Amanda Littleton

Growth factor plus preemptive ('just-in-time') plerixafor successfully mobilizes hematopoietic stem cells in multiple myeloma patients despite prior lenalidomide exposure

Lenalidomide is associated with suboptimal autologous hematopoietic stem cell (AHSC) mobilization. We hypothesized that growth factor plus preemptive plerixafor is an effective strategy for AHSC mobilization in multiple myeloma (MM) despite prior exposure to lenalidomide. We retrospectively reviewed patient characteristics and mobilization outcomes of 89 consecutive MM patients undergoing first mobilization with filgrastim or pegfilgrastim +/− preemptive plerixafor using a previously validated algorithm based on day 4 peripheral blood CD34+ cell count (PB-CD34+) and mobilization target. Outcomes were analyzed according to the extent of prior exposure to lenalidomide: no prior exposure (group A, n=40), 1– 4 cycles (group B, n=30) and >4 cycles (group C, n=19). Multivariate analysis yielded only age and number of cycles of lenalidomide as negatively associated, and mobilization with pegfilgrastim as positively associated with higher PB-CD34+. Only 45% of patients in group A required plerixafor vs 63% in groups B and 84% in C, P=0.01. A higher proportion of patients in group A (100%) met the mobilization target than in groups B (90%) or C (79%), P=0.008. All patients yielded at least 2 × 106 CD34+/kg. Growth factor mobilization with preemptive plerixafor is an adequate upfront mobilization strategy for MM patients regardless of prior exposure to lenalidomide.

Pegfilgrastim- versus filgrastim-based autologous hematopoietic stem cell mobilization in the setting of preemptive use of plerixafor: efficacy and cost analysis.

BACKGROUND: Plerixafor enhances the ability of filgrastim (FIL) to mobilize CD34+ cells but adds cost to the mobilization. We hypothesized that replacing weight‐based FIL with flat‐dose pegfilgrastim (PEG) in a validated cost‐based mobilization algorithm for patient‐adapted use of plerixafor would add convenience without increased cost.

Similar dynamics of intraapheresis autologous CD34+ recruitment and collection efficiency in patients undergoing mobilization with or without plerixafor

Compared with growth factor (G) alone, the combination of G with plerixafor (G + P) increases peripheral blood CD34+ count (PB‐CD34+) and improves CD34+ collection yield (yCD34+) in multiple myeloma and lymphoma patients undergoing autologous hematopoietic progenitor cell (AHPC) mobilization. It is unknown whether the improved yCD34+ with G + P results entirely from expansion of PB‐CD34+ or also from increased intraapheresis CD34+ recruitment and collection efficiency.