Combination Therapy in Psoriasis An Evidence-Based Review

Background Psoriasis is a chronic, systemic, inflammatory condition for which a variety of treatment modalities exist. Combinations of therapies are used often in clinical practice to enhance efficacy and reduce drug toxicities. Purpose The purpose of this review is to assess the literature on the efficacy and safety of combination therapy in the treatment of psoriasis. Methods MEDLINE was reviewed to identify English-language publications from 1966 to 2011 examining combination therapy in psoriasis. Fifty-three articles met inclusion criteria and were included in this review. Randomized controlled trials addressing various combinations of treatment modalities for psoriasis were included. Data from these clinical studies were summarized and the outcomes were discussed. Results Large-scale, randomized controlled trials investigating the use of various combination therapies in psoriasis are limited. The strongest data support the use of combinations of vitamin D derivatives and corticosteroids as topical combinations and, to a lesser extent, the combination of other topical agents. Phototherapy and topical vitamin D derivatives as well as phototherapy in combination with oral retinoids are well supported in the literature. Combinations of systemic medications, though often used clinically, have little data to support their efficacy or safety. Limitations Our data were limited by the small number of clinical trials examining the multiple available combinations that are used in clinical practice. Conclusions The use of combination treatments falls within the standard of care for psoriasis, even if these combinations have not been extensively studied in clinical trials.