Verdeso (Desonide Topical) - Description and Clinical Pharmacology

Description

Verdeso™ Foam is a petrolatum-based emulsion aerosol foam containing the active ingredient desonide, a low-potency topical corticosteroid.

Chemically, desonide is (11β,16α)-11,21-dihydroxy-16,17-[(1-methylethylidene)-bis(oxy)]-pregna-1,4-diene-3,20-dione.

The structural formula of desonide is represented below:

Desonide has a molecular formula of C₂₄H₃₂O₆ and a molecular weight of 416.51. Desonide is a white powder or crystal that is practically insoluble in water, sparingly soluble in ethanol and in acetone, and soluble in chloroform. Each gram of Verdeso Foam contains 0.5 mg desonide. The foam also contains anhydrous citric acid USP, cetyl alcohol NF, cyclomethicone NF, isopropyl myristate NF, light mineral oil NF, white petrolatum USP, polyoxyl 20 cetostearyl ether NF, potassium citrate (monohydrate) USP, propylene glycol USP, purified water USP, sorbitan monolaurate NF, and phenoxyethanol NF as a preservative.

Verdeso Foam is dispensed from an aluminum can pressurized with a hydrocarbon (propane/butane) propellant.

Clinical Pharmacology

Topical corticosteroids share anti-inflammatory, anti-pruritic, and vasoconstrictive actions.

The mechanism of anti-inflammatory activity of the topical corticosteroids is unclear. However, corticosteroids are thought to act by the induction of phospholipase A₂ inhibitory proteins, collectively called lipocortins. It is postulated that these proteins control the biosynthesis of potent mediators of inflammation such as prostaglandins and leukotrienes by inhibiting the release of their common precursor arachidonic acid. Arachidonic acid is released from membrane phospholipids by phospholipase A₂.

Pharmacokinetics: Topical corticosteroids can be absorbed from intact healthy skin. The extent of percutaneous absorption of topical corticosteroids is determined by many factors, including the product formulation and the integrity of the epidermal barrier. Occlusion, inflammation and/or other disease processes in the skin may also increase percutaneous absorption. The use of pharmacodynamic endpoints for assessing the systemic exposure of topical corticosteroids may be necessary due to the fact that circulating levels are often below the level of detection. Once absorbed through the skin, topical corticosteroids are handled through pharmacokinetic pathways similar to systemically administered corticosteroids. They are metabolized, primarily in the liver, and are then excreted by the kidneys. Some corticosteroids and their metabolites are also excreted in the bile.

In a controlled pharmacokinetic study, 3 of 75 (4%) pediatric patients with mild to moderate atopic dermatitis covering at least 25% body surface area, who applied Verdeso Foam twice daily, experienced reversible suppression of the adrenal glands following 4 weeks of therapy (see Pediatric use).

CLINICAL STUDIES:

In a double-blind, randomized study of 581 patients ages 3 months to 17 years old, with mild to moderate atopic dermatitis, Verdeso Foam was applied twice daily for 4 weeks. Success was defined as the proportion of patients who had all of the following: an Investigator’s Static Global Assessment (ISGA) score of clear or almost clear, a minimum improvement in the 5 point ISGA score of 2 grades from Baseline to Week 4, and a score of absent or minimal for both erythema and induration/papulation at Week 4. The results of this study are presented in the table below.

	Verdeso Foam	Vehicle Foam
Number of Patients	387	194
Patients Achieving Success	152 (39%)	18 (9%)