Trial to Evaluate Parenteral Treprostinil and Riociguat on Right Ventriculo-vascular Coupling and Morphology in Those With Advanced PAH

Study Purpose

The purpose of this study is to determine if there is a greater effect to patients with advanced pulmonary arterial hypertension (PAH) by using a combination of two drugs, Treprostinil and Riociquat versus Treprostinil alone

Recruitment Criteria

Accepts Healthy Volunteers

Healthy volunteers are participants who do not have a disease or condition, or related conditions or symptoms

Study Type

An interventional clinical study is where participants are assigned to receive one or more interventions (or no intervention) so that researchers can evaluate the effects of the interventions on biomedical or health-related outcomes.

An observational clinical study is where participants identified as belonging to study groups are assessed for biomedical or health outcomes.

Searching Both is inclusive of interventional and observational studies.

Eligible Ages 18 Years and Over
Gender All
More Inclusion & Exclusion Criteria

Inclusion Criteria:

  • - WHO Category I PAH - Resting mPAP ≥ 25 mmHg with a wedge pressure of ≤ 15mmHg during right heart catheterization.
  • - Need for parenteral TRE as determined by the PH specialist caring for the patient

    Exclusion Criteria:

    - Patients with a mean arterial pressure <60, and/or requiring vasopressor support - Patients whom expected device (i.e. ECMO, RVAD) assistance or early pulmonary transplantation (within 3 months) seems inevitable - Patients with a left ventricular ejection fraction <50% or clinical, echocardiographic, and/or catheterization data consistent with heart failure with preserved ejection fraction (HFpEF) and/or moderate-severe aortic or mitral valve abnormality - Patients with severe restrictive lung disease (FVC<70% predicted) and/or obstructive lung disease (FEV1 <70% predicted and FEV1/FVC <70%).
  • - Patients with a history of pulmonary embolism within the last three months or evidence of chronic pulmonary embolism.
  • - Patients with a known contraindication to right heart catheterization.
  • - Patients whom have received active or previous pulmonary vasoactive medication within the previous 12 weeks.
  • - PAH associated with significant venous or capillary involvement (PCWP > 15 mmHg), known pulmonary veno-occlusive disease, and pulmonary capillary hemangiomatosis.
  • - Pulmonary Hypertension belonging to groups 2 to 5 of the WHO classification.
  • - Moderate to severe hepatic impairment, i.e., Child-Pugh Class B or C.
  • - Estimated creatinine clearance < 30 mL/min - Serum aspartate aminotransferase (AST) and/or alanine aminotransferase (ALT) > 1.5 times the upper limit of normal.
  • - Hemoglobin < 75% of the lower limit of the normal range.
  • - Acute or chronic physical impairment (other than dyspnea), limiting the ability to comply with study requirements.
  • - Pregnant or breast-feeding.
  • - Females must either abstain from intercourse (when it is in line with their preferred and usual lifestyle), or - Use 2 medically acceptable, highly effective forms of contraception for the duration of study, and at least 30 after discontinuing study drug.
  • - Known concomitant life-threatening disease with a life expectancy < 12 months.
  • - Body weight < 40 kg and/or >150 kg.
  • - Any condition that prevents compliance with the protocol or adherence to therapy.
  • - Concurrent therapy with strong CYP3A4 inhibitors/inducers (i.e. protease inhibitors, azole antibiotics, macrolides), theophylline, and any medication in the PI's opinion may substantially potentiate the hypotensive effect of RIO.
  • - Treatment with nitrates of any kind within the 4 weeks prior to enrollment.
  • - Known hypersensitivity to drugs of the same class as TRE and/or RIO, or any of their excipients.
  • - Planned treatment, or treatment, with another investigational drug within 1 month prior to randomization.
  • - Recent (<6 months) hemoptysis and/or history of severe hemoptysis requiring intervention (bronchial artery embolization).

Trial Details

Trial ID:

This trial id was obtained from, a service of the U.S. National Institutes of Health, providing information on publicly and privately supported clinical studies of human participants with locations in all 50 States and in 196 countries.


Phase 1: Studies that emphasize safety and how the drug is metabolized and excreted in humans.

Phase 2: Studies that gather preliminary data on effectiveness (whether the drug works in people who have a certain disease or condition) and additional safety data.

Phase 3: Studies that gather more information about safety and effectiveness by studying different populations and different dosages and by using the drug in combination with other drugs.

Phase 4: Studies occurring after FDA has approved a drug for marketing, efficacy, or optimal use.

Phase 3
Lead Sponsor

The sponsor is the organization or person who oversees the clinical study and is responsible for analyzing the study data.

University of Arizona
Principal Investigator

The person who is responsible for the scientific and technical direction of the entire clinical study.

Franz Rischard, DO
Principal Investigator Affiliation University of Arizona
Agency Class

Category of organization(s) involved as sponsor (and collaborator) supporting the trial.

Overall Status Recruiting
Countries United States

The disease, disorder, syndrome, illness, or injury that is being studied.

Pulmonary Arterial Hypertension
Additional Details

The purpose of this study is to evaluate the combined effect of parenteral treprostinil (TRE) and riociguat (RIO) versus parenteral TRE alone on right ventricular (RV)-pulmonary artery (PA) interaction (RVPA coupling) and global RV function in patients with advanced pulmonary arterial hypertension (PAH).

Arms & Interventions


Experimental: Experimental

Treprostinil and Riociguat


Drug: - Treprostinil Injectable Product


Drug: - Riociguat Pill


Contact a Trial Team

If you are interested in learning more about this trial, find the trial site nearest to your location and contact the site coordinator via email or phone. We also strongly recommend that you consult with your healthcare provider about the trials that may interest you and refer to our terms of service below.

University of Arizona, Tucson, Arizona




University of Arizona

Tucson, Arizona, 85724

Site Contact

Valerie Bloss, MS


For more information, please contact PHA at and refer to the terms of service below.

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