A Single-Arm, Open-Label Phase 1 Study of Itacitinib (ITA) with Calcineurin Inhibitor (CNI)-Based Interventions for Prophylaxis of Graft-Versus-Host Disease (GVHD; GRAVITAS-119)

Background Despite prophylaxis, GVHD remains a significant cause of morbidity and nonrelapse mortality after allogeneic hematopoietic cell transplantation (HCT). ITA is a potent, selective Janus kinase (JAK) 1 inhibitor that has been combined safely with steroids in patients (pts) with acute GVHD. We describe results from a proof-of-concept study evaluating ITA + CNI-based regimens for GVHD prophylaxis. Study Design and Methods GRAVITAS-119 (NCT03320642) was a single-arm, open-label study enrolling pts aged ≥18 y undergoing allogeneic HCT using peripheral blood stem cells from 8/8 or 7/8 matched related or unrelated donors for a hematologic malignancy. Eligible pts were candidates for reduc…