Udenafil (Dosing Study)

Udenafil has been approved in several countries to treat erectile dysfunction in adult men. It has not yet been approved by the United States (U.S.) Food and Drug Administration (FDA) or Health Canada for use in North America. This means that Udenafil can only be used in research studies. This is the first Udenafil study in children or teens that have had Fontan surgery. We would like to learn about the possible benefit of Udenafil for children who have had a Fontan operation. However, we need to determine which dose of Udenafil is best. This study will help us to determine which dose we should use. This study enrolled 36 patients.

Who was in the study?

Males and females ages 14-18 years of age with Fontan physiology who agreed to participate in the study were enrolled.

What happened in the study?

Study participants took oral Udenafil at different dose levels for five days and completed the following assessments:

Medical Record Review: for information about surgeries, tests or times that you were in the hospital, medications and services such as physical or speech therapy.

Exercise Testing: to see how their heart functions during exercise. Study participants were asked to pedal on a stationary bike while various measurements of breathing, heart rate and blood pressure were taken.

Vascular Function Test (also called an EndoPAT): to assess function of blood vessels.

Echocardiograms and Blood Samples were also done.

What were the results of the study?

Udenafil was well-tolerated at all dosing levels. The 87.5 mg bid cohort achieved the highest plasma drug level and was associated with a suggestion of improvement in myocardial performance. The FUEL study (http://www.pediatricheartnetwork.org/Studies/CurrentStudies/FUELandFUELOLE.aspx) was designed to continue to evaluate the use of Udenafil in hundreds of participants after Fontan surgery.