Tildren Is Making Greater Inroads In The United States


The signs are familiar and common yet never easy to watch: short, stubby strides, marked soreness, the head-bobbing lameness. When those kinds of symptoms are caused by navicular syndrome, treatment options have been depressingly slim. But in the early part of this century, veterinarians with well-connected European colleagues heard whisperings about, or actually obtained, a new drug that appeared to work wonders at restoring soundness in horses with bone-related lamenesses. From grand prix jumpers with slight changes in their legs to backyard pleasure horses stricken by navicular, a drug called Tildren appeared to slow the bone deconstruction process. Today, Tildren has become a one-dose ticket to recovery or prevention for many horses.

The problem? In the six years since people started hearing about the medicine, the U.S. Federal Drug Administration has yet to approve Tildren for use in this country. That may change soon, however, if the results of an intense, nationwide study currently underway and being funded by the drugʼs founder, Ceva Sante Animale in France, go according to expectations. FDA approval of the drug would open up access to Tildren for veterinarians and likely decrease the price of the medicine, making the drug available to a greater number of horses and owners. Perhaps because of its international origins, Tildren still isnʼt well known. In France, Ceva is a leading science and research company that has introduced new drugs and therapies for everything from cows and poultry to dogs and swine and horses. But to obtain Cevaʼs Tildren in the United States, licensed veterinarians are required by law to fill out separate applications for each horse they think qualifies for the medicine, a process that can take six to eight weeks from the time a veterinarian diagnoses a horseʼs condition to when he or she has Tildren ready to administer.

An Intravenous Intervention Upon arrival, the drug maintains its mystique. At Homestead Equine Hospital in Pacific, Mo., veterinarian Mark Cassells remembered being a bit perplexed when he ordered Tildren for the first time. The package was a little blue box that, when unwrapped, revealed rows of little bottles and vials and a bunch of French or German directions on how to administer it. "None of the instructions are in English," said Cassells, who started ordering Tildren for his clients a few years ago after hearing about the drug at a conference. "There are 20 vials inside, 10 that contain the drug in a powder form and 10 that contain the dilutant," Cassells said. "You mix up one vial of powder and one vial of dilutant every day to administer intravenously, or you can mix up the entire thing and administer it in a one- time intravenous dose." Most veterinarians prefer the one-time intravenous dose. Instead of oral medicine, which gets absorbed more slowly or not at all because it goes through the digestion system, intravenous Tildren soaks into a horseʼs bones like water seeping into a sponge. Controlling The Damage This is where Tildren goes to work. In a horse with navicular or any other chronic bone condition—ringbone, for instance, or osteoarthritis of the hock—Tildren inhibits bone deconstruction by shutting down what are known as osteoclasts. Osteoclasts, like hungry termites, digest bone, and Tildren impedes their progress. More scientifically, Tildren is a class of substances known as bisphosphonates, which inhibit osteoclast action and the resorption of bone.