Objective: To examine the effect of intravaginal dehydroepiandrosterone (DHEA) on pain at sexual activity (dyspareunia) identified as the most bothersome symptom of vaginal atrophy in postmenopausal women at both screening and day 1.
Methods: This prospective, randomized, double-blind and placebo-controlled phase III clinical trial studied the effect of prasterone (DHEA) applied locally in the vagina on the severity of dyspareunia in 114 postmenopausal women who had identified dyspareunia as their most bothersome symptom of vaginal atrophy, while meeting the criteria for superficial cells ≤ 5% and pH > 5.0 at both screening and day 1.
Results: At the standard duration of 12 weeks of treatment, increasing doses of 0.25%, 0.5% and 1.0% DHEA decreased the percentage of parabasal cells by 48.6 ± 6.78%, 42.4 ± 7.36% and 54.9 ± 6.60% (p < 0.0001 vs. placebo for all) with no change with placebo (p = 0.769). The effects on superficial cells and pH were also highly significant compared to placebo at all DHEA doses. The severity score of pain at sexual activity decreased by 0.5, 1.4, 1.6 and 1.4 units in the placebo and 0.25%, 0.5% and 1.0% DHEA groups, respectively, with the p value of differences from placebo ranging from 0.0017 to < 0.0001.
Conclusions: Intravaginal DHEA, through local estrogen and androgen formation, causes a rapid and highly efficient effect on pain at sexual activity without systemic exposure of the other tissues, thus avoiding the recently reported systemic effects of estrogens.