The U.S. Food and Drug Administration has accepted Centocor Inc.'s application to approve infliximab (Remicade) for the treatment of psoriatic arthritis.
Already approved for use in rheumatoid arthritis and Crohn's disease in North America, the European Union, and Japan, infliximab was recently approved for use in psoriatic arthritis by the European Commission.
Centocor, a wholly owned subsidiary of Johnson & Johnson, based its application on two double-blind, placebo-controlled studies involving a total of 304 patients with psoriatic arthritis. In one study, 65% of the patients on infliximab (5 mg/kg) achieved at least a 20% improvement, according to American College of Rheumatology (ACR20) criteria at week 16.
In the second study, some patients taking 5 mg/kg of infliximab began showing improvement as early as week 2. By week 14, 58% of the patients taking infliximab and only 11% of the patients taking placebo achieved ACR20 improvement. The Psoriasis Area and Severity Index score improved by 75% in 63.9% of the infliximab patients and only 2.3% of the placebo patients. Both differences were statistically significant.
Patients with psoriatic arthritis tolerated infliximab well in these studies, with an elevation in liver function tests being the most common abnormality associated with the drug, which inhibits tumor necrosis factor alpha. Investigators noted no deaths, cases of tuberculosis, or other opportunistic infections among the patients taking infliximab in these studies.