Effect of Riociguat on Early Pulmonary Vascular Disease

Efficacy and Safety of Riociguat (MK-4836) in Incipient Pulmonary Vascular Disease as an Indicator for Early Pulmonary Arterial Hypertension Double-blind, Randomized, Multicenter, Multinational, Placebo-controlled Phase IIa Study (ESRA)

Phase 2 Interventional Heidelberg University · NCT05339087

This study is testing if the medication riociguat can help people with early pulmonary vascular disease feel better by lowering their blood pressure in the lungs.

Quick facts

PhasePhase 2
Study typeInterventional
Enrollment70 (estimated)
Ages18 Years and up
SexAll
SponsorHeidelberg University Academic / other
Locations8 sites (Graz and 7 other locations)
Trial IDNCT05339087 on ClinicalTrials.gov

What this trial studies

This clinical trial investigates the efficacy and safety of riociguat in patients with early pulmonary vascular disease, specifically targeting those with mildly elevated pulmonary arterial pressures. The study is randomized, double-blind, and placebo-controlled, involving multiple centers across different countries. It aims to assess the impact of riociguat on pulmonary vascular resistance (PVR) and other clinical parameters, with a focus on patients who have not previously received PAH-specific treatments. The trial seeks to provide insights into the potential benefits of early intervention in this patient population.

Who should consider this trial

Good fit: Ideal candidates include adults aged 18 and older with early pulmonary vascular disease characterized by specific pulmonary arterial pressure and resistance measurements.

Not a fit: Patients with advanced pulmonary arterial hypertension or those already receiving PAH-specific treatments may not benefit from this study.

Why it matters

Potential benefit: If successful, this treatment could improve outcomes for patients with early pulmonary vascular disease by potentially preventing the progression to more severe pulmonary hypertension.

How similar studies have performed: Previous studies have shown positive effects of similar treatments on pulmonary vascular resistance, indicating potential for success in this approach.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

1. ≥18 years of age at time of inclusion.
2. Male and female patients with early pulmonary vascular disease, defined as either a) mean pulmonary arterial pressure (mPAP) ≥25 mmHg with pulmonary vascular resistance (PVR) ≥2 to \<3 WU and pulmonary arterial wedge pressure (PAWP) ≤15 mmHg or b) mPAP 21-\<25 mmHg with PVR ≥2 WU, and PAWP ≤15 mmHg associated with connective tissue disease (CTD) or as idiopathic/heritable form (see Group I / Nice Clinical Classification of Pulmonary Hypertension) (acc. to Simonneau et al. 2019). Patients with rheumatoid arthritis or connective tissue disease of any kind, except systemic lupus erythematosus, may also be included. Patients in group b will be mainly enrolled as long as patients in group a are not defined as having pulmonary arterial hypertension according to European pulmonary hypertension guidelines.
3. Treatment naïve patients (with respect to PAH specific medication)
4. Unspecific treatments which may also be used for the treatment of pulmonary hypertension such as oral anticoagulants, diuretics, digitalis, calcium channel blockers or oxygen supplementation are permitted. Permitted are also treatments of the rheumatologic disease. However, these drugs must have been started at least 1 month before right heart catheterization.
5. Right-heart catheterization results must not be older than 1 month at Visit 1 (will be considered as baseline values, the time frame can be prolonged up to 6 months, if the patient has had no signs of clinical changes defined as \>10% change of 6MWD, WHO FC, \> 30% change in NT-proBNP) and must have been measured in the participating center under standardized conditions (refer to the study specific Swan Ganz catheterization manual). If the respective measurements have not been performed in context with the patient's regular diagnostic work up, they have to be performed as a part of the study during the pre-study phase (after the patient signed the informed consent).
6. Women without childbearing potential defined as postmenopausal women aged 55 years or older, women with bilateral tubal ligation, women with bilateral ovariectomy, and women with hysterectomy can be included in the study.
7. Women of childbearing potential can only be included in the study if all of the following applies (listed below):

   1. Negative serum pregnancy test at screening and at study start (visit 1).
   2. Agreement to undertake monthly urine pregnancy tests during the study and up to at least 30 days after study treatment discontinuation. These tests should be performed by the patient at home.
   3. Agreement to use a highly effective contraception method as specified from screening until at least 30 days after last dose of study medication.
8. Patients who are able to understand and follow instructions and who are able to participate in the study for the entire period.
9. Patients must have given their written informed consent to participate in the study after having received adequate previous information and prior to any study-specific procedures.

Exclusion Criteria:

1. Patients with systemic lupus erythematosus.
2. Concomitant PAH-targeted treatment is not allowed during the study.
3. Concomitant treatment with phosphodiesterase 5 inhibitors, endothelin receptor antagonists and prostacyclin analogues due to digital ulcers is contraindicated and must not be taken during the study period. Such drugs must have a washout-phase of 3 days at the time of right heart catheterization at screening. Intravenous treatment with prostacyclin analogues should not be performed within 1 week of right heart catheterization. Any decision to discontinue above-mentioned drugs will be made by the clinicians and the patient at screening, which takes part during the patients' regular routine visit. The discontinuation of above-mentioned drugs will be evaluated by considering the presence or absence of digital ulcers and their frequency of appearance in the patient's medical history.
4. Pulmonary hypertension explained by other cause including group 2, 3, 4 and 5 PH according to the current guidelines.
5. Cardiac comorbidity, defined with three or more of the following conditions: uncontrolled arterial hypertension, diabetes mellitus, body mass index \>35, left atrial enlargement \>20 cm², atrial fibrillation, left ventricular ejection fraction \<50%.
6. Pulmonary comorbidity, defined as forced vital capacity (FVC) ≤70; forced expiratory volume in 1 second (FEV1) ≤50%; diffusion capacity of the lung (DLCO) ≤40%. FVC may be \<70/ if high resolution computed tomography shows \<20% lung fibrosis.
7. Patients with a medical disorder, condition, or history of such that would impair the patient's ability to participate or complete this study in the opinion of the investigator.
8. Patients with underlying medical disorders with an anticipated life expectancy below 2 years (e.g. active cancer disease with localized and/or metastasized tumor mass).
9. Patients with a history of severe or multiple drug allergies (defined as allergic reactions to three or more structurally unrelated drugs).
10. Patients with hypersensitivity to the investigational drug or any of the excipients.
11. Contraindications according to summary of product characteristics of riociguat (e.g. arterial hypotension with systolic blood pressure \<95 mmHg; nitrates)
12. Participation in any clinical drug trial within 4 weeks prior to screening of this study and/or patient, who is scheduled to receive an investigational medicinal product (IMP) during the course of this study
13. Background therapy with highly anti-fibrotic drugs (pirfenidone) or nintedanib, prednisolone \>10 mg/day

Where this trial is running

Graz and 7 other locations

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Pulmonary Vascular DisorderPrimary Pulmonary HypertensionSystemic SclerosisOther Systemic Involvement of Connective Tissueearly pulmonary vascular diseaseriociguatpulmonary hypertension
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.