial cells.