Vorinostat for Graft-versus-host Disease (GVHD) Prevention in Non-Malignant Adolescent and Young Adults (AYA) Population

This is a single-arm, open label, phase 2 study to determine the safety and efficacy of vorinostat without serotherapy as GVHD prophylaxis when combined with either tacrolimus and methotrexate or post-transplant cyclophosphamide, tacrolimus, and mycophenolate in patients aged 1 to 26 years of age with non-malignant disorders undergoing bone marrow transplant following myeloablative conditioning.

Inclusion Criteria: * Non-malignant condition amenable to transplantation, including but not limited to: 1. Primary Immunodeficiency/Primary Immune regulatory disorders 2. Inborn errors of metabolism 3. Red blood cell disorders including hemoglobinopathies per protocol. 4. Inherited bone marrow failure syndromes * Available donor per protocol (matched siblings and matched unrelated donors, haploidentical donors). The use of mismatched unrelated donors will not be allowed for this study. * Patient and/or legal guardian have signed the informed consent document * Adequate organ function and performance status for allogeneic hematopoietic stem cell transplantation as defined by institutional practice: 1. Pulmonary Function: diffusing capacity of the lungs for carbon monoxide (DLCO), forced expiratory volume in the first second (FEV1), Forced vital capacity (FVC) ≥50% predicted. 2. Renal Function: Estimated or actual glomerular filtration rate (GFR) of ≥50 milliliters per minute (mL/min)/1.72 square meter (m2) 3. Liver Function: aspartate aminotransferase (AST), alanine aminotransferase (ALT) \8 milligram (mg) Iron(Fe)/Gram dry weight or evidence of bridging fibrosis or cirrhosis on biopsy. * Patients enrolled on another GVHD-prevention clinical trial. * Patients receiving an ex-vivo T cell-depleted or cluster of differentiation (CD34)-selected stem cell graft. * Subjects that have had prior treatment with a histone deacetylase inhibitor (e.g. vorinostat, valproic acid) within the last 30 days. * History of prolonged corrected QT interval (QTc) syndrome. * Uncontrolled intercurrent illness including, but not limited to, symptomatic congestive heart failure, unstable angina pectoris, cardiac arrhythmia, or psychiatric illness/social situations that would limit compliance with study requirements