Objective: To compare the effects of continuous combined conjugated equine estrogens plus medroxyprogesterone acetate (CEE/MPA) with those of tibolone on symptom control, bleeding pattern, lipid profile and tolerability in postmenopausal women.
Methods: This was a randomized, open-label, parallel-group, multicenter study. Generally healthy postmenopausal women with an intact uterus and no contraindications to hormone replacement therapy (HRT) or tibolone were enrolled. Each subject was randomly assigned to receive CEE/MPA 0.625 mg-5.0 mg or tibolone 2.5 mg daily for 13 treatment cycles, each of 28 days.
Results: A total of 85 subjects were enrolled and received at least one dose of study medication, of which 76 (89.4%) subjects completed the study (n = 40, CEE/MPA; n = 36, tibolone). The incidence of postmenopausal symptoms decreased significantly over time in both treatment groups, compared with baseline, including significant decreases in the incidence of urogenital and sexual health symptoms. Significant differences in symptom control (other than hot flushes) were observed between treatment groups in a few different cycles for different symptoms, but no consistent or clinically significant trends were observed. No statistically significant differences in the incidence of bleeding were observed between treatment groups after cycle 4. Significant decreases in total cholesterol (5.6%) and low-density lipoprotein (LDL) cholesterol (7.5%) were observed at cycle 13, compared with baseline, in the CEE/MPA group, and significant decreases in high-density lipoprotein (HDL) cholesterol (8.5%) and triglycerides (13.7%) were observed at cycle 13, compared with baseline, in the tibolone group. Significant weight gain was observed at cycle 13 in the tibolone group (3.05 kg), compared with the CEE/MPA group (0.96 kg). The incidences of adverse events were similar in both treatment groups.
Conclusions: Women treated with CEE/MPA or tibolone showed significant improvement of postmenopausal symptoms, including urogenital and sexual health symptoms, and had similar bleeding patterns after four cycles of therapy. CEE/MPA and tibolone each induced a different mix of changes in the lipid profile.