5.1 Hypothalamic-Pituitary-Adrenal (HPA) Axis Suppression and Other Unwanted Systemic Glucocorticoid Effects

PANDEL can produce reversible hypothalamic-pituitary-adrenal (HPA) axis suppression with the potential for glucocorticosteroid insufficiency. This may occur during or after withdrawal of treatment. Factors that predispose to HPA axis suppression include the use of high-potency corticosteroids, large treatment surface areas, prolonged use, use of occlusive dressings, altered skin barrier, liver failure, and young age.

Use of topical corticosteroids may require periodic evaluation for HPA axis suppression. Evaluation for HPA axis suppression may be done by using the adrenocorticotropic hormone (ACTH) stimulation test.

If HPA axis suppression is documented, gradually withdraw the drug, reduce the frequency of application, or substitute with a less potent corticosteroid. If signs and symptoms of steroid withdrawal occur, supplemental systemic corticosteroids may be required. Recovery of HPA axis function is generally prompt and complete upon discontinuation of the drug.

In a trial including 15 evaluable subjects 18 years of age or older with psoriasis or atopic dermatitis affecting more than 20% of body surface area, 1 subject (6.7%) had ACTH stimulation test results suggestive of adrenal suppression after treatment with PANDEL twice daily for 21 days. Recovery of HPA axis suppression for this subject is unknown [see Clinical Pharmacology (12.2)].

Systemic effects of topical corticosteroids may also manifest as Cushing’s syndrome, hyperglycemia, and unmasking latent diabetes mellitus.

Patients applying a topical steroid to a large surface area or to areas under occlusion should be evaluated periodically for evidence of HPA-axis suppression.

Pediatric patients may be more susceptible to systemic toxicity due to their larger skin surface to body mass ratios [see Use in Specific Populations (8.4)].

5.2 Allergic Contact Dermatitis

Allergic contact dermatitis with corticosteroids is usually diagnosed by observing a failure to heal rather than noting a clinical exacerbation, as observed with most topical products not containing corticosteroids. If irritation develops, discontinue PANDEL and institute appropriate therapy.

6.1 Clinical Trials Experience

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 clinical practice.

The most frequent adverse reactions reported for PANDEL during clinical trials were application site reactions, including burning in 4, stinging in 2, and moderate paresthesia in 1 out of 226 subjects.

6.2 Postmarketing Experience

The following adverse reactions have been identified during postapproval use of PANDEL because these reactions were reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.

These adverse reactions are as follows:
Skin and Subcutaneous Tissue Disorders: rash, papulovesicular rash
Application Site Reactions: dryness, erythema, pruritus, allergic contact dermatitis.

The following local adverse reactions are reported with topical corticosteroids, and they may occur more frequently with the use of occlusive dressings. These reactions are listed in an approximate decreasing order of occurrence: itching, irritation, dryness, folliculitis, hypertrichosis, acneiform eruptions, hypopigmentation, perioral dermatitis, allergic contact dermatitis, secondary infections, skin atrophy, striae, and miliaria.

8.1 Pregnancy

Risk Summary
There is no clinical information on PANDEL use in pregnant women to inform any drug-associated risk for major birth defects and miscarriage. In animal reproduction studies, hydrocortisone probutate given by the subcutaneous route during the period of organogenesis was teratogenic at doses equal to or greater than 1 mg/kg/day in rats or 0.1 mg/kg/day in rabbits (12 times and 2 times the human topical dose, respectively) [see Data].

The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively.

Data
Animal Data
Effects on embryo-fetal development were evaluated in rats and rabbits following subcutaneous administration of hydrocortisone probutate during the period of organogenesis. Hydrocortisone probutate was teratogenic in rats when given during the period of organogenesis at subcutaneous doses equal to or greater than 1 mg/kg/day (12 times the human average topical dose of PANDEL assuming 3% absorption and an application of 30 g/day on a 70 kg individual). Abnormalities included delayed ossification of the caudal vertebrae and other skeletal variations, cleft palate, umbilical hernia, edema, and exencephalia.

In rabbits, hydrocortisone probutate given by the subcutaneous route was teratogenic at doses equal to or greater than 0.1 mg/kg/day (2 times the human average topical dose of PANDEL assuming 3% absorption and an application of 30 g/day on a 70 kg individual). Fetal weight and survival were affected. Delayed ossification and increased incidences of malformations (skeletal abnormalities and cleft palate) were also noted.

No adverse effects were seen in rats following subcutaneous administration of up to 1 mg/kg/day of hydrocortisone probutate during the perinatal and postnatal period (12 times the human average topical dose of PANDEL assuming 3% absorption and an application of 30 g/day on a 70 kg individual).

8.2 Lactation

Risk Summary
There is no information on the presence of hydrocortisone probutate in breast milk, or on its effects on the breastfed infant or on milk production. It is not known whether topical administration of PANDEL could result in sufficient systemic absorption to produce detectable quantities in human milk. The developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for PANDEL and any potential adverse effects on the breastfed infant from PANDEL or from the underlying maternal condition.

Clinical Considerations
To minimize potential exposure to the breastfed infant via breast milk, use PANDEL on the smallest area of skin and for the shortest duration possible while breastfeeding.

8.4 Pediatric Use

Safety and effectiveness in pediatric patients have not been established. Because of a higher ratio of skin surface area to body mass, 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 a greater risk of adrenal insufficiency during and/or after withdrawal of treatment. Adverse effects including striae have been reported with inappropriate use of topical corticosteroids in infants and children.

Hypothalamic-pituitary-adrenal (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.

12.1 Mechanism of Action

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

12.2 Pharmacodynamics

Vasoconstrictor Assay
Studies performed with PANDEL indicate that it is in the medium range of potency as demonstrated in vasoconstrictor trials in healthy subjects when compared with other topical corticosteroids. However, similar blanching scores do not necessarily imply therapeutic equivalence.

Hypothalamic-Pituitary-Adrenal (HPA) Axis Suppression
In an open label HPA axis suppression trial, 19 adult subjects (ages 23 to 82 years) with atopic dermatitis or plaque psoriasis covering greater than 20% Body Surface Area (BSA) were treated with PANDEL twice daily for 21 days and were assessed for HPA axis suppression. At baseline, the mean disease BSA involvement was 36%. The criterion for HPA axis suppression was a serum cortisol level of less than or equal to 18 micrograms per deciliter at 30-minutes after cosyntropin stimulation. Of these subjects, 15 were considered evaluable with respect to their adrenal axis function post-treatment. One of the evaluable subjects (6.7%) showed laboratory evidence of suppression on Day 22. This subject had psoriasis covering 48% of BSA at baseline and was reported to have received 98% of the twice-daily applications of PANDEL over the 21 day treatment period. It is not known if this subject had recovery of adrenal function because follow-up testing was not performed.

12.3 Pharmacokinetics

The extent of percutaneous absorption of topical corticosteroids is determined by many factors, including the vehicle and the integrity of the epidermal barrier. Use of occlusive dressings with hydrocortisone for up to 24 hours has not been shown to increase penetration; however, occlusion of hydrocortisone for 96 hours does markedly enhance penetration. Topical corticosteroids can be absorbed from normal intact skin. Inflammation and/or other disease processes in the skin increase percutaneous absorption.

13.1 Carcinogenesis, Mutagenesis, Impairment of Fertility

No long-term studies in animals have been performed to evaluate the carcinogenic potential of hydrocortisone probutate.

Hydrocortisone probutate revealed no evidence of mutagenic or clastogenic potential based on the results of an in vitro genotoxicity test (Ames assay) and an in vivo genotoxicity test (mouse micronucleus assay).

Effects on fertility and early embryonic development were evaluated in rats following subcutaneous administration of up to 0.4 mg/kg/day hydrocortisone probutate (5 times the human average topical dose of PANDEL assuming 3% absorption and an application of 30 g/day on a 70 kg individual) prior to and during mating and through early pregnancy. No treatment related effects on fertility or mating parameters were noted in this study.