Title page 1

Contents 3

Highlights 2

Letter 5

Background 10

FDA's Process for Approving New Animal Drugs 10

Incentives and Restrictions for Conditionally Approved Drugs 13

FDA Conditionally Approved 11 New Animal Drugs in Fiscal Years 2018 Through 2025 15

Regulatory Requirements for Demonstrating the Effectiveness of New Animal Drugs Limit the Use of Alternative Approaches 21

Changes to Conditional Approval Needed to Overcome Drug Development Challenges 28

Financial Incentives and Conditional Approval's 2018 Expansion Have Had a Limited Effect on New Animal Drug Development 28

Conditional Approval's Restrictions and Statutory 5-Year Limit Have Been Disincentives to New Animal Drug Development 30

Conclusions 35

Matter for Congressional Consideration 36

Recommendations for Executive Action 36

Agency Comments and Our Evaluation 36

Appendix I: Animal Drugs Conditionally Approved by the U.S. Food and Drug Administration, Fiscal Years 2004-2025 38

Appendix II: Examples of Research Funded by U.S. Food and Drug Administration's Animal and Veterinary Innovation Centers 51

Appendix III: Comments from the Department of Health and Human Services 57

Appendix IV: GAO Contact and Staff Acknowledgements 59

Tables 3

Table 1. Examples of Incentives to Support Drug Sponsors' Development of New Animal Drugs for Minor Uses and for Minor Species 14

Table 2. Restrictions on Conditionally Approved Animal Drugs 15

Table 3. New Animal Drugs Conditionally Approved by FDA from Fiscal Years 2018 Through 2025 18

Table 4. New Animal Drugs Conditionally Approved by FDA in First Quarter of Fiscal Year 2026 19

Table 5. New Animal Drugs the U.S. Food and Drug Administration Conditionally Approved Under the MUMS Act in Fiscal Years 2004 to 2018 38

Figures 4

Figure 1. Major Technical Sections of a U.S. Food and Drug Administration New Animal Drug Application and Examples of Drug Sponsor Actions 11

Figure 2. Number of New Animal Drug Approvals by Year and Type of FDA Approval, Fiscal Years 2018 Through 2025 16

Figure 3. Number of New Animal Drugs by Species or Groups of Species and Type of FDA Approval, Fiscal Years 2018 Through 2025 20

Figure 4. U.S. Food and Drug Administration (FDA) Guidance on Alternative Approaches for Conducting Adequate and Well-Controlled... 23

Figure 5. Example of an Animal Drug with an Approved and Conditionally Approved Indication 31

Figure 6. Example of a "Dual Labeled" Animal Drug with a U.S. Food and Drug Administration (FDA) Fully Approved and Conditionally... 32

Figure 7. Blackhead Disease Causes Liver and Digestive System Ulcers (Right) and Is 70 to 100 Percent Fatal in Affected Turkey Flocks 52

Figure 8. Each Year, Millions of Calves and Other Farm Animals Undergo Painful Procedures or Develop Painful Conditions Such as Lameness 54