Under the Minor Use and Minor Species Animal Health Act, which was passed in 2004, the FDA has options for “conditional approvals” of some drugs. These conditional approvals can come into play to help drug sponsors and veterinarians provide treatments for minor species, or for small numbers of major species in the case of uncommon diseases. FDA recently launched an online resource center to serve as a reference on conditional approvals.

Major species, according to the USDA, include horses, dogs, cats, cattle, pigs, turkeys, and chickens. Other animals are considered minor species for the purpose of conditional drug approvals. As mentioned, conditional approvals for drugs used in major species would occur when the number of animals needing the treatment is relatively small, such as with an uncommon disease or isolated outbreak. In the case of cattle, that number is defined as 310,000 head.

The FDA resource center offers answers to common questions regarding conditional approvals and the use of these drugs, including:

  • What animal drugs are eligible for conditional approval?
  • What's the difference between conditional approval and full approval?
  • What does FDA's conditional approval allow a drug company to do?
  • What happens if the drug company can't complete the effectiveness requirements before the conditional approval expires?
  • How does conditional approval benefit you and your patients?
  • Can you use conditionally approved animal drugs in ways that are not described on the label (extra-label use)?
  • Should you report an adverse reaction related to a conditionally approved animal drug?
  • What are the three animal drugs that FDA has conditionally approved and for what uses?
  • What does the "CA1" mean after each drug name?

Find the full set of resources on the FDA veterinary website.