Over the past two years, a working group within the FDA’s Center for Veterinary Medicine has explored potential changes to the approval process for combination drug medicated feeds.

According to the Animal Drug Availability Act (ADAA), the use of multiple new animal drugs in the same medicated feed requires animal drug sponsors to seek approval for each new animal drug used in the combination, and to seek separate approval for the combination drug itself.

The proposed changes fall within four main areas:

·         Labeling.

·         Phased review of ADAA combination new animal drugs.

·         Reducing time between the single type A medicated article approval and the combination drug approval.

·         Development of a Guidance for Industry to address content and process for approving ADAA combinations.

Labeling

The working group recommends that FDA/CVM publish the labels for all Type B and Type C medicated feeds, known as Blue Bird labels, on their Web page. Currently, Blue Bird labels available online consist mostly of recently approved labels. The group recommends FDA/CVM obtains or reallocates funds to permit the publication of all approved Blue Bird labels in a timely fashion and to continue publication of labels as new or revised labeling is approved in order to ensure continued success. The group also recommends that sponsors use the established name of the active pharmaceutical ingredient (API) used to prepare Type B and Type C medicated feeds on Blue Bird labels. If sponsors want to include the proprietary name of the Type A medicated article(s)) used to prepare the medicated feed, they suggest using footnotes. This, the group says, is consistent with CVM Guidance for Industry (GFI) #181, “Blue Bird Medicated Feed Labels.”

According to that document, Type A medicated articles are intended solely for use in the manufacture of another Type A medicated article or in the manufacture of Type B or Type C medicated feed. Type B medicated feed is manufactured by diluting a Type A medicated article or another Type B medicated feed. Type B medicated feed is intended solely for the manufacture of other Type B or Type C medicated feeds, and  cannot be fed as-is without being further diluted to Type C medicated feed. Type B medicated feed contains a substantial quantity of nutrients in an amount not less than 25% of the weight. Type C medicated feed is intended as the complete feed for the animal or may be fed 'top dressed' or offered 'free choice' in conjunction with other animal feed. It is manufactured by diluting a Type A medicated article, a Type B medicated feed, or another Type C medicated feed.

Phased review of ADAA combination new animal drugs

The working group proposes that sponsors pursuing approval of single new animal drugs for use in or on medicated feeds use an investigational new animal drug file (INAD file) and phased review processes for any medicated feed combinations that will contain the single new animal drug and other previously-approved new animal drugs.

Reducing time between the single type A medicated article approval and the combination drug approval

The working group proposes that CVM consider modifications to review time frames for certain types of submissions and applications for combination new animal drugs used in or on animal feeds. The group offers a list of specific proposals intended to shorten the time between approval of a single new animal drug and the ADAA combination new animal drug application to something less than the minimum 180-day time frame typical of the current process.

Development of a Guidance for Industry to address content and process for approving ADAA combinations

Rather than create a new guidance for industry (GFI) to address the content and approval process, the working group proposes that CVM examine whether language could be added to an existing guidance document, specifically GFI #132, “Administrative Applications and the Phased Review Process.” The working group proposes that the feasibility of adding language to a current GFI be examined once Congress has reauthorized the collection of animal drug user fees.

Read the full report from FDA/CVM.