Recruiting
Phase 3

Tadalafil

Sponsor:

Mayo Clinic

Code:

NCT05206955

Conditions

Fontan Palliation

Eligibility Criteria

Sex: All

Age: 18+

Healthy Volunteers: Not accepted

Interventions

Tadalafil

Placebo

Study Details

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

Study ID

NCT05206955

Start date

Sep 16, 2022

Status verified date

Aug, 2026

Completion date

Nov, 2026

Anticipated

Primary completion date

Nov, 2026

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 18+

Healthy Volunteers: Not accepted

Inclusion Criteria:

  • 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

Exclusion Criteria:

  • 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.

Study Design

Enrollment

42 participants

Anticipated

Allocation

Randomized

Intervention Model

Parallel Assignment

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

experimental: Tadalafil Group

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.

placebo comparator: Placebo Group

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.

Interventions

Tadalafil

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

Placebo

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

Primary outcome measure

  • Microvascular endothelial function [ Time Frame: 52 weeks ]
  • Pulmonary vascular reserve [ Time Frame: 52 weeks ]

Central Contacts and Locations

Central contacts

ACHD Research Team

507-293-2565RSTACHDRESPRG@mayo.edu

Locations

Mayo Clinic

Recruiting

Rochester, Minnesota, United States, 55905

Contacts

ACHD Research Team

507-293-2565RSTACHDRESPRG@mayo.edu

Principal Investigator:

Alexander C Egbe, MBBS, MPH

More Information

Sponsor

Mayo Clinic

Last update posted

Aug 13, 2026

Last verified

Aug, 2026

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by Mayo Clinic on 2026-08-13.