Background: The efficacy and side-effect profile of ulipristal acetate as compared with those of leuprolide acetate for the treatment of symptomatic uterine fibroids before surgery are unclear.
Methods: In this double-blind noninferiority trial, we randomly assigned 307 patients with symptomatic fibroids and excessive uterine bleeding to receive 3 months of daily therapy with oral ulipristal acetate (at a dose of either 5 mg or 10 mg) or once-monthly intramuscular injections of leuprolide acetate (at a dose of 3.75 mg). The primary outcome was the proportion of patients with controlled bleeding at week 13, with a prespecified noninferiority margin of -20%.
Results: Uterine bleeding was controlled in 90% of patients receiving 5 mg of ulipristal acetate, in 98% of those receiving 10 mg of ulipristal acetate, and in 89% of those receiving leuprolide acetate, for differences (as compared with leuprolide acetate) of 1.2 percentage points (95% confidence interval [CI], -9.3 to 11.8) for 5 mg of ulipristal acetate and 8.8 percentage points (95% CI, 0.4 to 18.3) for 10 mg of ulipristal acetate. Median times to amenorrhea were 7 days for patients receiving 5 mg of ulipristal acetate, 5 days for those receiving 10 mg of ulipristal acetate, and 21 days for those receiving leuprolide acetate. Moderate-to-severe hot flashes were reported for 11% of patients receiving 5 mg of ulipristal acetate, for 10% of those receiving 10 mg of ulipristal acetate, and for 40% of those receiving leuprolide acetate (P<0.001 for each dose of ulipristal acetate vs. leuprolide acetate).
Conclusions: Both the 5-mg and 10-mg daily doses of ulipristal acetate were noninferior to once-monthly leuprolide acetate in controlling uterine bleeding and were significantly less likely to cause hot flashes. (Funded by PregLem; ClinicalTrials.gov number, NCT00740831.).