Injections of an antibody called secukinumab may significantly improve skin lesions in patients with psoriasis, an inflammatory skin disease, according to new research published in The New England Journal of Medicine.
The antibody blocks a key protein believed to cause psoriasis, said lead researcher Dr. Richard Langley, a professor of medicine at Dalhousie Medical School in Halifax.
In two separate trials, about 80 per cent of patients who received the new medication had a 75-per-cent reduction in the severity of their disease, based on a standard clinical scale. A quarter had no sign of the disease after 12 weeks of treatment – "not a spot of psoriasis on them," Langley said.
The trials, funded by the drug company Novartis, involved more than 2,000 patients with moderate to severe psoriasis at 200 research sites worldwide.
Dermatologists with no connection to the study said the findings are good news for psoriasis patients.
The experimental medication "has set a new standard of efficacy," said Dr. Abby S. Van Voorhees, associate professor of dermatology at the University of Pennsylvania and chair of the U.S. National Psoriasis Foundation Medical Board.
Although the study is ongoing, Langley said it is likely that patients will need monthly injections of the antibody over the long term to control their symptoms. "We're not curing the disease," he said. "We're simply halting its progression in some cases."
Psoriasis is an autoimmune disease that causes red, scaly patches to appear on the skin. Historically, psoriasis was confused with leprosy, a curable bacterial infection. Psoriasis is not contagious, but people with the disease – an estimated one million Canadians – may feel debilitated by the itchy and painful skin lesions, and the stigma attached.
Although their faces may look normal, people with psoriasis may avoid playing sports that require showing parts of their bodies, or entering relationships because "they don't want to take their clothes off," Langley said.
Patients with psoriasis have high rates of depression, and an increased risk for heart attacks, inflammatory bowel disease, Type-2 diabetes, hypertension and stroke.
The disease "has a profound negative impact on people's quality of life," Langley said.
Kalab Groulx, 28, knows what it's like to live with severe psoriasis. The first patches appeared on his head and ears when he was 16. Today, more than 90 per cent of his body is covered in tender, itchy scales.
Groulx said he tries not to let the disease interfere with his life, but sometimes when he sees his inflamed skin in the mirror, "I do start to cry."
Groulx has tried psoriasis treatments including UV light therapy and topical creams, and has been on methotrexate, a chemotherapy drug used to treat psoriasis, for several years. "But it's not really working," he said.
Over the past year, his disease has progressed from a skin condition to psoriatic arthritis, which affects the joints. Groulx said he worked at a retail clothing store in Toronto until a month ago, but had to quit because the pain in his ankles, knees, shoulders and spine got too bad. "Right now, all I do is sit in my room and watch movies and TV – it's just not enough," he said.
Doctors have recommended that he try a medication called etanercept, part of a class of "biologic" medications manufactured in living organisms such as plant or animal cells. Etanercept costs about $20,000 a year to treat a patient with moderate to severe psoriasis. After repeated attempts to get medical coverage for the expensive treatment, Groulx said, "I kind of gave up."
The new biologic medication used in the NEJM study is awaiting Health Canada approval. But once it reaches the market, chances are it won't be cheap. Typically, biologics incur high costs in research and development, as well as the labs required to manufacture them.
Nevertheless, provincial health plans and private insurers may give coverage of the new medication "high consideration" because of the study findings, said Dr. Neil Shear, head of dermatology at Sunnybrook Health Sciences Centre in Toronto and a spokesperson for the Canadian Dermatology Association.
Shear described the treatment results of the experimental medication as "impressive" compared to those for etanercept, which has a 44-per-cent success rate in reducing clinical signs of psoriasis by 75 per cent.
But he clarified that a 75-per-cent reduction in psoriasis may mean different things to different patients, "depending on how abnormal you were to begin with." Patches of inflamed skin might become thinner or less scaly with treatment, he said, "but you might still have a fair amount of psoriasis on your body."
Side effects of the new biologic medication were minimal in the study, consisting mainly of yeast infections, coughs, colds, headaches and diarrhea. Since treating psoriasis has been shown to prevent diseases such as Type-2 diabetes and cardiovascular disease, Shear said, "you're way safer having this [biologic] than having psoriasis."
He added that trials on two similar biologic medications by manufacturers Amgen and Eli Lilly are nearing completion.
Van Voorhees noted that the long-term effects of these experimental medications remain unknown. But "that is inherently the risk of a new medication," she pointed out.