Efficacy and tolerability of lisdexamfetamine dimesylate (NRP-104) in children with attention-deficit/hyperactivity disorder: a phase III, multicenter, randomized, double-blind, forced-dose, parallel-group study.

Abstract

BACKGROUND:

Lisdexamfetamme dimesylate (LDX) is a therapeutically inactive amphetamine prodrug. It was developed with the goal of providing an extended duration of effect that is consistent throughout the day, with a reduced potential for abuse, overdose toxicity, and drug tampering. Following ingestion, the pharmacologically active d-amphetamine molecule is gradually released by rate-limited hydrolysis.

OBJECTIVES:

The aims of this study were to assess the efficacy and tolerability of LDX in school-aged children with attention-deficit/hyperactivity disorder (ADHD) treated in the community, and to characterize the duration of action of LDX compared with placebo.

METHODS:

This Phase III, multicenter, randomized, double-blind, forced-dose, parallel-group study was conducted at 40 centers across the United States. Male and female children aged 6 to 12 years with ADHD were randomly assigned to receive LDX 30, 50, or 70 mg with forced-dose titration, or placebo, PO QD for 4 weeks. Efficacy was assessed using the ADHD Rating Scale Version IV (ADHD-RS-IV), the Conners' Parent Rating Scale (CPR'), and the Clinical Global Impression of Improvement scale. Tolerability was assessed throughout the study.

RESULTS:

Of the 290 randomized patients (201 boys, 89 girls; mean [SD] age, 9 [1.8] years), 230 completed the trial (LDX 30 mg, n=56; LDX 50 mg, n=60; LDX 70 mg, n=60; and placebo, n=54). The most common reasons for study discontinuation (n=60) were lack of efficacy (LDX 30 mg, 1%; LDX 50 mg, 0%; LDX 70 mg, 1 %; and placebo, 17%) and adverse events (AEs) (LDX 30 mg, 9%; LDX 50 mg, 5%; LDX 70 mg, 14%; and placebo, 1%). Significant improvements in ADHD-RS-IV scores were seen with all doses of LDX compared with placebo (all, P<0.001), and in CPRS scores with all LDX doses versus placebo throughout the day (all, P<0.001 for all comparisons). Efficacy was observed by the first week of treatment, and improvements were observed throughout the day up to approximately 6 PM. The most frequently reported AEs among patients receiving LDX were typical of amphetamine products: decreased appetite (39% with active treatment vs 4% with placebo), insomnia (19% vs 3%), upper abdominal pain (12% vs 6%), headache (12% vs 10%), irritability (10% vs 0%), vomiting (9% vs 4%), weight decrease (9% vs 1%), and nausea (6% vs 3%); most were mild to moderate and occurred in the first week.

CONCLUSION:

In this population of children with ADHD, treatment once daily with the prodrug LDX at doses of 30 to 70 mg appeared to be effective and had a tolerability profile similar to those of currently marketed extended-release stimulants.

• Authors: Joseph Biederman, Suma Krishnan, Yuxin Zhang, James J McGough, Robert L Findling
• Journal: Clinical therapeutics (Clin Ther) Vol. 29 Issue 3 Pg. 450-63 (Mar 2007) ISSN: 0149-2918 [Print] United States
• PMID: 17577466 (Publication Type: Clinical Trial, Phase III, Journal Article, Multicenter Study, Randomized Controlled Trial, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't)

Chemical References

• Central Nervous System Stimulants
• Delayed-Action Preparations
• Lysine
• Lisdexamfetamine Dimesylate
• Dextroamphetamine

Topics

• Administration, Oral
• Attention Deficit Disorder with Hyperactivity (drug therapy)
• Central Nervous System Stimulants (administration & dosage, adverse effects, therapeutic use)
• Child
• Delayed-Action Preparations
• Dextroamphetamine (administration & dosage, adverse effects, therapeutic use)
• Diagnostic and Statistical Manual of Mental Disorders
• Double-Blind Method
• Female
• Humans
• Lisdexamfetamine Dimesylate
• Lysine
• Male
• Treatment Outcome