Evaluation of Elexacaftor/Tezacaftor/Ivacaftor (ELX/TEZ/IVA) in Cystic Fibrosis (CF) Participants 12 to Less Than 24 Months of Age

A Phase 3, Open-label Study Evaluating the Pharmacokinetics, Safety, and Tolerability of Elexacaftor/Tezacaftor/Ivacaftor in Cystic Fibrosis Subjects 12 to Less Than 24 Months of Age

This study will evaluate the pharmacokinetics (PK), safety, tolerability, pharmacodynamics (PD), and efficacy of ELX/TEZ/IVA in CF subjects 12 to less than (<) 24 months of age.

Study Overview

• Status: Completed
• Conditions: Cystic Fibrosis
• Intervention / Treatment: Drug: ELX/TEZ/IVA; Drug: IVA

• Study Type: Interventional
• Enrollment (Actual): 70
• Phase: Phase 3

Contacts and Locations

Study Locations

• Australia
  • Nedlands, Australia
    • Telethon Kids Institute
  • Parkville, Australia
    • The Royal Children's Hospital
  • South Brisbane, Australia
    • Queensland Children's Hospital
  • Westmead, Australia
    • The Children's Hospital at Westmead
• Canada
  • Toronto, Canada
    • The Hospital for Sick Children
  • Vancouver, Canada
    • British Columbia Children's Hospital
• Denmark
  • Copenhagen, Denmark
    • Juliane Marie Center, Rigshospitalet
• Germany
  • Berlin, Germany
    • Charite Paediatric Pulmonology Department
  • Essen, Germany
    • Kinderklinik III, Abt. fur Pneumologie
  • Hanover, Germany
    • Medizinische Hochschule Hannover
• Netherlands
  • Rotterdam, Netherlands
    • Erasmus Medical Center / Sophia Children's Hospital
• Switzerland
  • Bern, Switzerland
    • Inselspital - Universitaetsspital Bern
  • Zurich, Switzerland
    • Kinderspital Zuerich
• United Kingdom
  • Cardiff, United Kingdom
    • Children and Young Adults Research Unit
  • Leeds, United Kingdom
    • Leeds General Infirmary
  • Liverpool, United Kingdom
    • Alder Hey Children's NHS Foundation Trust
  • London, United Kingdom
    • Royal Brompton Hospital
  • London, United Kingdom
    • Great Ormond Street Hospital for Children
  • Southampton, United Kingdom
    • Southampton General Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child
• Accepts Healthy Volunteers: No

Description

Key Inclusion Criteria:

Participants who have at least 1 F508del mutation in the CF transmembrane conductance regulator (CFTR) gene or another ELX/TEZ/IVA-responsive CFTR mutation

Key Exclusion Criteria:

History of any illness or any clinical condition that, in the opinion of the investigator, might either confound the results of the study or pose an additional risk in administering study drug(s) to the participant

Other protocol defined Inclusion/Exclusion criteria may apply.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Non-Randomized
• Interventional Model: Sequential Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Part A; Participants will receive ELX/TEZ/IVA in the morning and IVA in the evening.	Drug: ELX/TEZ/IVA; Fixed-dose combination granules for oral administration.; Other Names: VX-445/VX-661/VX-770; elexacaftor/tezacaftor/ivacaftor; Drug: IVA; Granules for oral administration; Other Names: VX-770; ivacaftor
Experimental: Part B; Participants will receive ELX/TEZ/IVA in the morning and IVA in the evening with the dose(s) to be based on the outcome of Part A.	Drug: ELX/TEZ/IVA; Fixed-dose combination granules for oral administration.; Other Names: VX-445/VX-661/VX-770; elexacaftor/tezacaftor/ivacaftor; Drug: IVA; Granules for oral administration; Other Names: VX-770; ivacaftor

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Part A: Observed Pre-dose Concentration (Ctrough) of ELX, TEZ, IVA, and their Relevant Metabolites	Day 1 up to Day 15
Part A: Safety and Tolerability as Assessed by Number of Participants with Adverse Events (AEs) and Serious Adverse Events (SAEs)	Day 1 up to Day 43
Part B: Safety and Tolerability as Assessed by Number of Participants with Adverse Events (AEs) and Serious Adverse Events (SAEs)	Day 1 up to Week 28

Secondary Outcome Measures

Outcome Measure	Time Frame
Part B: Absolute Change in Sweat Chloride (SwCl)	From Baseline Through Week 24
Part B: Observed Pre-dose Concentration (Ctrough) of ELX, TEZ, IVA, and their Relevant Metabolites	Day 15 up to Week 16

Collaborators and Investigators

• Sponsor: Vertex Pharmaceuticals Incorporated

Study record dates

Study Major Dates

• Study Start (Actual): June 27, 2023
• Primary Completion (Actual): September 4, 2025
• Study Completion (Actual): September 4, 2025

Study Registration Dates

• First Submitted: May 19, 2023
• First Submitted That Met QC Criteria: May 19, 2023
• First Posted (Actual): May 31, 2023

Study Record Updates

• Last Update Posted (Estimated): October 6, 2025
• Last Update Submitted That Met QC Criteria: October 3, 2025
• Last Verified: October 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Genetic Diseases, Inborn; Respiratory Tract Diseases; Digestive System Diseases; Lung Diseases; Infant, Newborn, Diseases; Pancreatic Diseases; Congenital, Hereditary, and Neonatal Diseases and Abnormalities; Cystic Fibrosis; Molecular Mechanisms of Pharmacological Action; Membrane Transport Modulators; Chloride Channel Agonists; elexacaftor, ivacaftor, tezacaftor drug combination; ivacaftor
• Other Study ID Numbers: VX22-445-122; 2023-503230-49-00 (Other Identifier: EU CT)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Details on Vertex data sharing criteria and process for requesting access can be found at: https://www.vrtx.com/independent-research/clinical-trial-data-sharing

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: Yes