Canadian Dermatology Association
Amevive: A New Biologics Drug To Treat PsoriasisBy Dr. Gifford Jones
It’s been a long time coming. But finally there’s a new revolutionary treatment to ease the suffering of those afflicted with psoriasis. This infuriating skin disease plagues one million Canadians and treatment has never been easy. But recently at the annual meeting of the Canadian Dermatology Association, doctors reported that a new drug, Amevive, would help subdue this physically and emotionally taxing disease.
What causes psoriasis has been debated for years. In normal skin it takes 30 days for the deepest layer of skin cells to reach the surface where they are eventually cast off. But for patients with psoriasis these cells reach the surface in a mere seven days.
This accelerated growth results in the typical raised, thickened, circular, red plaques covered by fine-silvery scales. They vary in size and number and can cover large areas of the skin. But the big question has always been what triggers this accelerated growth.
Dr. Kim Papp, Dermatologist, Probity Medical Research in Waterloo, Ontario, says researchers now agree that psoriasis is a disease in which the immune system plays a major role. T cells, which normally protect the body from disease, go on a rampage and attack the skin and other organs. It’s as if an army suddenly decided to stop fighting the enemy and instead decided to turn their guns on themselves.
In the past, treatment centered around a variety of skin medications such as coal tar along with ultraviolet light which generally required hospitalization. It was a messy, tedious affair often with questionable results, leaving patients discouraged and dejected.
A study by the National Psoriasis Foundation showed that 79 percent of patients with severe psoriasis were frustrated by the ineffectiveness of their treatments and 32 percent believed that their treatments were not sufficiently aggressive.
Amevive is part of a new class of treatments called “biologics”. It provides doctors with a new unique weapon to fight psoriasis. It’s a smart bomb that works by blocking and eliminating certain T cells responsible for psoriasis. In effect, Amevive stops the confused T-cells from shooting psoriasis-laced bullets at the skin.
Amevive treatment consists of 12 weekly injections which are given via a simple intramuscular route. This is followed by a treatment-free period of 12 weeks. After a second course patients are eligible for more courses of treatment depending on how well they’ve responded to the treatment.
Dr. Wayne Carey, Associate Professor of Dermatology, McGill University, Montreal, says “One of the nice things with this drug is that if patients stop taking Amevive the disease comes back very slowly.”
Dr Yves Poulin, Clinical Professor of Medicine Laval University, Quebec, says it’s the dual action of Amevive that makes this drug so appealing. Amevive not only decreases psoriasis lesions during treatment, but also causes a remission long after the drug has been stopped.
He adds that there is great advantage to giving a second course of Amevive as in one study the average length of remission was over 12 months
Dr Robert Bissonnette, Assistant Professor of Dermatology , Universite de Montreal says “Amevive is usually very well tolerated. About 6 percent of patients report chills after injection but these tend to be mild.” Transient skin reactions such as swelling and redness also occur in about 5 percent of cases.
Patients who take Amevive are required to have their T-cell blood counts checked every other week. Amevive has the potential to increase the risk of infections although an increase in infection was not seen in clinical studies. But studies also suggest it does not affect a person’s normal immune system to fight disease.
Amevive is used only for moderate and severe cases of psoriasis and it does not cure this disease. But studies show it’s effective in over 70 percent of patients with psoriasis.
Today 35 to 45 percent of patients with psoriasis do not seek treatment due to the poor results and side-effects of drugs that take a shot-gun approach to treating this disease.
Amevive, which takes a selective rifle shot at T cells, has a significant advantage over older therapies and provides patients with new hope.