Presentation (CTI)

OBJECTIVES: To investigate the feasibility of using imputed body weight to evaluate whether real-world methylphenidate extended-release (MTP-ER) dosing in youths with attention deficit-hyperactivity disorder (ADHD) achieves effective therapeutic concentrations.
METHODS: The IQVIA PharMetrics® Plus for Academics database was used to create the study cohort of youths aged 5-17 years with ADHD who had an MTP-ER prescription in 2020. Daily MTP-ER dosage was calculated for each prescription dispensed on the date of the first MTP-ER prescription (i.e., index date). A youth’s body weight was imputed from the age- and sex-specific normal distributions derived from the CDC growth chart. We used a published pharmacokinetic model for MTP-ER to estimate therapeutic concentrations based on imputed body weight and assuming 16% bioavailability.
RESULTS: The study cohort included 12,011 youths, of whom 68.21% were male, 31.57% aged 3-9 years, 40.17% aged 10-13 years, and 28.26% aged 14-17 years. Daily MTP-ER dosage ranged from 8.6mg to 108mg, with 99.18% of youths receiving ≤ 60mg/day. The imputed mean body weights were 25.17kg (95% CI: 15.09, 35.25) for youths aged 5-9 years, 39.16kg (95% CI: 20.80, 57.52) for youths aged 10-13 years, and 55.58kg (95% CI: 34.05, 77.10) for youths aged 14-17 years. Daily dosages below 20mg were estimated to be below an effective therapeutic concentration for MTP-ER. Older youth had the largest proportion of youth with MTP-ER concentrations below the effective therapeutic concentration.
CONCLUSIONS: Using pharmacokinetic models in real-world claims data enables investigation of dose-exposure relationships, which can inform health outcomes in pediatric populations with ADHD.