FDA Issues Draft Guidance on Expanded Conditional Approval for Animal Drugs

October 9, 2019By Riëtte van Laack

On September 30, 2019, FDA announced the availability of a draft guidance for Industry, titled “Eligibility Criteria for Expanded Conditional Approval of New Animal Drugs.”  This guidance addresses a special pathway for approval of animal drugs that address serious or life-threatening diseases or conditions, or an unmet animal or human health need, and for which demonstrating effectiveness would require complex or particularly difficult study or studies.  This new pathway is the result of an amendment in 2018.

Following the enactment of the 2004 Minor Use and Minor Species (MUMS) Animal Health Act, FDA established a “conditional approval” pathway to allow the development of animal drugs in commercially limited markets.  The conditional approval pathway allowed the marketing of animal drugs for minor species or for minor uses for major species after demonstrating that the animal drug is safe and that there is a reasonable expectation of effectiveness; upon receiving conditional approval, manufacturers may market the drug for up to five years while collecting data to demonstrate effectiveness.

In August 2018, the Animal Drug User Fee Act (ADUFA IV) amended the FDC Act to expand the conditional approval pathway beyond MUMS to include new animal drugs for a serious or life-threatening disease or condition or drugs intended to address an unmet animal or human health need, and for which proof of effectiveness would require a particularly difficult study or studies.  ADUFA directed FDA to issue guidance to identify the relevant terms by September 30, 2019.

A serious or life-threatening disease or condition

FDA identifies three categories of serious or life-threatening diseases or conditions: 1) those associated with morbidity that has a substantial impact on the day‐to‐day functioning or is associated with mortality in the target animal; 2) zoonotic diseases that present a risk of serious or life-threatening disease or condition to humans; and 3) diseases or conditions in food-producing animals with a risk of disrupting regional or national food supply.

“Unmet animal or human health need”

FDA defines an unmet need as a disease or condition for which the treatment, control, or prevention is not adequately addressed by available therapy or, if a therapy exists, the new drug is expected to provide a meaningful advantage.  “Available therapy” means a product that is FDA approved, licensed by the USDA as a veterinary biologic, or registered EPA, and is currently being marketed in the U.S. for the same intended use in the same species proposed for the new animal drug product for which expanded conditional approval is sought.

A product can provide a “meaningful advantage” over a currently existing therapy in several ways, e.g., by providing clinically relevant improved effectiveness or beneficial effect; providing effectiveness in animals that cannot tolerate the currently available therapy; and providing similar effectiveness but improved safety.

Complex or difficult study or studies

FDA will determine whether a study is complex or particularly difficult on a case-by-case basis.  The guidance provides factors the Agency will consider when making its determination.

In addition to discussing the meaning of the terms, FDA reminds interested parties that the law specifies that the pathway of expanded conditional approval is not available for antimicrobial drugs.  Also, of interest is FDA’s clarification regarding the exclusion of transgenic animals.  As FDA notes, the law specifies that conditional approval pathway is not available for transgenic animal defined as “an animal whose genome contains a nucleotide sequence that has been intentionally modified in vitro.” FDA notes that intentional genomic alterations such as gene deletions do not meet the definition of transgenic and such products might be eligible for conditional approval (provided they meet the other conditions).

To be considered, comments must be submitted to docket FDA-2019-D-3361 on www.regulations.gov beginning no later than January 28, 2020.