Adverse events that are associated with the selective estrogen receptor modulator levormeloxifene in an aborted phase III osteoporosis treatment study

OBJECTIVE: Selective estrogen receptor modulators are novel compounds that bind to the estrogen receptor and have mixed agonistic and antagonistic activities. Recently, an increase in urinary incontinence has been reported with hormone replacement therapy use. A decrease in surgical procedures for pelvic floor relaxation has been recently reported with raloxifene, a selective estrogen receptor modulator that is not uterotropic. Levormeloxifene is a selective estrogen receptor modulator that was developed for the purpose of the treatment and prevention of postmenopausal osteoporosis. STUDY DESIGN: This was a multicentered prospective study of healthy women aged greater than or equal to65 years with osteoporosis who were randomized to blindly receive placebo or levormeloxifene 0.5 mg or 1.25 mg daily as part of a planned 3-year osteoporosis treatment study. Multiple medical and gynecologic evaluations were performed. Adverse events were reported to investigators and coded with the use of World Health Organization terminology. This study was halted after 10 months because of the large number of gynecologic and other adverse events. RESULTS: Among 2924 women who were studied, those women who were treated with levormeloxifene had a marked increase compared with placebo in leukorrhea (30% vs 3%), increased endometrial thickness on ultrasound scan (19% vs 1%), enlarged uterus (17% vs 3%), uterovaginal prolapse (7% vs 2%), urinary incontinence (17% vs 4%), increased micturition frequency (9% vs 4%), lower abdominal pain (17% vs 6%), hot flushes (10% vs 3%), and leg cramps (6% vs 0.8%). All of these differences were highly statistically significant with a probability value of .0001 for each. CONCLUSION: Levormeloxifene results in multiple adverse gynecologic and other events in postmenopausal women with osteoporosis.