CD34 and VEXAS syndrome: Building on these findings, for this study, we obtained primary bone marrow samples from patients with VEXAS syndrome (n = 5) and MDS (n = 10) as well as healthy, age‐matched controls (n = 10) from femoral heads after hip replacement surgery, and conducted in vitro testing of TAK‐243 and pevonedistat on primary CD34+ cells to explore their clinical activity.