Elocon (Mometasone Furoate Topical) - Description and Clinical Pharmacology

For Dermatologic Use Only
Not for Ophthalmic Use

DESCRIPTION

ELOCON^® (mometasone furoate ointment, USP) Ointment 0.1% contains mometasone furoate, USP for dermatologic use. Mometasone furoate is a synthetic corticosteroid with anti-inflammatory activity.

Chemically, mometasone furoate is 9α,21-Dichloro-11β,17-dihydroxy-16α-methyl-pregna-1,4-diene-3,20-dione 17-(2-furoate), with the empirical formula C₂₇H₃₀Cl₂O₆, a molecular weight of 521.4 and the following structural formula:

Mometasone furoate is a white to off-white powder practically insoluble in water, slightly soluble in octanol, and moderately soluble in ethyl alcohol.

Each gram contains: 1 mg mometasone furoate, USP in an ointment base of hexylene glycol; phosphoric acid; propylene glycol stearate (55% monoester); white wax; white petrolatum; and purified water.

CLINICAL PHARMACOLOGY

Like other topical corticosteroids, mometasone furoate has anti-inflammatory, anti-pruritic, and vasoconstrictive properties. The mechanism of the anti-inflammatory activity of the topical steroids, in general, 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

The extent of percutaneous absorption of topical corticosteroids is determined by many factors including the vehicle and the integrity of the epidermal barrier. Occlusive dressings with hydrocortisone for up to 24 hours have not been demonstrated to increase penetration; however, occlusion of hydrocortisone for 96 hours markedly enhances penetration. Studies in humans indicate that approximately 0.7% of the applied dose of ELOCON Ointment 0.1% enters the circulation after 8 hours of contact on normal skin without occlusion. Inflammation and/or other disease processes in the skin may increase percutaneous absorption.

Studies performed with ELOCON Ointment 0.1% indicate that it is in the medium range of potency as compared with other topical corticosteroids.

In a study evaluating the effects of mometasone furoate ointment on the hypothalamic-pituitary-adrenal (HPA) axis, 15 grams were applied twice daily for 7 days to six adult patients with psoriasis or atopic dermatitis. The ointment was applied without occlusion to at least 30% of the body surface. The results show that the drug caused a slight lowering of adrenal corticosteroid secretion.

In a pediatric trial, 24 atopic dermatitis patients, of which 19 patients were age 2 to 12 years, were treated with ELOCON Cream 0.1% once daily. The majority of patients cleared within 3 weeks.

Sixty-three pediatric patients ages 6 to 23 months, with atopic dermatitis, were enrolled in an open-label, hypothalamic-pituitary-adrenal (HPA) axis safety study. ELOCON Ointment 0.1% was applied once daily for approximately 3 weeks over a mean body surface area of 39% (range 15% to 99%). In approximately 27% of patients who showed normal adrenal fuction by Cortrosyn test before starting treatment, adrenal suppression was observed at the end of treatment with ELOCON Ointment 0.1%. The criteria for suppression were: basal cortisol level of ≤5 mcg/dL, 30-minute post-stimulation level of ≤18 mcg/dL, or an increase of <7 mcg/dL. Follow-up testing 2 to 4 weeks after stopping treatment, available for 8 of the patients, demonstrated suppressed HPA axis function in 3 patients, using these same criteria.