Ibrutinib for the Prevention of Chronic Graft-Versus-Host Disease in Patients Undergoing Donor Stem Cell Transplant

Inclusion Criteria: * 50 to 110 days post-transplant prior to registration * Age ≥ 18 years * HLA matched-related, matched unrelated donors (defined as 8/8 \[class I: HLA A, B, C, and class II: DRB1\]), or HLA-mismatched-unrelated donors (defined as 7/8 \[with single mismatch at class I: HLA A, B, C, or class II: DRB1\]) * Karnofsky performance status (PS) ≥ 70 * Hemoglobin ≥ 8.0 g/dL (untransfused) (obtained ≤ 7 days prior to registration) * Absolute neutrophil count (ANC) ≥ 1000/mm\^3 (without growth factor support) (obtained ≤ 7 days prior to registration) * Platelet count ≥ 50,000/mm\^3 (untransfused) (obtained ≤ 7 days prior to registration) * Prothrombin time (PT)/international normalized ratio (INR)/activated partial thromboplastin time (aPTT) ≤ 1.5 x upper limit of normal (ULN) (obtained ≤ 7 days prior to registration) * Total bilirubin ≤ 1.5 x ULN (unless it is due to Gilbert's syndrome or causes other than liver) OR alanine aminotransferase (ALT) and aspartate transaminase (AST) ≤ 2 x ULN (unless it is due to Gilbert's syndrome or causes other than liver) (obtained ≤ 7 days prior to registration) * Calculated creatinine clearance ≥ 40 ml/min using the Cockcroft-Gault formula (obtained ≤ 7 days prior to registration) * Adequate cardiac and pulmonary function at baseline (may be based on pre-transplant vital organ work up): * Cardiac evaluation to determine left ventricular ejection fraction (LV-EF) if there is any clinical reason (for example an ischemic event or…