Please assess the completion status of the following clinical trial:

Trial Title: A Study of Sotatercept for the Treatment of Pulmonary Arterial Hypertension

Study Design Characteristics:
- Allocation: None
- Intervention Model: SINGLE_GROUP
- Observational Model: None
- Primary Purpose: TREATMENT
- Time Perspective: None
- Masking: NONE
- Phase: PHASE2
- Number of Arms: 1.0

Eligibility Criteria:
Inclusion Criteria:~1. Age ≥ 18 years~2. Documented findings on RHC at any time prior to Screening consistent with a diagnosis of World Health Organization (WHO) pulmonary hypertension Group 1: PAH of any of the following subtypes:~   * Idiopathic PAH~  * Heritable PAH~  * Drug- or toxin-induced PAH~  * PAH associated with connective tissue disease~  * PAH associated with simple, congenital systemic-to-pulmonary shunts at least 1 year following shunt repair~3. Symptomatic pulmonary hypertension classified as WHO functional class III~4. Screening RHC documenting a minimum PVR of ≥ 4 Wood units~5. Pulmonary function tests within 6 months prior to Screening as follows:~   1. Total lung capacity \> 70% predicted; or if between 60% to 70% predicted, or not possible to be determined, confirmatory high-resolution computed tomography (CT) indicating no more than mild interstitial lung disease per investigator interpretation or~  2. Forced expiratory volume (first second) (FEV1)/forced vital capacity (FVC) \> 70% predicted~  3. For subjects with a history of lobectomy or pneumonectomy, and for whom there are no population-based normalization methods, assessment based on residual lung volume will be permitted to assess eligibility.~6. Ventilation-perfusion (VQ) scan (or, if unavailable, a negative CT pulmonary angiogram \[CTPA\] or pulmonary angiography result), any time prior to Screening or conducted during Screening Period with normal or low probability result~7. 6MWD ≥ 100 and ≤ 550 meters repeated twice during Screening Period and both values within 15% of each other, calculated from the highest value~8. Combination PAH therapy at stable (per investigator) dose levels for at least 90 days prior to Cycle 1 Day 1 (C1D1)~Exclusion Criteria:~Participants will be excluded from the study if they meet any of the following criteria:~1. Started or stopped receiving any general supportive therapy for pulmonary hypertension (e.g., diuretics, oxygen, anticoagulants, digoxin) within 60 days prior to C1D1 (Cycle 1 Day 1)~2. Received intravenous inotropes (e.g., dobutamine, dopamine, norepinephrine, vasopressin) within 30 days prior to C1D1~3. History of atrial septostomy within 180 days prior to Screening~4. History of more than mild obstructive sleep apnea that is untreated~5. History of portal hypertension or chronic liver disease, defined as mild to severe hepatic impairment (Child-Pugh Classes A to C)~6. History of human immunodeficiency virus infection-associated PAH~7. Prior exposure to sotatercept (ACE-011) or luspatercept (ACE-536)~8. Uncontrolled systemic hypertension as evidenced by sitting systolic BP \> 160 mm Hg or sitting diastolic BP \> 100 mm Hg during Screening after a period of rest~9. Systolic BP \< 90 mm Hg during Screening or at baseline~10. History of known pericardial constriction~11. Electrocardiogram (ECG) with QTcF \> 480 msec during Screening or C1D1~12. History of personal or family history of long QTc syndrome or sudden cardiac death~13. History of restrictive or constrictive cardiomyopathy~14. Left ventricular ejection fraction \< 45% on echocardiogram performed within 6 months of Screening OR pulmonary capillary wedge pressure (PCWP) \> 15 mm Hg on RHC during baseline evaluation~15. Any current symptomatic coronary disease (myocardial infarction, percutaneous coronary intervention, coronary artery bypass graft surgery, or cardiac anginal chest pain in the past 6 months prior to Screening)~16. Acutely decompensated heart failure within 30 days prior to C1D1, as per investigator assessment~17. Significant (≥ 2+ regurgitation) mitral regurgitation or aortic regurgitation valvular disease

- Gender: ALL
- Minimum Age: 18 Years
- Maximum Age: None
- Healthy Volunteers: f

Study Arms:
- Sotatercept (Type: EXPERIMENTAL): Each participant will receive SOC plus sotatercept at a dose of 0.3 mg/kg SC for Cycle 1. (Each cycle will be 21 days.) From Cycle 2 through Cycle 9, the dose will be escalated to 0.7 mg/kg SC. Dosing will be every three weeks during the 24-week treatment period and 18-month extension period.

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