SAN FRANCISCO — A new drospirenone-based OC awaiting approval by the Food and Drug Administration is effective in relieving premenstrual symptoms because it is given in a low dose and for an extended regimen, according to new research.
Drospirenone is a progestin derived from spironolactone and thus has a diuretic effect that other progestins do not, Gloria Bachmann, M.D., reported at the annual meeting of the American College of Obstetricians and Gynecologists.
Drospirenone is used in an FDA-approved OC (Yasmin, manufactured by Berlex) in a formulation of 30 mcg of ethinyl estradiol (EE) and 3 mg of drospirenone given in the typical OC regimen of 21 days, followed by 7 hormone-free days.
But the newer low-dose formulation (20 mcg of EE/3 mg drospirenone) given over a 24-day period with only 4 hormone-free days can significantly reduce symptoms of premenstrual dysphoric disorder (PMDD), compared with placebo, said Dr. Bachmann, associate dean for women's health and professor of obstetrics and gynecology at Robert Wood Johnson Medical School, New Brunswick, N.J.
“In the usual OC cycle of 21 hormone days and 7 days off, women begin to get symptomatic even before the pill-free interval because their ovaries are not totally suppressed,” she said in an interview. “By giving an extended number of days of hormone, you have better ovarian suppression and thus fewer symptoms during the shorter pill-free interval.”
Dr. Bachmann presented a double-blind study, sponsored by Berlex, in which 83 women with PMDD were randomized to either the low-dose drospirenone-based extended OC regimen (42 women) or placebo (41 women) for three cycles of treatment followed by a washout cycle. The women then crossed over to the other arm of treatment for another three cycles.
PMDD symptoms were assessed using the Daily Record of Severity of Problems (DRSP) scale, which includes 21 symptoms and 3 measures of functional impairment.
Active treatment was significantly more effective than placebo in relieving emotional and physical symptoms of PMDD, and the effects were similar to those seen when PMDD is treated with selective serotonin reuptake inhibitors (SSRIs), Dr. Bachmann commented during the meeting.
“If you're deciding between an SSRI and an OC [to treat women with PMDD], you have the added benefit of birth control. You're actually improving the gynecologic health of women as well, so it's a win-win situation,” she said.