Mometasone furoate pharmacokinetics and molecular data

Pharmacokinetics
Overview Absorption Potency Effects on HPA axis Pediatric patients

Overview
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. Return to top

Absorption
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 Mometasone Furoate Lotion 0.1% (Mometasone furoate topical solution USP) enters the circulation after 8 hours of contact on normal skin without occlusion. A similar minimal degree of absorption of the corticosteroid from the lotion formulation would be anticipated. Inflammation and/or other disease processes in the skin may increase percutaneous absorption. Return to top

Potency
Studies performed with Mometasone Furoate Lotion 0.1% indicate that it is in the medium range of potency as compared with other topical corticosteroids. Return to top

Effects on HPA axis
In a study evaluating the effects of Mometasone furoate lotion on the hypothalamic-pituitary-adrenal (HPA) axis, 15 mL were applied without occlusion twice daily (30 mL per day) for 7 days to four adult patients with scalp and body psoriasis. At the end of treatment, the plasma cortisol levels for each of the four patients remained within the normal range and changed little from baseline. Return to top

Pediatric patients
Sixty-five pediatric patients ages 6 to 23 months, with atopic dermatitis, were enrolled in an open-label, hypothalamic-pituitary-adrenal (HPA) axis safety study. Mometasone Furoate Lotion 0.1% was applied once daily for approximately 3 weeks over a mean body surface area of 40% (range 16% to 90%). In approximately 29% of patients who showed normal adrenal function by Cortrosyn test before starting treatment, adrenal suppression was observed at the end of treatment with Mometasone Furoate Lotion 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 one patient, using these same criteria. Return to top