Assess the Efficacy and Safety of Sildenafil When Added to Bosentan in the Treatment of Pulmonary Arterial Hypertension
To assess the efficacy and safety of sildenafil when added to patients with PAH who are taking bosentan as all or part of their background therapy.
Pulmonary Arterial Hypertension
Drug: Sildenafil Citrate
|Study Design:||Allocation: Randomized
Endpoint Classification: Safety/Efficacy Study
Intervention Model: Parallel Assignment
Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor)
Primary Purpose: Treatment
|Official Title:||A Multinational, Multicentre, Randomized, Double-Blind Study To Assess The Efficacy And Safety Of Oral Sildenafil 20mg TID Or Placebo When Added To Bosentan In The Treatment Of Subjects, Aged 18 Years And Above, With Pulmonary Arterial Hypertension (PAH).|
- Change From Baseline in the Total Distance Walked During 6 Minute Walk Time (6MWT) at Week 12 [ Time Frame: Week 12 ] [ Designated as safety issue: No ]6MWT is the distance that a participant could walk in 6 minutes. Participants were asked to perform the test at a pace that was comfortable to them, with as many breaks as they needed. Continuous pulse oximetry was conducted during the test for safety.
- Number of Participants With Change From Baseline in World Health Organization (WHO) Functional Class in Participants With PAH at Week 12 LOCF [ Time Frame: Week 12 ] [ Designated as safety issue: No ]WHO functional classification for PAH range from Class I (no limitation in physical activity, no dyspnea with normal activity) to Class IV (can not perform a physical activity without any symptoms, dyspnea at rest). Improvement=reduction in functional class; deterioration = increase in functional class, no change = no change in functional class.
- Clinical Worsening Events [ Time Frame: Week 12 ] [ Designated as safety issue: No ]
No survival analysis was carried out for the study due to very few events of clinical worsening. Hence, we present a summary of clinical worsening events instead.
Events of clinical worsening were categorized as (A). Death, (B). Heart/lung transplantation, (C). Hospitalization due to pulmonary arterial hypertension (PAH), and (D). Clinical deterioration of PAH requiring additional therapy.
- Change From Baseline in Borg Dyspnea Score at Week 12 [ Time Frame: Week 12 ] [ Designated as safety issue: No ]
Borg dyspnea scale is a 10-point scale where following scores stands for severity of dyspnea: 0 (no breathlessness at all); 0.5 (very very slight [just noticeable]);
- (very slight);
- (slight breathlessness);
- (moderate); 4 (some what severe);
5 (severe breathlessness); 7 (very severe breathlessness); 9 (very very severe [almost maximum]); and 10 (maximum).
|Study Start Date:||September 2006|
|Study Completion Date:||August 2013|
|Primary Completion Date:||August 2012 (Final data collection date for primary outcome measure)|
|Placebo Comparator: placebo||
Bosentan + Placebo for 12 weeks of the study (double blind), then 12 months open label phase (bosentan + sildenafil)Drug: Placebo
Placebo for 12 weeks of the study (double blind), then 12 months open label phase (bosentan + sildenafil)
Drug: Sildenafil Citrate
Bosentan + Sildenafil for 12 weeks of the study (double blind), then 12 months open label phase
Please refer to this study by its ClinicalTrials.gov identifier: NCT00323297
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|Study Director:||Pfizer CT.gov Call Center||Pfizer|