Pharmacokinetics and Pharmacodynamics of Topiramate for Weight Loss in Youth: PHARMATOP — PHARMATOP  

Obesity, Childhood Clinical Trial

Official title: Pharmacokinetics and Pharmacodynamics of Topiramate for Weight Loss in Youth: PHARMATOP

Status Recruiting

Clinical Trial Summary

Pediatric severe obesity is the fastest growing obesity category in the United States, and anti-obesity pharmacotherapies are promising adjuncts to lifestyle modification (LSM) for the treatment of this disease. While anti-obesity pharmacotherapies have overall been associated with mean weight loss, there is substantial variability in their individual-level effectiveness. While some patients lose a significant amount of weight with anti-obesity pharmacotherapies, others lose little or even gain weight.

Due to this well-recognized variability in individual-level response, the National Institutes of Health (NIH) has recognized the importance of using precision medicine approaches in order to optimize treatments for pediatric severe obesity. Pharmacometrics, which uses mathematical models to study medication dose-exposure (i.e. blood drug concentrations)-response relationships, is an emerging science that can help determine optimal dosing regimens based upon patient-specific characteristics. Pharmacometrics quantitates the interplay between pharmacokinetics (PK; drug dose-exposure associations) and pharmacodynamics (PD; drug exposure-response associations). Population PK (popPK), a type of PK, can be used to quantitate variability in drug exposure among individuals in order to help inform recommendations on therapeutic individualization (e.g. through tailored dosing). In this study, investigators will use popPK/PD modeling to characterize associations between anti-obesity pharmacotherapy dose, exposure, and changes in weight and weight-related outcomes in youth with severe obesity.

This study will focus on topiramate because this medication is commonly prescribed for weight loss in youth with severe obesity and has been associated with highly variable individual-level effectiveness.

Clinical Trial Description

The weight loss achieved with topiramate occurs through several purported mechanisms including reductions in appetite, food cravings, and binge eating, and adverse alterations in taste for carbonated beverages. It is hypothesized that some of the individual-level effectiveness of this medication on weight loss response is secondary to patient-specific differences in these factors. In a 3.5-month pragmatic-based prospective cohort study (n=65), the investigators will develop a popPK model using sparse sampling by drawing a series of topiramate concentration measures over time in order to begin determining patient-specific factors that contribute to topiramate exposure variability. The investigators will also identity associations between topiramate exposure, changes in eating behaviors, and weight loss outcomes through PD models using regression techniques. It is hypothesized that patient-specific characteristics (i.e. age, body mass index (BMI), and sex) will explain some variability in topiramate exposure in youth, and that higher topiramate exposure will be associated with greater improvements in weight loss response and eating behaviors among youth prescribed this medicine for the treatment of pediatric severe obesity. ;

Related Conditions & MeSH terms

• Obesity, Childhood
• Pediatric Obesity
• Weight Loss

• NCT number: NCT04986631
• Study type: Interventional
• Source: University of Minnesota
• Contact: Eric Bomberg, MD
• Phone: (612) 301-2563
• Email: bombe002@umn.edu
• Status: Recruiting
• Phase: Early Phase 1
• Start date: April 4, 2022
• Completion date: November 2025