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Randomized Study of Triple Therapy vs Sildenafil Dose Optimization in Pulmonary Arterial Hypertension

A Prospective, Randomized, Open-Label Study Comparing Triple Therapy Versus Sildenafil Dose Optimization in Patients With Pulmonary Arterial Hypertension Using COMPERA 2.0 Risk Stratification as the Primary Outcome

Status
Recruiting
Phases
Phase 4
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT07713914
Acronym
ASCEND-PAH
Enrollment
196
Registered
2026-07-20
Start date
2026-07-22
Completion date
2028-12-31
Last updated
2026-07-30

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Pulmonary Arterial Hypertension (PAH)

Keywords

Pulmonary Arterial Hypertension, Therapeutic Escalation, Triple Therapy, Sildenafil Dose Optimization, Randomized Clinical Trial

Brief summary

Pulmonary arterial hypertension (PAH) is a rare and progressive disease characterized by increased pressure in the pulmonary arteries, leading to right heart failure and premature death. Although combination therapy has improved outcomes, many patients remain at intermediate or high clinical risk despite treatment. When patients do not reach low-risk status, treatment escalation is recommended. However, different escalation strategies are used in clinical practice, including increasing the dose of existing medications or adding a third drug that targets a different biological pathway. There is limited prospective randomized evidence directly comparing these approaches. The ASCEND-PAH study is a prospective, randomized, open-label clinical trial designed to compare two therapeutic escalation strategies in adults with PAH who remain at intermediate or high risk despite dual therapy with an endothelin receptor antagonist and sildenafil. Participants will be randomized to either: (1) escalation to triple therapy with the addition of a prostacyclin pathway agent, or (2) optimization of dual therapy by increasing the dose of sildenafil. The primary objective is to compare the proportion of patients who improve their risk category according to the COMPERA 2.0 four-stratum risk model within 3 to 6 months after randomization. Secondary outcomes include changes in functional status, exercise capacity, biomarkers, clinical worsening, safety, and treatment persistence

Detailed description

This is a prospective, randomized, open-label, parallel-group clinical trial designed to evaluate therapeutic escalation strategies in adults with pulmonary arterial hypertension (PAH, Group 1) who remain at intermediate-low, intermediate-high, or high risk according to the COMPERA 2.0 four-stratum model despite stable dual therapy. Eligible participants must be receiving an endothelin receptor antagonist in combination with sildenafil and have a clinical indication for treatment escalation. After confirmation of eligibility and baseline assessments, participants will be randomized in a 1:1 ratio to one of two strategies: Escalation to triple therapy through addition of a prostacyclin pathway agent (inhaled iloprost or selexipag), according to clinical judgment and availability. Optimization of dual therapy by increasing the dose of sildenafil according to clinical practice. Baseline assessments may include WHO functional class, 6-minute walk distance, and BNP or NT-proBNP levels obtained within 90 days prior to randomization. Follow-up evaluation will occur between 3 and 6 months after randomization, with the primary analysis based on the assessment closest to 6 months within that window. The primary endpoint is the proportion of patients who achieve improvement in risk stratification, defined as a decrease of at least one risk category according to the COMPERA 2.0 four-stratum model. Secondary endpoints include composite clinical improvement and worsening, change in individual clinical parameters, time to clinical worsening, safety outcomes, need for additional therapeutic escalation, and treatment persistence. The study is powered to detect a clinically meaningful absolute difference of 20 percentage points in risk improvement between groups, with planned enrollment of approximately 196 participants to account for potential losses to follow-up

Interventions

DRUGProstacyclin Pathway Agent

Addition of a prostacyclin pathway agent (inhaled iloprost or oral selexipag) to ongoing dual therapy with an endothelin receptor antagonist and sildenafil as part of therapeutic escalation to triple therapy. The specific agent will be selected according to clinical judgment and availability. Dosing will follow approved labeling and routine clinical practice.

DRUGSildenafil Dose Optimization

Optimization of sildenafil dose within approved dosing ranges as part of dual therapy with an endothelin receptor antagonist. Dose adjustments will be performed according to clinical practice to achieve maximal tolerated and guideline-recommended dosing without addition of a new PAH pathway agent at randomization.

Sponsors

University of Sao Paulo General Hospital
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE

Masking description

This is an open-label study. Neither participants nor investigators are blinded to treatment allocation. No outcome assessors or data analysts are formally masked.

Intervention model description

Participants will be randomized in a 1:1 ratio to one of two parallel treatment strategies: (1) escalation to triple therapy through addition of a prostacyclin pathway agent (inhaled iloprost or selexipag) to ongoing dual therapy, or (2) optimization of dual therapy by increasing the dose of sildenafil. Participants will remain in their assigned strategy throughout the follow-up period, and outcomes will be assessed between 3 and 6 months after randomization.

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* Age ≥18 years * Diagnosis of pulmonary arterial hypertension (PAH, Group 1) confirmed according to accepted clinical and hemodynamic criteria * Stable treatment with an endothelin receptor antagonist in combination with sildenafil prior to randomization * Classified as intermediate-low, intermediate-high, or high risk according to the COMPERA 2.0 four-stratum model * Clinical indication for therapeutic escalation * Availability for follow-up assessment between 3 and 6 months after randomization * Ability to provide written informed consent

Exclusion criteria

* Participation in another interventional clinical trial that mandates treatment modification * Known contraindication to prostacyclin pathway agents (including iloprost or selexipag) * Known contraindication to sildenafil dose escalation * Pregnancy or breastfeeding * Women of childbearing potential not using effective contraception * Any clinical condition that, in the investigator's judgment, would interfere with study participation or outcome assessment

Design outcomes

Primary

MeasureTime frameDescription
Improvement in Risk Stratification According to the COMPERA 2.0 Four-Stratum ModelBetween 3 and 6 months after randomization (assessment closest to 6 months within the predefined window)Proportion of participants who achieve improvement in clinical risk category between baseline and follow-up, defined as a decrease of at least one risk category according to the COMPERA 2.0 four-stratum model (low, intermediate-low, intermediate-high, high risk). Risk status is determined using World Health Organization functional class, 6-minute walk distance, and BNP or NT-proBNP levels, when available.

Secondary

MeasureTime frameDescription
Composite Clinical Improvement at 3-6 MonthsBetween 3 and 6 months after randomizationProportion of participants who achieve composite clinical improvement between baseline and follow-up (3-6 months), defined as improvement in at least two of the following without worsening in any: (1) improvement of ≥1 WHO functional class; (2) increase of ≥30 meters in 6-minute walk distance; (3) reduction of ≥30% in BNP or NT-proBNP levels.
Composite Clinical WorseningFrom randomization through 6 months of follow-upOccurrence of clinical worsening defined as any of the following during follow-up: worsening of ≥1 WHO functional class; decrease of ≥30 meters in 6-minute walk distance; increase of ≥30% in BNP or NT-proBNP; need for additional therapeutic escalation; hospitalization related to pulmonary arterial hypertension; or death from any cause.
Change in WHO Functional ClassBetween 3 and 6 months after randomizationChange in World Health Organization (WHO) functional class between baseline and follow-up. WHO functional class ranges from I (least severe) to IV (most severe), with higher classes indicating worse functional limitation.
Change in 6-Minute Walk Distance (6MWD)Between 3 and 6 months after randomizationAbsolute change in 6-minute walk distance (meters) between baseline and follow-up assessment.
Change in BNP or NT-proBNP LevelsBetween 3 and 6 months after randomizationPercent change in BNP or NT-proBNP levels between baseline and follow-up. Higher values indicate greater cardiac strain and worse prognosis.
Time to Clinical WorseningFrom randomization through 6 months of follow-upTime from randomization to first occurrence of clinical worsening event as defined in the composite clinical worsening outcome.
Treatment PersistenceFrom randomization through 6 months of follow-upProportion of participants who remain on their initially assigned therapeutic strategy without permanent discontinuation by the follow-up visit.
Safety and Adverse EventsFrom randomization through 6 monthsIncidence, type, and severity of adverse events and serious adverse events occurring during the study period.

Countries

Brazil

Contacts

CONTACTCaio Fernandes, MD, PhD
cjcfernandes@yahoo.com.br+551126615034
PRINCIPAL_INVESTIGATORCaio Fernandes

Instituto do Coração (InCor), Hospital das Clínicas HCFMUSP, Faculdade de Medicina, Universidade de São Paulo

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Jul 31, 2026