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Phosphodiesterase type 5 (PDE5) inhibitor

Sildenafil for Exercise Intolerance in Cystic Fibrosis

Phase 2 & 3
Waitlist Available
Led By Jennifer Taylor-Cousar, MD, MSCS
Research Sponsored by National Jewish Health
Eligibility Criteria Checklist
Specific guidelines that determine who can or cannot participate in a clinical trial
Must have
Willingness to maintain chronic CF medication schedule (e.g. alternating month inhaled antibiotics)
Confirmed diagnosis of cystic fibrosis (CF) based on positive sweat chloride concentration ≥60 milliequivalents (mEq)/liter (by pilocarpine iontophoresis) and/or genotype with two identifiable disease-causing mutations consistent with CF, and accompanied by one or more clinical features consistent with the CF phenotype
Must not have
History of Priapism or known penile anatomical deformities
History of significant hepatic disease (aspartate transaminase or alanine transaminase > 3 times the upper limit of normal at screening, documented biliary cirrhosis, or portal hypertension)
Timeline
Screening 3 weeks
Treatment Varies
Follow Up change in fmd between weeks 1 and 12
Awards & highlights
Approved for 5 Other Conditions
All Individual Drugs Already Approved

Summary

This trial found that sildenafil may help people with CF who have exercise intolerance by improving blood flow.

Who is the study for?
This trial is for people over 9 years old with cystic fibrosis who have a certain level of lung function and are stable without recent infections. They must be able to perform spirometry tests, maintain their CF medication schedule, and not be pregnant or breastfeeding. Excluded are those with severe diseases, anatomical deformities, drug sensitivities, or taking certain medications.
What is being tested?
The study is testing whether sildenafil can improve exercise ability in individuals with cystic fibrosis by addressing vascular dysfunction. Participants will either receive the actual drug or a placebo capsule to compare outcomes.
What are the potential side effects?
Sildenafil may cause headaches, flushing, indigestion, vision changes like increased sensitivity to light or blurred vision; rare side effects include priapism (prolonged erection) and potential heart issues in predisposed individuals.

Eligibility Criteria

Inclusion Criteria

You may be eligible if you check “Yes” for the criteria below
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I am willing to follow a strict CF medication schedule.
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I have cystic fibrosis confirmed by a sweat test or genetic test.
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My lung function, measured by FEV1, is within the required range.

Exclusion Criteria

You may be eligible for the trial if you check “No” for criteria below:
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I have had priapism or have known deformities of the penis.
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I do not have a history of serious liver disease.
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I have had serious eye diseases like retinal problems.
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I have a severe blood disorder or a current INR greater than 2.0.
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I have a history of serious heart disease.
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I weigh less than 20 kilograms.
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I am 8 years old or younger.
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I have had a severe neurological condition, like a stroke.
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I have had severe kidney problems (creatinine >1.8 mg/dL).
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I cannot swallow pills.
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I have had an organ transplant.

Timeline

Screening ~ 3 weeks
Treatment ~ Varies
Follow Up ~change in fmd between weeks 1 and 12
This trial's timeline: 3 weeks for screening, Varies for treatment, and change in fmd between weeks 1 and 12 for reporting.

Treatment Details

Study Objectives

Study objectives can provide a clearer picture of what you can expect from a treatment.
Primary study objectives
6 Minute Walk Distance (6MWD)
Secondary study objectives
Cardiac strain
Cystic Fibrosis Questionnaire-Revised (CFQ-R) respiratory domain score
Flow-Mediated Dilation (FMD)
+1 more

Awards & Highlights

Approved for 5 Other Conditions
This treatment demonstrated efficacy for 5 other conditions.
All Individual Drugs Already Approved
Therapies where all constituent drugs have already been approved are likely to have better-understood side effect profiles.

Trial Design

2Treatment groups
Active Control
Placebo Group
Group I: SildenafilActive Control1 Intervention
active sildenafil 40 mg p.o. three times per day
Group II: Placebo ArmPlacebo Group1 Intervention
placebo three times per day

Find a Location

Who is running the clinical trial?

Cystic Fibrosis FoundationOTHER
197 Previous Clinical Trials
37,544 Total Patients Enrolled
190 Trials studying Cystic Fibrosis
34,647 Patients Enrolled for Cystic Fibrosis
Augusta UniversityOTHER
215 Previous Clinical Trials
85,664 Total Patients Enrolled
4 Trials studying Cystic Fibrosis
116 Patients Enrolled for Cystic Fibrosis
National Jewish HealthLead Sponsor
144 Previous Clinical Trials
317,348 Total Patients Enrolled
24 Trials studying Cystic Fibrosis
1,891 Patients Enrolled for Cystic Fibrosis
Jennifer Taylor-Cousar, MD, MSCSPrincipal Investigator - National Jewish Health
Duke University School Of Medicine (Medical School)
1 Previous Clinical Trials
5 Total Patients Enrolled
1 Trials studying Cystic Fibrosis
5 Patients Enrolled for Cystic Fibrosis

Media Library

Sildenafil (Phosphodiesterase type 5 (PDE5) inhibitor) Clinical Trial Eligibility Overview. Trial Name: NCT04039087 — Phase 2 & 3
Cystic Fibrosis Research Study Groups: Placebo Arm, Sildenafil
Cystic Fibrosis Clinical Trial 2023: Sildenafil Highlights & Side Effects. Trial Name: NCT04039087 — Phase 2 & 3
Sildenafil (Phosphodiesterase type 5 (PDE5) inhibitor) 2023 Treatment Timeline for Medical Study. Trial Name: NCT04039087 — Phase 2 & 3
~4 spots leftby Jan 2026
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