First Oral Biologic Drug for Rheumatoid Arthritis Treatment
In November 2012, the U.S. Food and Drug Administration (FDA) approved tofacitinib (Xeljanz) to treat adults with moderate to severe RA who have an inadequate response to or cannot tolerate methotrexate. Xeljanz, which is classified as a JAK inhibitor, works by blocking enzymes called Janus kinases (JAKs) that play a role in joint inflammation in people with RA. In clinical trials, tofacitinib was shown to reduce rheumatoid arthritis symptoms.
Tofacitinib is administered in pill form and is taken twice a day. It can be used alone or in combination with methotrexate or another non-biologic DMARD (disease-modifying anti-rheumatic drug) like sulfasalazine, leflunomide, or hydroxychloroquine. It should not be used with biologic response modifiers (BRMs), azathioprine, or cyclosporine.
Approval of tofacitinib includes a Risk Evaluation and Mitigation Strategy (REMS) to alert patients and health care providers who prescribe the drug to potential serious risks. Tofacitinib packaging contains a Boxed Warning due to an increased risk for serious infections, including tuberculosis, and certain cancers, such as lymphoma.
Side effects of tofacitinib include diarrhea, headaches, respiratory infections, and inflammation of the nose and throat. The drug also can affect cholesterol levels and liver enzymes and cause low blood counts. Studies to determine the long-term effects of tofacitinib and evaluate two doses of the drug are ongoing.