Mean change from baseline was calculated as the Week 12 value minus the baseline value. 6MWD was measured by a 6 minute walk test. This test measures the distance that a subject can walk in a period of 6 minutes.

Full Analysis Set (FAS): all participants registered, with the exception of those who had not received any dose of the investigational product and those who had no efficacy assessment after administration of the investigational product. Imputation technique was last observation carried forward.

Change from baseline was calculated as the Week 24/Withdrawal value minus the basline value. 6MWD was measured by a 6 minute walk test. This test measures the distance that a subject can walk in a period of 6 minutes. Imputation technique was last observation carried forward.

Full Analysis Set

The BDI was calculated by using a 10-point scale (0 = None, 10 = Maximum). Change from baseline was calculated as the Week 12 and 24 values minus the baseline values. The BDI indicates the degree of breathlessness after completion of the 6 minute walk test. The BDI scale was assessed by each participant. Imputation technique was last observation carried forward.

Full Analysis Set

There are four grades for WHO FC (class I = none, Class IV = most severe). The WHO FC indicates the severity of Pulmonary Arterial Hypertension and is an adaptation of the New York Heart Association classification. It was assessed by the investigator. Imputation technique was last observation carried forward.

Full Analysis Set

Time to clinical worsening is defined as the time from baseline to the first occurrence of death, lung transplantation, hospitalization for PAH treatment, atrial septostomy, or study discontinuation due to change to other PAH treatment. Time to clinical worsening is measured as the number of participants who experienced these events during 24 weeks.

Full Analysis Set: : all participants registered, with the exception of those who had not received any dose of the investigational product and those who had no efficacy assessment after administration of the investigational product

mPAP and mRAP are measures of cardiopulmonary hemodynamics. Change from baseline was calculated as the Week 12 and 24 values minus the baseline value. Observed data analysis (no imputation techniques).

Full Analysis Set: Analysis was conducted using observed data only. Some participants were withdrawn before Week 24, or some participants could not be measured at Week 24 in this study.

CI is a measure of cardiopulmonary hemodynamics. Change from baseline was calculated as the Week 12 and 24 values minus the baseline value. Observed data analysis (no imputation techniques).

Full Analysis Set: Analysis was conducted using observed data only. Some participants were withdrawn before Week 24, or some participants could not be measured at Week 24 in this study.

CO is a measure of cardiopulmonary hemodynamics. Change from baseline was calculated as the Week 12 and 24 values minus the baseline value. Observed data analysis (no imputation techniques).

Full Analysis Set: Analysis was conducted using observed data only. Some participants were withdrawn before Week 24, or some participants could not be measured at Week 24 in this study.

PVR is a measure of cardiopulmonary hemodynamics. Change from baseline was calculated as the Week 12 and 24 values minus the baseline value. Observed data analysis (no imputation techniques).

Full Analysis Set: Analysis was conducted using observed data only. Some participants were withdrawn before Week 24, or some participants could not be measured at Week 24 in this study.

Change from baseline was calculated as the Week 12 and 24 values minus the baseline value. BNP is a surrogate maker of heart failure and was measured by a central laboratory. Observed data analysis (no imputation techniques).

Full Analysis Set: Analysis was conducted using observed data only. Some participants were withdrawn before Week 24, or some participants could not be measured at Week 24 in this study.