It has been known for decades that the sequential topical use of the vitamin D3 analog calcipotriene (Cal) and the corticosteroid betamethasone dipropionate (BD) has been shown to provide greater benefit than either monotherapy.1-3 However, early on, the use of this combination was associated with patient inconvenience. More importantly, chemical instability of these two molecules when applied one after another makes calcipotriene not compatible with topical corticosteroids; therefore, patients had to apply the medications at different times.4
Innovation in formulation science allowed for the development of fixed combination topical formulations of Cal/BD for improved patient convenience and, presumably, adherence. Calcipotriene and betamethasone dipropionate aerosol foam 0.005%/0.064% is one of the more recent formulations to reach the market.
Recent findings are adding to our understanding of the clinical benefits of topical Cal/BD foam for psoriasis. An analysis of various topical therapies for psoriasis found that all assessed therapies reduced epidermal thickness and improved targeted Psoriasis Area and Severity Index (PASI) scores. However, Cal/BD foam was the only treatment shown to completely suppress CD8+ T-cell influx
in the epidermis and dermis and to reduce CD8 + IFN-γ+ cell counts, and significantly reduce the number of IL-17 expressing, MPO+ neutrophils.5 Microscopic evaluations showed that, compared to corticosteroid alone, Cal/BD foam was associated with significantly greater reductions in microscopic epidermal thickness by week 4, and there were fewer telangiectasias in combination-treated lesions than clobetasol-treated lesions.6
