Trial record 1 of 1 for:    nct02057458
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Blood Flow and Vascular Function in Cystic Fibrosis (CF-FLOW)

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT02057458
Recruitment Status : Active, not recruiting
First Posted : February 7, 2014
Last Update Posted : June 27, 2018
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Information provided by (Responsible Party):
Ryan Harris, National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)

February 4, 2014
February 7, 2014
June 27, 2018
April 2014
July 2018   (Final data collection date for primary outcome measure)
  • Exercise Capacity [ Time Frame: 1 hour ]
    Exercise Capacity will be determined one hour after ingestion of 50 mg Sildenafil
  • Exercise Capacity [ Time Frame: 4 weeks ]
    Exercise capacity will be determined after taking 20 mg of Sildenafil thrice daily for four weeks.
Same as current
Complete list of historical versions of study NCT02057458 on Archive Site
  • Flow-Mediated Dilation (FMD) [ Time Frame: 1 hour and 4 weeks ]
    Brachial artery FMD induced by reactive hyperemia will be used to assess vascular endothelial function.
  • Arterial Stiffness Evaluation (PWV) [ Time Frame: 1 hour and 4 weeks ]
    A tonometer will be gently applied on the carotid artery and then the femoral artery and the radial artery to record how fast blood flows between each of the points.
  • Physio Flow [ Time Frame: 1 hour and 4 weeks ]
    Six surface electrodes will be placed on the body. 2 on the neck, 2 on the chest, and 2 on the back in order to measure parameters of the heart during exercise.
Same as current
Not Provided
Not Provided
Blood Flow and Vascular Function in Cystic Fibrosis
Role of Blood Flow and Vascular Function on Exercise Capacity in Cystic Fibrosis
Cystic fibrosis (CF) has many health consequences. A reduction in the ability to perform exercise in patients with CF is related to greater death rates, steeper decline in lung function, and more frequent lung infections. However, the physiological mechanisms for this reduced exercise capacity are unknown. The investigators laboratory recently published the first evidence of systemic vascular dysfunction in patients with CF. Therefore, it is reasonable to suspect that the blood vessels are involved with exercise intolerance in CF. This study will look at how 1) blood flow and 2) artery function contribute to exercise capacity in CF.
The most disturbing aspect of Cystic Fibrosis (CF) is the associated premature death. Low exercise capacity predicts death in patients with CF and is also associated with a steeper decline in lung function and more lung infections. A critical barrier to improving exercise tolerance in patients with CF is the investigators lack of knowledge regarding the different physiological mechanisms which contribute to their lower exercise capacity. We have compelling data to indicate that the blood vessels may contribute to the low exercise capacity in CF. The impact of this proof of concept investigation will test Phosphodiesterase Type 5 inhibitors (PDE5) inhibitors as a potential therapy in CF and will explore blood flow and endothelial function as potential mechanisms which contribute to exercise intolerance in CF. Improvements in exercise capacity will not only contribute to a better quality of live for patients with CF, it will also increase longevity in these patients.
Phase 2
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Double (Participant, Investigator)
Primary Purpose: Treatment
Cystic Fibrosis
  • Drug: Acute (1 hour) Sildenafil
    Exercise capacity and vascular function will be assessed 1 hour following oral ingestion of sildenafil (50 mg)
    Other Names:
    • Viagra
    • Revatio
  • Drug: Sub-Chronic (4 weeks) Sildenafil
    Exercise capacity and vascular function will be assessed 4 weeks following 20 mg three times per day (TID) of sildenafil for four weeks
    Other Names:
    • Viagra
    • Revatio
  • Drug: Placebo
    Sugar pill designed to mimic the sildenafil treatment
  • Experimental: Acute (1 hour) Sildenafil & Placebo
    In randomized order, on two separate days, exercise capacity and endothelial function will be determined 1 hour following a single dose of either sildenafil (50 mg) or placebo.
    • Drug: Acute (1 hour) Sildenafil
    • Drug: Placebo
  • Experimental: Sub Chronic (4 weeks) Sildenafil
    Following the acute study, patients will be instructed to take 20 mg of sildenafil, three times a day, for 4 weeks. Exercise capacity and endothelial function will be determined within 48 hours following the last dose.
    Intervention: Drug: Sub-Chronic (4 weeks) Sildenafil
Not Provided

*   Includes publications given by the data provider as well as publications identified by Identifier (NCT Number) in Medline.
Active, not recruiting
Same as current
December 2018
July 2018   (Final data collection date for primary outcome measure)

Inclusion Criteria.

  • Diagnosis of CF and healthy controls
  • Men and women (greater than 18 yrs. old)
  • Resting oxygen saturation (room air) greater than 90%
  • Forced expiratory volume (FEV1) percent predicted greater than 30%
  • Patients with or without CF related diabetes
  • Traditional CF-treatment medications
  • Ability to perform reliable/reproducible pulmonary function tests (PFT)
  • Clinically stable for 2 weeks (no exacerbations or need for antibiotic treatment within 2 weeks of testing or major change in medical status)

Exclusion Criteria.

  • Children less than 17 years old
  • Body mass less than 20 kg
  • A diagnosis of pulmonary arterial hypertension (PAH)
  • FEV1 less than 30% of predicted
  • Resting oxygen saturation (SpO2) less than 90%
  • Self-reported to be a smoker
  • Current use of any vaso-active medications
  • History of migraine headaches
  • Pregnant or nursing at the time of the investigation
  • A clinical diagnosis of cardiovascular disease, hypertension, or CF related diabetes
Sexes Eligible for Study: All
18 Years and older   (Adult, Older Adult)
Contact information is only displayed when the study is recruiting subjects
United States
R21DK100783 ( U.S. NIH Grant/Contract )
Not Provided
Plan to Share IPD: Yes
Ryan Harris, National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Augusta University
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Principal Investigator: Ryan Harris, Ph.D. Augusta University
Augusta University
June 2018

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP