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Drug & research development » Clinical trials » NCT02070744

Study to Evaluate Safety and Efficacy of VX-661 in Combination With Ivacaftor in Subjects With Cystic Fibrosis, Homozygous for the F508del-CFTR Mutation With an Open-Label Expansion

Official title: A Phase 2, Randomized, Multicenter, Double Blind, Placebo Controlled Study to Evaluate Safety, Efficacy, Pharmacokinetics, and Pharmacodynamics of VX-661 in Combination With Ivacaftor for 12 Weeks in Subjects With Cystic Fibrosis, Homozygous for the F508del CFTR Mutation With an Open-Label Extension

Clinical Trials gov number: NCT02070744

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Purpose: To evaluate the safety and efficacy of VX-661 in combination with ivacaftor in CF patients who are homozygous for F508del CFTR (cystic fibrosis transmembrane conductance regulator) mutation.

Phase: 2

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

Study sponsor: Vertex Pharmaceuticals Incorporated

  • Male or female homozygous for the F508del CFTR mutation
  • FEV1 ≥40% and ≤90% of predicted normal for age, sex, and height
  • Stable CF disease as judged by the investigator

Ivacaftor, VX-661

Geographical Location
United States

Number of Participants
≤50 (≥18 years)

Primary Endpoint

  • Safety as determined by adverse events, physical examination, clinical laboratory values, standard digital electrocardiograms, vital signs and pulse oximetry from baseline to Week 16

Secondary Endpoint

From baseline to Week 12

  • Absolute change in percent predicted forced expiratory volume in 1 second (FEV1)
  • Relative change in percent predicted FEV1

– Absolute change in body weight

  • Absolute change in body mass index

– Absolute change in the respiratory domain of the Cystic Fibrosis Questionnaire-Revised

  • Absolute change in sweat chloride

From baseline to Week 16

  • PK parameters estimates of VX 661 and ivacaftor and their respective metabolites, derived from plasma concentration-time data

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  • Experimental: Group 1

      VX-661 + ivacaftor

      VX-661 placebo + ivacaftor placebo

     (every 12 hours [q12h] schedule)

  • Experimental: Group 2

      VX-661 + ivacaftor

      VX-661 placebo + ivacaftor placebo

      (once daily [qd] and q12h schedule)

View Trial Results