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Sildenafil Trial of Exercise Performance in Idiopathic Pulmonary Fibrosis

Sildenafil Trial of Exercise Performance in Idiopathic Pulmonary Fibrosis

Status
Completed
Phases
Phase 3
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT00517933
Acronym
STEP-IPF
Enrollment
180
Registered
2007-08-17
Start date
2007-08-31
Completion date
2009-10-31
Last updated
2015-06-24

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Hypertension, Pulmonary, Pulmonary Fibrosis

Keywords

Idiopathic Pulmonary Fibrosis, Pulmonary Hypertension

Brief summary

Idiopathic pulmonary fibrosis (IPF) is a chronic lung disease that affects an individual's ability to breathe. This study will evaluate the effectiveness of sildenafil, a medication that increases blood flow to the lungs, at improving breathing function, exercise capacity, and quality of life in people with advanced IPF.

Detailed description

IPF is a disease in which fibrous tissue clogs the lungs. This eventually damages air sacs in the lungs and leads to widespread and permanent scarring of lung tissue. Individuals with IPF may experience breathing difficulties, cough, chest pain, and a decreased exercise capacity. Pulmonary hypertension, which is high blood pressure in the arteries of the lungs, affects half of all people with IPF. The fibrous tissue that clogs the lungs also blocks blood from flowing through the lungs effectively, reducing the amount of oxygen in the lungs. The fibrous tissue also reduces the lungs' ability to use what oxygen is available. These factors can cause breathing difficulties and may eventually lead to heart disease. Sildenafil is a medication that can increase blood supply to the lungs and reduce the heart's workload. The purpose of this study is to evaluate the effectiveness of sildenafil at improving breathing function, exercise capacity, and quality of life in people with advanced IPF. This study will enroll people with advanced IPF. Participants will be randomly assigned to receive sildenafil or placebo three times a day for 12 weeks. Study visits will occur at baseline and Weeks 1, 6, and 12. At Week 12, participants will have the option to continue in the study for an additional 12 weeks. All participants who agree to continue in the study will receive sildenafil three times a day for the second 12 weeks. Study visits will occur at Weeks 13, 18, and 24. At all study visits, a physical exam and blood collection will occur. At selected visits, the following study procedures will occur: lung function testing; urine collection; a 6-minute walk test, which will measure the distance walked in a 6-minute period; and questionnaires to assess health status, breathing, and quality of life. Participants will record medication usage and symptoms in a daily diary. Study researchers will review medical records and the Social Security death index 5 years following the end of the study to determine the incidence of death among study participants.

Interventions

DRUGSildenafil Citrate

Sildenafil citrate (20mg 3 times a day \[TID\] orally for 12 weeks followed by 20mg TID open-label sildenafil for an additional 12 weeks)

OTHERPlacebo

Placebo (20mg TID orally for 12 weeks followed by 20mg open-label sildenafil for 12 weeks)

Sponsors

National Heart, Lung, and Blood Institute (NHLBI)
CollaboratorNIH
Pfizer
CollaboratorINDUSTRY
Duke University
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
TRIPLE (Subject, Investigator, Outcomes Assessor)

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* Clinical diagnosis of IPF * Diffusing capacity of the lung (DLCO) level less than 35% (adjusted for hemoglobin)

Exclusion criteria

* Current enrollment in another investigational study * Six-minute walk distance of less than 50 meters at screening or study entry * Difference of greater than 15% between the screening and study entry 6-minute walk distance * Acute or long-term impairment other than dyspnea (e.g., angina pectoris, intermittent claudication) that limits the ability to comply with the 6-minute walk test or other study requirements * Forced Expiratory Volume 1-second (FEV1)/forced vital capacity (FVC) ratio of less than 0.65 after bronchodilator use * Extent of emphysema greater than the extent of fibrotic change (e.g., honeycombing, reticular changes) on high-resolution computed tomography (HRCT) scan * Acute heart attack within the 6 months prior to study entry * Nitrate use * Hypersensitivity to sildenafil or any component of the formulation * Presence of aortic stenosis (AS) * Life-threatening arrhythmia within 1 month of study entry * Diabetes mellitus requiring insulin therapy * Second-degree or third-degree atrioventricular (AV) block on electrocardiogram * Severe chronic heart failure, defined by left ventricular ejection fraction (LVEF) of less than 25% * Presence of idiopathic hypertrophic subaortic stenosis (IHSS) * Hypotension (i.e., systolic blood pressure \[SBP\] less than 100 mm Hg or diastolic blood pressure \[DBP\] less than 50 mm Hg) * Uncontrolled systemic hypertension (i.e., SBP greater than 180 mm Hg or DBP greater than 100 mm Hg) * Known penile deformities or conditions (e.g., sickle cell anemia, multiple myeloma, leukemia) that may predispose participant to priapism * Aspartate aminotransferase (AST), serum glutamic pyruvic transaminase (SGPT), alanine aminotransferase (ALT), or serum glutamic oxaloacetic transaminase (SGOT) greater than three times the upper limit of normal range * Kidney impairment (i.e., creatinine clearance less than 30 mL/minute) * Current drug or alcohol dependence * Retinitis pigmentosa * History of vision loss * History of nonarteritic ischemic optic neuropathy * Recently initiated pulmonary rehabilitation within 30 days of study entry. Participants will be prohibited from starting pulmonary rehabilitation during the study. Participants who are currently undergoing maintenance pulmonary rehabilitation at study entry will be asked to maintain their levels of rehabilitation for the duration of the study. * Use of any investigational therapy as part of a clinical trial for any medical condition within 30 days of study entry * Start or change in dose of treatment for IPF investigational agent (e.g., interferon gamma-1b, pirfenidone, etanercept, N-acetylcysteine, any other investigational agent intended to treat IPF), corticosteroids, or cytotoxic agents within 30 days of study entry * Use of certain medications. More information about this criterion can be found in the study protocol. * Treatment for pulmonary hypertension with prostaglandins (e.g., epoprostenol, treprostinil), endothelin-1 antagonists (e.g., bosentan, sitaxsentan, ambrisentan), or any other phosphodiesterase inhibitor (e.g., tadalafil, vardenafil) within 30 days of study entry * Addition or discontinuation of calcium channel blockers, digitalis, diuretics, or vasodilators within 30 days of study entry (dosage must be stable for 7 days prior to study entry \[except for diuretics\]) * Currently on the waiting list for a lung transplant * Use of L-arginine supplements * Use of grapefruit juice or St. John's wort * Pregnant or breastfeeding * Resting saturation of peripheral oxygen (SpO2) (i.e., oxygen saturation measured using pulse oximetry) less than 92% with 6 liters of supplemental oxygen

Design outcomes

Primary

MeasureTime frameDescription
Change in 6-minute Walk Distance From Enrollment to Week 12 (≥ 20% Improvement)Measured at Week 12This is a binary score (1 or 0) with 1 being better than 0. All models adjust for baseline values of age, height, sex, white race, and DLCO. Values from models are estimated changes from baseline to 12 weeks (with 95% confidence intervals). The difference estimate is based on sildenafil - placebo.

Secondary

MeasureTime frameDescription
Estimated Change From Baseline to 12 Weeks in 6-minute Walk DistanceBaseline, week 12The 6MWT measures the distance that a participant can walk in a period of 6 minutes. All models adjust for baseline values of age, height, sex, white race, and DLCO. Values from models are estimated changes from baseline to 12 weeks (with 95% confidence intervals). The difference estimate is based on sildenafil - placebo.
Desaturation During 6-minute Walk Test (6MWT)Week 12The 6MWT was stopped when the pulse oximetry (SpO2) dropped to below 80% for six consecutive seconds. The estimates are based on the Kaplan-Meier event curves with minutes walked as the x-axis.
Change in DyspneaMeasured from enrollment to 12 weeks (phase I)The University of California at San Diego Shortness of Breath Questionnaire (SOBQ) uses a 6-point scale (0 = not at all to 5 = maximal or unable to do because of breathlessness) to rate 24 items. The final score ranges from 0 to 120 -- lower scores are better.
University of California at San Diego (UCSD) Shortness of Breath Questionnaire TotalBaseline, 6 weeks, 12 weeksThe University of California at San Diego Shortness of Breath Questionnaire (SOBQ) uses a 6-point scale (0 = not at all to 5 = maximal or unable to do because of breathlessness) to rate 24 items. The final score ranges from 0 to 120 -- lower scores are better. (Raw scores) Values adjusted for baseline values of age, height, sex, white race, and DLCO. Values from models are estimated changes from baseline to 12 weeks (with 95% confidence intervals). The difference estimate is based on sildenafil - placebo.
Change in Forced Vital Capacity (FVC) Adjusted ValuesBaseline, Week 12Change in FVC (liters) from baseline (time 0) to week 12 comparing the sildenafil and placebo groups. Values adjusted for baseline values of age, height, sex, white race, and DLCO. Values from models are estimated changes from baseline to 12 weeks (with 95% confidence intervals). The difference estimate is based on sildenafil - placebo.
Forced Vital Capacity (FVC)Baseline, Week 6, Week 12Raw scores of FVC (liters) from baseline (time 0) to week 6 and 12 comparing the sildenafil and placebo groups
Change in Diffusing Capacity of the Lung for Carbon Monoxide (DLCO) Adjusted ValuesBaseline, Week 12Change in DLCO (% predicted) measured at baseline (time 0), and week 12 comparing the sildenafil and placebo groups. All models adjust for baseline values of age, height, sex, white race, and DLCO. Values from models are estimated changes from baseline to 12 weeks (with 95% confidence intervals). The difference estimate is based on sildenafil - placebo.
Diffusing Capacity of the Lung for Carbon Monoxide (DLCO)Baseline, Week 6, Week 12Raw scores of DLCO (% predicted) measured at baseline (time 0), week 6, and week 12 comparing the sildenafil and placebo groups
Change in Borg Dyspnea Index (BDI) After 6 Minute Walk Test (Adjusted Values)Baseline, 12 weekThe BDI was calculated by using a 10-point scale (0 = None, 10 = Maximum) and indicates the degree of breathlessness after completion of the 6-minute walk test. Values adjusted for baseline values of age, height, sex, white race, and DLCO. Values from models are estimated changes from baseline to 12 weeks (with 95% confidence intervals). The difference estimate is based on sildenafil - placebo.
Borg Dyspnea Index (BDI) After 6 Minute Walk Test (Raw Scores)Baseline, 6 week, 12 weekThe BDI was calculated by using a 10-point scale (0 = None, 10 = Maximum) and indicates the degree of breathlessness after completion of the 6-minute walk test.
Change in St. George's Respiratory Questionnaire (Total Score) (Adjusted Values)Baseline, 12 weekThe St. George's Respiratory Questionnaire asks patients how breathing problems impair their life and is scored from 0 (no impairment) to 100 (maximum impairment.) Values adjusted for baseline values of age, height, sex, white race, and DLCO. Values from models are estimated changes from baseline to 12 weeks (with 95% confidence intervals). The difference estimate is based on sildenafil - placebo.
St. George's Respiratory Questionnaire (Total Score)Baseline, 6 weeks, 12 weeksMean raw scores of the St. George's Respiratory Questionnaire. The St. George's Respiratory Questionnaire asks patients how breathing problems impair their life and is scored from 0 (no impairment) to 100 (maximum impairment.)
Change in St. George's Respiratory Questionnaire (Symptoms Score) Adjusted ValueBaseline, 12 weeksThe St. George's Respiratory Questionnaire asks patients how breathing problems impair their life and is scored from 0 (no impairment) to 100 (maximum impairment). Values adjusted for baseline values of age, height, sex, white race, and DLCO. Values from models are estimated changes from baseline to 12 weeks (with 95% confidence intervals). The difference estimate is based on sildenafil - placebo.
St. George's Respiratory Questionnaire (Symptoms Score)Baseline, 6 weeks, 12 weeksThe St. George's Respiratory Questionnaire asks patients how breathing problems impair their life and is scored from 0 (no impairment) to 100 (maximum impairment). Mean raw scores of the St. George's Respiratory Questionnaire. Mean raw scores of the St. George's Respiratory Questionnaire.
6-minute Walk Distance (6MWT)Baseline, 6 week, 12 weekThe 6MWT measures the distance that a participant can walk in a period of 6 minutes.
St. George's Respiratory Questionnaire (Activity Score)Baseline, 6 weeks, 12 weeksThe St. George's Respiratory Questionnaire asks patients how breathing problems impair their life and is scored from 0 (no impairment) to 100 (maximum impairment). Mean raw scores of the St. George's Respiratory Questionnaire.
Change in St. George's Respiratory Questionnaire (Impacts Score) Adjusted ValueBaseline, 12 weeksThe St. George's Respiratory Questionnaire asks patients how breathing problems impair their life and is scored from 0 (no impairment) to 100 (maximum impairment). Values adjusted for baseline values of age, height, sex, white race, and DLCO. Values from models are estimated changes from baseline to 12 weeks (with 95% confidence intervals). The difference estimate is based on sildenafil - placebo.
St. George's Respiratory Questionnaire (Impacts Score)Baseline, 6 weeks, 12 weeksThe St. George's Respiratory Questionnaire asks patients how breathing problems impair their life and is scored from 0 (no impairment) to 100 (maximum impairment). Mean raw scores of the St. George's Respiratory Questionnaire.
Change in ICECAP-O Adjusted ValueBaseline, 12 weeksThe ICEpop CAPability measure for Older people (ICECAP-O) is a measure of capability in older people for use in economic evaluation. The values of ICECAP-O range from 0 (worst) to 1 (best). Values adjusted for baseline values of age, height, sex, white race, and DLCO. Values from models are estimated changes from baseline to 12 weeks (with 95% confidence intervals). The difference estimate is based on sildenafil - placebo.
ICECAP-OBaseline, 6 weeks, 12 weeksThe ICEpop CAPability measure for Older people (ICECAP-O) is a measure of capability in older people for use in economic evaluation. The values of ICECAP-O range from 0 (worst) to 1 (best). Mean raw scores of ICECAP-O.
Change in EuroQOL Thermometer (Adjusted Value)Baseline, 12 weeksThe thermometer score ranges from 0 (worst imaginable health state) to 100 (best imaginable health state). Higher scores indicate a better health state. Values adjusted for baseline values of age, height, sex, white race, and DLCO. Values from models are estimated changes from baseline to 12 weeks (with 95% confidence intervals). The difference estimate is based on sildenafil - placebo.
EuroQOL ThermometerBaseline, 6 weeks, 12 weeksThe thermometer score ranges from 0 (worst imaginable health state) to 100 (best imaginable health state). Higher scores indicate a better health state. Mean raw scores of EuroQOL Thermometer.
Change in EuroQOL (EQ-5D) Utility - Adjusted ValueBaseline, 12 weeksEQ-5D: participant rated questionnaire to assess health-related quality of life in terms of a single utility score. Health State Profile component assesses level of current health for 5 domains: mobility, self-care, usual activities, pain and discomfort, and anxiety and depression; 1 indicates better health state (no problems); 3 indicates worst health state (eg, confined to bed). Scoring formula developed by EuroQol Group assigns a utility value for each domain in the profile. Score is transformed and results in total score range -0.594 to 1.000; higher score indicates better health state. Values adjusted for baseline values of age, height, sex, white race, and DLCO. Values from models are estimated changes from baseline to 12 weeks (with 95% confidence intervals). The difference estimate is based on sildenafil - placebo.
EuroQOL (EQ-5D) UtilityBaseline, 6 weeks, 12 weeksEQ-5D: participant rated questionnaire to assess health-related quality of life in terms of a single utility score. Health State Profile component assesses level of current health for 5 domains: mobility, self-care, usual activities, pain and discomfort, and anxiety and depression; 1 indicates better health state (no problems); 3 indicates worst health state (eg, confined to bed). Scoring formula developed by EuroQol Group assigns a utility value for each domain in the profile. Score is transformed and results in total score range -0.594 to 1.000; higher score indicates better health state. Mean raw scores of EuroQOL Utility.
Change in Short Form Health Survey (SF36) General Health - Adjusted ValueBaseline, 12 weeksThe SF36 measures functional health and well-being scores on eight scales that correlate with two aggregate scores. Each score ranges from 0 to 100, with a higher score indicating better function. Values adjusted for baseline values of age, height, sex, white race, and DLCO. Values from models are estimated changes from baseline to 12 weeks (with 95% confidence intervals). The difference estimate is based on sildenafil - placebo.
Short Form Health Survey (SF36) General HealthBaseline, 6 weeks, 12 weeksThe SF36 measures functional health and well-being scores on eight scales that correlate with two aggregate scores. Each score ranges from 0 to 100, with a higher score indicating better function. Mean raw scores of SF36 General Health
Change in SF36 Aggregate Physical (Adjusted Value)Baseline, 12 weeksThe SF36 measures functional health and well-being scores on eight scales that correlate with two aggregate scores. Each score ranges from 0 to 100, with a higher score indicating better function. Values adjusted for baseline values of age, height, sex, white race, and DLCO. Values from models are estimated changes from baseline to 12 weeks (with 95% confidence intervals). The difference estimate is based on sildenafil - placebo.
Short Form Health Survey (SF36) Aggregate PhysicalBaseline, 6 weeks, 12 weeksThe SF36 measures functional health and well-being scores on eight scales that correlate with two aggregate scores. Each score ranges from 0 to 100, with a higher score indicating better function. Mean raw scores of SF36 Aggregate Physical.
Change in St. George's Respiratory Questionnaire (Activity Score) Adjusted ValueBaseline, 12 weeksThe St. George's Respiratory Questionnaire asks patients how breathing problems impair their life and is scored from 0 (no impairment) to 100 (maximum impairment). Values adjusted for baseline values of age, height, sex, white race, and DLCO. Values from models are estimated changes from baseline to 12 weeks (with 95% confidence intervals). The difference estimate is based on sildenafil - placebo.

Countries

United States

Participant flow

Participants by arm

ArmCount
Sildenafil
20 mg of oral sildenafil 3 times per day for 12 weeks, followed by 20 mg oral sildenafil 3 times per day for 12 weeks
89
Placebo
20 mg of placebo 3 times per day for 12 weeks, followed by 20 mg open-label sildenafil 3 times per day for 12 weeks
91
Total180

Withdrawals & dropouts

PeriodReasonFG000FG001
Period 1Adverse Event44
Period 1Death21
Period 1Lost to Follow-up20
Period 1Underwent lung transplant01
Period 2Adverse Event24
Period 2Death24
Period 2Physician Decision10
Period 2Underwent lung transplant02
Period 2Withdrawal by Subject13

Baseline characteristics

CharacteristicSildenafilPlaceboTotal
Age, Continuous69.8 years
STANDARD_DEVIATION 8.7
68.2 years
STANDARD_DEVIATION 9.3
69.0 years
STANDARD_DEVIATION 8.9
Region of Enrollment
United States
89 participants91 participants180 participants
Sex: Female, Male
Female
14 Participants16 Participants30 Participants
Sex: Female, Male
Male
75 Participants75 Participants150 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
deaths
Total, all-cause mortality
— / —— / —
other
Total, other adverse events
72 / 8962 / 91
serious
Total, serious adverse events
13 / 8915 / 91

Outcome results

Primary

Change in 6-minute Walk Distance From Enrollment to Week 12 (≥ 20% Improvement)

This is a binary score (1 or 0) with 1 being better than 0. All models adjust for baseline values of age, height, sex, white race, and DLCO. Values from models are estimated changes from baseline to 12 weeks (with 95% confidence intervals). The difference estimate is based on sildenafil - placebo.

Time frame: Measured at Week 12

ArmMeasureValue (NUMBER)
SildenafilChange in 6-minute Walk Distance From Enrollment to Week 12 (≥ 20% Improvement)9 participants
PlaceboChange in 6-minute Walk Distance From Enrollment to Week 12 (≥ 20% Improvement)6 participants
p-value: 0.39Chi-squared
Secondary

6-minute Walk Distance (6MWT)

The 6MWT measures the distance that a participant can walk in a period of 6 minutes.

Time frame: Baseline, 6 week, 12 week

ArmMeasureGroupValue (MEAN)Dispersion
Sildenafil6-minute Walk Distance (6MWT)1st baseline246.93 metersStandard Deviation 99.11
Sildenafil6-minute Walk Distance (6MWT)2nd baseline246.39 metersStandard Deviation 103.4
Sildenafil6-minute Walk Distance (6MWT)6 week237.29 metersStandard Deviation 121.48
Sildenafil6-minute Walk Distance (6MWT)12 week239.09 metersStandard Deviation 126.39
Placebo6-minute Walk Distance (6MWT)12 week249.48 metersStandard Deviation 138.46
Placebo6-minute Walk Distance (6MWT)1st baseline267.71 metersStandard Deviation 127.75
Placebo6-minute Walk Distance (6MWT)6 week257.55 metersStandard Deviation 139.44
Placebo6-minute Walk Distance (6MWT)2nd baseline269.55 metersStandard Deviation 129.83
Secondary

Borg Dyspnea Index (BDI) After 6 Minute Walk Test (Raw Scores)

The BDI was calculated by using a 10-point scale (0 = None, 10 = Maximum) and indicates the degree of breathlessness after completion of the 6-minute walk test.

Time frame: Baseline, 6 week, 12 week

ArmMeasureGroupValue (MEAN)Dispersion
SildenafilBorg Dyspnea Index (BDI) After 6 Minute Walk Test (Raw Scores)6 week3.53 units on a scaleStandard Deviation 1.91
SildenafilBorg Dyspnea Index (BDI) After 6 Minute Walk Test (Raw Scores)Change from Baseline to 6 week-0.23 units on a scaleStandard Deviation 1.37
SildenafilBorg Dyspnea Index (BDI) After 6 Minute Walk Test (Raw Scores)12 week3.76 units on a scaleStandard Deviation 2.22
SildenafilBorg Dyspnea Index (BDI) After 6 Minute Walk Test (Raw Scores)Change from Baseline to 12 week0.09 units on a scaleStandard Deviation 1.62
SildenafilBorg Dyspnea Index (BDI) After 6 Minute Walk Test (Raw Scores)Baseline3.72 units on a scaleStandard Deviation 1.79
PlaceboBorg Dyspnea Index (BDI) After 6 Minute Walk Test (Raw Scores)Change from Baseline to 12 week0.39 units on a scaleStandard Deviation 1.7
PlaceboBorg Dyspnea Index (BDI) After 6 Minute Walk Test (Raw Scores)Baseline3.23 units on a scaleStandard Deviation 1.8
PlaceboBorg Dyspnea Index (BDI) After 6 Minute Walk Test (Raw Scores)6 week3.42 units on a scaleStandard Deviation 1.79
PlaceboBorg Dyspnea Index (BDI) After 6 Minute Walk Test (Raw Scores)12 week3.49 units on a scaleStandard Deviation 1.61
PlaceboBorg Dyspnea Index (BDI) After 6 Minute Walk Test (Raw Scores)Change from Baseline to 6 week0.37 units on a scaleStandard Deviation 1.42
Secondary

Change in Borg Dyspnea Index (BDI) After 6 Minute Walk Test (Adjusted Values)

The BDI was calculated by using a 10-point scale (0 = None, 10 = Maximum) and indicates the degree of breathlessness after completion of the 6-minute walk test. Values adjusted for baseline values of age, height, sex, white race, and DLCO. Values from models are estimated changes from baseline to 12 weeks (with 95% confidence intervals). The difference estimate is based on sildenafil - placebo.

Time frame: Baseline, 12 week

ArmMeasureValue (MEAN)
SildenafilChange in Borg Dyspnea Index (BDI) After 6 Minute Walk Test (Adjusted Values)0.04 units on a scale
PlaceboChange in Borg Dyspnea Index (BDI) After 6 Minute Walk Test (Adjusted Values)0.37 units on a scale
p-value: 0.1695% CI: [-0.81, 0.14]Regression, Linear
Secondary

Change in Diffusing Capacity of the Lung for Carbon Monoxide (DLCO) Adjusted Values

Change in DLCO (% predicted) measured at baseline (time 0), and week 12 comparing the sildenafil and placebo groups. All models adjust for baseline values of age, height, sex, white race, and DLCO. Values from models are estimated changes from baseline to 12 weeks (with 95% confidence intervals). The difference estimate is based on sildenafil - placebo.

Time frame: Baseline, Week 12

Population: ITT

ArmMeasureValue (LEAST_SQUARES_MEAN)
SildenafilChange in Diffusing Capacity of the Lung for Carbon Monoxide (DLCO) Adjusted Values-0.30 percentage of predicted (DLCO)
PlaceboChange in Diffusing Capacity of the Lung for Carbon Monoxide (DLCO) Adjusted Values-1.9 percentage of predicted (DLCO)
p-value: 0.0495% CI: [0.1, 3]Mixed Models Analysis
Secondary

Change in Dyspnea

The University of California at San Diego Shortness of Breath Questionnaire (SOBQ) uses a 6-point scale (0 = not at all to 5 = maximal or unable to do because of breathlessness) to rate 24 items. The final score ranges from 0 to 120 -- lower scores are better.

Time frame: Measured from enrollment to 12 weeks (phase I)

ArmMeasureValue (MEAN)
SildenafilChange in Dyspnea0.22 units on a scale
PlaceboChange in Dyspnea6.81 units on a scale
p-value: 0.00695% CI: [-11.25, -1.92]Mixed Models Analysis
Secondary

Change in EuroQOL (EQ-5D) Utility - Adjusted Value

EQ-5D: participant rated questionnaire to assess health-related quality of life in terms of a single utility score. Health State Profile component assesses level of current health for 5 domains: mobility, self-care, usual activities, pain and discomfort, and anxiety and depression; 1 indicates better health state (no problems); 3 indicates worst health state (eg, confined to bed). Scoring formula developed by EuroQol Group assigns a utility value for each domain in the profile. Score is transformed and results in total score range -0.594 to 1.000; higher score indicates better health state. Values adjusted for baseline values of age, height, sex, white race, and DLCO. Values from models are estimated changes from baseline to 12 weeks (with 95% confidence intervals). The difference estimate is based on sildenafil - placebo.

Time frame: Baseline, 12 weeks

ArmMeasureValue (MEAN)
SildenafilChange in EuroQOL (EQ-5D) Utility - Adjusted Value-0.01 units on a scale
PlaceboChange in EuroQOL (EQ-5D) Utility - Adjusted Value-0.03 units on a scale
Secondary

Change in EuroQOL Thermometer (Adjusted Value)

The thermometer score ranges from 0 (worst imaginable health state) to 100 (best imaginable health state). Higher scores indicate a better health state. Values adjusted for baseline values of age, height, sex, white race, and DLCO. Values from models are estimated changes from baseline to 12 weeks (with 95% confidence intervals). The difference estimate is based on sildenafil - placebo.

Time frame: Baseline, 12 weeks

ArmMeasureValue (MEAN)
SildenafilChange in EuroQOL Thermometer (Adjusted Value)0.5 units on a scale
PlaceboChange in EuroQOL Thermometer (Adjusted Value)-1.8 units on a scale
p-value: 0.3795% CI: [-2.8, 7.3]Regression, Linear
Secondary

Change in Forced Vital Capacity (FVC) Adjusted Values

Change in FVC (liters) from baseline (time 0) to week 12 comparing the sildenafil and placebo groups. Values adjusted for baseline values of age, height, sex, white race, and DLCO. Values from models are estimated changes from baseline to 12 weeks (with 95% confidence intervals). The difference estimate is based on sildenafil - placebo.

Time frame: Baseline, Week 12

Population: ITT

ArmMeasureValue (LEAST_SQUARES_MEAN)
SildenafilChange in Forced Vital Capacity (FVC) Adjusted Values-0.04 liters
PlaceboChange in Forced Vital Capacity (FVC) Adjusted Values-0.05 liters
p-value: 0.795% CI: [-0.05, 0.07]Mixed Models Analysis
Secondary

Change in ICECAP-O Adjusted Value

The ICEpop CAPability measure for Older people (ICECAP-O) is a measure of capability in older people for use in economic evaluation. The values of ICECAP-O range from 0 (worst) to 1 (best). Values adjusted for baseline values of age, height, sex, white race, and DLCO. Values from models are estimated changes from baseline to 12 weeks (with 95% confidence intervals). The difference estimate is based on sildenafil - placebo.

Time frame: Baseline, 12 weeks

ArmMeasureValue (MEAN)
SildenafilChange in ICECAP-O Adjusted Value0.00 units on a scale
PlaceboChange in ICECAP-O Adjusted Value-0.02 units on a scale
p-value: 0.1895% CI: [-0.01, 0.06]Regression, Linear
Secondary

Change in SF36 Aggregate Physical (Adjusted Value)

The SF36 measures functional health and well-being scores on eight scales that correlate with two aggregate scores. Each score ranges from 0 to 100, with a higher score indicating better function. Values adjusted for baseline values of age, height, sex, white race, and DLCO. Values from models are estimated changes from baseline to 12 weeks (with 95% confidence intervals). The difference estimate is based on sildenafil - placebo.

Time frame: Baseline, 12 weeks

ArmMeasureValue (MEAN)
SildenafilChange in SF36 Aggregate Physical (Adjusted Value)-0.5 units on a scale
PlaceboChange in SF36 Aggregate Physical (Adjusted Value)-0.4 units on a scale
p-value: 0.8695% CI: [-2.1, 1.7]Regression, Linear
Secondary

Change in Short Form Health Survey (SF36) General Health - Adjusted Value

The SF36 measures functional health and well-being scores on eight scales that correlate with two aggregate scores. Each score ranges from 0 to 100, with a higher score indicating better function. Values adjusted for baseline values of age, height, sex, white race, and DLCO. Values from models are estimated changes from baseline to 12 weeks (with 95% confidence intervals). The difference estimate is based on sildenafil - placebo.

Time frame: Baseline, 12 weeks

ArmMeasureValue (MEAN)
SildenafilChange in Short Form Health Survey (SF36) General Health - Adjusted Value-1.0 units on a scale
PlaceboChange in Short Form Health Survey (SF36) General Health - Adjusted Value-3.9 units on a scale
p-value: 0.00895% CI: [0.8, 5]Regression, Linear
Secondary

Change in St. George's Respiratory Questionnaire (Activity Score) Adjusted Value

The St. George's Respiratory Questionnaire asks patients how breathing problems impair their life and is scored from 0 (no impairment) to 100 (maximum impairment). Values adjusted for baseline values of age, height, sex, white race, and DLCO. Values from models are estimated changes from baseline to 12 weeks (with 95% confidence intervals). The difference estimate is based on sildenafil - placebo.

Time frame: Baseline, 12 weeks

ArmMeasureValue (MEAN)
SildenafilChange in St. George's Respiratory Questionnaire (Activity Score) Adjusted Value-1.2 units on a scale
PlaceboChange in St. George's Respiratory Questionnaire (Activity Score) Adjusted Value2.5 units on a scale
p-value: 0.0495% CI: [-7.2, -0.1]Regression, Linear
Secondary

Change in St. George's Respiratory Questionnaire (Impacts Score) Adjusted Value

The St. George's Respiratory Questionnaire asks patients how breathing problems impair their life and is scored from 0 (no impairment) to 100 (maximum impairment). Values adjusted for baseline values of age, height, sex, white race, and DLCO. Values from models are estimated changes from baseline to 12 weeks (with 95% confidence intervals). The difference estimate is based on sildenafil - placebo.

Time frame: Baseline, 12 weeks

ArmMeasureValue (MEAN)
SildenafilChange in St. George's Respiratory Questionnaire (Impacts Score) Adjusted Value-0.9 units on a scale
PlaceboChange in St. George's Respiratory Questionnaire (Impacts Score) Adjusted Value2.8 units on a scale
p-value: 0.0795% CI: [-7.8, 0.4]Regression, Logistic
Secondary

Change in St. George's Respiratory Questionnaire (Symptoms Score) Adjusted Value

The St. George's Respiratory Questionnaire asks patients how breathing problems impair their life and is scored from 0 (no impairment) to 100 (maximum impairment). Values adjusted for baseline values of age, height, sex, white race, and DLCO. Values from models are estimated changes from baseline to 12 weeks (with 95% confidence intervals). The difference estimate is based on sildenafil - placebo.

Time frame: Baseline, 12 weeks

ArmMeasureValue (MEAN)
SildenafilChange in St. George's Respiratory Questionnaire (Symptoms Score) Adjusted Value-3.6 units on a scale
PlaceboChange in St. George's Respiratory Questionnaire (Symptoms Score) Adjusted Value2.2 units on a scale
p-value: 0.0295% CI: [-10.6, -0.9]Regression, Linear
Secondary

Change in St. George's Respiratory Questionnaire (Total Score) (Adjusted Values)

The St. George's Respiratory Questionnaire asks patients how breathing problems impair their life and is scored from 0 (no impairment) to 100 (maximum impairment.) Values adjusted for baseline values of age, height, sex, white race, and DLCO. Values from models are estimated changes from baseline to 12 weeks (with 95% confidence intervals). The difference estimate is based on sildenafil - placebo.

Time frame: Baseline, 12 week

ArmMeasureValue (MEAN)
SildenafilChange in St. George's Respiratory Questionnaire (Total Score) (Adjusted Values)-1.6 units on a scale
PlaceboChange in St. George's Respiratory Questionnaire (Total Score) (Adjusted Values)2.5 units on a scale
p-value: 0.0195% CI: [-7.3, -0.9]Regression, Linear
Secondary

Desaturation During 6-minute Walk Test (6MWT)

The 6MWT was stopped when the pulse oximetry (SpO2) dropped to below 80% for six consecutive seconds. The estimates are based on the Kaplan-Meier event curves with minutes walked as the x-axis.

Time frame: Week 12

Population: ITT population

ArmMeasureValue (NUMBER)
SildenafilDesaturation During 6-minute Walk Test (6MWT)83.6 percentage of participants
PlaceboDesaturation During 6-minute Walk Test (6MWT)75.3 percentage of participants
p-value: 0.41Log Rank
Secondary

Diffusing Capacity of the Lung for Carbon Monoxide (DLCO)

Raw scores of DLCO (% predicted) measured at baseline (time 0), week 6, and week 12 comparing the sildenafil and placebo groups

Time frame: Baseline, Week 6, Week 12

Population: ITT

ArmMeasureGroupValue (MEAN)Dispersion
SildenafilDiffusing Capacity of the Lung for Carbon Monoxide (DLCO)Week 626.00 percentage of predicted (DLCO)Standard Deviation 7.05
SildenafilDiffusing Capacity of the Lung for Carbon Monoxide (DLCO)Change from baseline to 6 weeks-0.07 percentage of predicted (DLCO)Standard Deviation 4.35
SildenafilDiffusing Capacity of the Lung for Carbon Monoxide (DLCO)Week 1225.66 percentage of predicted (DLCO)Standard Deviation 6.79
SildenafilDiffusing Capacity of the Lung for Carbon Monoxide (DLCO)Change from baseline to 12 weeks-0.33 percentage of predicted (DLCO)Standard Deviation 4.58
SildenafilDiffusing Capacity of the Lung for Carbon Monoxide (DLCO)Baseline25.81 percentage of predicted (DLCO)Standard Deviation 6.03
PlaceboDiffusing Capacity of the Lung for Carbon Monoxide (DLCO)Change from baseline to 12 weeks-1.78 percentage of predicted (DLCO)Standard Deviation 6.32
PlaceboDiffusing Capacity of the Lung for Carbon Monoxide (DLCO)Baseline26.73 percentage of predicted (DLCO)Standard Deviation 6.16
PlaceboDiffusing Capacity of the Lung for Carbon Monoxide (DLCO)Week 626.11 percentage of predicted (DLCO)Standard Deviation 6.28
PlaceboDiffusing Capacity of the Lung for Carbon Monoxide (DLCO)Week 1225.38 percentage of predicted (DLCO)Standard Deviation 7.43
PlaceboDiffusing Capacity of the Lung for Carbon Monoxide (DLCO)Change from baseline to 6 weeks-1.15 percentage of predicted (DLCO)Standard Deviation 4.59
Secondary

Estimated Change From Baseline to 12 Weeks in 6-minute Walk Distance

The 6MWT measures the distance that a participant can walk in a period of 6 minutes. All models adjust for baseline values of age, height, sex, white race, and DLCO. Values from models are estimated changes from baseline to 12 weeks (with 95% confidence intervals). The difference estimate is based on sildenafil - placebo.

Time frame: Baseline, week 12

ArmMeasureValue (MEAN)
SildenafilEstimated Change From Baseline to 12 Weeks in 6-minute Walk Distance-28.5 meters
PlaceboEstimated Change From Baseline to 12 Weeks in 6-minute Walk Distance-45.2 meters
p-value: 0.1195% CI: [-3.9, 37.3]Regression, Linear
Secondary

EuroQOL (EQ-5D) Utility

EQ-5D: participant rated questionnaire to assess health-related quality of life in terms of a single utility score. Health State Profile component assesses level of current health for 5 domains: mobility, self-care, usual activities, pain and discomfort, and anxiety and depression; 1 indicates better health state (no problems); 3 indicates worst health state (eg, confined to bed). Scoring formula developed by EuroQol Group assigns a utility value for each domain in the profile. Score is transformed and results in total score range -0.594 to 1.000; higher score indicates better health state. Mean raw scores of EuroQOL Utility.

Time frame: Baseline, 6 weeks, 12 weeks

ArmMeasureGroupValue (MEAN)Dispersion
SildenafilEuroQOL (EQ-5D) Utility6 week0.75 units on a scaleStandard Deviation 0.23
SildenafilEuroQOL (EQ-5D) UtilityChange from Baseline to 6 weeks0.04 units on a scaleStandard Deviation 0.18
SildenafilEuroQOL (EQ-5D) UtilityBaseline0.71 units on a scaleStandard Deviation 0.24
SildenafilEuroQOL (EQ-5D) UtilityChange from Baseline to 12 weeks-0.01 units on a scaleStandard Deviation 0.23
SildenafilEuroQOL (EQ-5D) Utility12 Week0.70 units on a scaleStandard Deviation 0.26
PlaceboEuroQOL (EQ-5D) UtilityChange from Baseline to 12 weeks-0.03 units on a scaleStandard Deviation 0.19
PlaceboEuroQOL (EQ-5D) UtilityBaseline0.74 units on a scaleStandard Deviation 0.19
PlaceboEuroQOL (EQ-5D) Utility6 week0.71 units on a scaleStandard Deviation 0.25
PlaceboEuroQOL (EQ-5D) Utility12 Week0.72 units on a scaleStandard Deviation 0.21
PlaceboEuroQOL (EQ-5D) UtilityChange from Baseline to 6 weeks-0.02 units on a scaleStandard Deviation 0.24
Secondary

EuroQOL Thermometer

The thermometer score ranges from 0 (worst imaginable health state) to 100 (best imaginable health state). Higher scores indicate a better health state. Mean raw scores of EuroQOL Thermometer.

Time frame: Baseline, 6 weeks, 12 weeks

ArmMeasureGroupValue (MEAN)Dispersion
SildenafilEuroQOL Thermometer6 week69.47 units on a scaleStandard Deviation 16.92
SildenafilEuroQOL ThermometerChange from Baseline to 6 weeks2.51 units on a scaleStandard Deviation 15.32
SildenafilEuroQOL Thermometer12 Week66.96 units on a scaleStandard Deviation 16.45
SildenafilEuroQOL ThermometerChange from Baseline to 12 weeks0.49 units on a scaleStandard Deviation 17.28
SildenafilEuroQOL ThermometerBaseline66.49 units on a scaleStandard Deviation 17.45
PlaceboEuroQOL ThermometerChange from Baseline to 12 weeks-2.12 units on a scaleStandard Deviation 19.08
PlaceboEuroQOL ThermometerBaseline67.66 units on a scaleStandard Deviation 16.98
PlaceboEuroQOL Thermometer6 week67.09 units on a scaleStandard Deviation 19.65
PlaceboEuroQOL Thermometer12 Week67.05 units on a scaleStandard Deviation 16.37
PlaceboEuroQOL ThermometerChange from Baseline to 6 weeks-1.40 units on a scaleStandard Deviation 17.23
Secondary

Forced Vital Capacity (FVC)

Raw scores of FVC (liters) from baseline (time 0) to week 6 and 12 comparing the sildenafil and placebo groups

Time frame: Baseline, Week 6, Week 12

Population: ITT

ArmMeasureGroupValue (MEAN)Dispersion
SildenafilForced Vital Capacity (FVC)Week 62.25 litersStandard Deviation 0.72
SildenafilForced Vital Capacity (FVC)Change from baseline to 6 weeks-0.03 litersStandard Deviation 0.21
SildenafilForced Vital Capacity (FVC)Week 122.22 litersStandard Deviation 0.75
SildenafilForced Vital Capacity (FVC)Change from baseline to 12 weeks-0.04 litersStandard Deviation 0.23
SildenafilForced Vital Capacity (FVC)Baseline2.25 litersStandard Deviation 0.7
PlaceboForced Vital Capacity (FVC)Change from baseline to 12 weeks-0.05 litersStandard Deviation 0.2
PlaceboForced Vital Capacity (FVC)Baseline2.42 litersStandard Deviation 0.75
PlaceboForced Vital Capacity (FVC)Week 62.40 litersStandard Deviation 0.74
PlaceboForced Vital Capacity (FVC)Week 122.36 litersStandard Deviation 0.78
PlaceboForced Vital Capacity (FVC)Change from baseline to 6 weeks-0.03 litersStandard Deviation 0.15
Secondary

ICECAP-O

The ICEpop CAPability measure for Older people (ICECAP-O) is a measure of capability in older people for use in economic evaluation. The values of ICECAP-O range from 0 (worst) to 1 (best). Mean raw scores of ICECAP-O.

Time frame: Baseline, 6 weeks, 12 weeks

ArmMeasureGroupValue (MEAN)Dispersion
SildenafilICECAP-OChange from Baseline to 6 weeks0.02 units on a scaleStandard Deviation 0.12
SildenafilICECAP-OBaseline0.79 units on a scaleStandard Deviation 0.14
SildenafilICECAP-OChange from Baseline to 12 weeks0.00 units on a scaleStandard Deviation 0.11
SildenafilICECAP-O6 week0.80 units on a scaleStandard Deviation 0.16
SildenafilICECAP-O12 Week0.79 units on a scaleStandard Deviation 0.14
PlaceboICECAP-O6 week0.76 units on a scaleStandard Deviation 0.17
PlaceboICECAP-O12 Week0.81 units on a scaleStandard Deviation 0.14
PlaceboICECAP-OChange from Baseline to 6 weeks-0.05 units on a scaleStandard Deviation 0.12
PlaceboICECAP-OChange from Baseline to 12 weeks-0.02 units on a scaleStandard Deviation 0.1
PlaceboICECAP-OBaseline0.81 units on a scaleStandard Deviation 0.13
Secondary

Short Form Health Survey (SF36) Aggregate Physical

The SF36 measures functional health and well-being scores on eight scales that correlate with two aggregate scores. Each score ranges from 0 to 100, with a higher score indicating better function. Mean raw scores of SF36 Aggregate Physical.

Time frame: Baseline, 6 weeks, 12 weeks

ArmMeasureGroupValue (MEAN)Dispersion
SildenafilShort Form Health Survey (SF36) Aggregate Physical6 week-1.70 units on a scaleStandard Deviation 0.99
SildenafilShort Form Health Survey (SF36) Aggregate PhysicalChange from Baseline to week 6-0.06 units on a scaleStandard Deviation 0.52
SildenafilShort Form Health Survey (SF36) Aggregate PhysicalBaseline-1.68 units on a scaleStandard Deviation 0.92
SildenafilShort Form Health Survey (SF36) Aggregate PhysicalChange from Baseline to week 12-0.05 units on a scaleStandard Deviation 0.56
SildenafilShort Form Health Survey (SF36) Aggregate Physical12 Week-1.71 units on a scaleStandard Deviation 0.86
PlaceboShort Form Health Survey (SF36) Aggregate PhysicalChange from Baseline to week 12-0.05 units on a scaleStandard Deviation 0.63
PlaceboShort Form Health Survey (SF36) Aggregate PhysicalBaseline-1.52 units on a scaleStandard Deviation 0.87
PlaceboShort Form Health Survey (SF36) Aggregate Physical6 week-1.58 units on a scaleStandard Deviation 0.91
PlaceboShort Form Health Survey (SF36) Aggregate Physical12 Week-1.51 units on a scaleStandard Deviation 0.89
PlaceboShort Form Health Survey (SF36) Aggregate PhysicalChange from Baseline to week 6-0.08 units on a scaleStandard Deviation 0.64
Secondary

Short Form Health Survey (SF36) General Health

The SF36 measures functional health and well-being scores on eight scales that correlate with two aggregate scores. Each score ranges from 0 to 100, with a higher score indicating better function. Mean raw scores of SF36 General Health

Time frame: Baseline, 6 weeks, 12 weeks

ArmMeasureGroupValue (MEAN)Dispersion
SildenafilShort Form Health Survey (SF36) General HealthBaseline36.99 units on a scaleStandard Deviation 9.64
SildenafilShort Form Health Survey (SF36) General Health6 week36.00 units on a scaleStandard Deviation 9.85
SildenafilShort Form Health Survey (SF36) General Health12 Week36.31 units on a scaleStandard Deviation 8.91
PlaceboShort Form Health Survey (SF36) General HealthBaseline37.66 units on a scaleStandard Deviation 8.73
PlaceboShort Form Health Survey (SF36) General Health6 week34.97 units on a scaleStandard Deviation 8.64
PlaceboShort Form Health Survey (SF36) General Health12 Week34.39 units on a scaleStandard Deviation 8.41
Secondary

St. George's Respiratory Questionnaire (Activity Score)

The St. George's Respiratory Questionnaire asks patients how breathing problems impair their life and is scored from 0 (no impairment) to 100 (maximum impairment). Mean raw scores of the St. George's Respiratory Questionnaire.

Time frame: Baseline, 6 weeks, 12 weeks

ArmMeasureGroupValue (MEAN)Dispersion
SildenafilSt. George's Respiratory Questionnaire (Activity Score)12 Week69.75 units on a scaleStandard Deviation 18.63
SildenafilSt. George's Respiratory Questionnaire (Activity Score)Change from Baseline to 6 weeks-1.95 units on a scaleStandard Deviation 10.82
SildenafilSt. George's Respiratory Questionnaire (Activity Score)6 week69.95 units on a scaleStandard Deviation 18.66
SildenafilSt. George's Respiratory Questionnaire (Activity Score)Change from Baseline to 12 weeks-1.25 units on a scaleStandard Deviation 12.56
SildenafilSt. George's Respiratory Questionnaire (Activity Score)Baseline71.20 units on a scaleStandard Deviation 17.5
PlaceboSt. George's Respiratory Questionnaire (Activity Score)Change from Baseline to 12 weeks2.77 units on a scaleStandard Deviation 13.27
PlaceboSt. George's Respiratory Questionnaire (Activity Score)Baseline68.02 units on a scaleStandard Deviation 17.63
PlaceboSt. George's Respiratory Questionnaire (Activity Score)6 week67.44 units on a scaleStandard Deviation 18.51
PlaceboSt. George's Respiratory Questionnaire (Activity Score)Change from Baseline to 6 weeks0.28 units on a scaleStandard Deviation 10.87
PlaceboSt. George's Respiratory Questionnaire (Activity Score)12 Week69.13 units on a scaleStandard Deviation 19.34
Secondary

St. George's Respiratory Questionnaire (Impacts Score)

The St. George's Respiratory Questionnaire asks patients how breathing problems impair their life and is scored from 0 (no impairment) to 100 (maximum impairment). Mean raw scores of the St. George's Respiratory Questionnaire.

Time frame: Baseline, 6 weeks, 12 weeks

ArmMeasureGroupValue (MEAN)Dispersion
SildenafilSt. George's Respiratory Questionnaire (Impacts Score)6 week41.62 units on a scaleStandard Deviation 19.49
SildenafilSt. George's Respiratory Questionnaire (Impacts Score)Change from Baseline to 6 weeks-0.67 units on a scaleStandard Deviation 12.79
SildenafilSt. George's Respiratory Questionnaire (Impacts Score)12 Week41.95 units on a scaleStandard Deviation 19.23
SildenafilSt. George's Respiratory Questionnaire (Impacts Score)Change from Baseline to 12 weeks-0.91 units on a scaleStandard Deviation 15.9
SildenafilSt. George's Respiratory Questionnaire (Impacts Score)Baseline43.20 units on a scaleStandard Deviation 19.26
PlaceboSt. George's Respiratory Questionnaire (Impacts Score)Change from Baseline to 12 weeks3.15 units on a scaleStandard Deviation 13.11
PlaceboSt. George's Respiratory Questionnaire (Impacts Score)Baseline39.77 units on a scaleStandard Deviation 18.81
PlaceboSt. George's Respiratory Questionnaire (Impacts Score)6 week41.58 units on a scaleStandard Deviation 19.68
PlaceboSt. George's Respiratory Questionnaire (Impacts Score)12 Week41.05 units on a scaleStandard Deviation 18.81
PlaceboSt. George's Respiratory Questionnaire (Impacts Score)Change from Baseline to 6 weeks2.37 units on a scaleStandard Deviation 12.94
Secondary

St. George's Respiratory Questionnaire (Symptoms Score)

The St. George's Respiratory Questionnaire asks patients how breathing problems impair their life and is scored from 0 (no impairment) to 100 (maximum impairment). Mean raw scores of the St. George's Respiratory Questionnaire. Mean raw scores of the St. George's Respiratory Questionnaire.

Time frame: Baseline, 6 weeks, 12 weeks

ArmMeasureGroupValue (MEAN)Dispersion
SildenafilSt. George's Respiratory Questionnaire (Symptoms Score)6 week55.89 units on a scaleStandard Deviation 17.72
SildenafilSt. George's Respiratory Questionnaire (Symptoms Score)Change from Baseline to 6 weeks-2.05 units on a scaleStandard Deviation 16.72
SildenafilSt. George's Respiratory Questionnaire (Symptoms Score)12 Week54.49 units on a scaleStandard Deviation 17.59
SildenafilSt. George's Respiratory Questionnaire (Symptoms Score)Change from Baseline to 12 weeks-3.57 units on a scaleStandard Deviation 17.95
SildenafilSt. George's Respiratory Questionnaire (Symptoms Score)Baseline58.20 units on a scaleStandard Deviation 17.75
PlaceboSt. George's Respiratory Questionnaire (Symptoms Score)Change from Baseline to 12 weeks2.80 units on a scaleStandard Deviation 14.74
PlaceboSt. George's Respiratory Questionnaire (Symptoms Score)Baseline53.99 units on a scaleStandard Deviation 18.9
PlaceboSt. George's Respiratory Questionnaire (Symptoms Score)6 week56.26 units on a scaleStandard Deviation 18.77
PlaceboSt. George's Respiratory Questionnaire (Symptoms Score)12 Week55.55 units on a scaleStandard Deviation 19.08
PlaceboSt. George's Respiratory Questionnaire (Symptoms Score)Change from Baseline to 6 weeks3.15 units on a scaleStandard Deviation 16.3
Secondary

St. George's Respiratory Questionnaire (Total Score)

Mean raw scores of the St. George's Respiratory Questionnaire. The St. George's Respiratory Questionnaire asks patients how breathing problems impair their life and is scored from 0 (no impairment) to 100 (maximum impairment.)

Time frame: Baseline, 6 weeks, 12 weeks

ArmMeasureGroupValue (MEAN)Dispersion
SildenafilSt. George's Respiratory Questionnaire (Total Score)6 week52.56 units on a scaleStandard Deviation 16.81
SildenafilSt. George's Respiratory Questionnaire (Total Score)Change from Baseline to 6 weeks-1.45 units on a scaleStandard Deviation 10.11
SildenafilSt. George's Respiratory Questionnaire (Total Score)12 Week52.58 units on a scaleStandard Deviation 16.35
SildenafilSt. George's Respiratory Questionnaire (Total Score)Change from Baseline to 12 weeks-1.71 units on a scaleStandard Deviation 12.35
SildenafilSt. George's Respiratory Questionnaire (Total Score)Baseline54.55 units on a scaleStandard Deviation 16.46
PlaceboSt. George's Respiratory Questionnaire (Total Score)Change from Baseline to 12 weeks2.88 units on a scaleStandard Deviation 10.61
PlaceboSt. George's Respiratory Questionnaire (Total Score)Baseline51.72 units on a scaleStandard Deviation 15.86
PlaceboSt. George's Respiratory Questionnaire (Total Score)6 week51.74 units on a scaleStandard Deviation 16.45
PlaceboSt. George's Respiratory Questionnaire (Total Score)12 Week52.19 units on a scaleStandard Deviation 16.26
PlaceboSt. George's Respiratory Questionnaire (Total Score)Change from Baseline to 6 weeks1.65 units on a scaleStandard Deviation 10.53
Secondary

University of California at San Diego (UCSD) Shortness of Breath Questionnaire Total

The University of California at San Diego Shortness of Breath Questionnaire (SOBQ) uses a 6-point scale (0 = not at all to 5 = maximal or unable to do because of breathlessness) to rate 24 items. The final score ranges from 0 to 120 -- lower scores are better. (Raw scores) Values adjusted for baseline values of age, height, sex, white race, and DLCO. Values from models are estimated changes from baseline to 12 weeks (with 95% confidence intervals). The difference estimate is based on sildenafil - placebo.

Time frame: Baseline, 6 weeks, 12 weeks

ArmMeasureGroupValue (MEAN)Dispersion
SildenafilUniversity of California at San Diego (UCSD) Shortness of Breath Questionnaire Total6 week49.67 units on a scaleStandard Deviation 22.74
SildenafilUniversity of California at San Diego (UCSD) Shortness of Breath Questionnaire TotalChange from Baseline to 6 weeks-1.27 units on a scaleStandard Deviation 12.63
SildenafilUniversity of California at San Diego (UCSD) Shortness of Breath Questionnaire Total12 Week50.58 units on a scaleStandard Deviation 23.41
SildenafilUniversity of California at San Diego (UCSD) Shortness of Breath Questionnaire TotalChange from Baseline to 12 weeks0.30 units on a scaleStandard Deviation 16.01
SildenafilUniversity of California at San Diego (UCSD) Shortness of Breath Questionnaire TotalBaseline50.71 units on a scaleStandard Deviation 22
PlaceboUniversity of California at San Diego (UCSD) Shortness of Breath Questionnaire TotalChange from Baseline to 12 weeks6.99 units on a scaleStandard Deviation 18.43
PlaceboUniversity of California at San Diego (UCSD) Shortness of Breath Questionnaire TotalBaseline43.28 units on a scaleStandard Deviation 20.18
PlaceboUniversity of California at San Diego (UCSD) Shortness of Breath Questionnaire Total6 week47.64 units on a scaleStandard Deviation 25.61
PlaceboUniversity of California at San Diego (UCSD) Shortness of Breath Questionnaire Total12 Week48.13 units on a scaleStandard Deviation 24.1
PlaceboUniversity of California at San Diego (UCSD) Shortness of Breath Questionnaire TotalChange from Baseline to 6 weeks4.42 units on a scaleStandard Deviation 17.16

Source: ClinicalTrials.gov · Data processed: Mar 31, 2026