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Drug & research development » Clinical trials » NCT00865904

Study of VX-809 in Cystic Fibrosis Subjects With the ∆F508-CFTR Gene Mutation

Official title: A Randomized, Double-Blind, Placebo-Controlled, Multiple Dose Study of VX-809 to Evaluate Safety, Pharmacokinetics, and Pharmacodynamics of VX-809 in Cystic Fibrosis Subjects Homozygous for the ∆F508-CFTR Gene Mutation

Clinical Trials gov number: NCT00865904

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Purpose: To evaluate the safety, tolerability, pharmacokinetics, and pharmacodynamics of VX-809 in CF patients who have the ∆F508-CFTR gene mutation.

Phase: 2

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

Study sponsor: Vertex Pharmaceuticals Incorporated

  • Confirmed diagnosis of CF with ∆F508-CFTR mutation in both alleles
  • FEV1 ≥40% of predicted normal for age, gender, and height
  • Weight ≥40 kg and body mass index ≥18.5
  • Screening laboratory values, tests, and physical examination within acceptable ranges
  • Negative pregnancy test (for women of child-bearing potential)
  • Able and willing to follow contraceptive requirements
  • Willing to remain on a stable medication regimen for the duration of study participation


Geographical Location
Belgium, Canada, Germany, Netherlands, United States

Number of Participants
51-100 (≥18 years)

Primary Endpoint

Safety and tolerability assessments based on adverse events, hematology, clinical chemistry, urinalysis, electrocardiograms, vital signs, and physical examinations (28 days)

Secondary Endpoint

  • Pharmacodynamic assessments using spirometry (FVC, FEV1, and FEF25-75), sweat chloride, nasal potential difference (NPD), and the CF Questionnaire-Revised (CFQ-R), and evaluation of pharmacokinetic parameters (28 days)

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  • Active Comparator: 1

     Dose A VX-809 oral capsule once a day for 28 days

  • Active Comparator: 2

     Dose B VX-809 oral capsule once a day for 28 days

  • Active Comparator: 3

     Dose C VX-809 oral capsule once a day for 28 days

  • Active Comparator: 4

     Dose D VX-809 oral capsule once a day for 28 days

  • Placebo Comparator: 5

     Placebo oral capsule once a day for 28 days



Clancy JP, Rowe SM, Accurso FJ, Aitken ML, Amin RS, Ashlock MA, Ballmann M, Boyle MP, Bronsveld I, Campbell PW, De Boeck K, Donaldson SH, Dorkin HL, Dunitz JM, Durie PR, Jain M, Leonard A, McCoy KS, Moss RB, Pilewski JM, Rosenbluth DB, Rubenstein RC, Schechter MS, Botfield M, Ordoñez CL, Spencer-Green GT, Vernillet L, Wisseh S, Yen K, Konstan MW. Results of a phase IIa study of VX-809, an investigational CFTR corrector compound, in subjects with cystic fibrosis homozygous for the F508del-CFTR mutation. Thorax. 2012 Jan;67(1):12-8. doi: 10.1136/thoraxjnl-2011-200393. Epub 2011 Aug 8. PubMed PMID: 21825083; PubMed Central PMCID: PMC3746507.

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