Abstract Objective To evaluate the efficacy and safety of ospemifene, a novel selective oestrogen receptor modulator, in the treatment of vaginal dryness in postmenopausal women with vulvovaginal atrophy (VVA). Study design A 12 week, multicentre, randomised, double-blind, parallel-group phase III study of women (40–80 years) with VVA and self-reported vaginal dryness as their most bothersome symptom. Main outcome measures The co-primary efficacy endpoints were the change from baseline to Week 12 in (1) percentage of parabasal cells in the maturation index (MI), (2) percentage of superficial cells in the MI, (3) vaginal pH, and (4) severity of vaginal dryness. Safety assessments included physical examination, cervical Papanicolaou test and clinical laboratory analyses. Endometrial thickness and histology was also assessed. Results A total of 314 women were randomised to once-daily ospemifene 60 mg/day ( n = 160) or placebo ( n = 154). Significant improvements in the percentages of parabasal and superficial cells in the MI and vaginal pH were observed with ospemifene compared with placebo ( p < 0.001 for all parameters). The mean change from baseline in severity score of vaginal dryness reported by women receiving ospemifene compared with those receiving placebo approached statistical significance ( p = 0.080). Improvements in each of the four co-primary endpoints with ospemifene were statistically significant compared to placebo in the per protocol population. The majority of treatment-emergent adverse events were considered mild to moderate in severity. Conclusions Once-daily oral ospemifene 60 mg was effective for the treatment of VVA in postmenopausal women with vaginal dryness.