Arcalyst Receives New Indication for Rare Inflammatory Disorder

December 21, 2020 – The U.S. FDA has approved a new indication for Arcalyst (rilonacept), manufactured by Regeneron. The drug is now indicated for maintenance of remission of deficiency of interleukin-1 receptor antagonist (DIRA) in adults and pediatric patients who weigh at least 10kg (22 pounds).

DIRA is an ultra-rare inflammatory disease that occurs due to a mutation in the IL1RN gene. The mutation leads to underproduction of interleukin-1 receptor antagonist (IL-1Ra) protein, which is needed to control the body’s inflammatory responses. The absence of sufficient IL-1Ra leads to life-threatening systemic inflammation. Symptoms can manifest as early as the first weeks of life.

In a clinical study, six pediatric patients who had previously benefited from daily Kineret® (anakinra) injections achieved and maintained remission on Arcalyst. Remission was defined as achieving thefollowing: a diary score of less than 0.5 (reflecting no fever, skin rash, and bone pain); C-reactive protein (CRP) serum levels (a measure of inflammation in the body) less than 5mg/dL; absence of objective skin rash; and no radiological evidence of active bone lesions.

Recommended pediatric dosing under the new indication is 4.4mg/kg of body weight (not to exceed a total dose of 320mg) administered once weekly as one or two subcutaneous (SC) injections. Recommended dosing for adults is 320mg once a week, administered as two separate SC injections on the same day.

First FDA approved in 2008, Arcalyst is also indicated to treat cryopyrin-associated periodic syndromes (CAPS), including familial cold auto-inflammatory syndrome and Muckle-Wells syndrome, in adults and children 12 and older.