Getting the red out: drug improves kids' psoriasis symptoms

Science News, Jan 19, 2008 by Nathan Seppa

A rheumatoid arthritis drug can clear up psoriasis in most children, a new study finds. The report might be enough to cinch regulatory approval for the drug, etanercept, as the first systemic medication for psoriasis in youngsters.

Psoriasis results from runaway inflammation that promotes excess skin-cell growth, creating thick red patches all over the body. Currently approved treatments such as skin creams and ultraviolet light often provide only limited help for children with psoriasis.

To test etanercept, an anti-inflammatory drug previously approved for treating psoriasis in adults, researchers enlisted 211 children ages 4 to 17 who had moderate to severe disease. On average, the children had patches covering one-fifth of their bodies.

The children received a weekly injection of either the drug or a placebo for 12 weeks. At that point, 53 percent of those receiving etanercept had "clear or almost clear" skin, according to doctors treating them, compared with only 13 percent of those getting placebo shots. More precise measurements found that the area of affected skin fell by at least 50 percent in three quarters of the children getting etanercept, says study coauthor Amy Paller, a dermatologist at Northwestern University Medical School in Chicago.

After 12 weeks, everyone in the study was offered the drug. "Pretty much all of them improved," says Craig Leonardi, a dermatologist at Saint Louis University. He was one of dozens of U.S. and Canadian doctors who treated and monitored children as part of the study. The results appear in the Jan. 17 New England Journal of Medicine.

"This is an important step in bringing a new therapy to bear in a patient population that was underserved," Leonardi says.

Etanercept blocks the inflammation underlying psoriasis by targeting a key inflammatory protein called TNF-alpha, says Siba Raychaudhuri, a dermatologist at the University of California, Davis. Studies in the 1990s led the Food and Drug Administration to approve etanercept for adults and children with rheumatoid arthritis, an inflammatory disease.

Amgen, the Thousand Oaks, Calif.-based company that markets etanercept as Enbrel, has now asked the FDA to designate the drug for pediatric psoriasis. A decision is expected later this year.

Approval would provide clinicians with an alternative to other immune suppressants such as methotrexate and cyclosporine. Doctors prescribe these drugs for children with difficult-to-treat psoriasis, Paller says, even though they aren't specifically approved for this group.

However, use of such heavy immune suppressants leaves a person vulnerable to infection. That's a prime concern for children, who battle ear infections and respiratory ailments regularly, Leonardi says.

Etanercept's specific targeting of TNF-alpha allows other immune processes to continue to protect the body, says rheumatologist Ellen McCroskery of Amgen. "We think that's a very good thing."