Anakinra for rheumatoid arthritis: A modest benefit with some risk

January 21, 2009

New research supports a modest beneficial effect of anakinra for rheumatoid arthritis patients, but warns against potential risks for serious infections and its use with other biologic medications.

Rheumatoid arthritis is a chronic inflammatory disease affecting as many as one in 100 people worldwide. It affects the joints, making them stiff and painful. Anakinra is one of a new breed of arthritis drugs licensed in the past decade called 'biologics'. The drug is the first to target the immune protein IL-1, thought to be partly responsible for inflammation in arthritis patients. It is given by daily injection.

In a Cochrane Systematic Review of five recent anakinra trials involving 2,876 patients, researchers found anakinra reduced pain and stiffness in patients, and helped to improve joint function, when compared to placebo. However, while around a quarter of patients experienced improvement in their symptoms as a result of taking anakinra, the researchers say the improvements are notably less than those seen with other biologics.

In addition, there were more injection site reactions with the use of anakinra and the rate of serious infections with anakinra was approaching statistical significance when compared to placebo. "We would recommend caution with the use of anakinra for rheumatoid arthritis, especially with the only modest beneficial outcomes compared to other biologic medications studied for rheumatoid arthritis," said lead researcher Dr. Marty Mertens of the University of Minnesota in the US.

One study included in the review investigated the combination of anakinra with another biologic medication, etanercept. This found no benefits in arthritis outcomes, but did show a significant increase in the number of serious adverse events. "On the basis of these results, we recommend that doctors avoid combining biologic medications with anakinra when treating patients with rheumatoid arthritis,' said Mertens.

Dr. Mertens thinks more research is required to better inform patients and doctors about the safety of the drug: "We have only limited data on the safety of anakinra, and need more long-term studies to evaluate this, especially the potential for increased risk of serious infections."

Source: Wiley