Assessing Experiences With Trofinetide for Rett Syndrome: Interviews With Caregivers of Participants in Clinical Trials.

Purpose: Rett syndrome (RTT) is a rare neurodevelopmental disorder that mainly affects girls and women. Trofinetide is approved for the treatment of RTT in adults and children aged ≥2 years. To gain insight into experiences with RTT and effects of trofinetide treatment at different stages of RTT, interviews with caregivers of individuals with RTT were conducted upon their exit from the open-label trofinetide trials.

International workshop: what is needed to ensure outcome measures for Rett syndrome are fit-for-purpose for clinical trials? June 7, 2023, Nashville, USA.

Introduction: The clinical, research and advocacy communities for Rett syndrome are striving to achieve clinical trial readiness, including having fit-for-purpose clinical outcome assessments. This study aimed to (1) describe psychometric properties of clinical outcome assessment for Rett syndrome and (2) identify what is needed to ensure that fit-for-purpose clinical outcome assessments are available for clinical trials.

Methods: Clinical outcome assessments for the top 10 priority domains identified in the Voice of the Patient Report for Rett syndrome were compiled and available psychometric data were extracted.

Population Pharmacokinetics of Trofinetide in a Pediatric Population Aged 2-4 Years with Rett Syndrome.

Introduction: Weight-banded trofinetide dosing improved physician- and caregiver-rated efficacy measures and had acceptable tolerability in patients aged 2‒4 years (DAFFODIL study) and 5‒20 years (LAVENDER study) with Rett syndrome (RTT). Selection of weight-banded dosing regimens for these studies was based on population pharmacokinetic (popPK) modeling and exposure simulations. This study applied an updated popPK model to confirm steady-state trofinetide exposures achieved in DAFFODIL patients were within target range.

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

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.

Physiologically-Based Pharmacokinetic Modeling of Trofinetide in Moderate Renal Impairment for Phase 1 Clinical Study Dose Selection with Model Validation.

Background And Objectives: Trofinetide, the first approved treatment for Rett syndrome (RTT), is primarily excreted unchanged in the urine; therefore, it is important to assess the extent to which the exposure is affected in patients with renal impairment. Pharmacokinetic modeling overcomes the challenge of dose finding in phase 1 studies that include special populations where there is the potential for increased exposure to study drug. The objectives of this phase 1 study were to evaluate trofinetide pharmacokinetics, safety, and tolerability in a population with moderate renal impairment and normal renal function.