New Psoriasis Treatments Work

Nov. 19, 2003 -- Not so long ago, psoriasis sufferers had few options. Now three already-available drugs offer relief from the agonizing skin disease.

The new drugs are Enbrel, Raptiva, and Amevive. All are "biological" drugs -- they use recent scientific breakthroughs to target specific body functions.

Psoriasis is an autoimmune disease; the new drugs block harmful immune responses. Amevive and Raptiva were approved earlier this year as psoriasis treatments. Enbrel was approved in 1998 to treat rheumatoid arthritis. Enbrel's manufacturer, Wyeth, a WebMD sponsor, has filed for formal approval as a psoriasis treatment.

Separate clinical studies of psoriasis patients treated with Enbrel and Raptiva appear in the Nov. 20 issue of The New England Journal of Medicine. So does an editorial by Thomas S. Kupper, MD, of Brigham and Women's Hospital in Boston.

"At this point, there are insufficient data to support claims that one of these agents is superior to another," Kupper writes. "There may be groups of people who have a better response to one or the other of these agents."

All of these drugs likely must be taken for long periods of time -- perhaps for life. Because they interfere with the immune system, there is a danger that they will raise patients' risk of infections and maybe even cancer. It's not clear how the drugs will work over years and years of treatment. But in the short term, all have remarkable safety records. That's particularly true for Enbrel, which has been used in more than 150,000 patients -- including long-term safety studies in 2,000 patients.

Enbrel: From Arthritis to Psoriasis

Enbrel is a man-made protein that blocks a chemical messenger called TNF (tumor necrosis factor). Blocking TNF quiets the abnormal immune responses seen in arthritis -- and in psoriasis.

Craig L. Leonardi, MD, of St. Louis University, and colleagues tested three different doses of Enbrel in 652 adult patients with moderate-to-severe psoriasis. After 24 weeks of treatment:

• 59% of high-dose patients (50 mg injections twice a week) had at least 75% improvement -- 55% reported "clear" or "almost clear" status.
• 44% of medium-dose patients (25 mg injections twice a week) had at least 75% improvement -- 39% reported "clear" or "almost clear" status.
• 25% of low-dose patients (25 mg injections once a week) had at least 75% improvement -- 26% reported "clear" or "almost clear" status.

"Rapid clearing of skin lesions is an important aspect of effective psoriasis management and may correlate with the patient's satisfaction with treatment," Leonardi and colleagues write. "After two weeks of treatment, [Enbrel] produced statistically significant and clinically meaningful improvements in patients' global assessments of disease and in the quality of life."

Raptiva: Targeting T Cells

Raptiva is a man-made antibody. It goes against T cells, the quarterbacks of the immune system. It doesn't kill the T cells -- instead, it blocks T cells from moving from the blood into the skin.