[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"health-study-detail:100593954":3},{"organization":4,"armGroups":7,"interventions":19,"overallOfficials":10,"centralContacts":29,"locations":36,"responsibleParty":53,"collaborators":10,"id":56,"slug":57,"hasResults":58,"nctId":59,"briefTitle":60,"officialTitle":61,"acronym":62,"eligibilityCriteria":63,"healthyVolunteers":58,"sex":64,"minAge":65,"maxAge":10,"enrollmentInfo":66,"targetDuration":10,"studyType":69,"phases":10,"briefSummary":70,"conditions":71,"keywords":75,"overallStatus":39,"whyStopped":10,"lastUpdateSubmitDate":83,"lastUpdatePostDateStruct":84,"startDateStruct":87,"completionDateStruct":89,"leadSponsor":91,"locationsCount":92},{"fullName":5,"class":6},"University of Sao Paulo General Hospital","OTHER",[8,14],{"label":9,"type":10,"description":11,"interventionNames":12},"Patients who switched from Ambrisentan to Bosentan",null,"This cohort includes adult patients (≥18 years) with a confirmed diagnosis of pulmonary arterial hypertension (PAH) by right heart catheterization who underwent a therapeutic transition from ambrisentan 10 mg once daily to bosentan 125 mg twice daily within the past 6 months. Patients are followed during routine clinical care and assessed between 3 and 6 months after the switch to evaluate changes in risk stratification scores (COMPERA 2.0 and REVEAL Lite 2.0), functional capacity, laboratory parameters, and adverse events. No investigational drug or additional intervention is administered beyond standard care.",[13],"Other: Switch from Ambrisentan to Bosentan",{"label":15,"type":10,"description":16,"interventionNames":17},"Ambrisentan Maintenance Group","This cohort includes adult patients (≥18 years) with a confirmed diagnosis of pulmonary arterial hypertension (PAH) by right heart catheterization who remained on ambrisentan 10 mg once daily and did not undergo a therapeutic switch to bosentan. Clinical, functional, and laboratory data recorded at baseline are compared with data recorded between 3 and 6 months later to evaluate changes in risk stratification scores, functional capacity, laboratory parameters, and clinical events. No investigational drug or additional intervention was administered beyond standard care.",[18],"Drug: Maintenance of Ambrisentan Therapy",[20,24],{"type":6,"name":21,"description":22,"armGroupLabels":23,"otherNames":10},"Switch from Ambrisentan to Bosentan","This intervention refers to a therapeutic switch from ambrisentan (10 mg once daily) to bosentan (125 mg twice daily) in adult patients with pulmonary arterial hypertension (PAH), performed as part of routine clinical care. The switch was not assigned by the investigators but was made based on clinical indications prior to study enrollment. Patients are followed prospectively for up to 6 months to assess changes in risk stratification, functional status, laboratory parameters, and safety outcomes.",[9],{"type":25,"name":26,"description":27,"armGroupLabels":28,"otherNames":10},"DRUG","Maintenance of Ambrisentan Therapy","Continued treatment with ambrisentan 10 mg once daily without transition to bosentan, as part of routine clinical care. Treatment was not assigned by the investigators. Clinical, functional, laboratory, and safety outcomes are assessed over a 3- to 6-month period.",[15],[30],{"name":31,"role":32,"phone":33,"phoneExt":34,"email":35},"Caio Fernandes, Principal Investigator","CONTACT","PhD","+551126611548","caio.cesar@hc.fm.usp.br",[37],{"facility":38,"status":39,"city":40,"state":40,"zip":10,"country":41,"countryCode":42,"cosmosGeoPoint":43,"geoPoint":48,"contacts":49},"InCor - FMUSP","RECRUITING","São Paulo","Brazil","BR",{"type":44,"coordinates":45},"Point",[46,47],-46.63611,-23.5475,{"lat":47,"lon":46},[50],{"name":51,"role":32,"phone":52,"phoneExt":10,"email":35},"Caio Fernandes, PhD","+55 11 2661-1548",{"type":54,"investigatorFullName":55,"investigatorTitle":33,"investigatorAffiliation":5,"oldNameTitle":10,"oldOrganization":10},"PRINCIPAL_INVESTIGATOR","Caio Júlio César dos Santos Fernandes","100593954","the-impact-of-era-switching-on-risk-stratification-in-pulmonary-arterial-hypertension-100593954",false,"NCT07013149","The Impact of ERA Switching on Risk Stratification in Pulmonary Arterial Hypertension","ACTION - The Impact of ERA Switching on Risk Stratification in Pulmonary Arterial Hypertension","ACTION","Inclusion Criteria:\n\n* Age ≥ 18 years\n* Confirmed diagnosis of pulmonary arterial hypertension (PAH) by right heart catheterization\n* Documented therapeutic switch from ambrisentan (10 mg once daily) to bosentan (125 mg twice daily) within the previous 6 months for the switch group\n* Treatment with ambrisentan for at least 6 months without switching to bosentan for the maintenance group\n\nExclusion Criteria:\n\n* History of severe hepatic impairment\n* Incomplete clinical or laboratory records that prevent risk score calculation\n* Inability to attend clinical follow-up between 3 and 6 months after medication switch","ALL","18 Years",{"count":67,"type":68},183,"ESTIMATED","OBSERVATIONAL","Pulmonary arterial hypertension (PAH) is a rare, progressive, and potentially life-threatening disease characterized by pulmonary vascular remodeling, increased pulmonary vascular resistance, and right ventricular dysfunction. The endothelin pathway plays a central role in its pathophysiology and is targeted by endothelin receptor antagonists (ERAs), including ambrisentan and bosentan.\n\nAmbrisentan is a selective ETA receptor antagonist, whereas bosentan blocks both ETA and ETB receptors. Although transitions between ERAs occur in clinical practice, evidence regarding the clinical impact of switching from ambrisentan to bosentan remains limited.\n\nACTION is a retrospective, observational, single-center cohort study evaluating adult patients with pulmonary arterial hypertension (World Health Organization Group 1) and\u002For chronic thromboembolic pulmonary hypertension (World Health Organization Group 4) confirmed by right heart catheterization. Patients who switched from ambrisentan to bosentan because of a national ambrisentan shortage will be compared with clinically similar patients who remained on ambrisentan.\n\nClinical, functional, and laboratory data recorded at baseline and at 3 to 6 months of follow-up will be assessed. The primary outcome is the proportion of patients with worsening risk stratification after switching from ambrisentan to bosentan compared with patients who continued ambrisentan. Risk will be evaluated using the COMPERA 2.0 and REVEAL Lite 2 assessment tools.\n\nSecondary outcomes include changes in World Health Organization\u002FNew York Heart Association functional class, 6-minute walk distance, BNP levels, individual risk-assessment components, hepatic enzymes, hemoglobin levels, and clinically relevant events such as hospitalization, emergency department visits, initiation of supplemental oxygen, and right heart failure decompensation.",[72,73,74],"Pulmonary Arterial Hypertension","Pulmonary Arterial Hypertension (PAH)","Pulmonary Arterial Hypertension (PAH) (WHO Group 1 PH)",[72,76,77,78,79,80,81,82],"PAH","Endothelin Receptor Antagonists","ERA","Ambrisentan","Bosentan","Drug Switching","Risk Stratification","2026-07-01",{"date":85,"type":86},"2026-07-06","ACTUAL",{"date":88,"type":86},"2025-08-20",{"date":90,"type":68},"2026-12-01",{"name":5,"class":6},1]