RIC alloBMT With Post-transplant Cyclophosphamide for Refractory Systemic Sclerosis

This is a Phase I, single arm, open label, single center pilot study to assess a reduced-intensity conditioning regimen, bone marrow transplantation with high dose cyclophosphamide (PTCy) in recipients with refractory systemic sclerosis. This study expects to enroll 15 donor/recipient pairs for a total of 30 participants. The primary objective of this study is to assess the safety of using a reduced intensity condition (RIC) preparative regimen bone marrow transplant (BMT) with post-transplant cyclophosphamide for graft vs host disease (GVHD) prophylaxis as treatment for patients with scleroderma. Safety events are grade III-IV GVHD and treatment related mortality within 1 year. Eligibility includes patients \>18 years who are eligible for transplantation according to the BMT Policy Manual, meet the 2013 ACR/EULAR Criteria for Systemic Sclerosis and display active diffuse cutaneous disease. The trial also includes analyses of the effects of BMT on skeletal and cardiac muscle using systemic scleroderma serum biomarkers of CK, aldolase, and troponin as well as periodic monitoring of circulating scleroderma auto-antibody titers, autoreactive T cells, and flow cytometric signatures over the one-year study period to correlate with response.