title: Challenges in analgesic drug development.
authors.affiliation: Clinical Neuroscience, Merck Research Laboratories, North Wales, Pennsylvania, USA. david_hewitt@merck.com
authors.forename: D J
authors.initials: DJ
authors.lastname: Hewitt
authors.forename: R J
authors.initials: RJ
authors.lastname: Hargreaves
authors.forename: S P
authors.initials: SP
authors.lastname: Curtis
authors.forename: D
authors.initials: D
authors.lastname: Michelson
mesh_terms: D000700:Analgesics / Q000494:pharmacology* / Q000627:therapeutic use; D000818:Animals; D035843:Biomedical Research / Q000379:methods*; D002986:Clinical Trials as Topic / Q000379:methods*; D004305:Dose-Response Relationship, Drug; D055808:Drug Discovery; D006801:Humans; D008954:Models, Biological; D012107:Research Design
chemical_list: D000700:Analgesics