By Will Boggs, MD

NEW YORK (Reuters Health) - Alefacept, a drug that reduces the activity of certain immune cells, is effective in treating psoriasis of the scalp, according to a report in the Journal of the American Academy of Dermatology.

Psoriasis is a chronic skin condition appearing as red patches covered with white scales. The patches are often itchy and may affect large areas of the body, usually in the scalp or extremities. Most researchers believe that psoriasis is an autoimmune disorder, meaning that the damage is caused by the body's own immune system.

"Alefacept works as well in scalp psoriasis as it does in generalized body psoriasis," Dr. James Krell from Total Skin and Beauty Dermatology Center, Birmingham, Alabama, told Reuters Health. Alefacept is also known by the trade name Amevive.

Krell and colleagues evaluated the safety and effectiveness of alefacept in treating scalp psoriasis in 30 adults, all of whom received weekly injections for 16 weeks and then no treatment for 12 weeks. Any patient whose psoriasis did not clear up underwent a second course of treatment.

Five patients were successfully treated with a single course of treatment and five more achieved success with a second course.

After one or two courses of treatment, 16 patients had experienced at least a 75 percent improvement in a test that gauges both the size and severity of psoriasis. Moreover, 14 patients rated themselves as much improved after one or two courses of treatment.

Only one patient reported side effects, such as nausea and general malaise, which occurred when alefacept was started. None of the patients withdrew from the study or missed doses because of low immune cell levels.

"It is always worth keeping alefacept in mind for the right patient when a very safe...medication is needed," Krell concluded.

SOURCE: Journal of the American Academy of Dermatology, April 2008.