Objective: To compare ospemifene and raloxifene regarding their effects on hormones, lipids, genital tract, and tolerability in postmenopausal women.
Design: A randomized, double-blind study in which 118 healthy postmenopausal women received 30 (n = 29), 60 (n = 30), or 90 mg (n = 30) of ospemifene or 60 mg (n = 29) of raloxifene for 3 months.
Results: There were no significant differences in the baseline characteristics between study groups. In comparison with raloxifene, follicle-stimulating hormone levels decreased significantly more in the 90-mg ospemifene group and sex hormone-binding globulin levels increased more in all ospemifene groups. Total cholesterol and low-density lipoprotein cholesterol levels decreased more in raloxifene than in ospemifene groups, although the difference in low-density lipoprotein cholesterol between 90-mg ospemifene and raloxifene was not significant. Endometrial thickness did not change in any study group and endometrial biopsies showed atrophy in the majority of subjects at 3 months. All ospemifene groups demonstrated a clear estrogenic effect on the vaginal epithelium, as seen in Pap smears. This was in sharp contrast to the raloxifene group, which had no effect on the vaginal epithelium. Kupperman index decreased in all study groups during treatment. The adverse events were mild, mainly single cases, and no clustering of events was observed. There were no clinically significant abnormal findings in laboratory safety parameters.
Conclusions: Ospemifene, at the dose of 90 mg/day, was more estrogenic than raloxifene, as shown by changes in serum follicle-stimulating hormone and sex hormone-binding globulin levels. Neither agent stimulated endometrium, but in contrast to raloxifene, ospemifene had a clear estrogenic effect in the vagina. Further studies with ospemifene are needed in subjects with vaginal atrophy.
This article demonstrates the differences in the hormonal profile between two selective estrogen-receptor modulators, ospemifene and raloxifene.
From 1Hormos Medical Corporation, Turku, Finland; 2PSR Consulting Ltd, Helsinki, Finland; 3Department of Anatomy, Institute of Biomedicine, University of Turku, Turku, Finland; 4Department of Internal Medicine, Division of Hematology and Oncology, Cancer Center, University of California, Sacramento, California, USA; 5Department of Obstetrics and Gynecology, Turku University Central Hospital, Turku Finland; 6Lääkäriasema Jaarli, Hämeenlinna, Finland; 7Koskiklinikka, Tampere, Finland; 8Center for Reproductive and Developmental Medicine, University of Turku, Turku Finland; and 9Department of Obstetrics and Gynecology, Helsinki University Central Hospital, Helsinki, Finland.
Received January 21, 2004; revised and accepted May 5, 2004.
The study was supported by a research grant from Hormos Medical Corporation.
Address correspondence to: Risto Erkkola, Department of Obstetrics and Gynecology, Turku University Central Hospital, PO Box 52, 20521 Turku. E-mail: firstname.lastname@example.org