Salvage treatment with plerixafor in poor mobilizing allogeneic stem cell donors: results of a prospective phase II-trial
Kristina Hölig, Helmuth Schmidt, Gero Hütter, Michael Krämer, Raphael Teipel, Katharina Heidrich, Kristin Zimmer, Falk Heidenreich, Matthias Blechschmidt, Tigran Torosian, Rainer Ordemann, Frank Kroschinsky, Elke Rücker‐Braun, Laszlo Gopsca, Eva Wagner-Drouet, Uta Oelschlaegel, Alexander H. Schmidt, Martin Bornhäuser, Gerhard Ehninger, Johannes Schetelig
Abstract
Abstract We conducted a prospective clinical trial to investigate the safety and efficacy of plerixafor (P) in allogeneic peripheral blood stem cells (PBSC) donors with poor mobilization response to standard-dose granulocyte colony-stimulating factor (G-CSF), defined by <2 × 10 6 CD34 + cells/kg recipient body-weight (CD34+/kg RBW) after 1st apheresis. A single dose of 240 µg/kg P was injected subcutaneously at 10 p.m. on the day of the 1st apheresis. Thirty-seven allogeneic PBSC donors underwent study treatment. The median CD34+ count in peripheral blood was 15/µl on Day 1 after G-CSF alone, versus 44/µl on Day 2 after G-CSF plus P ( p < 0.001). The median yield of CD34+ cells was 1.1 × 10 8 on Day 1 and 2.8 × 10 8 on Day 2. In contrast to a median yield of only 1.31 × 10 6 CD CD34+/kg RBW on Day 1, triggering study inclusion, a median of 3.74 × 10 6 CD CD34+/kg RBW were collected with G-CSF plus P on Day 2. Of 37 donors, 21 reached the target cell count of >4.5 × 10 6 CD34+/kg RBW (57%, 95%CI 40–73%). No donor experienced a severe adverse event requiring treatment. In conclusion, P might be considered on a case-by-case basis for healthy allogeneic donors with very poor stem cell mobilization success after G-CSF.