Design & Procedures~All patients will undergo allogeneic stem cell transplantation (HCT) according to the program's standards. No specific conditioning regimen is mandated. The stem cell source must have been peripheral blood stem cells. Prophylaxis against acute GVHD must be with standard agents (sirolimus and/or tacrolimus and/or methotrexate and/or cyclosporine). Participation in a trial evaluating novel agents for therapy of acute GVHD is allowed, as long as the experimental agent was discontinued > 14 days prior to trial entry.~Therapy: Patients will receive 100mg daily, 150mg daily or 100 mg bid beginning 90 days after allogeneic transplantation and continue for up to 1 year from day of transplant OR beginning at time of steroid-refractory cGVHD. Dosage will be determined using the modified continual reassessment method.~Patient evaluations: Patients will be evaluated for cGVHD and other toxicity at a minimum on day 1(baseline), day 3, day 11, day 25, day 39, day 60, day 88, day 116, day 144, day 186, day 228, and day 275 from initiation of protocol therapy. While the assessment for safety is determined based on the evaluation at day 60, patients may stay on therapy for up to 1 year after transplantation (study treatment day 275). In addition, patients will be observed for one year after stopping study treatment with evaluation for toxicity and cGVHD during clinic visits at 6 and 12 months after completion of study therapy. If at any time within the first year after transplantation, a study subject is determined to have evidence of moderate or severe stage cGVHD according to NIH consensus criteria for global severity, the subject will be removed from this clinical trial and appropriate therapy for cGVHD will be administered per the treating physician's discretion. The study subject may continue to receive Fostamatinib as per the guidelines of this clinical trial in the event that mild stage cGVHD is diagnosed. If cGVHD develops during the observation period, a second course of Fostamatinib at 100% tolerated study dose may be given during the observation period.~Immunosuppressive and other medications should be tapered according to the treating physicians' discretion with careful attention to the clinical trial or treatment plan to which the participating subject is already enrolled.~Laboratory samples will be obtained according to the study schedule. The following tests are to be collected and analyzed for the study: complete blood counts, serum chemistry, liver function tests (LFTs), chimerism analysis if indicated, and immunology/correlative science studies.~This study will be open to members of all demographic groups who meet the eligibility criteria. Approximately 18 subjects will be recruited at Duke.~A total of eighteen patients will receive fostamatinib beginning at day 90 after allogeneic transplantation. The safety assessment is determined at day 60. Patients with steroid-refractory cGVHD are also eligible for this phase I study. Three dose levels are considered: 100 mg qd, 150 mg qd, 100 mg bid, and the target dose-limiting toxicity (DLT) probability is 0.33. The Bayesian model averaging continual reassessment method (BMA-CRM) will be used for this trial.[15]~The investigators will study targeted molecular mechanisms underpinning aberrant B-cell signaling in cGVHD. Corollary studies will determine whether B and T cell subsets and/or soluble B-cell activation factors are altered after Syk inhibition. The objective is to implement preemptive targeted therapies that decrease excessive immune activation in patients.
The purpose of this study is to evaluate whether fostamatinib, a drug that blocks activated B cells will be effective in preventing and treating chronic graft vs host disease (cGVHD) after allogeneic stem cell transplant. Activated B cells may play a role in development of cGVHD. Inhibiting the B cell activation using fostamatinib after allogeneic stem cell transplant may prevent the development of cGVHD.