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Abstract Psoriasis is a chronic immune-mediated inflammatory skin disease with a worldwide prevalence of 2%. Plaque psoriasis is considered the most prevalent type reported in more than 90% of psoriasis cases. The classic psoriatic lesions remain the main hallmark of the disease; with well-demarcated, symmetric, and erythematous plaques overlying whitish-silvery scales. Plaques are typically redundant on the trunk, buttocks, and extremities; however, the scalp is usually the most common involved body site throughout the course of the disease. For decades, topical corticosteroids including betamethasone dipropionate remained the mainstay in the management of mild to moderate psoriasis, however, keratolytic agents, vitamin D analogs, retinoids, dithranol as well as tar-based therapies have also been used as an adjunctive therapy; they have been formulated into a wide range of formulations, including; shampoos, alcohol‐based lotions, emulsions, creams, ointments, gels, and foams. The anti-psoriatic action of topical corticosteroids is attributed to its powerful anti-inflammatory properties exerted by blocking inflammatory mediators as well as immunosuppressive actions through suppressing T cell-mediated hypersensitivity reactions. Topical corticosteroids also possess strong antiproliferative effects on epidermal cell turnover and vasoconstrictive actions on blood vessels.However, skin atrophy, striae, rosacea, purpura, delayed wound healing, hypertrichosis and pigment alteration are among the side effects associated with topical corticosteroids prolonged use. Salicylic acid, a keratolytic agent, is used in combination with betamethasone dipropionate because of its ability to remove scales from hyperkeratotic plaques and enhance the absorption of topical corticosteroids. However, salicylic acid might irritate non‐hyperkeratotic skin and it shouldn’t be applied to more than 20% of body surface area to avoid the risk of salicylism toxicity symptoms including metabolic acidosis, tinnitus, nausea, vomiting,and central nervous system associated symptoms. Cubosomes are discrete nanovesicles bi-continuous cubic phase liquid crystals composed of biodegradable lipid and water, with a powerful ability to solubilize and encapsulate hydrophilic, hydrophobic, and amphiphilic molecules, outstanding biocompatibility and bio-adhesive properties. Cubosomes have gained a rising interest in topical preparations since they are considered a good candidate for skin transport due to their similarity with human skin layers besides their enhanced skin penetration properties. They are also characterized by small pore size making them ideal for controlled release, in addition, to their high internal surface area, drug payloads, heat stability, and ability to moisturize the skin. |