Stem-cell therapy enabling cartilage regeneration has been piloted by several groups and companies but has not yet been authorized in Europe. Most efforts to develop stem-cell treatments have used autologous stem cells that have been isolated from the same animal and re-injected into the damaged joint. These studies have shown improvement, but benefits have generally only lasted for <12 months. The reason for this is probably that affected pure breeds have genetic defects in genes that lead to the development of weak cartilage that is easily eroded. In contrast, our solution for OA treatment (ADStem) contains stem cells from healthy donors with no history of OA. Since these cells are not immunogenic, the cells can be injected into the affected animal's joint without the risk of immunoreactions in a process called allogenic stem-cell treatment. ADStem is a single injection which is currently being tested in GCP trials providing a novel treatment option for non-specialist veterinary centres.