A Study of Ubenimex in Patients with Pulmonary Arterial Hypertension


About this study

The purpose of this study is to evaluate the safety, tolerability, and effectiveness of ubenimex in patients who have pulmonary arterial hypertension, to improve exercise capacity and delay clinical worsening.

Participation eligibility

Participant eligibility includes age, gender, type and stage of disease, and previous treatments or health concerns. Guidelines differ from study to study, and identify who can or cannot participate. If you need assistance understanding the eligibility criteria, please contact the study team.

Inclusion Criteria

  • Male or female
  • 18-75 years old
  • Has a diagnosis of WHO Group 1 Pulmonary Arterial Hypertension
  • Right heart catheterization performed at screening
    • Mean pulmonary arterial pressure ≥ 25 mmHg (at rest)
    • Pulmonary venous hypertension (measured as pulmonary capillary wedge pressure (PCWP) ≤15 mmHg
      • If PCWP is not available, then mean left atrial pressure or left ventricular end-diastolic pressure ≤15 mmHg in the absence of left atrial obstruction
    • Pulmonary vascular resistance (PVR) ≥300 dyn•s/cm5 (3.75 Wood units)
  • Has WHO/NYHA-FC of II or III
  • On stable dose of at least one of the following PAH-specific therapies
    • Endothelin receptor antagonist
    • An agent acting on the nitric oxide pathway (phosphodiesterase type 5 inhibitor or soluble guanylate cyclase stimulator)
    • A prostacyclin or prostacyclin analog
  • Has a 6-minute walk distance that is ≥150 and ≤500 meters
  • Has a ventilation-perfusion scan that rules out thromboembolic disease

Exclusion Criteria

  • Related to Cardiovascular Disease
    • History of uncontrolled hypertension
    • Persistent hypotension at screening
    • Evidence or history of left-sided heart disease 
    • Clinically significant cardiac disease in which pulmonary hypertension is more likely WHO Group 2
    • Acute decompensated heart failure within 1 month of screening
    • Recent initiation (< 8 weeks from screening) or planned initiation of cardiopulmonary rehabilitation exercise program
  • Related to Pulmonary Disease
    • Newly diagnosed with PAH and not on PAH-specific therapy
    • Pulmonary hypertension due to
      • Uncorrected congenital systemic-to-pulmonary shunt
      • Pulmonary veno-occlusive disease and/or pulmonary capillary hemangiomatosis
      • Persistent pulmonary hypertension of the newborn
      • WHO clinical classification Groups 2-5
    • Evidence of significant airway and/or parenchymal lung disease
    • Chronic infection related to tuberculosis or fungal or mycobacterial diseas
  • Related to other Medical Conditions
    • Chronic infections including, but not limited to tuberculosis (TB), hepatitis B virus (HBV) or hepatitis C virus (HCV).
    • History of portal hypertension or chronic liver disease, including positive serology for infection with HCV and/or HBV
    • Evidence of active infection requiring intravenous or oral antibiotics within 4 weeks of screening
    • Body mass index ≥ 35.0 at screening
    • History of obstructive sleep apnea
    • History of malignancy within the last 5 years, except nonmelanoma skin cancer and cervical carcinoma in situ treated with curative intent
    • Neuropsychiatric disorders/symptoms or psychological conditions
    • Pregnancy or breast-feeding
    • Prior treatment with B cell or lymphocyte-depleting agents (eg, rituximab, Campath
  • Related to Concomitant Medication Use
    • Concurrent regular use of another leukotriene pathway inhibitor, including over-the-counter medications or herbal remedies
  • Related to Laboratory Values
    • Significant/chronic renal insufficiency
    • Transaminases (alanine transaminase, aspartate transaminase) levels >3 × upper limit of normal (ULN) and/or bilirubin level >2 × ULN
    • Absolute neutrophil count <1500 mm3
    • Hemoglobin concentration <9 g/dL at screening
    • Hepatic dysfunction as defined by Child-Pugh Class B or C

Participating Mayo Clinic locations

Study statuses change often. Please contact us for help.

Mayo Clinic Location Status

Rochester, Minn.

Mayo Clinic principal investigator

Robert Frantz, M.D.

Closed for enrollment

More information


Publications are currently not available

Study Results Summary

Not yet available

Supplemental Study Information

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