Treatment considerations for inflammatory acne: clinical evidence for adapalene 0.1% in combination therapies

Acne vulgaris is an exceptionally common, chronic, and recurring disease. It involves multiple etiological factors including follicular hyperkeratinization, increased sebum production, Propionibacterium acnes proliferation, and inflammation. Presently, oral isotretinoin is the only single agent that is effective against all 4 major pathophysiologic features. However, this drug is also responsible for several serious side effects, including teratogenicity. Therefore, it should be used in only the most severe cases and alternative treatment approaches for inflammatory acne, such as initial combination therapy, should be considered first. Combination therapy in inflammatory acne simultaneously targets multiple pathogenic factors. Current guidelines recommend early initiation of combination therapy with a topical retinoid and antimicrobials for mild to moderate inflammatory acne and topical retinoids with oral antibiotics (with or without the use of benzoyl peroxide) for moderate to severe cases of acne, followed by maintenance therapy with topical retinoids. This review evaluates the rationale and clinical evidence for the use of adapalene in combination therapy for inflammatory acne.