Halobetasol Propionate

Halobetasol Propionate Lotion 0.05% has been shown to suppress the hypothalamic-pituitary-adrenal (HPA) axis.Systemic effects of topical corticosteroids may include reversible HPA axis suppression, with the potential for glucocorticosteroid insufficiency. This may occur during treatment or upon withdrawal of treatment of the topical corticosteroid.The potential for hypothalamic-pituitary adrenal (HPA) suppression with Halobetasol Propionate Lotion 0.05% was evaluated in the following studies:

• In a study of 20 adult subjects with moderate to severe plaque psoriasis involving 􀃙20% of their body surtace area.Halobetasol Propionate Lotion 0.05% produced HPA axis suppression when used twice daily for two weeks in 5 out of 20 (25%) adult subjects with plaque psoriasis. The effects of HPA axis suppression were reversible on discontinuation of the treatment [see Clinical Pharmacology ( 12.2 )].
• In another clinical study, 16 adolescent subjects (12 to less than 17 years old) with moderate to severe plaque psoriasis involving 10% or more of their body surtace area applied a maximum of approximately 50 grams of Halobetasol Propionate Lotion 0.05% to affected areas twice daily for two weeks. Of the 14 subjects evaluated for HPA axis suppression, adrenal suppression occurred in 1 subject (7%) which recovered upon retest [see Clinical Pharmacology ( 12.2 )].

Because of the potential for systemic absorption, use of topical corticosteroids, including Halobetasol Propionate Lotion 0.05%, may require that patients be evaluated periodically for evidence of HPA axis suppression. Factors that predispose a patient using a topical corticosteroid to HPA axis suppression include the use of more potent corticosteroids, use over large surtace areas, prolonged use, occlusive use, use on an altered skin barrier, concomitant use of multiple corticosteroid-containing products, liver failure, and young age. An ACTH stimulation test may be helpful in evaluating patients for HPA axis suppression.

If HPA axis suppression is documented, attempt to gradually withdraw the drug, reduce the frequency of application, or substitute a less potent steroid. Manifestations of adrenal insufficiency may require supplemental systemic corticosteroids. Recovery of HPA axis function is generally prompt and complete upon discontinuation of topical corticosteroids.Systemic effects of topical corticosteroids may also include Cushing's syndrome, hyperglycemia, and glucosuria. Use of more than one corticosteroid-containing product at the same time may increase the total systemic exposure to topical corticosteroids.

Pediatric patients may be more susceptible than adults to systemic toxicity from the use of topical corticosteroids due to their larger surtace-to-body mass ratios [see Use in Specific Populations ( 8.4)].

Local adverse reactions from topical corticosteroids may include atrophy, striae, telangiectasias, burning, itching, irritation, dryness, folliculitis, acneiform eruptions, hypopigmentation, perioral dermatitis, allergic contact dermatitis, secondary infection, and miliaria. These may be more likely to occur with occlusive use, prolonged use, or use of higher potency corticosteroids, including Halobetasol Propionate Lotion 0.05%. Some local adverse reactions may be irreversible.

Use of topical corticosteroids may increase the risk of posterior subcapsular cataracts and glaucoma. Cataracts and glaucoma have been reported in postmarketing experience with the use of topical corticosteroid products.

Advise patients to report any visual symptoms and consider referral to an ophthalmologist for evaluation.

Use an appropriate antimicrobial agent if a skin infection is present or develops. If a favorable response does not occur promptly, discontinue use of Halobetasol Propionate Lotion 0.05% until the infection has been adequately treated.

Allergic contact dermatitis with corticosteroids is usually diagnosed by observing failure to heal rather than noting a clinical exacerbation. Consider confirmation of a clinical diagnosis of allergic contact dermatitis by appropriate patch testing. Discontinue Halobetasol Propionate Lotion 0.05% if allergic contact dermatitis is established.

Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice.

During randomized, controlled, blinded clinical trials 277 adults with plaque psoriasis were treated with Halobetasole Propionate Lotion 0.05% twice daily for up to two weeks (up to approximately 50 grams/week).

Table 1 presents adverse reactions that occured in at least 1% of subjects treated with Halobetasol Propionate Lotion 0,05% twice daily for up to two weeks, and more frequently than in vehicle-treated subjects.

Less common dverse reactions (incidence less than 1% but greater than 0.1%) that occured in subjects treated with Halobetasol Propionate Lotion 0,05% included application site discoloration, herpes zoster, influenza, nasopharyngitis, otitis media acute, throat infection, wound, and increased blood pressure.

-

Safety and effectiveness of Halobetasol Propionate Lotion 0.05% for the treatment of moderate to severe plaque psoriasis have been established in patients 12 years of age and older. It is supported by evidence from adequate and well-controlled trials in adults and from one uncontrolled safety trial in 16 adolescents (12 to less than 17 years of age). Adolescent patients with moderate to severe plaque psoriasis covering a minimum of 10% of the total body surface area were treated twice daily for 2 weeks with Halobetasol Propionate Lotion 0.05%. Hypothalamic-pituitary adrenal (HPA) axis function (ACTH stimulation test) was evaluated in a subset of 14 patients. After 2 weeks of treatment, 1 of 14 patients (7%) experienced laboratory evidence of adrenal suppression (i.e., cortisol serum level of sl 8 μg/dL) that recovered upon retest. No other adverse reactions were reported in the study.

Because of higher skin surtace area to body mass ratios, pediatric patients are at a greater risk than adults of HPA axis suppression and Cushing's syndrome when they are treated with topical corticosteroids. They are therefore also at greater risk of adrenal insufficiency during or after withdrawal of treatment. Adverse reactions including striae have been reported with use of topical corticosteroids in infants and children.

HPA axis suppression, Cushing's syndrome, linear growth retardation, delayed weight gain, and intracranial hypertension have been reported in children receiving topical corticosteroids. Manifestations of adrenal suppression in children include low plasma cortisol levels and an absence of response to ACTH stimulation. Manifestations of intracranial hypertension include bulging fontanelles, headaches, and bilateral papilledema.

Clinical studies with Halobetasol Propionate Lotion 0.05% included 89 subjects aged 65 years and over. No overall differences in safety or effectiveness were observed between these subjects and those younger than 65 years. Clinical studies of Halobetasol Propionate Lotion 0.05% did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently from younger subjects.

Corticosteroids play a role in cellular signaling, immune function, inflammation, and protein regulation; however, the precise mechanism of action in plaque psoriasis is unknown.

The extent of percutaneous absorption of topical corticosteroids is determined by many factors, including the vehicle, the integrity of the epidermal barrier, and the use of occlusive dressings. Topical corticosteroids can be absorbed from normal intact skin. Inflammation and/or other disease processes in the skin may increase percutaneous absorption.

In the HPA clinical study /see Clinical Pharmacology (12.2)1, pharmacokinetics was evaluated in a subgroup of 12 adult subjects. On Day 8, blood was taken just prior to and at 1, 2, 4, 6, 8, and 12 hours following the last application. Plasma concentration of halobetasol propionate (HBP) was measurable in all subjects. Based on the geometric mean plasma concentrations at 12 hours post-application across time, steady-state was achieved by Day 8. The mean (±standard deviation) C _maxconcentrations for Halobetasol Propionate Lotion 0.05% on Day 8 was 201.1 ± 157.5 pg/ml, with the corresponding median T _maxvalue of 3 hours (range O - 6 hours); mean area under the halobetasol propionate concentration versus time curve over the dosing interval (AUCt) was 1632 ± 1147 pg•h/ml.

Specific Populations
Pediatric Patients

In the pediatric HPA study [see Clinical Pharmacology (12.2)], trough plasma concentrations of HBP were measured on Day 8 and Day 15 in a subset of 14 subjects. The HBP levels in the plasma were below the quantification limit (20 pg/ml) for all subjects at all time points with the exception of one subject at Day 15 (trough concentration of HBP of 28.2 pg/ml).

Long-term animal studies have not been performed to evaluate the carcinogenic potential of halobetasol propionate.

In a 90-day repeat-dose toxicity study in rats, topical administration of Halobetasol Propionate Topical Foam at dose concentrations from 0.005% to 0.05% or from 0.011 to 0.11 mg/kg/day of halobetasol propionate resulted in a toxicity profile consistent with long-term exposure to corticosteroids including adrenal atrophy, histopathological changes in several organ systems indicative of severe immune suppression, and opportunistic fungal and bacterial infections. A no observable adverse effect level could not be determined in this study. Although the clinical relevance of the findings in animals to humans is not clear, sustained glucocorticoid-related immune suppression may increase the risk of infection and possibly the risk of carcinogenesis.

Halobetasol propionate was not found to be genotoxic in the Ames/Salmonella assay, in the Chinese hamster CHO/HGPRT assay, in the mouse micronucleus test, in the sister chromatid exchange test in somatic cells of the Chinese hamster, or in the chromosome aberration test in somatic cells of Chinese hamsters. Positive mutagenicity effects were observed in two genotoxicity assays: Chinese hamster nuclear anomaly test and mouse lymphoma gene mutation assay in vitro.

Studies in the rat following oral administration at dose levels up to 0.05 mg/kg/day indicated no impairment of fertility or general reproductive performance.

Halobetasol Propionate Lotion 0.05 % is white to off-white lotion. It is supplied in an oval tapered white high-density polyethylene bottle with a white polypropylene disc cap. Each bottle contains 60 ml (59 g) of Halobetasol Propionate Lotion 0.05%.

NDC 85437-008-60 ml (59 g) bottle

Store at 25'C (77'F); excursions permitted to 15°G and 30°G (59° F to 86°F) [see USP Controlled Room Temperature]. Do not freeze.