title: Does market exclusivity hinder the development of Follow-on Orphan Medicinal Products in Europe?
abstract: BACKGROUND
  We determined whether the market exclusivity incentive of the European Orphan Drug Regulation results in a market monopoly or that absence of another Orphan Medicinal Product (OMP) for the same rare disorder, a so-called follow-on OMP, is a matter of time or market size. In the interest of rare disorder patients better understanding of the effect of the market exclusivity incentive on follow-on OMP development is warranted.
  
  
  METHODS
  First, the impact of various market-, product- and disease-related characteristics on follow-on OMP development in the EU was determined by comparing rare disorders with an approved OMP and at least one follow-on OMP (N = 26), with rare disorders with an approved OMP and no follow-on OMP (N = 18). Next, we determined whether manufacturers continued development of a follow-on OMP upon approval of the first OMP for the intended rare disorder. Since in the EU significant benefit of an OMP has to be established, we determined for each follow-on OMP for which development was continued on what grounds significant benefit was assumed by the sponsor. Data were collected from the public domain only.
  
  
  RESULTS
  The likelihood of a rare disorder with an approved OMP to obtain at least one follow-on OMP development was strongly associated with disease prevalence, turnover of the first OMP, disease class, disease-specific scientific output and age of onset. Out of a total of 120 follow-on OMPs only one follow-on OMP could be identified for which development was discontinued upon approval of the first OMP for the same rare disorder. Only a substantial level of discontinuation of follow-on OMP development would have indicated the existence of a market monopoly. Moreover, sponsors that continued development of a follow-on OMP predominantly assumed that their product had an improved efficacy compared to the first approved OMP.
  
  
  CONCLUSIONS
  This study provides evidence that absence of follow-on OMP development is a matter of time or market size, rather than that the market exclusivity incentive of the European Orphan Drug Regulation creates a market monopoly.
authors: NIVEL, Netherlands Institute for Health Services Research, PO Box 1568, 3500 BN Utrecht, The Netherlands. a.brabers@nivel.nl
authors: Anne E M
authors: AE
authors: Brabers
authors: Ellen H M
authors: EH
authors: Moors
authors: Sonja
authors: S
authors: van Weely
authors: Remco L A
authors: RL
authors: de Vrueh
mesh_terms: D017277:Drug Approval / Q000331:legislation & jurisprudence / Q000706:statistics & numerical data*; D015195:Drug Design; D004345:Drug Industry / Q000191:economics* / Q000331:legislation & jurisprudence / Q000639:trends; D005060:Europe; D006801:Humans; D009965:Orphan Drug Production / Q000191:economics* / Q000331:legislation & jurisprudence* / Q000379:methods / Q000706:statistics & numerical data; D015995:Prevalence; D035583:Rare Diseases / Q000188:drug therapy* / Q000453:epidemiology