Study of Tadalafil vs. Placebo for Improving Hemodynamics and End-Organ Dysfunction in Fontan Physiology

NCT05206955 | Recruiting Phase 3 FDA Drug

• 2 other identifiers: 21-009890R01HL160761-01
• Study Type: interventional
• Target: 80
• Locations: 1 country
• Sites: 1

Brief Summary

The purpose of this study is to find out more about the effectiveness of Tadalafil in improving hemodynamic capabilities, endothelial function, and end-organ function in patients who have previously undergone a Fontan Palliation.

Conditions

Fontan Palliation

Outcome Measures

Primary Outcomes (2)

• Microvascular endothelial function

  Measured by the reactive hyperemic index using peripheral artery tonometry (EndoPAT)

  52 weeks

• Pulmonary vascular reserve

  The slope of mean pulmonary artery pressure / cardiac output (mPAP/CO)

  52 weeks

Secondary Outcomes (4)

• Liver stiffness

  52 weeks

• Renal function

  52 weeks

• Exercise capacity

  52 weeks

• Patient reported quality of life

  52 weeks

Study Arms (2)

Tadalafil Group

EXPERIMENTAL

Study participants will receive 10 mg of Tadalafil daily for 1 week, then 20 mg daily for 1 week, and finally 40 mg daily for 50 weeks for a total therapy time of 52 weeks. Tadalafil will be taken orally in capsule form once daily.

Drug: Tadalafil

Placebo Group

PLACEBO COMPARATOR

Study participants will receive a placebo capsule that looks identical to the Tadalafil capsule. The placebo will be taken orally once daily for 52 weeks.

Drug: Placebo

Interventions

Tadalafil DRUG

10 mg once daily orally week 1, 20 mg once daily orally during week 2, and 40 mg once daily orally during weeks 3 through 52

Tadalafil Group

Placebo DRUG

Looks exactly like the study drug, but it contains no active ingredient

Placebo Group

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Patients ≥ 18 years old.
• Have previously undergone a Fontan Palliation.
• Able to exercise using a supine bike.
• Ability and willingness to provide written consent.
• Undergoing a clinically indicated Cardiac Catheterization

You may not qualify if:

• Patients \< 18 years old.
• Current intravenous inotropic drugs.
• Current use of alpha-blockers, pulmonary vasodilators, or nitrates.
• Unable to exercise.
• Pregnancy or lactating.
• Unable or unwilling to consent.

Sponsors & Collaborators

• Mayo Clinic: lead
• National Heart, Lung, and Blood Institute (NHLBI): collaborator

Study Sites (1)

Mayo Clinic

Rochester, Minnesota, 55905, United States

RECRUITING

MeSH Terms

Interventions

Tadalafil

Intervention Hierarchy (Ancestors)

Carbolines; Pyridines; Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds; Indole Alkaloids; Indoles; Heterocyclic Compounds, 2-Ring; Heterocyclic Compounds, Fused-Ring; Heterocyclic Compounds, 3-Ring

Study Officials

• Alexander C Egbe, MBBS, MPH

  Mayo Clinic

  PRINCIPAL INVESTIGATOR

Central Study Contacts

ACHD Research Team

CONTACT

507-293-2565; RSTACHDRESPRG@mayo.edu

Study Design

• Study Type: interventional
• Phase: phase 3
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, INVESTIGATOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal Investigator

Study Record Dates

• First Submitted: January 12, 2022
• First Posted: January 25, 2022
• Study Start: September 16, 2022
• Primary Completion (Estimated): November 1, 2026
• Study Completion (Estimated): November 1, 2026
• Last Updated: November 14, 2025

Record last verified: 2025-11

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)