Belumosudil for the Pre-emptive Treatment of Patients With Chronic Graft Versus Host Disease

Inclusion Criteria: * At least one diagnostic or distinctive cGVHD manifestation(s), with a clinical diagnosis of cGVHD,but patients do not need to meet National Institute of Health (NIH) criteria for cGVHD * If eye involvement only, cGVHD must be confirmed on exam by an ophthalmologist or optometrist * No new immune suppressive therapy added within preceding 2 weeks prior to study enrollment for any indication * Continuation of agents previously given as either GVHD prophylaxis or acute/late acute GVHD therapy are permitted. Modification of dose of these agents for targeting of therapeutic drug levels is permitted, as are decreases in existing prednisone or prednisone equivalent dose based on routine clinical tapering practices. Increases in prednisone or prednisone equivalents are not allowed in the 2 weeks prior to enrollment * Age 18 and older * Karnofsky performance score \>= 70 * Able to take oral medications * Signed informed consent * Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) =\< 3 x upper limit of normal (ULN) * Total bilirubin =\< 1.5 x ULN, unless due to Gilbert's disease * Glomerular filtration rate (estimated glomerular filtration rate \[eGFR\]) \>= 30 mL/min/1.73 m\^2 * Female subjects of childbearing potential have a negative serum or urine pregnancy test at screening. Females of childbearing potential are defined as sexually mature females without prior hysterectomy or who have had any evidence of menses in the past 12 months. How…