A randomized study on pharmacodynamic effects of vaginal rings delivering the progesterone receptor modulator ulipristal acetate: research for a novel estrogen-free, method of contraception

作者：Huang YongMei; Jensen Jeffrey T; Brache Vivian; Cochon Leila; Williams Alistair; Miranda Maria Jose; Croxatto Horacio; Kumar Narender; Sussman Heather; Hoskin Elena; Plagianos Marlena; Roberts Kevin; Merkatz Ruth; Blithe Diana; Sitruk Ware Regine^*

来源：Contraception, 2014, 90(6): 565-574.

DOI：10.1016/j.contraception.2014.08.006

• Ulipristal acetate
• Contraception
• Pharmacodynamics
• Endometrium
• Vaginal ring

Objective: To determine whether a 3-month contraceptive vaginal ring (CVR) delivering ulipristal acetate (UPA) can inhibit ovulation in 90% of cycles. %26lt;br%26gt;Study Design: This was a randomized dose-finding parallel group clinical trial. Fifty-five healthy women with normal ovulation at baseline were randomized to receive a low-dose (1500 mu g/day) or a high-dose (2500 mu g/day) UPA-CVR for two consecutive 12-week treatment periods, followed by a recovery cycle. A subgroup of women received levonorgestrel (LNG) 1.5 mg orally twice (at the end of both 12-week ring periods) or once (at the end of the 24-week treatment). The primary outcome was ovulation suppression assessed by transvaginal ultrasound and hormone levels. Secondary outcomes included endometrial safety and bleeding patterns. %26lt;br%26gt;Results: All subjects showed normal ovulation at baseline and recovery. Ovulation suppression was seen in 81.8% (95% CI: 73.3%, 88.5%) and 86.1% (95% CI: 78.1%, 92%) of treatment cycles with low and high-dose, respectively. Benign progesterone receptor modulator associated endometrial changes (PAEC) were seen during treatment; 78.8% at week 24, but resolved at recovery cycle. A few cases of heavy bleeding occurred near the end of the 24-week treatment, but a single dose of LNG every 12 weeks reduced the increase in endometrial thickness during the second treatment period and prevented excessive bleeding. %26lt;br%26gt;Conclusion: The 3-month UPA-CVR may become an effective long-acting, user-controlled estrogen-free contraceptive. The greatest suppression of ovulation was seen with the 2500-mu g/day ring. %26lt;br%26gt;Implications: The 3-month CVR delivering UPA 2500 mu g/day can become an effective user-controlled estrogen-free contraceptive method. Benign PAEC during treatment returns to normal after discontinuation. The prevention of occasional excessive withdrawal bleeding, either by a progestin or by using higher UPA levels to increase follicle suppression may permit prolonged treatment.

• 出版日期2014-12