The United States Food and Drug Administration (FDA) Center for Veterinary Medicine recently approved Tildren for use in horses in the United States. For those of you who are unfamiliar with Tildren, it is a pretty remarkable drug that has been used around the world for nearly two decades now to treat bone-related lameness in horses.
According to its maker CEVA, Tiludronic acid (also called Tildren) is a bisphosphonate therapeutic drug which exerts activity on bone metabolism. The main pharmacological property of Tildren is to reduce bone resorption by inhibiting the activity of osteoclasts (cells that break down bone.) Some readers may be familiar with bisphosphonates since they are widely used in women to slow the progression of osteoporosis.
Tildren essentially acts as a regulator of bone remodelling in all situations involving excessive bone resorption, such as arthritis or navicular syndrome in horses. This regulator effect is not associated with a negative effect on bone formation or bone mineralization at the recommended therapeutic dosage. Tildren is officially labelled to treat navicular syndrome, but veterinarians who have been able to obtain it from overseas report excellent results with its application for arthritis, ringbone, and kissing spines. Basically- if your horse’s lameness is bone-related, Tildren may be able to help!
Although Tildren can be given once daily for 10 days to achieve the therapeutic effect, it is much safer and reportedly more effective to give it once, but slowly over 1 to 3 hours’ time. This can be easily accomplished by diluting the medication in intravenous fluids and then letting it run in on an IV drip.
Side effects are few and far between- some horses have reportedly become colicky after the treatment, but the colic is usually mild and resolves spontaneously on its own. Also, it is not approved for use in young, growing animals under 2 years of age due to its competitive binding of Calcium.
Tildren works slowly over time with effects most commonly being reported at 5 to 8 weeks post administration. However, some horse owners report effects in as little as 2 days to 2 weeks following a Tildren injection! The effects are long-lived and often last for several years. Most horses that receive Tildren do not get a second dose however no deleterious side effects have been described to date as a result of repeated dosing.
Sounds like a wonder-drug… right? Some may wonder, “where has it been all my life?!” The FDA has rigorous approval procedures in which a drug manufacturer must prove product safety and efficacy prior to it being available in the United States. As a result, Tildren has, until recently, been unavailable here. Those who have imported Tildren under the federal FDA personal importation policy have paid high prices. Tildren sells for far less in other parts of the world than it does in the USA. This is due not only to opportunistic “supply and demand” mark-up, but also to overseas shipping costs and administrative import paperwork.
Now that Tildren is available here, hundreds of lame horses may be kicking up their heals once again as veterinarians everywhere will begin to stock it! How many readers have horses that have received Tildren? Any stories that you wish to share?
