Because veterinary medicine is less (oppressively) regulated than human medicine, animals are benefiting from stem cell therapies that are safe enough for human use but nonetheless still illegal to commercially develop in the US: "In a very unusual breakthrough, a stem cell treatment for racehorses is ready to be tried ... on you. British scientists pioneered a technique in horses where an individuals' own stem cells are grown outside the body, then injected into the damaged tendon. There will be a clinical trial in the UK in which 24 human patients will undergo this radical new stem cell treatment for similar tendon injuries. We'll tell you about the proven benefits in racehorses so you'll understand the possible benefits in people. The test subjects who join the clinical trial will be in the unique position of enjoying a medical procedure that is years behind the veterinary equivalent. If human beings have the same barely believable 80% recovery rate, this will be a leap forward for sports medicine. ... The reason animals can get commercial drugs and treatments faster than people in the US and other Western countries is simple: there is enormous oversight in human medical research. Veterinary research is comparably simple. According to the FDA, bringing a new drug to market for humans requires pre-clinical laboratory tests, animal tests, and human clinical trials. Each one of those steps costs money, lots and lots of it. Approval for veterinary drugs is simpler, requiring a single study that proves the drug is safe and effective. Because of regulatory difference, progress on animal medical research can move very quickly compared to human research."

Link: http://singularityhub.com/2011/03/10/uk-stem-cell-company-cures-race-horse-tendons-humans-next/