Intraorticular treatment of osteoarthritis using autologous interleukine-1 receptor antagonist (IL-1Ra) conditioned serum

Basic research over the past decade has shown the cytokine interleukine1 (IL-1) to be one of the major mediators in the pathogenesis of osteo-arthritis in terms of its activation of an inflammatory response as well as of cartilage degradation. Inactivation of this key substance may therefore be useful in the the treatment of osteoarthritis. For several years an autologous IL-1 receptor antagonist (IL-1-Ra) conditioned serum has been available for the intraarticular therapy of osteoarthritis (Orthokin(R)). In this approach patient serum is artificially conditioned to synthetize a high amount of IL-1-Ra. The conditioned serum is reinjected into the affected joint in 6 to 8 portions over 3-4 weeks. Preliminary results from prospective multicentric studies of approximately 1000 treated knee joints with osteoarthritis grade I-III according to the Kell-gren classification reveal that 70-75% of the patients report pain relief ranging from 50-100%. After 3.5 years 35-40% of the patients still report benefit from the treatment. No serious side effects were observed in more than 6000 injections. The intraarticular application of autologous, artificially conditioned serum appears to be an alternative to standard conservative treatments of osteoarthritis.