Precision Medicines’ Impact on Orphan Drug Designation

: The incentives provided under the Orphan Drug Act (ODA) have been credited for catalyzing the marketing approval of drugs for the treatment of rare diseases by the US Food and Drug Administration. Orphan drug designation, the granting of special status to drugs or biologics ("drugs") for the treatment of rare diseases, one of the ODA's key incentive programs, has seen major increases in volume over recent years. The new era of precision medicine and the development of therapies directed toward smaller "orphan" subsets of common diseases have been suggested as being a major driver. We evaluated the basis for orphan drug designations and orphan subsets in relation to the impact of precision medicines. We found that the increasing numbers of orphan drug designation determinations were not driven by precision medicines separating common diseases into orphan subsets and that orphan subsets overall also represented a relatively small proportion of designations.