The Food and Drug Administration's Center for Veterinary Medicine announced May 11 that it recognizes veterinarians and horse owners are concerned over the voluntary withdrawal of pergolide from the human drug market.
Pergolide is often used to treat horses with pituitary pars intermedia dysfunction, also known as equine Cushing's disease. Veterinarians have prescribed pergolide under the provisions of the Animal Medicinal Drug Use Clarification Act, which allows practitioners to prescribe approved human drugs for extralabel use in animals.
But the FDA announced in March that the drug was to be withdrawn from the human market because of the risk of serious damage to patients' heart valves (see JAVMA, June 1, 2007).
The FDA is working with the sponsors of the approved products and all other interested parties to ensure that pergolide remains available to treat horses with PPID until a new animal drug application is approved for that use. According to the FDA statement: "This includes trying to make the approved product available through veterinary distribution channels and exercising enforcement discretion as appropriate over the pharmacy compounding of pergolide." Bulk substance used for pharmacy compounding should be labeled for "animal use only." All pharmacy compounding must be done under a valid veterinary prescription to treat an affected horse.
Although the sponsor has stopped marketing pergolide for human use, the FDA-CVM will work with sponsors who are interested in seeking approval of a new animal drug application for the use of pergolide to treat horses with PPID.
The American Association of Equine Practitioners has worked closely with the CVM to educate and emphasize the importance of pergolide to equine practitioners and their clients. In a letter to member veterinarians on May 11, the AAEP stated: "The FDA recognizes the importance of these drugs and because of a healthy alliance with the AAEP, the agency learned of the situation quickly and made its decision to apply regulatory discretion to the compounding of pergolide from bulk sources. Compounding pharmacies should not experience any shortage of the bulk product."
For more information, contact Dr. Christopher Melluso at the FDA by e-mail, Christopher [dot] Mellusofda [dot] hhs [dot] gov, or by phone, (240) 276-9065.