Novartis announced on Friday that the U.S. Food and Drug Administration (FDA) had granted approval for its drug Ilaris to treat severe childhood arthritis.

Ilaris is the first treatment for systemic juvenile idiopathic arthristis (SIJA) that can be administered once a month via injection under the skin, according to the Swiss-based pharmaceutical industry.

The approval follows two successful phase III clinical trials for SIJA. SIJA affects up to 15 children per 100,000 in the United States and is the most severe form of childhood arthritis without known cause. The drug is approved for use in children aged two and older

In the first Phase III trial, 84 percent of children taking Ilaris had a 30 percent improvement in symptoms as judged by a nationally approved pediatric scale. In contrast, only ten percent kids on the placebo reported an improvement.

The second study showed a quarter of SIJA patient on Ilaris were able to reduce their use of corticosteroids, which have serious adverse effects like growth suppression and osteoporosis. In this trial, Ilaris was given once a month and reduced the occurrence of painful arthritic "flare-ups."

Ilaris is an interleukin-1 beta (IL-1 beta) inhibitor - the first approved for use with SIJA - that targets inflammation. Novartis is pursuing its use in a number of rare autoinflammatory disorders. It is already approved in over 60 countries, including the U.S. and EU, for treating cryopyrin-associated periodic syndromes (CAPS), a rare but sometimes fatal genetic disorder with escalating symptoms from joint pain, fatigue, and fever, to bone deformity, vision loss, and renal failure.

Novartis Global. (2013). Novartis drug Ilaris® approved by FDA to treat active systemic juvenile idiopathic arthritis, a serious form of childhood arthritis [Press Release]. Retrieved from http://www.novartis.com/newsroom/media-releases/en/2013/1700796.shtml.