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Drug & research development » Clinical trials » NCT00909532

Study of Ivacaftor in Cystic Fibrosis Subjects Aged 12 Years and Older With the G551D Mutation (STRIVE)

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

Clinical Trials gov number: NCT00909532

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Purpose: To evaluate the efficacy and safety of ivacaftor in CF patients aged ≥12 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

  • Confirmed diagnosis of CF and G551D mutation in ≥1 allele
  • Forced expiratory volume in 1 second (FEV1) of 40–90% (inclusive) of predicted normal for age, gender, and height at screening
  • No clinically significant abnormalities that would have interfered with the study assessments, as judged by the investigator
  • Willing to use highly effective birth control methods during the study


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

Number of Participants
101-1000 (≥12 years)

Primary Endpoint

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

Secondary Endpoint

  • Absolute mean change from baseline (BL) in percent predicted FEV1 through Week 48
  • Absolute change from BL in Cystic Fibrosis Questionnaire-Revised score through Week 24 and Week 48 (Respiratory Domain Score, Pooled)
  • Absolute change from BL in sweat chloride concentration through Week 24 and Week 48
  • Time-to-first pulmonary exacerbation through Week 24 and Week 48
  • Absolute change from BL in weight through 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.



Ramsey BW, Davies J, McElvaney NG, Tullis E, Bell SC, Dřevínek P, Griese M, McKone EF, Wainwright CE, Konstan MW, Moss R, Ratjen F, Sermet-Gaudelus I, Rowe SM, Dong Q, Rodriguez S, Yen K, Ordoñez C, Elborn JS; VX08-770-102 Study Group. A CFTR potentiator in patients with cystic fibrosis and the G551D mutation. N Engl  J Med. 2011 Nov 3;365(18):1663-72. doi: 10.1056/NEJMoa1105185. PubMed PMID: 22047557; PubMed Central PMCID: PMC3230303.

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