People suffering from the autoimmune disease lupus might soon have a new drug to turn to, a clinical trial suggests.
Anifrolumab is a lab-created antibody that blocks type 1 interferon, a biochemical that activates an immune response in humans, explained lead researcher Eric Morand, head of the Monash Health School of Clinical Sciences in Melbourne, Australia.
The new drug triggered a significant reduction in lupus symptoms in 48% of patients after one year, compared with 32% of patients receiving a placebo.
"We've known for a long time that about 80% of lupus patients have a detectible signature in their blood showing they have too much interferon in their system," Morand said.
Anifrolumab, which blocks the type 1 interferon receptor that all immune cells share, shows that overproduction of this biochemical does indeed play a major role in lupus, he said.
"This drug, which does only that one thing, was associated with a dramatic improvement in patients' outcomes compared to placebo," Morand said.
Based on results from this and earlier trials, pharmaceutical company AstraZeneca intends to file for U.S. approval of anifrolumab sometime within the first half of next year, Morand said.
"They feel optimistic because across all three trials, virtually all of the measures stack up and look the same," he said.
AstraZeneca funded this trial.
About 1.5 million people in the United States have lupus, and more than 5 million worldwide have it, researchers said in background notes. Nine out of 10 patients with lupus are women.
Lupus causes the immune system to turn against the body, causing inflammation and pain. People most commonly suffer from rash, painful or swollen joints, headaches, extreme fatigue, anemia, fever and swelling in the feet, legs and hands, according to the Lupus Foundation of America.
Lupus also causes sustained inflammation in the internal organs, and about 10% of people diagnosed with the disease die within a decade, researchers said.
In this international three-year clinical trial, half of 362 patients received anifrolumab and the other half received a placebo.
An earlier clinical trial of anifrolumab did not return positive results because doctors had set a goal of total improvement in at least one organ system affected by lupus, Morand said.
This trial shifted the goal posts, instead aiming for partial but significant improvement across all the organ systems being harmed by lupus, he said.
Researchers said the drug met that goal. For example, many patients with a lupus-provoked rash found that their skin cleared after starting anifrolumab.
"The most obvious improvements were in severe lupus skin disease. It's obvious because you and the patient can both see it," Morand said. "There are many reports from investigators of skin disease almost vanishing swiftly."
Patients also needed fewer doses of steroids to treat their symptoms, and experienced symptom flares less frequently.
No one had to stop taking anifrolumab due to side effects, which were mainly caused by the drug's inhibition of immune response against viral infections, Morand said. About 7% of patients suffered an outbreak of shingles and 12% came down with bronchitis.
However, there was one death from pneumonia in the group taking anifrolumab.
The findings were published Dec. 18 in the New England Journal of Medicine.
"There's been very little good news in lupus for a long, long time," Morand said, noting that the trial results show that "we're learning how to do this better, and hopefully more drugs will succeed in the coming years."
An editorial published with the study noted that across three clinical trials, results for most of the primary and secondary goals showed that anifrolumab did perform better than a placebo.
"Given the need to bring drugs to patients with SLE [systemic lupus erythematous], the lupus community has urged regulators to consider trial designs that allow greater flexibility in defining success," wrote editorialists Dr. Jane Salmon from Weill Cornell Medicine and Dr. Timothy Niewold from NYU School of Medicine, both in New York City.
"Such strategies might accelerate drug development in lupus until we have available universally accepted response measures and biomarkers that allow grouping of patients with SLE according to biologic pathways that drive their disease," the editorial concluded.
The Lupus Foundation of America has more about lupus.