Tacrolimus/Everolimus vs. Tacrolimus/MMF in Pediatric Heart Transplant Recipients Using the MATE Score

Inclusion Criteria:

   1. Orthotopic heart transplantation

   2. Age < 21 years at time of transplant

   3. Stable immunosuppression at the time of randomization with no contraindication to
   everolimus, tacrolimus, or mycophenolate mofetil

   4. Planned follow-up at a study site for the 30 month duration of the study.

   5. Subject or legal adult representative capable of providing informed consent (in
   general, assent will be sought for children aged 12 years or older).

Exclusion Criteria:

   1. Multi-organ transplant (e.g. heart-lung or heart-liver).

   2. Known hypersensitivity to everolimus, sirolimus, tacrolimus or mycophenolate mofetil
   (MMF), or to components of the drug products.

   3. Patients on maintenance corticosteroid therapy exceeding a dose equivalent of
   prednisone 0.1 mg/kg/day at randomization.

   4. High-risk for rejection defined as active rejection, recurrent (≥ 2 episodes of grade
   2R rejection) cellular rejection, recurrent rejection (≥ 2 episodes of any grade) with
   hemodynamic compromise, steroid-resistant rejection or unresolved antibody-mediated
   rejection during the first 6 months post-heart transplant

   5. Graft dysfunction (LVEF <40% or wedge pressure >22 mmHg or cardiac index <2.2
   L/min/m2)

   6. Stage 4 or 5 CKD (eGFR <30 ml/min/1.73 m2)

   7. Moderate or severe proteinuria

   8. Active infection requiring hospitalization or treatment dose medical therapy.

   9. Patients with ongoing wound healing problems, clinically significant wound infection
   requiring continued therapy or other severe surgical complication in the opinion of
   the Site Principal Investigator.

10. Fasting Serum Cholesterol ≥300 mg/dL OR greater than or equal to 7.75 mmol/L, AND
   fasting triglycerides ≥2.5x the upper limit of normal (ULN). Note: In case one or both
   of these thresholds are exceeded, the patient can only be included after initiation of
   appropriate lipid lowering medication, and reduction of serum cholesterol and
   triglyceride levels to below exclusion ranges is confirmed.

11. Uncontrolled diabetes mellitus.

12. Diagnosis of post-transplant lymphoproliferative disorder (PTLD) during the first 6
   months post-heart transplant.

13. History of non-adherence to medical regimens.

14. Patients who are treated with drugs that are strong inducers or inhibitors of
   cytochrome P450 3A4 (CYP3A4) and cannot discontinue the treatment

15. Patients who are pregnant or breast-feeding or intend to get pregnant during the study
   period.