Acute GVHD: think before you treat.

The treatment of acute graft-versus-host disease (aGVHD) has become more nuanced in recent years with the development of improved risk classification systems and a better understanding of its complex, multisystem pathophysiology. We review contemporary approaches to the risk stratification and initial treatment of aGVHD, including ongoing clinical trials. We summarize the findings that led to the first US Food and Drug Administration approval for steroid-refractory aGVHD (SR-aGVHD), ruxolitinib, as well as some of the challenges clinicians still face in treating SR-aGVHD. Finally, we discuss the evaluation and management of steroid-dependent aGVHD, which affects approximately one-third of patients who have long-term, waxing and waning symptoms distinct from chronic GVHD. Future clinical trials for aGVHD treatment may identify steroid-sparing approaches for patients who have a high likelihood of response and approaches to improve tissue repair and dysbiosis for those unlikely to respond to immunosuppression alone.