IRAP is a new and effective intra-articular treatment for joint disease marketed by Arthrex VetSystems in the USA.  The product was originally developed in Europe, and has been used extensively in Germany.  IRAP is an anti-inflammatory protein that counteracts the destructive effects of inflammatory proteins such as Interleukin-1 (IL-1) that are produced within inflamed or arthritic joints.  The  system has been designed to stimulate the horses’ own white blood cells to produce anti-inflammatory mediators and enzymes, specifically Interleukin 1 receptor antagonist protein (IRAP), which can reduce the inflammation present as a result of degenerative joint disease.  Treatment with IRAP utilizes progressive gene therapy to combat osteoarthritis in your horse.

The process of harvesting is quite simple and can be performed as an outpatient and/or potentially on the farm.  Blood is collected from the jugular vein and incubated for 24 hours in special syringes that contain glass beads that induce the white blood cells present in the blood to produce and secrete therapeutic proteins, namely, After 24 hours the blood is centrifuged and the serum is separated from the red blood cells. The protein rich serum is then split into 3-6ml doses and the separate doses are frozen for use at a later date

Typically each collection produces enough serum for between 3-5 injections. It is important to note that the injections are only suitable to treat the horse from which the original blood was collected. The injections can be stored for up to 12 months from the date of collection.

Degenerative joint disease is one of the biggest causes of poor performance and a decreased competitive lifespan in the horse. This is true for all types of equine athletes, from racehorses to dressage and show jumping horses. Both young and old horses can be affected by degenerative joint disease resulting in a loss of athletic ability and possible early retirement.

When injected into a joint, the IRAP protein rich serum stimulates a response from cartilage cells, through a process of cell division and increased cell recruitment. This is actually what sets IRAP apart from other intra-articular treatments for joint disease. The fact that IRAP stimulates cartilage cells means that it has a disease modifying component as well as an anti-inflammatory component. The serum also contains cytokines that act to reduce inflammation within the joint. In addition there are other anti-inflammatory proteins produced during the incubation process that work synergistically with the cytokines to further reduce the inflammation within the diseased joint.

What does the treatment with IRAP involve?

The therapy involves three joint injections at 7-14 day intervals. Most positive effects are seen after the second and the third treatment. The majority of horses will be sound after the third injection. In our hands, more than 90% of horses have returned to soundness after IRAP therapy. After injection, we routinely bandage the joint if possible for 2 days, and the horse should be kept on 3 days of strict stall rest, followed by a period of of hand-walking (30-45 minutes).  Once the course of injections and the final hand-walking period is completed, horses should receive one week of ridden walk exercise, followed by one week of ridden walk and trot, before returning gradually to regular training program