SAN FRANCISCO — An investigational form of depot medroxy-progesterone acetate is as effective as leuprolide for the treatment of endometriosis-associated pelvic pain, but it's significantly safer and better tolerated, Anthony A. Luciano, M.D., said at the annual meeting of the American Association of Gynecologic Laparoscopists.
The new formulation, called DMPA-SC (depot medroxyprogesterone acetate-subcutaneous), resulted in significantly smaller losses in bone mineral density (BMD) and significantly fewer menopausal symptoms than did leuprolide in the prospective, randomized, investigator-blinded study, said Dr. Luciano of the University of Connecticut in Farmington.
DMPA-SC has not been approved by the Food and Drug Administration. The study was funded by its manufacturer, Pharmacia Upjohn, a company that has become part of Pfizer Inc. Dr. Luciano acknowledged receiving consulting and honorarium support from Pfizer.
During the study, 274 women aged 18-49 years who had diagnoses of endometriosis-associated pelvic pain received 6 months of treatment with either DMPA-SC (104 mg every 3 months) or leuprolide (11.25 mg IM every 3 months). They were followed for an additional 12 months after completing treatment.
Patients rated their pain in five categories: dysmenorrhea, dyspareunia, pelvic pain, pelvic tenderness, and induration. Investigators used the Kupperman Index—a composite score involving 11 menopausal symptoms—to assess hypoestrogenemia.
Both groups experienced substantial improvements in their pelvic pain, both at the end of treatment and continuing 12 months later, with no significant differences between the two groups.
Both groups showed some BMD declines at the end of treatment, but the mean losses were significantly less for women taking DMPA-SC than for women taking leuprolide in both the femur (0.3% vs. 1.65%) and the spine (1.1% vs. 3.95%).
Those who'd been taking DMPA-SC saw their BMD return to pretreatment levels 12 months after discontinuing treatment, whereas those who had been taking leuprolide showed continued BMD losses: 1.3% in the femur and 1.7% in the spine.
Women taking leuprolide had significant increases in Kupperman Index scores; those taking DMPA-SC showed no increase. Between the second and sixth month of treatment, women taking leuprolide experienced an average of two to three hot flashes per day. Women on DMPA-SC had almost no hot flashes. A significantly higher percentage of leuprolide patients had estradiol levels lower than 41 pg/mL (77% vs. 33%).
Adverse events seen more often in the DMPA-SC group were injection-site reactions (6.9% vs. 0%) and intermenstrual bleeding (5.4% vs 0.7%).