| 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. | | Posted | | Number | | participants | | Measured at Week 12 | | | | ID | Title | Description |
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| OG000 | Sildenafil | 20 mg of oral sildenafil 3 times per day for 12 weeks, followed by 20 mg oral sildenafil 3 times per day for an additional 12 weeks. | | OG001 | 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 |
| | | Title | Denominators | Categories |
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| | Group IDs | Group Description | Statistical Method | Statistical Comment | P-Value | P-Value Comment | Parameter Type | Parameter Value | Dispersion Type | Dispersion Value | Confidence Interval Sides | Confidence Interval % | CI Lower Limit | CI Upper Limit | CI Lower Limit Comment | CI Upper Limit Comment | Estimate Comment | Tested Non-Inferiority | Non-Inferiority Type | Non-Inferiority Comment | Other Analysis Description |
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| | Chi-squared | | 0.39 | | | | | | | | | | | | | No | Superiority or Other | | |
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| Secondary | 6-minute Walk Distance (6MWT) | The 6MWT measures the distance that a participant can walk in a period of 6 minutes. | | Posted | | Mean | Standard Deviation | meters | | Baseline, 6 week, 12 week | | | | ID | Title | Description |
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| OG000 | Sildenafil | 20 mg of oral sildenafil 3 times per day for 12 weeks, followed by 20 mg oral sildenafil 3 times per day for an additional 12 weeks. | | OG001 | 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 |
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| 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. | | Posted | | Mean | 95% Confidence Interval | meters | | Baseline, week 12 | | | | ID | Title | Description |
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| OG000 | Sildenafil | 20 mg of oral sildenafil 3 times per day for 12 weeks, followed by 20 mg oral sildenafil 3 times per day for an additional 12 weeks. | | OG001 | 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 |
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| 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. | | Posted | | Number | 95% Confidence Interval | percentage of participants | | Week 12 | | | | ID | Title | Description |
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| OG000 | Sildenafil / Sildenafil | 20 mg oral sildenafil 3 times per day | | OG001 | Placebo / Sildenafil | 20 mg oral placebo 3 times per day |
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| 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. | | Posted | | Mean | 95% Confidence Interval | units on a scale | | Measured from enrollment to 12 weeks (phase I) | | | | ID | Title | Description |
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| OG000 | 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 | | OG001 | 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 |
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| 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. | | Posted | | Mean | Standard Deviation | units on a scale | | Baseline, 6 weeks, 12 weeks | | | | ID | Title | Description |
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| OG000 | Sildenafil | 20 mg of oral sildenafil 3 times per day for 12 weeks, followed by 20 mg oral sildenafil 3 times per day for an additional 12 weeks. | | OG001 | 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 |
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| 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. | | Posted | | Least Squares Mean | 95% Confidence Interval | liters | | Baseline, Week 12 | | | | ID | Title | Description |
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| OG000 | Sildenafil / Sildenafil | 20 mg oral sildenafil 3 times per day | | OG001 | Placebo / Sildenafil | 20 mg oral placebo 3 times per day |
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| 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 | | Posted | | Mean | Standard Deviation | liters | | Baseline, Week 6, Week 12 | | | | ID | Title | Description |
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| OG000 | Sildenafil / Sildenafil | 20 mg oral sildenafil 3 times per day | | OG001 | Placebo / Sildenafil | 20 mg oral placebo 3 times per day |
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| 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. | | Posted | | Least Squares Mean | 95% Confidence Interval | percentage of predicted (DLCO) | | Baseline, Week 12 | | | | ID | Title | Description |
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| OG000 | Sildenafil / Sildenafil | 20 mg oral sildenafil 3 times per day | | OG001 | Placebo / Sildenafil | 20 mg oral placebo 3 times per day |
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| 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 | | Posted | | Mean | Standard Deviation | percentage of predicted (DLCO) | | Baseline, Week 6, Week 12 | | | | ID | Title | Description |
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| OG000 | Sildenafil / Sildenafil | 20 mg oral sildenafil 3 times per day | | OG001 | Placebo / Sildenafil | 20 mg oral placebo 3 times per day |
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| 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. | | Posted | | Mean | 95% Confidence Interval | units on a scale | | Baseline, 12 week | | | | ID | Title | Description |
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| OG000 | Sildenafil | 20 mg of oral sildenafil 3 times per day for 12 weeks, followed by 20 mg oral sildenafil 3 times per day for an additional 12 weeks. | | OG001 | 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 |
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| 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. | | Posted | | Mean | Standard Deviation | units on a scale | | Baseline, 6 week, 12 week | | | | ID | Title | Description |
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| OG000 | Sildenafil | 20 mg of oral sildenafil 3 times per day for 12 weeks, followed by 20 mg oral sildenafil 3 times per day for an additional 12 weeks. | | OG001 | 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 |
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| 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. | | Posted | | Mean | 95% Confidence Interval | units on a scale | | Baseline, 12 week | | | | ID | Title | Description |
|---|
| OG000 | Sildenafil | 20 mg of oral sildenafil 3 times per day for 12 weeks, followed by 20 mg oral sildenafil 3 times per day for an additional 12 weeks. | | OG001 | 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 |
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| 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.) | | Posted | | Mean | Standard Deviation | units on a scale | | Baseline, 6 weeks, 12 weeks | | | | ID | Title | Description |
|---|
| OG000 | Sildenafil | 20 mg of oral sildenafil 3 times per day for 12 weeks, followed by 20 mg oral sildenafil 3 times per day for an additional 12 weeks. | | OG001 | 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 |
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| 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. | | Posted | | Mean | 95% Confidence Interval | units on a scale | | Baseline, 12 weeks | | | | ID | Title | Description |
|---|
| OG000 | Sildenafil | 20 mg of oral sildenafil 3 times per day for 12 weeks, followed by 20 mg oral sildenafil 3 times per day for an additional 12 weeks. | | OG001 | 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 |
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| 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. | | Posted | | Mean | Standard Deviation | units on a scale | | Baseline, 6 weeks, 12 weeks | | | | ID | Title | Description |
|---|
| OG000 | Sildenafil | 20 mg of oral sildenafil 3 times per day for 12 weeks, followed by 20 mg oral sildenafil 3 times per day for an additional 12 weeks. | | OG001 | 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 |
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| 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. | | Posted | | Mean | 95% Confidence Interval | units on a scale | | Baseline, 12 weeks | | | | ID | Title | Description |
|---|
| OG000 | Sildenafil | 20 mg of oral sildenafil 3 times per day for 12 weeks, followed by 20 mg oral sildenafil 3 times per day for an additional 12 weeks. | | OG001 | 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 |
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| 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. | | Posted | | Mean | Standard Deviation | units on a scale | | Baseline, 6 weeks, 12 weeks | | | | ID | Title | Description |
|---|
| OG000 | Sildenafil | 20 mg of oral sildenafil 3 times per day for 12 weeks, followed by 20 mg oral sildenafil 3 times per day for an additional 12 weeks. | | OG001 | 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 |
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| 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. | | Posted | | Mean | 95% Confidence Interval | units on a scale | | Baseline, 12 weeks | | | | ID | Title | Description |
|---|
| OG000 | Sildenafil | 20 mg of oral sildenafil 3 times per day for 12 weeks, followed by 20 mg oral sildenafil 3 times per day for an additional 12 weeks. | | OG001 | 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 |
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| 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. | | Posted | | Mean | Standard Deviation | units on a scale | | Baseline, 6 weeks, 12 weeks | | | | ID | Title | Description |
|---|
| OG000 | Sildenafil | 20 mg of oral sildenafil 3 times per day for 12 weeks, followed by 20 mg oral sildenafil 3 times per day for an additional 12 weeks. | | OG001 | 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 |
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| 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. | | Posted | | Mean | 95% Confidence Interval | units on a scale | | Baseline, 12 weeks | | | | ID | Title | Description |
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| OG000 | Sildenafil | 20 mg of oral sildenafil 3 times per day for 12 weeks, followed by 20 mg oral sildenafil 3 times per day for an additional 12 weeks. | | OG001 | 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 |
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| 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. | | Posted | | Mean | Standard Deviation | units on a scale | | Baseline, 6 weeks, 12 weeks | | | | ID | Title | Description |
|---|
| OG000 | Sildenafil | 20 mg of oral sildenafil 3 times per day for 12 weeks, followed by 20 mg oral sildenafil 3 times per day for an additional 12 weeks. | | OG001 | 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 |
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| 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. | | Posted | | Mean | 95% Confidence Interval | units on a scale | | Baseline, 12 weeks | | | | ID | Title | Description |
|---|
| OG000 | Sildenafil | 20 mg of oral sildenafil 3 times per day for 12 weeks, followed by 20 mg oral sildenafil 3 times per day for an additional 12 weeks. | | OG001 | 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 |
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| 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. | | Posted | | Mean | Standard Deviation | units on a scale | | Baseline, 6 weeks, 12 weeks | | | | ID | Title | Description |
|---|
| OG000 | Sildenafil | 20 mg of oral sildenafil 3 times per day for 12 weeks, followed by 20 mg oral sildenafil 3 times per day for an additional 12 weeks. | | OG001 | 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 |
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| 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. | | Posted | | Mean | 95% Confidence Interval | units on a scale | | Baseline, 12 weeks | | | | ID | Title | Description |
|---|
| OG000 | Sildenafil | 20 mg of oral sildenafil 3 times per day for 12 weeks, followed by 20 mg oral sildenafil 3 times per day for an additional 12 weeks. | | OG001 | 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 |
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| 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. | | Posted | | Mean | Standard Deviation | units on a scale | | Baseline, 6 weeks, 12 weeks | | | | ID | Title | Description |
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| OG000 | Sildenafil | 20 mg of oral sildenafil 3 times per day for 12 weeks, followed by 20 mg oral sildenafil 3 times per day for an additional 12 weeks. | | OG001 | 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 |
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| 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. | | Posted | | Mean | 95% Confidence Interval | units on a scale | | Baseline, 12 weeks | | | | ID | Title | Description |
|---|
| OG000 | Sildenafil | 20 mg of oral sildenafil 3 times per day for 12 weeks, followed by 20 mg oral sildenafil 3 times per day for an additional 12 weeks. | | OG001 | 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 |
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| 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 | | Posted | | Mean | Standard Deviation | units on a scale | | Baseline, 6 weeks, 12 weeks | | | | ID | Title | Description |
|---|
| OG000 | Sildenafil | 20 mg of oral sildenafil 3 times per day for 12 weeks, followed by 20 mg oral sildenafil 3 times per day for an additional 12 weeks. | | OG001 | 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 |
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| 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. | | Posted | | Mean | 95% Confidence Interval | units on a scale | | Baseline, 12 weeks | | | | ID | Title | Description |
|---|
| OG000 | Sildenafil | 20 mg of oral sildenafil 3 times per day for 12 weeks, followed by 20 mg oral sildenafil 3 times per day for an additional 12 weeks. | | OG001 | 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 |
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| 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. | | Posted | | Mean | Standard Deviation | units on a scale | | Baseline, 6 weeks, 12 weeks | | | | ID | Title | Description |
|---|
| OG000 | Sildenafil | 20 mg of oral sildenafil 3 times per day for 12 weeks, followed by 20 mg oral sildenafil 3 times per day for an additional 12 weeks. | | OG001 | 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 |
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