Conditions: Single Ventricle Heart Disease After Fontan Surgery
Keywords: Fontan Pharmacokinetics Pharmacodynamics Exercise capacity Maximal Oxygen Consumption Vascular function EndoPAT Myocardial performance
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 36
Healthy volunteers: no

Brief summary:
To determine the pharmacokinetic profile and safety of udenafil in adolescents with Fontan physiology and to assess the short-term pharmacodynamic effect of udenafil on pharmacodynamic measures of exercise capacity, ventricular performance, and vascular function.

Detailed description:
A dose escalation trial to determine the pharmacokinetics, safety and tolerance of udenafil in male and female adolescent subjects with single ventricle physiology that that have undergone the Fontan surgical procedure. Pharmacodynamic data will also be collected to evaluate the effect of udenafil on acute exercise performance, peripheral vascular function and indices of myocardial performance. Five udenafil cohorts will be evaluated in additional to one drug free cohort

Arms:
arm 1: Udenafil 37.5 mg tablet once daily for 5 days arm 2: Udenafil 37.5 mg tablet twice daily for 5 days arm 3: Udenafil 87.5 mg tablet once daily for 5 days arm 4: Udenafil 87.5 mg tablet twice daily for 5 days arm 5: Udenafil 125 mg tablet once daily for 5 days arm 6: Cohort undergoing exercise test only

Interventions: intervention 1: Udenafil
Intervention descriptions: intervention 1: Drug

Protocol document: