Comparison of therapy augmentation and deviation rates from the recommended once-daily dosing regimen between LDX and commonly prescribed long-acting stimulants for the treatment of ADHD in youth and adults.

OBJECTIVE

To compare therapy augmentation and deviation rates from the recommended once-daily dosing regimen in Attention Deficit Hyperactivity Disorder (ADHD) patients initiated on lisdexamfetamine (LDX) vs other once-daily Food and Drug Administration (FDA) approved stimulants.

METHODS

ADHD patients initiated on a long-acting ADHD stimulant medication (index medication) in/after 2007 were selected from a large U.S. administrative claims database. Patients were required to be persistent for ≥90 days and continuously enrolled in their healthcare plan for ≥12 months following treatment initiation date. Based on age and previous treatment status, patients were classified into treatment-naïve children and adolescents (6-17 years old), previously treated children and adolescents, treatment-naïve adults (≥18 years old), and previously treated adults. Furthermore, patients were classified into four mutually exclusive treatment groups, based on index medication: lisdexamfetamine (LDX), osmotic release methylphenidate hydrochloride long-acting (OROS MPH), other methylphenidate/dexmethylphenidate long-acting (MPH LA), and amphetamine/dextroamphetamine long-acting (AMPH LA). The average daily consumption was measured as the quantity of index medication supplied in the 12-month study period divided by the total number of days of supply. Therapy augmentation was defined as the use of another ADHD medication concomitantly with the index medication for ≥28 consecutive days. Therapy augmentation and deviation rates from the recommended once-daily dosing regimen were compared between treatment groups using multivariate logistic regression models.

RESULTS

Compared to the other treatment groups, LDX patients were less likely to augment with another ADHD medication (range odds ratios [OR]; 1.28-3.30) and to deviate from the recommended once-daily dosing regimen (range OR; 1.73-4.55), except for previously treated adult patients, where therapy augmentation differences were not statistically significant when compared to OROS MPH and MPH LA patients.

LIMITATION

This study did not control for ADHD severity.

CONCLUSION

Overall, compared to LDX-treated patients, patients initiated on other ADHD medications were equally or more likely to have a therapy augmentation and more likely to deviate from the recommended once-daily dosing regimen.