An overproduction of the endogenic protein “Interleukin-I” plays an important role in the joint inflammation, in the end leading to progressive destruction of articular cartilage. Here IRAP therapy offers complete new possibilities, and is also successful in cases where previous treatment methods encounter their limits. The objective of IRAP therapy is to neutralize the interleukin produced in the affected joint through endogenic defense mechanisms. First of all, a blood samle is taken and treated in a special process for this purpose. The treated endogenic serum will later be injected into the affected joint and there inhibits inflammation and chondroclasis. The path to regeneration of cartilage is cleared as a result. The decivise advantage of this form of therapy is that it concerns an endogenic product. Side effects are absent.