The equine tendon medication Bapten has been discontinued by its manufacturer, PR Pharmaceuticals, because of a lack of demand. The expense and length of treatment involved with Bapten therapy kept it from becoming popular, according to Keri Nightingale, the company’s marketing manager for Bapten.

“It requires a bit of commitment on the horse owner’s part,” she said. “There is a fairly strict exercise regimen in which the amount of work is increased slowly for about a year. There also is the cost of multiple veterinary visits.”

Known scientifically as beta-aminoproprionitrile fumarate, Bapten was approved by the Food and Drug Administration (FDA) in 1998. Research showed that the drug promoted a more natural alignment of tendon fibers during the healing process. Boehringer-Ingelheim was the original distributor and manufacturer. But soon after the product became available commercially, there were reports of excessive swelling in some tendons following use of the drug. Boehringer-Ingelheim voluntarily took Bapten off the market late in 1998 and investigated the problem, which was related to dose amount and the size of the tendon lesion being treated. Sales of Bapten resumed in March of 1999, but Boehringer-Ingelheim dropped the product later that year, citing financial reasons.

PR Pharmaceuticals, based in Fort Collins, Colo., acquired the  rights for Bapten and began selling it in 2000, but the company had difficulty overcoming the drug’s bad publicity. “Bapten is a fantastic product,” Nightingale said. “But any time a drug is pulled off the market, it puts a message in minds that something is wrong.”