# A Study Evaluating the Safety and Efficacy of VX-659 Combination Therapy in Subjects With Cystic Fibrosis

> **NCT03224351** · PHASE2 · COMPLETED · sponsor: **Vertex Pharmaceuticals Incorporated** · enrollment: 124 (actual)

## Conditions studied

- Cystic Fibrosis

## Interventions

- **DRUG:** VX-659
- **DRUG:** TEZ/IVA
- **DRUG:** IVA
- **DRUG:** Placebo (matched to VX-659/TEZ/IVA)
- **DRUG:** TEZ
- **DRUG:** VX-561
- **DRUG:** Placebo (matched to VX-659/TEZ/VX-561)

## Key facts

- **NCT ID:** NCT03224351
- **Lead sponsor:** Vertex Pharmaceuticals Incorporated
- **Sponsor class:** INDUSTRY
- **Phase:** PHASE2
- **Study type:** INTERVENTIONAL
- **Status:** COMPLETED
- **Start date:** 2017-08-08
- **Primary completion:** 2018-02-28
- **Final completion:** 2018-02-28
- **Target enrollment:** 124 (ACTUAL)
- **Last updated:** 2021-04-22


## Primary source

ClinicalTrials.gov registry: https://clinicaltrials.gov/study/NCT03224351

## Citation

> US National Library of Medicine, ClinicalTrials.gov registration NCT03224351, "A Study Evaluating the Safety and Efficacy of VX-659 Combination Therapy in Subjects With Cystic Fibrosis". Retrieved via AI Analytics 2026-05-24 from https://api.ai-analytics.org/clinical/NCT03224351. Licensed CC0.

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