By blocking the action of a certain protein in the body that causes inflammation, Arcalyst can help treat a rare group of autoinflammatory conditions known as cryopyrin-associated periodic syndromes. This prescription drug comes as an injection that is given once a week. Coughing, reactions at the injection site, and reduced sensitivity to touch are potential side effects.
Arcalyst® (rilonacept) is a prescription medication approved to treat cryopyrin-associated periodic syndromes (CAPS) in adults and children as young as 12 years old. CAPS are a rare hereditary group of autoinflammatory conditions, including familial cold autoinflammatory syndrome (FCAS) and Muckle-Wells syndrome (MWS).
Arcalyst is manufactured by Regeneron Pharmaceuticals, Inc.
Arcalyst works by blocking the actions of interleukin-1 beta (IL-1β), a protein of the immune system that causes inflammation in the body. People with CAPS have increased levels of IL-1β, which leads to inflammation in the body. By blocking the action of IL-1β, Arcalyst reduces the inflammation and symptoms associated with CAPS.
Arcalyst has been studied in people with CAPS and has been shown to reduce the symptoms of the condition. In one study, 96 percent of people given Arcalyst had at least a 30 percent self-reported decrease in their symptoms over 6 weeks, compared with 29 percent of those given a placebo (a product that does not contain any active ingredients). Most people saw an improvement in their symptoms within several days of starting treatment.