Impact of EPAG on HSPC frequency. The frequencies of CD34⁺/CD38^– primitive HSPCs, CD34⁺/CD38⁺ maturing HSPCs, and total CD34⁺ HSPCs within bone marrow mononuclear cells is shown for 12 responding (A) and 10 nonresponding (B) patients. P values for paired Student t tests comparing baseline (Pre) and primary end point (Post) are given. *P < .05.