Multicenter FUEL-2 Study for Adolescent Fontan Patients Beginning at UPMC Children’s

The Heart Institute at UPMC Children's Hospital of Pittsburgh is a participating center in the FUEL-2 study, a new multicenter, prospective clinical trial that aims to evaluate the efficacy of udenafil, a PDE5 inhibitor, in comparison to a placebo in adolescent patients who have undergone the Fontan procedure.

Tarek Alsaied, MD, FACC, MSc, is the site principal investigator for the trial at UPMC Children's.

VO2 in Fontan Patients – Clinical Significance

For patients with a Fontan circulation, peak oxygen consumption (VO2) is a critical measure of cardiovascular fitness and overall functional capacity. The Fontan procedure, a palliative surgical technique for children with single-ventricle heart defects, reroutes venous blood directly to the pulmonary arteries, bypassing the heart. While life-saving, this procedure often results in reduced exercise tolerance and increased risk of heart failure. Measuring VO2 provides valuable insights into a patient's aerobic capacity and can help guide clinical management to improve long-term outcomes.

FUEL-2 Study Details

The FUEL-2 study builds on the findings of the earlier FUEL-1 study. Although FUEL-1 suggested a trend towards statistical significance in improving peak VO2 (p=0.08), it included a significant number of patients with a baseline peak VO2 greater than 80%, potentially diluting the results. A subanalysis of FUEL-1, which excluded these high-capacity patients, demonstrated a statistically significant improvement in VO2 even with a smaller cohort, establishing the safety of udenafil.

General Eligibility Requirements for the Study

Fontan patients aged 12-18 years of age are eligible for enrollment in the study and who meet the other inclusion criteria, including the following:

• Must be on antiplatelet or anticoagulant therapy.
• No use of PDE5 inhibitors in the last 12 months.
• Baseline VO2 between 45% and 80%.

Study Design and Participation – Information for Referring Physicians

The FUEL-2 study requires only two in-person visits at the beginning and end of the 26-week trial period. Each visit includes a bicycle exercise test with a metabolic cart and blood work. Participants will be randomly assigned to receive either udenafil or a placebo, with close monitoring for adverse events and medication compliance for the duration of the study.

Families participating in the study will receive compensation and reimbursement for any travel expenses incurred to support participation and ensure that logistical challenges do not hinder involvement in the study.

For additional information or to refer a patient, please contact Shannon Janzef, MSN, RN, CBC, Lead Clinical Research Coordinator at 412.692.5760.

Study Reference and Protocol
Fontan Udenafil Exercise Longitudinal Assessment Trial – 2 (FUEL-2). ClinicalTrials.gov identifier: NCT05918211. Status: Recruiting.