CHICAGO — Atomoxetine for the treatment of attention-deficit/hyperactivity disorder is generally safe and well tolerated in children and adolescents for up to more than 4 years of treatment, results of two open-label extension studies show.
Dr. Craig L. Donnelly reported the findings, which were based on 714 children and adolescents who had been treated for more than 3 years and 508 who had been treated for more than 4 years.
No new or unexpected safety or tolerability concerns emerged during more than 4 years of treatment, said Dr. Donnelly, director of child and adolescent psychiatry at Dartmouth-Hitchcock Medical Center, Lebanon, N.H.
The study will be published in the February issue of the Journal of the American Academy of Child and Adolescent Psychiatry.
Previous studies have found treatment of ADHD with atomoxetine to be safe and well tolerated by children and adolescents for 2 years (J. Am. Acad. Child Adolesc. Psychiatry 2006;45:919–27; J. Pediatr. 2006;149:112–9). The new studies were conducted to determine the safety and tolerability of atomoxetine (Strattera) in children and adolescents who had received treatment for more than 3 or 4 years.
As with previous safety and tolerability reports, “patients experienced significant changes in vitals and growth compared with their baseline; however, changes were within the range of normal development,” Dr. Donnelly wrote in a poster at the annual meeting of the American Academy of Child and Adolescent Psychiatry. No clinically significant abnormalities were found in height, weight, blood pressure, mean laboratory values, or electrocardiograms.
The participants (aged 6–17 years; mean age at baseline 10.5 years) came from 13 double-blind, placebo-controlled trials and 3 open-label extension studies. They met DSM-IV diagnostic criteria for ADHD at entry into their initial studies. Researchers measured vital signs, electrocardiogram, weight, growth, hepatic function, treatment-emergent adverse advents, and reasons for discontinuation, and compared changes from baseline to end point.
The most common treatment-emergent adverse event was headache, reported by 53.9% of patients who had been taking the medication for more than 3 years and 53.7% of patients who had been taking the medication for more than 4 years. Other common treatment-emergent adverse events included nasopharyngitis (37.8%, 37.6%), vomiting (37.4%, 37.8%), cough (33.6%, 37.0%), upper abdominal pain (32.8%, 33.9%), pharyngolaryngeal pain (32.1%, 34.8%), pyrexia (31.8%, 33.3%), and upper respiratory tract infection (30.8, 32.1).
Fewer than 2% of patients had potentially clinically significant changes in hepatic function test results; two patients discontinued treatment for this reason.
Suicidal ideation and behavior occurred in 1.5% and 0.4% of patients, respectively; no suicides occurred during these studies. Transient aggressive/hostile behavior occurred in less than 6% of patients.
Of the 1,553 patients in the long-term, open-label study, 839 (54%) discontinued treatment before 3 years, citing adverse event (8.5%), perceived lack of efficacy (26.2%), patient decision (49.3%), physician decision (4.5%), satisfactory response (1.9%), and other (9.5%).
The study was sponsored by Eli Lilly & Co. Dr. Donnelly is as a consultant and a member of the speakers bureau for Eli Lilly. He has conducted other research funded by the company.