Upfront Ruxolitinib for Chronic Graft-vs-host Disease

Inclusion Criteria: * Newly diagnosed moderate to severe chronic graft versus host disease (as defined by NIH cGVHD consensus criteria), requiring systemic treatment * Patient aged ≥12 year-old and ≤30 year-old * Patient able to take oral or enteral medication * No active, clinically significant uncontrolled infections * ALT ≤ 5x upper limit of normal (ULN) and total bilirubin ≤ 5xULN (unless presumed liver GVHD) * Platelet ≥ 20k and ANC ≥ 500. The use of transfusions or growth factors is permitted to maintain counts at these thresholds * No prior systemic treatment for chronic GVHD. Patients previously treated for acute GVHD are eligible, including those who received ruxolitinib for treatment of their aGVHD * Patients must be on ≤ physiologic dosing (i.e. hydrocortisone 8-12mg/m2/day) at enrollment * Patients with prior acute GVHD on \< 1 mg/kg steroids with new onset moderate-severe chronic GVHD may be considered for enrollment if they can taper steroids to reach physiological hydrocortisone in 1 month. If unable to do so these patients will come off study and be replaced Exclusion Criteria: * Mild cGVHD (as defined by NIH cGVHD consensus criteria11), that does not require systemic therapy * Acute or late acute GVHD without any evidence of chronic GVHD features * Patients who have received corticosteroids for ≥ 24 hours at 1 mg/kg/day of methylprednisolone or prednisone with the intent to treat cGVHD at time of enrollment * Corticosteroid dosing above physiologic dose hydrocortisone (i.e. \> 8-12mg/m2/day) at time of enrollment * Clinical evidence suggesting active malignancy (including PTLD and primary/secondary malignancy) * Clinical evidence of clinically significant active infection * Ongoing cytopenias which cannot be supported with routine supportive care (keeping hemoglobin over 7 g/dL and platelets \>20,000 and absolute neutrophil count over 500/uL) * Active lower gastrointestinal bleeding * Thrombosis within 6 months (including myocardial infarction, stroke, deep venous thrombosis, pulmonary embolism). IV infiltration will not be included as an example of thrombosis * Pregnant or lactating females; patients of childbearing age who are not able to comply with contraceptive recommendations * Other condition that PI feels would preclude the patient from complying with study activities * ESRD \[CLcr \< 15 mL/min\] not on dialysis * Overlap syndrome