Evaluating The Impact Of The Orphan Drug Act's Seven-Year Market Exclusivity Period

Health Aff (Millwood). 2018 May;37(5):732-737. doi: 10.1377/hlthaff.2017.1179.


For thirty-five years the Orphan Drug Act of 1983 has provided incentives for pharmaceutical manufacturers to develop drugs to treat rare diseases-conditions that affect fewer than 200,000 people in the US. One key statutory incentive is an exclusive seven-year marketing right for the rare disease indication, which has been heralded as driving a dramatic increase in the number of rare disease treatments. However, most new drugs are also protected by patents. In this study we assessed all new small-molecule drugs approved in the period 1985-2014 that had at least one indication for an orphan-designated disease as of January 1, 2017. We found that orphan drug exclusivity outlasted the last expiring patent in 33 percent of cases overall, and in a smaller percentage of cases for each successive ten-year drug cohort: from 50 percent for drugs approved in 1985-94 to 35 percent for those approved in 1995-2004 and 18 percent for those approved in 2005-14. The Orphan Drug Act's market exclusivity incentive has played an increasingly smaller role in protecting rare disease drugs from competition, while rare disease drugs have substantially increased as a fraction of all new drug approvals.

Keywords: Pharmaceuticals.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cohort Studies
  • Drug Approval / legislation & jurisprudence*
  • Drug Industry / legislation & jurisprudence*
  • Female
  • Humans
  • Male
  • Marketing
  • Orphan Drug Production / legislation & jurisprudence*
  • Orphan Drug Production / statistics & numerical data
  • Quality Control
  • Rare Diseases / drug therapy*
  • Retrospective Studies
  • Time Factors
  • United States
  • United States Food and Drug Administration*