Aplastic anemia is a potentially lethal autoimmune disease where the immune system erroneously targets and destroys bone marrow stem cells. Treatments such as immunosuppression or bone marrow transplantation are effective but have serious side effects. A patient presented to our hospital with aplastic anemia due to a mutation in STAT1, a gene involved in immune system function. Patients with other conditions caused by STAT1 mutations have been successfully treated with JAK inhibitors—a class of medications associated with fewer side effects. Our patient was treated with the JAK inhibitor itacitinib, which resulted in resolution of his aplastic anemia. Our data suggest that other patients with aplastic anemia also have STAT1 activation and may also benefit from JAK inhibitor treatment.
JAK inhibition in a patient with a STAT1 gain-of-function variant reveals STAT1 dysregulation as a common feature of aplastic anemia