Safety and efficacy of topical calcineurin inhibitors in the treatment of childhood atopic dermatitis

Comparative Effect of Tacrolimus and Betamethasone Valerate on the Passive Sustainable Hydration of the Stratum Corneum in Atopic Dermatitis

BACKGROUND

There is ample evidence that the skin barrier function is altered in atopic dermatitis. Little information is available about the effect of topical corticosteroids and calcineurin inhibitors on this function.

PURPOSE

To assess the water content and its rate of accumulation in the stratum corneum of atopic patients using an indirect electrometric method while on tacrolimus or betamethasone valerate treatment.

METHOD

Twenty-one patients with moderate atopic dermatitis affecting both forearms completed this double-blind randomized study. One forearm was treated twice daily for 3 weeks with 0.1% tacrolimus ointment. The other forearm was similarly treated with 0.12% betamethasone valerate ointment. Electrometric measurements were made under continuous occlusion secured by a Nova Dermal Phase Meter sensor probe. Assessments were performed at inclusion, after the 3-week treatment and after a further 3-week follow-up out of treatment.

RESULTS

During treatment, both compounds yielded a similar improvement in skin barrier function. Indeed, under probe occlusion, the rate of water accumulation was significantly decreased. This improvement was sustained after stopping the tacrolimus treatment. By contrast, the benefit was in part lost at the site that had been treated by betamethasone valerate.

CONCLUSION

The difference in the effect of the 2 compounds may be due to the negative influence of betamethasone valerate on the epidermal metabolism leading to progressive atrophy of the tissue. The better preservation of the skin barrier function after stopping tacrolimus treatment may help retarding relapses of atopic dermatitis.

Blood concentrations of pimecrolimus in adult patients with atopic dermatitis following intermittent administration of pimecrolimus cream 1% (Elidel) for up to 1 year

OBJECTIVES

To determine blood concentrations of pimecrolimus after long-term intermittent administration of pimecrolimus cream 1% in adult patients with extensive atopic dermatitis (AD).

METHODS

This was an open-label, multiple topical dose study in adults with moderate to severe AD and a total body surface area (TBSA) involvement of at least 20%. Pimecrolimus cream 1% was administered twice daily according to treatment need for up to 12 months to all lesions, including the neck and face. Blood samples were collected at regular time points and pimecrolimus concentrations were measured using a radioimmunoassay with a limit of quantitation (LoQ) of 0.5 ng/ml.

RESULTS

Forty patients (19 females), aged from 19 to 59 years, with moderate to severe AD entered the study. Twenty patients completed 6 months and 13 completed 1 year in the study. The individual blood concentrations of pimecrolimus were consistently low and there was no sign of drug accumulation. In 900 of the 918 samples examined (98%), pimecrolimus concentrations remained below the LoQ. The maximum concentration observed throughout the entire study was 0.8 ng/ml.

CONCLUSION

Long-term intermittent treatment of adult patients with extensive AD with pimecrolimus cream 1% is associated with minimal systemic exposure and no evidence of drug accumulation.

Review of pimecrolimus cream 1% for the treatment of mild to moderate atopic dermatitis

BACKGROUND

Atopic dermatitis (AD) is a pruritic and inflammatory skin disease affecting at least 28 million people in the United States. During an AD flare, the skin becomes inflamed and intensely pruritic. A "major flare" is characterized by persistent or uncontrollable pruritus, intense erythema, extensive excoriation, and potential oozing and crusting. The overall goal of AD treatment is to minimize the frequency and severity of disease flares. Long-term management involves multiple treatment strategies, including identifying and eliminating triggers, routine moisturization, antipruritic therapy, and use of topical anti-inflammatory agents (topical corticosteroids and topical calcineurin inhibitors). Pimecrolimus cream 1% is a topical calcineurin inhibitor developed specifically for patients with AD.

OBJECTIVE

The aim of this review was to assess the current literature (clinical trials and postapproval studies) on the efficacy and safety of pimecrolimus cream 1% in the treatment of AD.

METHODS

A literature search was performed using the National Library of Medicine (MEDLINE), EMBASE, International Pharmaceutical Abstracts, Current Contents, and SciSearch databases (1980-2006) with the search term pimecrolimus. Selected studies comprised randomized, vehicle-controlled trials of topical pimecrolimus cream 1%, focused on efficacy and safety, and complied with the pimecrolimus cream 1% indication (study participants were aged >or=2 years with mild to moderate AD).

RESULTS

When used in appropriately identified pediatric and adult patients with mild to moderate AD, pimecrolimus cream 1% improved the signs and symptoms of AD and delayed time to a major flare. The most commonly seen adverse events in clinical trials were application-site reactions (10.4%-14.5%) and nasopharyngitis (10.1%-28.9%), headache (13.9%-23.0%), cough (11.6%-19.3%), pyrexia (7.5%-15.4%), influenza (3.0%-14.6%), and bronchitis (0.4%-13.2%), which overall were not significantly different from patients treated with vehicle cream. Pimecrolimus cream 1% was not associated with skin atrophy (supporting its use on sensitive areas of the skin such as the face, neck, and skinfolds). In addition, a review of the literature identified no reports of cumulative irritation or photosensitivity potential, no substantial increases in the incidence of common bacterial and viral skin infections compared with vehicle cream (placebo), and no effects on the systemic immune system, including delayed-type hypersensitivity.

CONCLUSION

Pimecrolimus cream 1% is a valuable treatment option for mild to moderate AD in adults and children aged >or=2 years.

Diagnosis and treatment of atopic dermatitis in children and adults: European Academy of Allergology and Clinical Immunology/American Academy of Allergy, Asthma and Immunology/PRACTALL Consensus Report

There are remarkable differences in the diagnostic and therapeutic management of atopic dermatitis practiced by dermatologists and pediatricians in different countries. Therefore, the European Academy of Allergy and Clinical Immunology and the American Academy of Allergy, Asthma and Immunology nominated expert teams who were given the task of finding a consensus to serve as a guideline for clinical practice in Europe as well as in North America. The consensus report is part of the PRACTALL initiative, which is endorsed by both academies.

Immunomodulation and safety of topical calcineurin inhibitors for the treatment of atopic dermatitis

Atopic dermatitis (AD) is a chronic or chronically relapsing inflammatory skin condition that primarily affects children. Topical corticosteroids have been the mainstay of treatment since the late 1950s. While providing excellent short-term efficacy, topical corticosteroid usage is limited by potential adverse effects, including impairment of the function and viability of Langerhans cells/dendritic cells. The recently introduced topical calcineurin inhibitors pimecrolimus cream 1% (Elidel) and tacrolimus ointment 0.03 and 0.1% (Protopic) exhibit a more selective mechanism of action and do not affect Langerhans cells/dendritic cells. For the immune system of young children 'learning' to mount a balanced Th1/Th2 response, this selective effect has particular benefits. In clinical experience, topical calcineurin inhibitors have been shown to be a safe and effective alternative to topical corticosteroids in almost 7 million patients (>5 million on pimecrolimus; >1.7 million on tacrolimus). Topical pimecrolimus is primarily used in children with mild and moderate AD, whereas tacrolimus is used preferentially in more severe cases. None of the topical calcineurin inhibitors have been associated with systemic immunosuppression-related malignancies known to occur following long-term sustained systemic immunosuppression with oral immunosuppressants (e.g., tacrolimus, cyclosporine A, and corticosteroids) in transplant patients. Preclinical and clinical data suggest a greater skin selectivity and larger safety margin for topical pimecrolimus.

Pimecrolimus 1% cream for the treatment of discoid lupus erythematosus

OBJECTIVES

To determine the safety and efficacy of pimecrolimus cream on lesions of discoid lupus erythematosus.

METHODS

In an open-label phase II trial, patients with discoid lupus were treated with pimecrolimus 1% cream twice daily for 8 weeks. We assessed skin involvement with a clinical severity score, quality of life, patient improvement and toxicity. The changes were documented by skin biopsy at baseline and at the end of treatment.

RESULTS

Ten patients with a mean age of 34 +/- 17 yr and disease duration of 3 yr (range 1-8) were studied; 90% were female and 40% had received prior topical or systemic therapy without response. In all patients, improvement of skin damage was observed after therapy. A significant decrease of 52% was observed in the mean +/- s.d. clinical severity score, from 6.1 +/- 1.4 before treatment to 2.9 +/- 1.5 after treatment (P = 0.005). Quality of life score (0 = no effect, 100 = maximum effect on quality of life) showed a mean improvement of 46%, from 42.8 +/- 23.1 before to 23 +/- 16.5 after treatment (P = 0.008). According to the patients' assessment of the response to treatment, 50% qualified as marked improvement, 40% moderate and 10% slight improvement. The treatment was well tolerated; adverse reactions consisted of minimal erythema and pruritus, which resolved without any further action.

CONCLUSIONS

Our data suggest that pimecrolimus cream for discoid lupus erythematosus seems to be a safe and clinically effective option. However, this was an open and uncontrolled study, and double-blind, placebo-controlled studies are needed.