TORONTO — It’s known as “the disease of a thousand faces” and for good reason — lupus can affect so many divergent areas of the body that no two people are afflicted with exactly the same symptoms, posing a challenge for doctors trying to tailor an individual’s treatment.
Now, for the first time in almost 50 years, Canadians with systemic lupus erythematosus have a potential new treatment option with Health Canada’s approval of the drug Benlysta (belimumab).
Lupus is an autoimmune disease which affects an estimated one in every 1,000 Canadians, nine out of 10 of them female, with age of onset typically between the late teens and early 40s.
While the exact cause hasn’t been pinned down, it’s known that the potentially deadly disease is the result of the immune system having gone off script, as it were.
“The immune system, rather than acting as a protector, in these people it actually turns on itself and acts to injure,” said Dr. Murray Urowitz, a Toronto rheumatologist whose research focuses on the disease. “So patients produce antibodies — proteins — against various constituents of their own body.”
When those antibodies react with different tissues — and that can include the skin, joints, heart, kidneys and brain — it ignites a process of inflammation, Urowitz said Tuesday. “Lupus is an inflammation, like a little fire that begins in many organs in the body.”
People with lupus feel lousy much of the time, with the extreme fatigue and the achiness reminiscent of a nasty flu. But depending what organs are also affected, patients can suffer a host of other symptoms: “If it’s the brain, they could have psychosis, cognitive disability — not being able to think clearly — or they could have seizures,” he explained.
Inflammation of the heart lining can cause severe chest pain, while inflammation of the kidneys can lead to renal failure.
Rowena Rodriguez of Toronto was just 19 and about to start her first year at Ottawa’s Carleton University when she began experiencing severe joint pain and spiking high fevers; much of her hair fell out and 30 pounds dropped off her five-foot-two, 115-pound frame in three weeks.
She also developed lupus’s tell-tale butterfly-shaped rash across the bridge of her nose and both cheeks.
Despite her symptoms, several doctors dismissed her symptoms as flu. But after months in the hospital with myriad symptoms, Rodriguez was finally diagnosed with lupus.
Because some of the medications she takes suppress her immune system, she has had excruciating shingles four times and now is suffering painful nerve damage in much of one leg.
“You really feel like you’re constantly at war with yourself,” Rodriguez explained. “Your body becomes like a battlefield.”
Standard treatments range from anti-inflammatory pain killers like ibuprofen to potent but often toxic corticosteroids and medications to suppress the immune system. While their mechanism of action isn’t well understood, antimalarial drugs can also be effective in tamping down the effects of lupus in milder cases.
“All of those treatments taken together have actually resulted in significant improvement in patients with lupus,” said Urowitz. But a significant group of patients do not respond or can’t tolerate their side-effects. “And that’s the group of people that we are always trying to find something new for.”
Benlysta, developed by Human Genome Sciences and jointly marketed with GlaxoSmithKline, targets a protein called BLyS (B-lymphocyte stimulator) that nurtures the cells that make the antibody underlying the inflammatory response seen in lupus.
“So we’re not wiping out the whole immune system; we’re targeting one particular part only,” he said. “That was the innovation.”
The injectable drug is intended to act as an adjunct therapy for patients who are seeing too little benefit from other treatments, he said. “So it’s not a cure, but it’s an added treatment.”
So far, Benlysta is indicated for patients with milder disease: it has not been evaluated in subjects with severe kidney or central nervous system inflammation, although such clinical trials are planned, says its maker.
But even for milder cases of lupus, the medication has had a lukewarm response in some quarters. While a committee of the U.S. Food and Drug Administration backed approval of the drug last year, some of the panel’s 15 members voiced reservations about its effectiveness.
The drug is designed to treat flare-ups and pain caused by lupus, but experts said it worked in only a subset of patients and was not effective against the deadliest forms of the disease.