A Long-term Extension Study of Riociguat in Patients With Symptomatic Pulmonary Arterial Hypertension. (RIALTO)

October 2, 2025 updated by: Bayer

An Open-label, Multi-national, Multi-center, Single-arm, Uncontrolled, Long-term Extension Study of Orally Administered Riociguat in Patients With Symptomatic Pulmonary Arterial Hypertension (PAH) Who Received Riociguat in a Bayer Clinical Trial

To provide riociguat therapy to eligible patients with PAH originating from Bayer-sponsored trials with BAY63-2521/ Riociguat / Adempas® who are currently or recently treated in these trials until lack of patient benefit as assessed by investigator, or commercial availability and reimbursement.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Study Type

Interventional

Enrollment (Actual)

18

Phase

  • Phase 4

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • France
      • Besançon, France, 25030
      • Brest, France, F-29609
      • Le Kremlin-Bicêtre, France, 94275
      • Lille, France, 59037
      • Rouen, France, 76031
  • South Korea
      • Seoul, South Korea, 06351
    • Seoul Teugbyeolsi
      • Seoul, Seoul Teugbyeolsi, South Korea, 03722
      • Seoul, Seoul Teugbyeolsi, South Korea, 05505
      • Seoul, Seoul Teugbyeolsi, South Korea, 3080

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Patients diagnosed with Pulmonary Arterial Hypertension (PAH) participating or having participated in the Bayer-sponsored studies 12935, 16719 or 18588, who have completed the main study phase and are still being treated with riociguat (either while still being on treatment with the respective study drug or by commercial means with Adempas) and who, in the opinion of the investigator, are expected to continue to have an overall positive benefit/risk from continuing treatment.
  • Women and men of reproductive potential must agree to use adequate contraception when sexually active. This applies for the time period between signing of the informed consent form and 30 days after the last administration of study drug.

Exclusion Criteria:

  • Ongoing serious adverse event (SAE) from originating study that is assessed as related to riociguat
  • Pregnant women or breast-feeding women
  • Any contra-indication to Adempas treatment listed in the BAY63-2521 / Riociguat Investigators's Brochure
  • Concomitant participation in another clinical study with the study drug
  • Patients with pulmonary hypertension associated with idiopathic interstitial pneumonia (PH-IIP)

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: N/A
  • Interventional Model: Single Group Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: BAY63-2521
Single-arm, uncontrolled
Drug: Adempas (Riociguat, BAY63-2521)
0.5 to 2.5 mg in 0.5 mg increments (according to individual adapted optimal dose determined in originating study) administered three times daily (tid)

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Time Frame
Number of patients with treatment-emergent adverse events (TEAEs) as measure of safety and tolerability
Time Frame: Up to approx. 3 years
Up to approx. 3 years

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Bayer

Investigators

  • Study Director: Bayer Study Director, Bayer

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

Helpful Links

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

June 16, 2016

Primary Completion (Actual)

September 15, 2025

Study Completion (Actual)

September 15, 2025

Study Registration Dates

First Submitted

April 29, 2016

First Submitted That Met QC Criteria

April 29, 2016

First Posted (Estimated)

May 3, 2016

Study Record Updates

Last Update Posted (Estimated)

October 3, 2025

Last Update Submitted That Met QC Criteria

October 2, 2025

Last Verified

October 1, 2025

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 18694
  • 2016-000501-36 (EudraCT Number)

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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