Animal & Veterinary

Generic Animal Drugs: Approved or Unapproved?

The information on this page pertains to illegally marketed unapproved animal drugs, not to legally marketed indexed drugs.

Generic animal drugs are not the same as unapproved animal drugs. Unlike unapproved animal drugs, generic animal drugs are legally marketed in the United States and have been reviewed under FDA’s approval process.

What is “marketing exclusivity”?

“Marketing exclusivity” applies to brand name animal drugs. A drug company that gets a brand name animal drug approved by FDA is given marketing exclusivity. This means FDA cannot approve a generic copy for a specific number of years, usually three or five, from the date of approval of the brand name drug.

What are “exclusive marketing rights”?

“Exclusive marketing rights” apply to brand name animal drugs for minor species or minor uses in a major species (called “MUMS drugs”). A drug company that gets a brand name MUMS drug designated and then approved, or conditionally approved, by FDA is given exclusive marketing rights. This means FDA cannot approve a generic copy or another brand name version for seven years from the date of approval, or conditional approval, of the designated brand name MUMS drug.

After a drug company’s patent, marketing exclusivity, or exclusive marketing rights for an approved brand name animal drug expire, another drug company can start the approval process for a generic copy. Rather than the New Animal Drug Application process for a brand name animal drug, a generic animal drug goes through the Abbreviated New Animal Drug Application (ANADA) process. Called “abbreviated” because it’s shortened, the drug approval process for generic animal drugs was established in 1988 by the Generic Animal Drug and Patent Term Restoration Act (GADPTRA).

For a generic animal drug to be approved by FDA, the information in the ANADA must show that the generic copy is identical to the approved brand name animal drug in:

  • Active ingredient;
  • Strength;
  • Dosage form; and
  • Dosage regimen.

The information in the ANADA must also show that the generic copy is:

  • Consistently made from batch to batch; and
  • Bioequivalent to the approved brand name animal drug. This means that the generic drug is absorbed by and acts the same way in the animal’s body as the approved drug.

What does “dosage form” mean?

The dosage form is the drug’s physical form when it comes out of the manufacturing facility. There are several categories of dosage forms, including oral and injectable. A drug given by mouth is an oral dosage form. Tablets and capsules are two types of an oral dosage form. A drug that is injected under the skin, into muscle, or into a vein is an injectable dosage form. A solution is a common type of an injectable dosage form.

What does “dosage regimen” mean?

The dosage regimen includes:

  • How much of the drug to give (the dose);
  • How often to give it (the frequency);
  • How long to give it (the duration); and
  • How to give it (the route of administration). Various routes of administration include injecting the drug under the skin, into muscle, or into a vein; giving the drug by mouth; or applying the drug topically to the skin.

Also, the labeling for the generic copy must match the labeling for the approved brand name animal drug, although the generic copy may use a different trade name. For example, Heartgard® Tablets (Merial Ltd.) is the trade name of a brand name heartworm preventive. Iverhart™ Tablets (Virbac AH, Inc.) is the trade name of the generic copy.

A “generic name” is not the same as a “generic drug.” The term “generic name” refers to the drug’s established name, also called the active ingredient. In the heartworm preventive example above, the active ingredient in both Heartgard® Tablets and Iverhart™ Tablets is ivermectin. Ivermectin is the generic (established) name of the drug, but Iverhart™ Tablets is the generic drug.

Because unapproved animal drugs have not gone through FDA’s approval process, there’s no way to know if these drugs are safe and effective. Generic animal drugs, on the other hand, are reviewed by FDA and have met FDA’s strict standards for safety and effectiveness. Generic copies are legal alternatives to approved brand name animal drugs.

Page Last Updated: 07/09/2014
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