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NCT03911713 · ClinicalTrials.gov registry record · Phase 2

A Phase 2 Study to Evaluate Efficacy and Safety of VX-561 in Subjects Aged 18 Years and Older With Cystic Fibrosis

A Phase 2 study of Cystic Fibrosis, sponsored by Vertex Pharmaceuticals Incorporated.

Completed
Registry status
Phase 2
Development phase
77
Enrollment target
20
Study locations

NCT03911713: Completed Phase 2 study of Cystic Fibrosis, sponsored by Vertex Pharmaceuticals Incorporated.

NCT03911713 is a Phase 2 study of Cystic Fibrosis that has completed, run by Vertex Pharmaceuticals Incorporated. The registered enrollment target is 77 participants, below the 179-participant average among 169 other Cystic Fibrosis trials with a reported enrollment target (57% lower). The trial reports 20 study locations across 16 states. According to ClinicalTrials.gov, the official US trial registry.

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The verdict

NCT03911713, a Phase 2 study of Cystic Fibrosis, has completed, sponsored by Vertex Pharmaceuticals Incorporated.

COMPLETED
Registry status
Phase 2
Development phase
77 participants
Enrollment target
20
Study locations

Study Summary

The purpose of this study is to evaluate the efficacy, safety, pharmacodynamic (PD) and pharmacokinetic (PK) effect of VX-561.

Primary Outcome

FEV1 is the volume of air that can forcibly be blown out in one second, after full inspiration.

Conditions Studied

Interventions

  • DRUG Placebo
  • DRUG IVA
  • DRUG VX-561

Study Locations (20)

California

  • Miller Children's Hospital / Long Beach Memorial - Long Beach
  • UCSF Gateway Medical Center - San Francisco

Florida

  • University of Miami Miller School of Medicine - Miami
  • Central Florida Pulmonary Group, PA - Orlando

Massachusetts

  • Massachusetts General Hospital Cystic Fibrosis Center Clinical Research Center - Boston
  • Boston Children's Hospital - Boston

Missouri

  • Cardinal Glennon Children's Hospital - St Louis
  • Washington University School of Medicine / St. Louis Children's Hospital - St Louis

Alabama

  • University of Alabama at Birmingham - Birmingham

Arizona

  • Banner University of Arizona Medical Center - Tucson

Colorado

  • National Jewish Health - Denver

Indiana

  • Indiana University - Indianapolis

Trial Details

FieldValue
Enrollment Target 77 participants
Start Date 2019-04-17
Est. Completion 2020-08-20
Phase Phase 2
Vertex Pharmaceuticals Incorporated

191 total trials

What the finished NCT03911713 record still lists

NCT03911713 is an interventional study that assigns participants to a tested intervention. The registry caps enrollment at 77 participants, a relatively small participant target, below the 179-participant average among 169 other Cystic Fibrosis trials with a reported enrollment target (57% lower).

The record links to 1 condition, with Cystic Fibrosis appearing as the primary indexed condition, and to 3 interventions - of which Placebo is the first listed.

NCT03911713 names 20 study sites across 16 states, led by California, Florida, Massachusetts.

Frequently Asked Questions

What is clinical trial NCT03911713 about?

NCT03911713 is a clinical study titled "A Phase 2 Study to Evaluate Efficacy and Safety of VX-561 in Subjects Aged 18 Years and Older With Cystic Fibrosis". The purpose of this study is to evaluate the efficacy, safety, pharmacodynamic (PD) and pharmacokinetic (PK) effect of VX-561.

What is the current status of trial NCT03911713?

This trial is currently completed. It is a Phase 2 study. The enrollment target is 77 participants. The study started on 2019-04-17. Estimated completion is 2020-08-20.

What conditions does trial NCT03911713 study?

This clinical trial studies the following conditions: Cystic Fibrosis.

What interventions are being tested in trial NCT03911713?

The interventions under investigation include: Placebo (DRUG), IVA (DRUG), VX-561 (DRUG).

Who is sponsoring clinical trial NCT03911713?

This trial is sponsored by Vertex Pharmaceuticals Incorporated, which has 191 total clinical trials registered on ClinicalTrials.gov.

Where is trial NCT03911713 being conducted?

This trial has 20 study locations across Alabama, Arizona, California, Colorado, Florida. Contact the study sites directly through ClinicalTrials.gov for enrollment availability.

Similar trials for Cystic Fibrosis

Matched on the same primary condition, ranked to surface studies in the same phase first, then by recruiting status, no relevance scoring or editorial curation.

Where NCT03911713's enrollment target sits among peer trials

77 74th of 169 higher than 96 of 169 other Cystic Fibrosis trials

participants (enrollment target), bucketed by value

Each bar is a band; taller bars hold more other Cystic Fibrosis trials. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.

Source ClinicalTrials.gov registry export · 2026-08-08

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Source: ClinicalTrials.gov NCT03911713, the US trial registry maintained by the National Library of Medicine. NCT03911713 (small enrollment · wide site footprint · completed) retrieved and formatted by PlainTrial, see methodology.