Search

Page Title

Clinical Trial Finder

Back to the Clinical Trial Finder

Restore CFTR Protein Completed with Results

Phase 3 study of tezacaftor (VX-661) combination drug in children with cystic fibrosis (Vertex VX15-661-113)

This study evaluated the safety and tolerability of the drug tezacaftor (VX-661) in combination with ivacaftor (Kalydeco®) in children with CF. This study was for children who have two copies of the F508del mutation or one copy of F508del and a second mutation that is either residual function or results in a gating defect and responds to ivacaftor.

 This study had two parts and was open-label, meaning all participants received the study treatment. Part A evaluated the safety, tolerability, and how the body processes tezacaftor/ivacaftor over 14 days. Participants weighing less than 25kg received 50mg of tezacaftor once daily and 75mg of ivacaftor every 12 hours. Participants weighing more than 25kg received 50mg of tezacaftor once daily and 150mg of ivacaftor every 12 hours.  The information collected in Part A determined the weight cutoffs and the doses tested in Part B. Part B evaluated tezacaftor/ivacaftor for 24 weeks. Participants weighing less than 40kg received 50mg of tezacaftor once daily and 75mg of ivacaftor every 12 hours. Participants weighing more than 40kg received 100mg of tezacaftor once daily and 150mg of ivacaftor every 12 hours. At the end of Part B, participants were given the option to continue treatment by enrolling in a 96-week open-label extension study.

Eligibility

See other primary eligibility criteria for more information.

  • Age:

    6 Years to 11 Years

  • Mutation(s):

    Two Copies F508del or One Copy F508del

  • FEV1% Predicted:

    40% or greater

For more information about the results of this study and where it was conducted, visit ClinicalTrials.gov.

Other Primary Eligibility Criteria

This study is for children with CF who have two copies of the F508del CFTR mutation, or one copy of F508del and a second CFTR mutation that is predicted to have residual function or a gating mutation that is responsive to ivacaftor. Please contact a research coordinator to find out if your mutation is eligible for this study.

Study Results

  • What We Learned:

    This study showed that tezacaftor (VX-661) in combination with ivacaftor (Kalydeco®) was overall well-tolerated, and it resulted in a decrease in sweat chloride concentrations and an improvement in lung function for younger children.

  • Primary Findings:

    Effectiveness:

    Safety:

    This study was conducted between November 2016 and September 2018. In Part A, 13 participants completed treatment. In Part B, 67 participants completed treatment.

     

    The primary endpoint in Part A was to determine how the body processes the drug. Part A found that in participants 6-11 years old, the body processes tezacaftor/ivacaftor similar to those 12 years and older, as shown in previous studies of tezacaftor/ivacaftor. Additionally, tezacaftor/ivacaftor was well-tolerated in Part A. There were no treatment-related adverse events that caused participants to pause or stop taking the study treatment.

     

    The primary endpoint in Part B was safety and tolerability. Researchers studied a variety of measurements, including treatment-related adverse events, electrocardiograms (ECGs), spirometry, eye examinations, and other measures. In Part B, tezacaftor/ivacaftor was generally well-tolerated and the safety profile was similar to what was seen in the study with children aged 12 and older. One participant withdrew from the study due to constipation. Seven (10%) participants had elevated liver enzymes greater than 3 times the upper limit of normal, though none had to stop taking the study treatment.

     

    The study also found that tezacaftor/ivacaftor resulted in reduced sweat chloride concentrations (mean absolute change in sweat chloride was -14.5 mmol/L from the beginning of the study through week 24). Researchers also saw an improvement in lung function (mean absolute change in ppFEV1 of 0.9% from the beginning of the study through week 24).

  • Citation:

    J Cyst Fibros ;DOI 10.1016/j.jcf.2019.06.009 [Epub ahead of print];S1569-1993(19):30813-30816

For current information about the overall development status of this drug, please check the Drug Development Pipeline.

Study Design

  • Study Type: ?more info

    Interventional

  • Randomized Study: ?more info

    No

  • Placebo Controlled: ?more info

    No

  • Length of Participation:

    28 weeks

  • Number of Study Visits:

    9

Additional Information

Eligibility

See other primary eligibility criteria for more information.

  • Age:

    6 Years to 11 Years

  • Mutation(s):

    Two Copies F508del or One Copy F508del

  • FEV1% Predicted:

    40% or greater

For more information about the results of this study and where it was conducted, visit ClinicalTrials.gov.

Other Primary Eligibility Criteria

This study is for children with CF who have two copies of the F508del CFTR mutation, or one copy of F508del and a second CFTR mutation that is predicted to have residual function or a gating mutation that is responsive to ivacaftor. Please contact a research coordinator to find out if your mutation is eligible for this study.

CONTACT THE CLINICAL TRIAL NAVIGATOR

Get personalized assistance and answers to your clinical trial questions.

Learn More

Sign up for clinical trial alerts

Get email updates about clinical trials that matter to you.

Check the Drug Development Pipeline

We’re attacking CF from every angle. Learn about the status of CF drugs in development.

Learn More