RF04 Oral spironolactone for adult female acne (SAFA): a multicentre, double-blind, randomized trial

Abstract

Abstract Acne is common and results in significant burden and patients with acne frequently receive prolonged oral antibiotics leading to antimicrobial resistance. Oral spironolactone is prescribed for acne, although there is a paucity of evidence on its effectiveness. The aim of this pragmatic parallel, double-blind, superiority trial was to assess the effectiveness of systemic spironolactone for acne in adult women. Participants were identified through primary and secondary health care and through community and social media advertising. Women aged ≥ 18 years with facial acne for at least 6 months, judged to warrant oral antibiotics, were invited to participate. Consented recruits were randomized 1 : 1 to either 50 mg daily spironolactone or matched placebo until week 6, increasing to 100 mg daily spironolactone or placebo until week 24. Topical treatment could be continued. The primary outcome was Acne-Specific Quality of Life (Acne-QoL) symptom subscale score at week 12. Secondary outcomes included Acne-QoL at week 24, participant self-assessed improvement, Investigator’s Global Assessment (IGA) and adverse effects. Of 1267 women assessed, 410 were randomized (201 intervention, 209 control) and 342 were included in the primary analysis. Baseline mean (SD) age was 29.2 (7.2) years, 7.9% (n = 28/356) were of a non-White background, 46% had mild acne, 40% moderate acne and 13% severe acne (IGA classified). Eighty-three per cent used topical treatments. Over 95% of patients in both groups tolerated treatment and increased dosage. Mean (SD) Acne-QoL symptom scores at baseline and week 12 were 13.2 (4.9) and 19.2 (6.1) for spironolactone and 12.9 (4.5) and 17.8 (5.6) for placebo, respectively {difference favouring spironolactone 1.27 [95% confidence interval (CI) 0.07–2.46]}. Scores at week 24 were 21.2 (5.9) for spironolactone and 17.4 (5.8) for placebo [difference 3.45 (95% CI 2.16–4.75)]. Secondary outcomes also favoured spironolactone at week 12, with greater differences at week 24. More participants on spironolactone reported acne improvement than those on placebo. At week 12, this difference was not statistically significant [72.2% vs. 67.9%; odds ratio (OR) 1.16, 95% CI 0.70–1.91], but at week 24, it was significant (81.9% vs. 63.3%; OR 2.72, 95% CI 1.50–4.93). Treatment success (IGA classified) at week 12 was 31/201 on spironolactone and 9/209 on placebo (OR 5.18, 95% CI 2.18–12.28). Adverse reactions were not serious and were similar between groups, although more headaches were reported by those on spironolactone (20.4% vs. 12.0%; P = 0.02). Spironolactone improved outcomes vs. placebo, with greater differences at week 24 than at week 12. This study supports spironolactone as a potential alternative to oral antibiotics for acne in adult women.