The FDA has approved anakinra (Kineret Amgen Inc, Thousand Oaks, Calif) as adjunctive therapy for reduction in signs and symptoms of moderately to severely active rheumatoid arthritis (RA) in patients 18 years of age or older in whom one or more disease-modifying antirheumatic drugs (DMARDs) have failed. Anakinra is indicated for use alone or in combination with DMARDs other than anti–tumor necrosis factor (TNF) therapies.

Safety and effectiveness of were evaluated in three randomized, placebo-controlled trials of 1392 patients at least 18 years of age with active RA. A fourth study assessed the drug's safety in 1414 similar patients who were DMARD free or received concurrent medications, including some DMARDs.

Anakinra was studied in combination with DMARDs (other than anti-TNF therapies) or as monotherapy. Results were assessed using American College of Rheumatology (ACR) response criteria. In all three studies, patients taking anakinra were more likely to achieve scores of ACR 20, ACR 50, or ACR 70 than patients treated with placebo. In the largest study, patients with RA receiving a stable dose of methotrexate were also treated with anakinra, 100 mg/d (the recommended dosage), or placebo. After 3 months, 34% of patients receiving anakinra and 24% patients receivingon placebo had ACR 20.

Adverse reactions associated with the drug included increased incidence of serious infections (2% in those taking the drug vs <1% in those taking placebo) and neutropenia. Preliminary data suggest a much higher rate of serious infections and neutropenia when anakinra is used with an anti-TNF therapy.