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Drug & research development » Clinical trials » NCT00909727

Study of Ivacaftor in Cystic Fibrosis Subjects Aged 6 to 11 Years With the G551D Mutation (ENVISION)

Official title: A Phase 3, 2-Part, Randomized, Double-Blind, Placebo-Controlled, Parallel-Group Study to Evaluate the Pharmacokinetics, Efficacy and Safety of VX-770 in Subjects Aged 6 to 11 Years With Cystic Fibrosis and the G551D Mutation

Clinical Trials gov number: NCT00909727

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Purpose: To evaluate the efficacy and safety of ivacaftor in CF patients aged 6–11 years who have the G551D mutation in the cystic fibrosis transmembrane conductance regulator (CFTR) gene.

Phase: 3

Type: Interventional, randomized, double-blind, parallel assignment

Study sponsor: Vertex Pharmaceuticals Incorporated; Cystic Fibrosis Foundation Therapeutics

  • Weighing ≥15kg
  • Confirmed diagnosis of CF and G551D mutation in ≥1 allele
  • Forced expiratory volume in 1 second (FEV1) of 40–105% (inclusive) of predicted normal for age, gender, and height (Knudson standards) at screening
  • Able to swallow tablets
  • As judged by the investigator, parent or legal guardian and subject must have been able to understand protocol requirements, restrictions, and instructions, and the parent or legal guardian should have been able to ensure that the subject complied with, and was likely to complete, the study as planned
  • Parent or legal guardian must have signed the informed consent form and corresponding assent must be obtained from the subject
  • Willing to use ≥1 highly effective birth control method during the study
  • No clinically significant abnormalities that would have interfered with the study assessments, as judged by the investigator


Geographical Location
Australia, Canada, France, Germany, Ireland, United Kingdom, United States

Number of Participants
51-100 (6-11 years)

Primary Endpoint

Absolute change from baseline in percent predicted forced expiratory volume in 1 second (FEV1) through Week 24

Secondary Endpoint

  • Absolute change from baseline (BL) in percent predicted forced expiratory volume in 1 second (FEV1) through Week 48
  • Absolute change from BL in Cystic Fibrosis Questionnaire-Revised through Week 24 and Week 48 (Respiratory Domain Score, Children)
  • Absolute change from BL in sweat chloride concentration through Week 24 and Week 48
  • Absolute change from BL in weight at Week 24 and Week 48

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  • Placebo Comparator:

     Subjects who received placebo every 12 hours (q12h) for up to 48 weeks.

  • Experimental:

     Subjects who received 150 mg of ivacaftor q12h for up to 48 weeks



Davies JC, Wainwright CE, Canny GJ, Chilvers MA, Howenstine MS, Munck A, Mainz JG, Rodriguez S, Li H, Yen K, Ordoñez CL, Ahrens R; VX08-770-103 (ENVISION) Study Group. Efficacy and safety of ivacaftor in patients aged 6 to 11 years with cystic fibrosis with a G551D mutation. Am J Respir Crit Care Med. 2013 Jun 1;187(11):1219-25. doi: 10.1164/rccm.201301-0153OC. PubMed PMID: 23590265; PubMed Central PMCID: PMC3734608.

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