Imatinib and Rituximab in Treating Cutaneous Sclerosis in Patients With Chronic Graft-Versus-Host Disease

PRIMARY OBJECTIVES: I. To determine the best clinical response rate of cutaneous sclerosis (skin and/or fascial thickening) after 6 months of initial therapy with either imatinib (imatinib mesylate) or rituximab. SECONDARY OBJECTIVES: I. To determine the best response at either the 3 or 6 month assessment. II. To determine the response rate at the 3 month assessment. III. To determine the proportion of subjects who are able to taper corticosteroid after 6 months of imatinib or rituximab therapy. IV. To determine the incidence of treatment failure to initial treatment with either imatinib or rituximab. V. To evaluate if the Scleroderma Health Assessment Questionnaire (SHAQ) findings correlate with severity of cutaneous sclerosis clinical findings and response to study treatment. VI. To correlate the detection of antibody against platelet derived growth factor receptor alpha (PDGFR A) with clinical response. VII. To correlate change in B cell relevant parameters from baseline to 6 months or early crossover (antibody levels, skin collagen expression, B cell subsets) with therapeutic agent and best clinical response while on initial treatment. OUTLINE: Patients are randomized to 1 of 2 treatment arms. ARM I: Patients receive imatinib mesylate by mouth (PO) once daily (QD) for 6 months in the absence of progression of sclerosis or unacceptable toxicity. Subjects with a significant clinical response will continue to receive study drug for an additional 6 months. ARM II: Patients receive rituximab intravenously (IV) on days 1, 8, 15, and 22 (first cycle). A second cycle of treatment with rituximab is repeated at 3 months for a total of 8 doses of rituximab in the absence of progression of sclerosis or unacceptable toxicity. Patients with progression, treatment intolerance at any time up to 6 months, or no clinical response at 6 months will crossover to the other treatment arm.