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Open Access 18-12-2024 | Rett Syndrome | Original Research

Population Pharmacokinetic Modeling to Support Trofinetide Dosing for the Treatment of Rett Syndrome

Authors: Mona Darwish, Julie Passarell, Kelly Maxwell, James M. Youakim, Heather Bradley, Kathie M. Bishop

Published in: Advances in Therapy | Issue 2/2025

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Abstract

Introduction

Oral trofinetide administered using a body weight-banded dosing regimen was approved in the US for the treatment of Rett syndrome (RTT) in patients aged ≥ 2 years. This approval was principally based on efficacy and safety findings of the phase 3 LAVENDER study in girls and women aged 5–20 years with RTT and extended to younger children aged 2–4 years with supporting data from the DAFFODIL study. Weight-banded dosing regimens were selected based on early clinical population pharmacokinetic (popPK) modeling and different scenario simulations. We report the development and application of an updated popPK model to confirm that steady-state trofinetide exposures achieved in individual patients in the LAVENDER study were within target exposure range.

Methods

A previously developed popPK model using data from nine clinical studies was updated based on 13 clinical studies of trofinetide in healthy volunteers and pediatric and adult patients, including the LAVENDER study. PopPK model and empiric individual Bayesian pharmacokinetic parameter estimates were used to generate trofinetide exposures. Covariate data from the pharmacokinetic dataset from LAVENDER study subjects (n = 92) were used to estimate individual steady-state trofinetide exposure (area under concentration–time curve over 0–12 h [AUC0–12]). Steady-state exposures in individual patients in the LAVENDER study were used to confirm that the dosing regimens resulted in exposures within the target range.

Results

Among 5- to 20-year-olds receiving the LAVENDER BID dosing regimen [trofinetide 6 g (12‒20 kg), 8 g (> 20‒35 kg), 10 g (> 35‒50 kg), and 12 g (> 50 kg)], simulated AUC0-12 values overlapped with the target exposure range; median AUC0–12 values were within target exposure range for all weight bands.

Conclusions

PopPK model-based simulations confirm that weight-banded trofinetide dosing used in LAVENDER in girls and women aged 5–20 years with RTT achieved target exposure.
Graphical abstract available for this article.

Graphical Abstract

Appendix
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Literature
2.
go back to reference Kirby RS, Lane JB, Childers J, et al. Longevity in Rett syndrome: analysis of the North American Database. J Pediatr. 2010;156(135–138): e131. Kirby RS, Lane JB, Childers J, et al. Longevity in Rett syndrome: analysis of the North American Database. J Pediatr. 2010;156(135–138): e131.
4.
go back to reference Neul JL, Benke TA, Marsh ED, et al. The array of clinical phenotypes of males with mutations in Methyl-CpG binding protein 2. Am J Med Genet B Neuropsychiatr Genet. 2019;180:55–67.CrossRefPubMed Neul JL, Benke TA, Marsh ED, et al. The array of clinical phenotypes of males with mutations in Methyl-CpG binding protein 2. Am J Med Genet B Neuropsychiatr Genet. 2019;180:55–67.CrossRefPubMed
5.
6.
go back to reference Glaze DG, Neul JL, Kaufmann WE, et al. Double-blind, randomized, placebo-controlled study of trofinetide in pediatric Rett syndrome. Neurology. 2019;92:e1912–25.CrossRefPubMedPubMedCentral Glaze DG, Neul JL, Kaufmann WE, et al. Double-blind, randomized, placebo-controlled study of trofinetide in pediatric Rett syndrome. Neurology. 2019;92:e1912–25.CrossRefPubMedPubMedCentral
7.
go back to reference Glaze DG, Neul JL, Percy A, et al. A double-blind, randomized, placebo-controlled clinical study of trofinetide in the treatment of Rett syndrome. Pediatr Neurol. 2017;76:37–46.CrossRefPubMed Glaze DG, Neul JL, Percy A, et al. A double-blind, randomized, placebo-controlled clinical study of trofinetide in the treatment of Rett syndrome. Pediatr Neurol. 2017;76:37–46.CrossRefPubMed
9.
go back to reference Darwish M, Passarell J, Youakim JM, Bradley H, Bishop KM. Exposure-response efficacy modeling to support trofinetide dosing in individuals with Rett syndrome. Adv Ther. 2024;41:1462–80.CrossRefPubMedPubMedCentral Darwish M, Passarell J, Youakim JM, Bradley H, Bishop KM. Exposure-response efficacy modeling to support trofinetide dosing in individuals with Rett syndrome. Adv Ther. 2024;41:1462–80.CrossRefPubMedPubMedCentral
10.
go back to reference Darwish M, Youakim JM, Harlick J, DeKarske D, Stankovic S. A phase 1, open-label study to evaluate the effects of food and evening dosing on the pharmacokinetics of oral trofinetide in healthy adult subjects. Clin Drug Investig. 2022;42:513–24.CrossRefPubMedPubMedCentral Darwish M, Youakim JM, Harlick J, DeKarske D, Stankovic S. A phase 1, open-label study to evaluate the effects of food and evening dosing on the pharmacokinetics of oral trofinetide in healthy adult subjects. Clin Drug Investig. 2022;42:513–24.CrossRefPubMedPubMedCentral
11.
go back to reference Darwish M, Nunez R, Youakim JM, Robertson P Jr. Characterization of the pharmacokinetics and mass balance of a single oral dose of trofinetide in healthy male subjects. Clin Drug Investig. 2024;44:21–33.CrossRefPubMed Darwish M, Nunez R, Youakim JM, Robertson P Jr. Characterization of the pharmacokinetics and mass balance of a single oral dose of trofinetide in healthy male subjects. Clin Drug Investig. 2024;44:21–33.CrossRefPubMed
12.
go back to reference Darwish M, Youakim JM, DeKarske D, Stankovic S. A phase 1, ascending-dose study to assess the potential effects of trofinetide on QTc interval, safety and tolerability, and pharmacokinetics in healthy adults [poster]. Presented at Child Neurology Society; October 12–15, 2022; Cincinatti, OH, USA. Darwish M, Youakim JM, DeKarske D, Stankovic S. A phase 1, ascending-dose study to assess the potential effects of trofinetide on QTc interval, safety and tolerability, and pharmacokinetics in healthy adults [poster]. Presented at Child Neurology Society; October 12–15, 2022; Cincinatti, OH, USA.
13.
go back to reference Bergstrand M, Hooker AC, Wallin JE, Karlsson MO. Prediction-corrected visual predictive checks for diagnosing nonlinear mixed-effects models. AAPS J. 2011;13:143–51.CrossRefPubMedPubMedCentral Bergstrand M, Hooker AC, Wallin JE, Karlsson MO. Prediction-corrected visual predictive checks for diagnosing nonlinear mixed-effects models. AAPS J. 2011;13:143–51.CrossRefPubMedPubMedCentral
Metadata
Title
Population Pharmacokinetic Modeling to Support Trofinetide Dosing for the Treatment of Rett Syndrome
Authors
Mona Darwish
Julie Passarell
Kelly Maxwell
James M. Youakim
Heather Bradley
Kathie M. Bishop
Publication date
18-12-2024
Publisher
Springer Healthcare
Published in
Advances in Therapy / Issue 2/2025
Print ISSN: 0741-238X
Electronic ISSN: 1865-8652
DOI
https://doi.org/10.1007/s12325-024-03056-9

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