[Treatment of rheumatoid arthritis by interleukin-1 receptor antagonist].

PURPOSE

Interleukin -1 receptor antagonist ( IL-1Ra ) is a new option among biotherapies against rheumatoid arthritis ( RA ).

THE AIM

of this review is to recall the rationale of use of IL-1Ra and to analyse the results available in the current literature.

CURRENT KNOWLEDGE AND KEY POINTS

Pathophysiological data of RA give a specific position for IL-1 as a potential target for immunotherapy in this disease, confirmed in animal models. Phase II and III studies with IL-1Ra (Anakinra) demonstrated clinical efficacy versus placebo (42% responders in ACR 20 in Anakinra + methotrexate, and 23% in the placebo + methotrexate group at 24 weeks) and a structural effect (slowing of radiological progression at six months). Anakinra has obtained an European license and is indicated in RA not controlled by methotrexate, in daily subcutaneous administration (100 mg/day), in combination with methotrexate. Tolerance is fair; the most frequent side effect is represented by injection site reactions.

FUTURE PROSPECTS AND PROJECTS

This ambulatory biotherapy offers new perspectives in combination with other slow acting drugs as well as biologic agents such as anti-TNF, currently under evaluation.