FDA has approved Arcalyst (rilonacept) injection to treat recurrent pericarditis and reduce the risk of recurrence in adults and children 12 years and older.  

Recurrent pericarditis is characterized by a remitting-relapsing inflammation (or symptoms that fluctuate in severity) of the pericardium, a thin tissue sac surrounding the heart. Pericarditis often causes chest pain, which can be sharp. This chest pain worsens when patients take a deep breath.  

The efficacy and safety of Arcalyst were evaluated in a double-blind, randomized study enrolling 86 patients with symptomatic pericarditis recurrence. Everyone first received Arcalyst for 12 weeks. After that point, one half of patients continued to receive Arcalyst 160 mg weekly and the other half received a placebo. The primary effectiveness endpoint was the time to first pericarditis recurrence. Results showed that 23 (74%) patients in the placebo arm had a recurrence compared to two (7%) patients on Arcalyst, both of whom had temporarily stopped treatment.  

Serious, life-threatening infections have been reported in patients taking Arcalyst. Patients with active or chronic infections should not take the drug. Patients should also avoid live vaccines while taking Arcalyst.  

Arcalyst received orphan drug designation for the treatment of recurrent pericarditis. 

FDA granted the approval of Arcalyst to Kiniksa Pharmaceuticals (UK) Ltd. Arcalyst was first approved in 2008 to treat Cryopyrin-Associated Periodic Syndromes, including Familial Cold Auto-inflammatory Syndrome, and Muckle-Wells Syndrome in patients 12 years and older, and to maintain remission of Deficiency of Interleukin-1 Receptor Antagonist in patients weighing 10 kg (22 lbs) or more.