Dutch researchers recently studied a new protocol for treating systemic juvenile idiopathic arthritis (sJIA), the most serious form of arthritis in children. Instead of starting young patients on corticosteroids – the time-honored approach – researchers used the biologic drug anakinra (Kineret) as a first-line therapy shortly after diagnosis. Within three days of getting the medication, 18 of the 20 children in the study no longer had a fever and within a month, most showed a 90 percent improvement in symptoms. For many, the positive effects persisted. After three years, most were in remission and off medication.
"That these kids were 90 percent better after three months is a really rapid and robust response. In the past, we were talking about (achieving) a 30 percent improvement," says Norman Ilowite, MD, chief of the division of rheumatology at The Children's Hospital at Montefiore and professor of pediatrics at Albert Einstein College of Medicine in the Bronx, New York.
Anakinra belongs to a class of biologic drugs called interleukin (IL) inhibitors, which block inflammatory proteins, especially IL-1 and IL-6. Other IL inhibitors used to treat sJIA include canakinumab (Ilaris) and tocilizumab (Actemra). All were once considered drugs of last resort, prescribed only after corticosteroids and other medications failed to improve a child's symptoms.
Daniel Lovell, MD, associate director of the division of rheumatology at Cincinnati Children's Hospital Medical Center and professor of pediatrics at the University of Cincinnati, has been using IL-inhibitors as a first-line therapy in his own patients for over a year.
"We have very sick kids who got measurably better after the first dose. In some cases, the response is so profound that even if kids do need medication, they don't look or act sick, their labs are fine – it's impossible to tell they're sick. It's truly miraculous what can be accomplished when the treatment is tailored specifically to the mechanism of the disease."
The Dutch study reinforces the American College of Rheumatology's 2013 JIA treatment guidelines, which recommend anakinra as a first-line therapy for children with active systemic disease. The updated ACR recommendations also suggest using IL-inihibitors, including tocilizumab and canakinumab, when other drugs fail to improve symptoms.
Carol Wallace, MD, a professor of pediatrics at the University of Washington School of Medicine and Seattle Children's Hospital notes, "These are very sick children, and first-line therapy should be a biologic such as anakinra because they need aggressive treatment right away."
Treating with a biologic first may also avoid the toxic and often irreversible side effects of corticosteroids, such as diabetes, severe osteoporosis and slowed growth.
"We now know that steroids are fraught with problems and are not a high-quality approach for some patients. Biologics, on the other hand, have remarkably few side effects and can make an enormous difference in a child's life," Dr. Wallace says.
What parents need to know about IL-inhibitors
Every child with systemic JiA is different and experts recommend that parents discuss the effectiveness, safety, cost and administration of IL-inhibitors with their pediatric rheumatologist.
Do they really work? Not all patients in the study responded to anakinra. Two needed corticosteroids to control inflammation and five relapsed. One child later died of macrophage activation syndrome, a severe complication of sJIA.
"This was a small study – definitely not a blockbuster – because there was no control group (children treated with a different drug),” Dr. Ilowite says. “If some children had received corticosteroids, would they have had the same response rate (as the anakinra patients)? We don't know the answer, but I do believe it's the right thing to treat earlier without using steroids, or even nonsteroidal anti-inflammatories (NSAIDs) first."
Both canakinumab and tocilizumab were approved for use after large-scale, international clinical trials found them effective for kids with sJIA. Most pediatric rheumatologists agree that having more treatment options can only benefit patients earlier.
Are they safe? IL-inhibitors work by suppressing the immune system and can increase the risk of infection while kids take them. It takes about 10 years, however, to determine whether medications increase the risk of cancer or other serious illnesses in the future. Most IL-inhibitors are newly approved and haven't undergone long-term studies, although such studies are underway.
"The data we have suggest that (IL-inhibitors) are very safe – certainly safer than corticosteroids – but our information right now is very limited," Dr. Ilowite says.
Are they expensive? Unlike canakinumab and tocilizumab, anakinra isn't approved for sJIA. Although it's been used to treat adult rheumatoid arthritis (RA) for nearly 15 years, insurers may not cover the $3,000 per month costs in children. (Canakinumab, in contrast, may cost as much as $16,000 per dose but is usually covered by insurance).That's one reason having several treatment options is important, Dr. Lovell says.
"Any of the IL-inhibitors is a good option to replace corticosteroids, not just anakinra. No drug is effective in 100 percent of children, and kids who don't respond to one may respond to another," he notes.