Breakthrough Drug for Psoriasis Sufferers

Part of new class of treatments that could revolutionize medicine

SATURDAY, March 15, 2003 (HealthDayNews) -- Amevive, a revolutionary drug that has just won federal approval, offers new hope to nearly 2 million Americans who suffer from severe psoriasis -- an autoimmune disease that attacks the skin.

Equally important, Amevive is the first of what will ultimately be four new psoriasis treatment options, experts says. All of them fall into a relatively new category of drugs known as "biologics." They may alter the treatment of this disease and other conditions, although biologics aren't without certain risks.

"We're really just seeing a crack in the door of a whole new set of drugs for a variety of things. With Amevive, we're really seeing a glimpse into the future," says Dr. Darrell Rigel, a professor of dermatology at New York University Medical Center.

Biologics are primarily derived from living cells. Unlike traditional medications -- which are usually a compilation of chemicals -- biologics are, by and large, comprised of human or animal proteins. They work to help the body help itself, reinforcing healthy inter-cell communication and intervening when that communication goes awry, as it does in all autoimmune diseases.

"What makes this drug so special is that it is the first treatment to target the specific cells involved in psoriasis. It actually addresses the problem at the root and treats the disease, not just the symptoms," says Dr. Mark Lebwohl, chairman of dermatology at the Mount Sinai School of Medicine in New York City.

With psoriasis, that means targeting the overproduction of skin cells that's the hallmark of the disease. Under normal circumstances, skin cells die and are replaced by new ones in a continuously renewing 30-day cycle. Psoriasis, however, triggers an overreaction by the immune system to an antigen -- or foreign invader -- that causes cellular communications to jam, forcing the skin cell production switch to remain stuck in the "on" position.

As a result, the body continues to turn out batches of new skin cells every three or four days, at 10 times the normal rate. That cell overload eventually builds up on the surface of the skin, resulting in the characteristic red, raised, scaly patches that can make psoriasis a painful -- as well as disfiguring -- disease.

Amevive (alefacept) not only prevents the overstimulation of skin cell production, it attacks and destroys the defective immune cells that started the problem, Lebwohl says.

"It's like a key that fits into the lock that turns off the whole destructive process," he says.

Until recently, the most common treatments for moderate to severe psoriasis were limited, and choosing one was a little like deciding whether you wanted to sit in the flame or the fire.

"One choice is methotrexate, a potentially deadly chemotherapy drug which, while killing the bad cells, also wipes out the bone marrow, and with long term use scars the liver," Lebwohl says.

Another is the drug cyclosporin, which with long-term use damages the kidneys, Lebwohl says.

A third alternative is light therapy, with or without additional medications. While treatments are effective, they must be given frequently and over a long period of time, and that has been associated with skin cancer, experts say.

Also, the relief provided by methotrexate and cyclosporin is limited -- as soon as treatment is stopped, symptoms return, Lebwohl says.

With Amevive, however, the short course of treatment, lasting 12 weeks, yielded relief that lasted seven months or longer. For the longer treatment program -- 24 weeks -- relief lasted more than a year, and may continue indefinitely, clinical trials indicate.

But Amevive has its drawbacks.

One is the cost, which could run as high as $20,000 a year. As it stands now, weekly injections are likely to cost about $1,000 each, with up to 24 weekly treatments needed for the best results. By comparison, methotrexate and light therapy will only set you back about $2,000 for a year of treatments, while cyclosporin costs around $9,000 annually.

In addition, because Amevive temporarily dampens the immune system, it can increase the risk of infection or even malignancy during the course of treatment. So patients are required to undergo regular blood tests, driving treatment costs up even higher. It also means that, depending on individual risk factors for disease, the drug might not be right for every person.

Still, even with these precautions, Rigel says the future is bright for Amevive and the other three biologics expected to hit the market soon for psoriasis sufferers.

"I think that in time the cost will come down," he says. "Plus, I believe this technology will continue to go forward, bringing us new and exciting treatments for many types of illnesses."

"We are on the cutting edge, watching a new era in medicine unfold," Rigel says.

More information

To learn more about treatment with Amevive, visit The National Psoriasis Foundation. For additional information on other treatments for psoriasis, visit The National Library of Medicine.

Related Stories

No stories found.
logo
www.healthday.com