title: Predictive value of the efficacy of glaucoma medications in regulatory trials: Phase I-III to post-marketing studies.
abstract: OBJECTIVE
  To determine the predictive value of early Phase trials (I-II) for the ocular hypotensive efficacy observed in Phases III and IV.
  
  
  METHODS
  A review of published literature.
  
  
  METHODS
  This study evaluated 12 medicines in 65 articles in the literature with at least two phases available.
  
  
  RESULTS
  For medicines with Phase I results available (n=3), the average reduction in intraocular pressure (IOP) from untreated baseline was 16%, 26% for Phase II, 26% for Phase III, and 24% for Phase IV. For medicines with Phase II results available (n=6), the average reduction in IOP was 23%, 24% for Phase III, and 23% for Phase IV. For medicines with Phase III results available (n=11), the average reduction in IOP was 25% and 24% for Phase IV.
  
  
  CONCLUSIONS
  This study indicates that early phase trials usually approximated the results of later regulatory studies and post-commercialization trials.
authors.affiliation: PRN Pharmaceutical Research Network, LLC, Dallas, TX, USA. info@prnorb.com
authors.forename: W C
authors.initials: WC
authors.lastname: Stewart
authors.forename: J N
authors.initials: JN
authors.lastname: Jenkins
mesh_terms: D000959:Antihypertensive Agents / Q000627:therapeutic use*; D002986:Clinical Trials as Topic; D005901:Glaucoma / Q000188:drug therapy* / Q000503:physiopathology; D006801:Humans; D007429:Intraocular Pressure / Q000187:drug effects; D016896:Treatment Outcome
chemical_list: D000959:Antihypertensive Agents