Randomized controlled study of a cosmetic treatment for mild acne B. Capitanio, J. L. Sinagra, R. B. Weller,* C. Brown† and E. Berardesca San Gallicano Dermatological Institute, Rome, Italy; *University Department of Dermatology, Lauriston Place, Edinburgh, UK; and †The Mentholatum Company Ltd, Glasgow, UK doi:10.1111/j.1365-2230.2011.04317.x Summary Background. Cosmetic products are not tested with the same rigour as medical treatments, but recent high-quality studies have shown significant reductions in changes of skin ageing with use of cosmetic antiageing products. Aim. To test whether a cosmetic ‘anti-spot’ two-step treatment containing a complex of seaweed-derived oligosaccharide and zinc would produce a significant improvement in mild acne. Methods. A double-blind, vehicle-controlled trial of this treatment was performed for 8 weeks on 60 age-matched participants with mild acne. They were divided into two groups: 30 participants were treated with vehicle control and 30 with the active treatment containing a seaweed-derived oligosaccharide complexed with 0.1% zinc pyrrolidone. Results. After 8 weeks, both groups had a reduction in comedones, papules and pustules, and this was significantly greater in the active than control group at 2, 4 and 8 weeks. Conclusions. Cosmetic products may offer some benefit for mild acne and still meet the requirements of the European Cosmetic Directive. In particular, the seaweed- derived oligosaccharide complexed with 0.1% zinc pyrrolidone used in this study produced a significant reduction in acne vs. a control treatment. Cosmetic companies should conduct blinded controlled trials of their product’s efficacy and publish the results. Introduction The effectiveness of cosmetic products on the skin is rarely tested with the same rigour as pharmacological agents. 1 The rather ambiguous wording of the Euro- pean Cosmetics Directive has dissuaded the industry from testing their products in a blinded, controlled fashion, but this has now started to change. Two methodologically rigorous, controlled, double-blinded trials of ‘antiageing’ cosmetic products have recently been published. Both agents reduced wrinkles, one more effectively than a vehicle control, 2 and the other more effectively than a pharmacologically active compara- tor. 3 Neither product has been reclassified as a drug, and there is now growing expectation and pressure that a higher standard of proof should be expected from cosmetics than ambiguous advertising claims. 1,4,5 Acne is a very common disorder of the pilosebaceous apparatus, in which seborrhoea, poral occlusion and activity of the bacterium Propionibacterium acnes leads to the formation of papules, pustules and comedones. 6 The condition varies in severity, and most patients with mild acne never seek medical attention. Medical treatments for these milder degrees of acne include topical anti- biotics, benzyl peroxide and topical retinoids. Acidic polysaccharides derived from green tea (Camellia sinen- sis) have also been shown to reduce bacterial adhesion of P. acnes. 7 We describe a double blinded vehicle-controlled, study of a cosmetic ‘anti-spot’ preparation containing Correspondence: Dr Richard Weller, University Department of Dermatology, Lauriston Building, Lauriston Place, Edinburgh EH3 9HA, UK E-mail: r.weller@ed.ac.uk Conflict of interest: RBW has received consultancy fees from Mentholatum. CB is an employee of Mentholatum. The other authors have no conflicts of interest to declare. Accepted for publication 2 November 2011 Clinical dermatology • Original article CED Clinical and Experimental Dermatology Ó The Author(s) 346 CED Ó 2012 British Association of Dermatologists • Clinical and Experimental Dermatology, 37, 346–349