Please assess the completion status of the following clinical trial:

Trial Title: Effects of Bosentan on Respiratory Mechanics

Study Design Characteristics:
- Allocation: NON_RANDOMIZED
- Intervention Model: SINGLE_GROUP
- Observational Model: None
- Primary Purpose: None
- Time Perspective: None
- Masking: NONE
- Phase: PHASE4
- Number of Arms: 1.0

Eligibility Criteria:
Inclusion Criteria:~* Adult patients with World Health Organization (WHO) functional class II-III.~* A systemic pulse oximetry (SpO2) between 70% and 90% at rest with room air and a baseline 6-minute walk distance between 150 and 450 m were required for inclusion.~* PAH confirmed by cardiac catheterization as mean pulmonary arterial pressure greater or equal to25 mm Hg, pulmonary capillary wedge pressure lower 15 mm Hg,~Exclusion Criteria:~* Patients were excluded if they had patent ductus arteriosus (for hemodynamic assessment difficulties)~* complex congenital heart defect~* left ventricular dysfunction (left ventricular ejection fraction lower 40%)~* restrictive lung disease (total lung capacity lower 70% predicted)~* obstructive lung disease (forced expiratory volume in 1 second \[FEV1\] lower 70% predicted~* with FEV1/forced vital capacity lower 60%)~* or previously diagnosed coronary artery disease.

- Gender: ALL
- Minimum Age: 18 Years
- Maximum Age: 80 Years
- Healthy Volunteers: f

Study Arms:
- 1 (Type: EXPERIMENTAL): treatment with Bosentan

Based on this trial design, predict the completion outcome and termination type (if applicable).