FDA Approves Enbrel for Limiting Bone and Joint
Damage in Psoriatic Arthritis
First posted August 28, 2003
The U.S. Food and Drug Administration (FDA) approved on Monday a new use for the biologic drug Enbrel; it now can be used to limit the bone and joint damage associated with psoriatic arthritis. In January 2002, Enbrel became the first biologic approved for psoriatic arthritis; the study looked into the possibility of further benefits with Enbrel.
The FDA's decision was based on a phase III study evaluating patients with active psoriatic arthritis. Enbrel demonstrated inhibition of joint damage over a one-year study period, while x-rays of patients receiving a placebo showed progressive joint destruction.
The new label use is significant because after 10 years with psoriatic arthritis, more than half of patients already have five or more joints involved. Also, other drugs, such as methotrexate, steroids and NSAIDS can improve inflammation and pain, but they may hide the progression of joint damage.
Enbrel, manufactured by Amgen and co-marketed by Wyeth, is given by self-injection under the skin. The medicine works by blocking a chemical in the immune system that overstimulates inflammation. This chemical is called "tumor necrosis factor-alpha" (TNF-alpha), an immune-system chemical messenger.
Enbrel is approved for rheumatoid arthritis, juvenile rheumatoid arthritis and ankylosing spondylitis, a disease that causes inflammation in the spine. The company also filed in June for approval for psoriasis treatment. FDA approval typically takes about one year for new drugs; however, approval of drugs already on the market may take less time, and some people with psoriasis are already receiving Enbrel treatment from their doctor "off-label" (without FDA approval).
Injection site reactions (redness, itching, pain, and swelling) were the most common short-term side effect. Serious infections, including some fatalities, have been reported with the use of Enbrel. The infections often occurred in patients using other medications that suppress the immune system, like methotrexate. Serious infections are rare in patients taking Enbrel alone. Also, rare cases of tuberculosis have been observed in patients taking medications that target TNF-alpha. Enbrel�s safety and side effects continue to be monitored by Amgen and Wyeth and the FDA.
| 
