title: Development of a new once-a-day formulation of methylphenidate for the treatment of attention-deficit/hyperactivity disorder: proof-of-concept and proof-of-product studies.
abstract: BACKGROUND
  The duration of action of the immediate-release formulation of methylphenidate hydrochloride is short (3 to 4 hours), and 3 times daily dosing is thought to maximize effectiveness across a 12-hour day. The initial sustained-release formulations of methylphenidate had reduced efficacy compared with immediate-release methylphenidate and were not well accepted. Tachyphylaxis was hypothesized to account for the reduced effects, and an ascending drug delivery pattern was proposed to overcome this acute tolerance.
  
  
  METHODS
  Children with attention-deficit/hyperactivity disorder were evaluated in a laboratory school to characterize onset and duration of the effect of a variety of methylphenidate regimens. In a proof-of-concept study, an experimental ascending profile was established by an initial bolus followed by small increasing doses of immediate-release methylphenidate in capsules administered every 30 minutes for 8 hours. Two proof-of-product studies of a new oral once-a-day formulation to deliver methylphenidate by an osmotic pump process based on OROS (ALZA Corp, Mountain View, Calif) technology (hereafter referred to "OROS-methylphenidate") were conducted: a pharmacokinetic study and a pharmacodynamic study.
  
  
  RESULTS
  The experimental ascending profile matched the effect of the standard regimen of methylphenidate, 3 times daily. In the pharmacokinetic study, OROS-methylphenidate treatment produced a rapid rise followed by increasing plasma concentrations that peaked 7 to 9 hours after administration. In the pharmacodynamic study, OROS-methylphenidate treatment matched the 3 times daily dosing of methylphenidate for onset and duration of efficacy.
  
  
  CONCLUSIONS
  These studies demonstrate the translation of a basic science finding (acute tolerance to clinical doses of methylphenidate) into clinical application (the selection of a new drug delivery pattern for methylphenidate). This approach produced a new product (OROS-methylphenidate or Concerta), which proved to have the predicted rapid onset (with 1-2 hours) and long duration of efficacy (10-12 hours) after a single administration in the morning.
authors.affiliation: University of California, Irvine, Department of Pediatrics, Child Development Center, CA, USA.
authors.forename: James
authors.initials: J
authors.lastname: Swanson
authors.forename: Suneel
authors.initials: S
authors.lastname: Gupta
authors.forename: Andrew
authors.initials: A
authors.lastname: Lam
authors.forename: Ira
authors.initials: I
authors.lastname: Shoulson
authors.forename: Marc
authors.initials: M
authors.lastname: Lerner
authors.forename: Nishit
authors.initials: N
authors.lastname: Modi
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Lindemulder
authors.forename: Sharon
authors.initials: S
authors.lastname: Wigal
mesh_terms: D000284:Administration, Oral; D000293:Adolescent; D001289:Attention Deficit Disorder with Hyperactivity / Q000188:drug therapy*; D002214:Capsules / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000627:therapeutic use; D000697:Central Nervous System Stimulants / Q000008:administration & dosage* / Q000493:pharmacokinetics / Q000627:therapeutic use; D002648:Child; D002985:Clinical Protocols; D015331:Cohort Studies; D018592:Cross-Over Studies; D003692:Delayed-Action Preparations; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D016503:Drug Delivery Systems; D006801:Humans; D007408:Intestinal Absorption; D008774:Methylphenidate / Q000008:administration & dosage* / Q000493:pharmacokinetics / Q000627:therapeutic use; D010919:Placebos; D013618:Tachyphylaxis / Q000502:physiology; D016896:Treatment Outcome
chemical_list: D002214:Capsules; D000697:Central Nervous System Stimulants; D003692:Delayed-Action Preparations; D010919:Placebos; D008774:Methylphenidate