Emerging therapies could ease symptoms of Atopic dermatitis

Mar 5 2009

Atopic dermatitis, the common, chronic, inflammatory skin disease marked by red, itchy rashes, has been increasing in prevalence over the past two decades and affects a disproportionate number of children.

According to current estimates, approximately 15 percent to 20 percent of children in the United States and other industrialized countries around the world develop atopic dermatitis in the first few years of life. By comparison, only an estimated 3 percent to 5 percent of adults have an active form of the condition.* Now, a promising new array of therapies targeting different aspects of atopic dermatitis stands to help patients find relief from the physical and emotional pain caused by this complex condition.

Speaking at the 67th Annual Meeting of the American Academy of Dermatology (Academy), dermatologist Lawrence F. Eichenfield, MD, FAAD, professor of pediatrics and medicine (dermatology) at the University of California, San Diego, School of Medicine, reviewed the latest therapies for atopic dermatitis and how the new understanding of the cause of the condition has led to an improved and more targeted treatment approach.

"There has been an abundance of new research looking at genetic abnormalities associated with atopic dermatitis, including those in the skin's barrier function - or its protective outer layer," said Dr. Eichenfield. "It appears that a subset of patients with atopic dermatitis and eczema is born with problems with the function of their outer layer of skin, which can cause the skin to be drier and more prone to the absorption of irritants, microbes and allergens that can penetrate the skin and cause adverse reactions. Fortunately, this new understanding is leading to new and better treatments for patients of all ages."

Topical Corticosteroids

Used to diminish the skin's inflammatory response, topical corticosteroids are a mainstay in the treatment of atopic dermatitis. Now, newer formulations of topical corticosteroids in gels, foams and oils, which have undergone specific safety and efficacy testing, have been approved for use in younger patients - including infants as young as three months of age. The products that are approved by the U.S. Food and Drug Administration (FDA) for this age group to treat atopic dermatitis and eczema include fluocinolone acetonide, topical oil 0.01%, desonide gel 0.05% and desonide foam 0.05%.

Dr. Eichenfield noted that some patients have expressed concern about the cost of treatments. Since major pharmacy retailers are promoting generic drug programs, patients may find a more cost-effective therapy for managing chronic atopic dermatitis.

"The newer approved formulations may cost more compared to the generic medications, so it is important for patients to discuss generic options with their dermatologist," said Dr. Eichenfield.

Topical Calcineurin Inhibitors

Another category of atopic dermatitis therapies used to suppress inflammation of the skin is topical calcineurin inhibitors, which includes the FDA-approved tacrolimus ointment and pimecrolimus cream. Recently, several new studies have examined whether the intermittent use of topical calcineurin inhibitors can effectively control atopic dermatitis. In patients whose atopic dermatitis was initially controlled with the application of topical corticosteroids or tacrolimus ointment, applying topical calcineurin inhibitors intermittently was effective in maintaining control of flare-ups.

"Studies have shown that topical calcineurin inhibitors can be very helpful in a variety of atopic dermatitis treatment regimens," said Dr. Eichenfield. "For instance, these recent studies demonstrate that applying topical tacrolimus ointment two to three times per week successfully controlled the condition for months, on average, before a significant flare of dermatitis. Other studies show that using tacrolimus ointment or pimecrolimus cream intermittently at the first signs and symptoms of a flare-up was quite successful. These products may be especially useful for patients who otherwise would have more persistent or frequent recurring eczema."

Barrier Creams and Engineered Emollients

Barrier creams and engineered emollients are newer FDA-approved topical agents that are designed to improve the barrier function of the skin that is compromised in atopic dermatitis. They work by adding lipids, ceramides (natural lipids that act as water regulators) or other agents that help to make damaged skin more "normal." These topical preparations include water-based emulsion with N-palmitoylethanolamide; MAS063ADP, with glycyrrhetinic acid; and ceramide-dominant products.

"Barrier creams and engineered emollients appear very helpful in decreasing symptoms and the need for stronger prescription products, but these medications are fairly new and dermatologists are in the process of assessing their optimal use in atopic dermatitis treatment regimens," said Dr. Eichenfield. "Initial assessments demonstrate that the damaged skin can be improved showing less dryness due to less water loss, less inflammation and less need for more potent anti-inflammatory agents."

Systemic Therapies

For a significant subset of atopic dermatitis patients of all ages, systemic therapy is necessary to control their condition. While systemic therapies for atopic dermatitis pose safety concerns due to their potential side effects, Dr. Eichenfield reported that a few of the newer immunosuppressive agents and newer biologic therapies are being used successfully - even in children.

"Newer immunosuppressives such as mycophenolate mofetil can be very useful in providing relief for patients with more severe cases of atopic dermatitis and have been studied for use in the pediatric population," said Dr. Eichenfield. "In addition, dosing of azathioprine is now based on an individual's genetics and metabolic activity to process the medication, allowing it to be used with less chance of dangerous side effects. Newer studies of the latest biologic therapies, such as efalizumab, show some benefits, but in general more research needs to be done to confirm the safety profile of all systemic therapies for this condition."

Dr. Eichenfield added that given the new understanding of how atopic dermatitis develops in relation to barrier dysfunction, there is an interest in studying whether early intervention with a variety of topical therapies may impact the overall course and severity of atopic dermatitis and prevent or delay the development of other related allergies - such as food allergies and asthma that affect many patients with atopic dermatitis.

"Atopic dermatitis is a chronic disease that significantly impacts individuals and their families," said Dr. Eichenfield. "Patients should consult with their dermatologist to determine whether any of the newer medications or generic medications can successfully manage their condition safely and effectively."

For more information on atopic dermatitis, go to the EczemaNet section of www.skincarephysicians.com, a Web site developed by dermatologists that provides patients with up-to-date information on the treatment and management of disorders of the skin, hair and nails.

Headquartered in Schaumburg, Ill., the American Academy of Dermatology (Academy), founded in 1938, is the largest, most influential, and most representative of all dermatologic associations. With a membership of more than 15,000 physicians worldwide, the Academy is committed to: advancing the diagnosis and medical, surgical and cosmetic treatment of the skin, hair and nails; advocating high standards in clinical practice, education, and research in dermatology; and supporting and enhancing patient care for a lifetime of healthier skin, hair and nails. For more information, contact the Academy at 1-888-462-DERM (3376) or www.aad.org.

Editor's Note: The statistics on prevalence of atopic dermatitis are from "Management of atopic dermatitis in the pediatric population," which was published in Pediatrics in October 2008.