Abstract
The U.S. Food and Drug Administration and European Commission have developed successful orphan drug legislation to promote the research, development, and marketing approval of drugs to treat rare diseases. Central to these regulations are the concepts of structural similarity and clinical superiority/significant benefit to achieve orphan drug exclusivity. However, differences in health authority expectations remain regarding the qualification for an orphan drug designation, defining structural similarity, and demonstrating clinical superiority/significant benefit. These differences can create sponsor company uncertainty regarding the approvability of products (e.g., blocking risk by an existing orphan product) and divergent orphan drug decisions among health authorities. A comprehensive assessment of current regulations, case studies in exclusivities, and recommendations for improvement are presented.
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06 December 2022
A Correction to this paper has been published: https://doi.org/10.1007/s43441-022-00487-w
References
The word “drug” refers to both small molecules, biologics, and macromolecules. Please see Tables 1–2 for both US and EU definition of molecules.
A non-rare disease or condition occurring in >200,000 persons may also be designated as an orphan drug if an orphan subset of the patient population can be justified based upon drug toxicity, mechanism of action, or previous clinical experience with the drug.
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The authors additionally wish to thank Sebastian Roehrich, Amr Abdallah, Anja Markert, Jane Møll Pedersen, Karen Schumann, and Michael Søberg Christensen for the careful review of this manuscript.
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Roberts, S.W., Elvang, T.L.B., Syed, L. et al. Regulatory Considerations Toward Orphan Drug Designation and Orphan Drug Exclusivity in the United States and European Union: Structural Similarity, Clinical Superiority/Significant Benefit, and Case Studies. Ther Innov Regul Sci 57, 386–395 (2023). https://doi.org/10.1007/s43441-022-00477-y
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DOI: https://doi.org/10.1007/s43441-022-00477-y