June 8, 2001 - Novelist John Updike describes having psoriasis as "being at war with my skin." But the author may soon have a new weapon against the disease: A study published in the June 9 issue of The Lancet suggests that a drug called Remicade -- which is effective against rheumatoid arthritis and inflammatory bowel disease -- is also good at clearing psoriasis lesions.
It's estimated that 1-3% of the population in the U.S. and Europe has psoriasis, a disabling and psychologically demoralizing skin disease caused by an alteration of normal skin growth and wound-repair mechanisms. In the most common form, called plaque psoriasis, patches of skin become thick and red and are covered with silvery scales. The plaques may itch, burn, crack, and bleed, and some patients go on to develop a painful form of arthritis. It is estimated that about one-fourth of patients have moderate to severe forms of the disease.
Although the precise cause of psoriasis is unknown, it is widely considered to be the result of a malfunction in the immune system. Treatment for more serious cases may include the use of immune-system suppressing drugs, such as cyclosporine (which is also used in organ transplants), and methotrexate, a drug that is used in some forms of chemotherapy for cancer. But these drugs can be toxic if taken over the long term, and the disease will flare up again after therapy is stopped.
"We have no cures for psoriasis, so at some point the psoriasis comes back," says Alice B. Gottlieb, MD, PhD, director of the clinical research center at the UMDNJ-Robert Wood Johnson Medical School in New Brunswick, N.J., in an interview with WebMD.
Gottlieb and colleagues conducted a study in which 33 patients with moderate to severe psoriasis covering at least 5% of their bodies were assigned to receive either the intravenous drug Remicade in one of two dosing schedules, or a placebo consisting of sterile water.
Nine of 11 patients who received the drug in doses of 5 mg per kg of body weight had responses judged to be either good, excellent, or complete (complete clearing of lesions), compared with just two of the 11 patients in the placebo group. Eight of 11 patients who received a 10 mg/kg dose of the drug also had at least a 75% improvement in psoriasis severity. The average time for treatment response was about one month in all groups.
No serious side effects were reported from use of the drug, which appeared to be well tolerated, the authors report.
Remicade is targeted against a chemical messenger called tumor necrosis factor alpha, or TNF-a, believed to be involved in the over-proliferation of skin cells that occurs in psoriasis. This medication has been shown to be effective against rheumatoid arthritis and the inflammatory bowel condition Crohn's disease, which has been linked genetically to psoriasis.
"It's not a completely safe treatment, but it's relatively safe," says Marcus Clark, MD, associate professor and chief of rheumatology at the University of Chicago, who commented on the drug for WebMD. "But the cost is high, so I don't know if it will ever be a primary therapy for psoriasis." He adds that as with any immune therapy, there is likely to be a rapid flare-up of the disease when the drug is stopped.
Gottlieb tells WebMD that although the study is ongoing, the remissions appear to be long-lasting in the small group of patients followed for six months or more.
"If this is all borne out by [further] studies, then you'll have a drug that clears as well and as quickly and in as high a proportion of patients as cyclosporine without the rapid relapse," she says. "If cyclosporine were safe to use long-term there would be no more drug development in psoriasis -- it's terrific at clearing psoriasis -- the problem is that it's toxic for long-term use, and when we stopped it all of our patients relapsed within a month. We're not apparently seeing this with Remicade."
Gottlieb is currently a consultant to Centocor, the manufacturer of Remicade.