title: Randomized clinical study of a histamine H3 receptor antagonist for the treatment of adults with attention-deficit hyperactivity disorder.
abstract: BACKGROUND
  Psychostimulants, including methylphenidate and amphetamine preparations, are commonly prescribed for the treatment of attention-deficit hyperactivity disorder (ADHD) in children and adults. Histamine H3 receptors reside on non-histamine neurons and regulate other neurotransmitters (e.g. acetylcholine, noradrenaline [norepinephrine]) suggesting that H3 antagonists have the potential to improve attention and impulsivity. Research indicates that H3 receptor antagonists due to their novel mechanism of action may have a unique treatment effect offering an important alternative for the treatment of ADHD. Bavisant (JNJ-31001074) is a highly selective, orally active antagonist of the human H3 receptor with a novel mechanism of action, involving wakefulness and cognition, with potential as a treatment for ADHD.
  
  
  OBJECTIVE
  The objective of this study was to evaluate the efficacy, safety and tolerability of three dosages of bavisant compared with placebo in adults with ADHD.
  
  
  METHODS
  This randomized, double-blind, placebo- and active-controlled, parallel-group, multicentre study evaluated three dosages of bavisant (1 mg/day, 3 mg/day or 10 mg/day) and two active controls in adults with ADHD. The study consisted of a screening phase of up to 14 days, a 42-day double-blind treatment phase and a 7-day post-treatment follow-up phase. Efficacy and safety assessments were performed.
  
  
  METHODS
  The study was conducted at 37 study centres in the US from April 2009 through January 2010.
  
  
  METHODS
  Men and women aged 18-55 years with an established diagnosis of ADHD as confirmed by clinician and self-report diagnostic measures were enrolled.
  
  
  METHODS
  Participants were randomly assigned equally to one of six treatment groups: placebo, bavisant 1 mg/day, 3 mg/day or 10 mg/day, atomoxetine hydrochloride 80 mg/day or osmotic-release oral system (OROS) methylphenidate hydrochloride 54 mg/day.
  
  
  METHODS
  The primary efficacy endpoint was the change in the Attention Deficit Hyperactivity Disorder Rating Scale, Version IV (ADHD-RS-IV) total score from baseline (day 1) to the end of the treatment phase (day 42), and included all randomized participants who received one or more doses of study drug and had baseline and one or more post-baseline assessments (intent-to-treat [ITT] population). Safety assessments included treatment-emergent adverse events (TEAEs), laboratory tests and ECG readings.
  
  
  RESULTS
  430 participants were randomized, 424 received one or more doses of study medication and 335 (78%) of those randomized completed the study. Study participants had a mean age of 33.9 years and were predominantly White men. Mean treatment duration ranged from 31.4 to 38.8 days across groups. Mean change from baseline in the total ADHD-RS-IV score at day 42 (primary efficacy endpoint) was -8.8 in the placebo group versus -9.3, -11.2 and -12.2 in the bavisant 1 mg/day, 3 mg/day and 10 mg/day groups, respectively; the change in the 10 mg/day group was not statistically superior to placebo (p=0.161), and hence statistical comparisons of the 1 mg/day and 3 mg/day groups with placebo based on a step-down closed testing procedure were not performed. Mean change from baseline in the total ADHD-RS-IV score at day 42 was superior to placebo in the atomoxetine (-15.3) and OROS methylphenidate (-15.7) groups (p<0.005). Secondary efficacy assessments demonstrated a similar pattern with a non-significant trend towards improvement in the bavisant groups. The two lower dosages showed a good tolerability profile, but the higher dosage of bavisant was less well tolerated, as evidenced by the incidence of total TEAEs (61.8%, 82.4%, 89.0%), and discontinuations due to TEAEs (4.4%, 7.4%, 19.2%) in the bavisant 1 mg/day, 3 mg/day and 10 mg/day groups, respectively, compared with 58.9% and 2.7%, respectively on placebo. In the atomoxetine and OROS methylphenidate groups, the incidence of total TEAEs was 83.8% and 82.4% and discontinuations due to TEAEs was 10.8% and 8.8%, respectively.
  
  
  CONCLUSIONS
  Bavisant, a highly selective, wakefulness-promoting H3 antagonist, did not display significant clinical effectiveness in the treatment of adults with ADHD.
  
  
  BACKGROUND
  NCT00880217.
authors.affiliation: Duke University Medical Center, NC, USA.
authors.forename: Richard H
authors.initials: RH
authors.lastname: Weisler
authors.forename: Gahan J
authors.initials: GJ
authors.lastname: Pandina
authors.forename: Ella J
authors.initials: EJ
authors.lastname: Daly
authors.forename: Kimberly
authors.initials: K
authors.lastname: Cooper
authors.forename: Cristiana
authors.initials: C
authors.lastname: Gassmann-Mayer
mesh_terms: D000284:Administration, Oral; D000293:Adolescent; D018759:Adrenergic Uptake Inhibitors / Q000627:therapeutic use; D000328:Adult; D000069445:Atomoxetine Hydrochloride; D001289:Attention Deficit Disorder with Hyperactivity / Q000188:drug therapy*; D001549:Benzamides / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D000697:Central Nervous System Stimulants / Q000627:therapeutic use; D003692:Delayed-Action Preparations; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D005260:Female; D005500:Follow-Up Studies; D054828:Histamine H3 Antagonists / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D006801:Humans; D008297:Male; D008774:Methylphenidate / Q000627:therapeutic use; D008875:Middle Aged; D010879:Piperazines / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D011437:Propylamines / Q000627:therapeutic use; D016896:Treatment Outcome; D014851:Wakefulness / Q000187:drug effects; D055815:Young Adult
chemical_list: D018759:Adrenergic Uptake Inhibitors; D001549:Benzamides; D000697:Central Nervous System Stimulants; D003692:Delayed-Action Preparations; D054828:Histamine H3 Antagonists; D010879:Piperazines; D011437:Propylamines; D008774:Methylphenidate; D000069445:Atomoxetine Hydrochloride; C574166:bavisant