A systematic review with a network meta-analysis of topical treatments for acne
Acne vulgaris is a skin condition that very commonly affects teenagers but also many adults. The impact of acne on quality of life, especially psychologically, can be great. The condition is largely managed in primary care. Guidelines on acne recommend combination topical preparations as first line treatment. In practice however, topical preparations containing only one drug substance are widely prescribed. Failure of topical treatments means that patients frequently progress to long courses of oral antibiotics, which contribute to antibiotic resistance.
Patients, carers and healthcare professionals would like to know what the best topical treatment for acne is. Currently however, there are no systematic reviews providing direct comparisons of the most commonly prescribed topical treatments, most likely because trials have not been undertaken to directly compare all relevant treatments. Network-meta-analysis can overcome this limitation by using all available data to build a network of direct and indirect comparisons to obtain estimates of effectiveness of treatments.
By carrying out a systematic review with network meta-analysis, we aim to identify which of the topical preparations, available on prescription in the UK or recommended in the NICE acne clinical knowledge summary or European acne guidelines are most effective and best tolerated.
Electronic searches were conducted in Cochrane CENTRAL, MEDLINE, EMBASE and WHO ICTRP. Two reviewers independently assessed titles, abstracts, and full papers. Studies were eligible for inclusion if they were randomised controlled trials assessing protocol specified topical preparations for the treatment of mild to moderate acne in male or female patients. These preparations include: azelaic acid, adapalene, adapalene+benzoyl peroxide (BPO), BPO, BPO+clindamycin, clindamycin, clindamycin+zinc, erythromycin+zinc, isotretinoin+erythromycin, tretinoin, tretinoin+clindamycin, tretinoin+erythromycin. Primary outcomes are: participant expressed self-reported improvement in acne and withdrawal from study/stopping study medication due to adverse events. Secondary outcomes are: change in lesion count from baseline as assessed by an investigator; proportion of participants rated 'clear' or 'almost clear' on the Investigator Global Assessment (IGA) scale of acne severity; proportion of participants rated as having at least two grades improvement from baseline on the IGA change in quality of life from baseline; reduction in P. acnes strains (total and resistant); number of adverse events; patient satisfaction with treatment.
Data extraction and risk of bias assessment are currently in progress, being performed by one researcher and checked by a second.
Our search yielded 4077 records in total of which 2415 were unique. Of these records, 2086 were ineligible after title and abstract review. Of the remaining 329 records, 162 were excluded after assessment of full papers. Ultimately 167 articles representing 76 studies were included in the review.
Results will be available at the time of SAPCSW 2020
Providing evidence on most effective topical treatments may help avoid oral antibiotic use for this common condition.