Like other topical corticosteroids, CLOBEX® (clobetasol propionate) Lotion,
0.05% has anti-inflammatory, antipruritic, 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 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 phos-pholipase A2.
Pharmacokinetics
The extent of percutaneous absorption of topical corticosteroids is determined
by many factors, including the vehicle, the integrity of the epidermal barrier
and occlusion. For example, occlusive dressing with hydrocortisone for up to
24 hours has not been demonstrated to increase penetration; however, occlusion
of hydrocortisone for 96 hours markedly enhances penetration. Topical corticosteroids
can be absorbed from normal intact skin. Inflammation and other disease processes
in the skin may increase percutaneous absorption.
There are no human data regarding the distribution of corticosteroids to body
organs following topical application. Nevertheless, once absorbed through the
skin, topical corticosteroids are handled through pharmacokinetic pathways similar
to systematically administered corticosteroids. Due to the fact that circulating
levels are usually below the level of detection, the use of pharmacodynamic
endpoints for assessing the systemic exposure of topical corticosteroids is
necessary. They are metabolized, primarily in the liver, and are then excreted
by the kidneys. In addition, some corticosteroids and their metabolites are
also excreted in the bile.
CLOBEX® (clobetasol propionate) Lotion, 0.05% is in the super-high range
of potency as compared with other topical corticosteroids in vasoconstrictor
studies.
In studies evaluating the potential for hypothalamic-pituitary-adrenal (HPA)
axis suppression, CLOBEX® Lotion (clobetasol propionate lotion) , 0.05% demonstrated rates of suppression
that were numerically higher than those of a clobetasol propionate 0.05% cream
(Temovate E® Emollient, 0.05%), (See PRECAUTIONS).
Clinical Studies
The efficacy of CLOBEX® (clobetasol propionate) Lotion, 0.05% in psoriasis
and atopic dermatitis has been demonstrated in two adequate and well-controlled
clinical trials. The first study was conducted in patients with moderate to
severe plaque psoriasis. Patients were treated twice daily for 4 weeks with
either CLOBEX® (clobetasol propionate) Lotion, 0.05% or vehicle lotion.
Study results demonstrated that the efficacy of CLOBEX® Lotion (clobetasol propionate lotion) , 0.05% in
treating moderate to severe plaque psoriasis was superior to that of vehicle.
At the end of treatment (4 weeks), 30 of 82 patients (36.6%) treated with CLOBEX® Lotion (clobetasol propionate lotion) , 0.05% compared with 0 of 29 (0%) treated with vehicle achieved success. Success was defined as a score of none or very mild (no or very slight clinical signs or symptoms of erythema, plaque elevation, or scaling) on the Global Severity scale of psoriasis.
The second study was conducted in patients with moderate to severe atopic dermatitis. Patients were treated twice daily for 2 weeks with either CLOBEX® (clobetasol propionate) Lotion, 0.05% or vehicle lotion. Study results demonstrated that the efficacy of CLOBEX® Lotion (clobetasol propionate lotion) , 0.05% in treating moderate to severe atopic dermatitis was superior to that of vehicle.
At the end of treatment (2 weeks), 41 of 96 patients (42.7%) treated with CLOBEX®
Lotion, 0.05% compared with 4 of 33 (12.1%) treated with vehicle achieved success.
Success was defined as a score of none or very mild (no or very slight clinical
signs or symptoms of erythema, induration/papulation, oozing/crusting, or pruritus)
on the Global Severity scale of atopic dermatitis.
Last reviewed on RxList: 12/1/2008
This monograph has been modified to include the generic and brand name in many instances.