Objective: To evaluate the efficacy of ultra-low-dose 10-microgram 17beta-estradiol (E2) vaginal tablets for treatment of vaginal atrophy.
Methods: Postmenopausal women (N=309) were randomly assigned to 10-microgram E2 or placebo vaginal tablets for 52 weeks in a multicenter, double-blind study. Primary efficacy endpoints included change from baseline to week 12 in vaginal cytology, vaginal pH, and most bothersome urogenital symptoms score. Grading of vaginal health was a secondary efficacy assessment. Safety assessments included endometrial biopsy, physical and gynecologic examinations, and recording adverse events.
Results: At week 12, the change from baseline for 10 micrograms E2 compared with placebo demonstrated significant improvement in vaginal Maturation Index (proportion of parabasal cells: -37% compared with -9%; superficial cells: 13% compared with 4%; intermediate cells: 24% compared with 5%; P<.001 for each), Maturation Value (25.0 compared with 6.5, P<.001), grading of vaginal health (-0.91 compared with -0.51, P<.001), vaginal pH grade (-1.3 compared with -0.4, P<.001), and most bothersome symptoms score (-1.23 compared with -0.87, P=.003). For each component of vaginal Maturation Index, vaginal Maturation Value, grading of vaginal health, and vaginal pH, treatment effects were statistically different from placebo after 2 weeks of treatment. For most bothersome symptoms, treatment effect became apparent after 4 weeks and reached statistical significance at week 8 of therapy. All treatment effects were statistically significant at week 52. There were no major safety findings regarding physical, gynecologic, or laboratory assessments.
Conclusion: After 12 weeks of treatment, an ultra-low-dose 10-microgram E2 vaginal tablet, compared with placebo, demonstrated significant improvement for the primary endpoints: vaginal cytology and pH and most bothersome urogenital symptoms score.
Clinical trial registration: ClinicalTrials.gov, http://clinicaltrials.gov, NCT00108849
Level of evidence: I.