Better ways to control AD symptoms on the horizon

Vancouver - Growing understanding of the pathophysiology of atopic dermatitis is instrumental in developing new methods of treatment. Although the condition is still incurable, methods are available that may help better control the symptoms, experts say.

Current strategy

Topical corticosteroids are often the first line of therapy for moderate to severe atopic dermatitis, with the potential for skin atrophy, purpura and systemic side effects. There is also a risk of rebound or tachyphylaxis reaction to the corticosteroids.

Maintenance option Dr. Luger says ultraviolet therapy is a useful maintenance option, making use of UVA/UVB and PUVA light sources. Phototherapy offers good efficacy but patients relapse frequently, and risk the effects of photoaging and potential photocarcinogenicity. He says it's not appropriate for children.

Systemic immunosuppressants are viable therapies for refractory disease. Dr. Lugar lists the drawbacks of three primary choices.

"Cyclosporin A is effective when compared with a placebo, but relapse occurs quickly if therapy is discont-inued. Mycophenolate mofetil (MMF) has shown to be effective in pilot studies but controlled clinical trials are needed. And there are safety concerns with the long term use of systemic corticosteroids."

In addition to the primary treatment options, atopic dermatitis is usually approached with adjunctive therapies, too. Those include: emollients, avoiding trigger factors, antiseptics and oral antibiotics, antiviral therapy, psychological intervention and antihistamines.

Limitations While current therapies may be effective as short-term therapies, they don't offer good long term management. Most are accompanied by significant side effects. Patients don't always tolerate the therapies very well, and they don't cure the diseases. Those are major reasons physicians are looking at newer calcineurin inhibitors such as pimecrolimus, tacrolimus, ascrolimus ABT 281 and ISA TX 247.

Comparing the calcineurin inhibitors to corticosteroids, they appear to avoid some of the more troubling side effects.

Dr. Lugers says, "Protopic (tacrolimus) appears to be a safe and effective treatment for atopic dermatitis in both adults and children over the age of 2. It appears to result in improvement of eczema and pruritus with no signs of skin atrophy or any evidence of tachyphylaxis or rebound. There seems to be minimal systemic exposure with no detectable systemic immunosuppression."

He adds that further clinical trials are required.

Clinical trials have been under way on Elidel Cream 1% (pimecrolimus, ASM 981), manufactured by Novartis. More than 2,000 patients have been enrolled in controlled clinical studies in the past eight years and 6,000 patients are involved in open clinical studies. Post marketing data is available on more than 5 million patients.

Dr. Luger concludes that Elidel is a safe and effective treatment for both adults and children. He says users show significant improvement of eczema and pruritus and show no signs of skin atrophy, no potential for a photocarcinogenic response, no evidence of tachyphylaxis or rebound or adverse systemic events. He adds that the response to vaccination is not impaired.

Dr. Luger says new paradigms for the treatment of atopic dermatitis depend on the intensity of the disease. Going from least severe to severe, they are:

1) Emollients

2) Topical calcineurin inhibitor (TCI) Elidel 1%-Protopic 0.03%, which should start at the first signs or symptoms of disease.

3a) TCI Protopic 0.1% Elidel 1 percent (Plush corticosteroids).

3b) TCI - Protopic 0.1% plus topical corticosteroids.

4) Oral rescue medications such as cyclosporine.