Patients with
multiple myeloma (MM) scheduled for autologous
stem cell transplantation must undergo autologous
stem cell mobilization; unfortunately, however, many do not obtain an adequate collection yield. Despite the availability of
plerixafor, its widespread and uniform use is limited by its cost, and consequently, many institutions have adopted various risk-adapted algorithms. We report our mobilization experience as we have modified our
plerixafor algorithm to a more liberal one, with the expectation of greater collection efficiency and mobilization success with higher
plerixafor use. A total of 344 mobilization attempts were analyzed over 3 time periods and using 3 different peripheral blood CD34+ cell counts to guide
plerixafor use: <15/µL (n = 66), <20/µL (n = 130), and <40/µL (n = 148). The primary endpoints were evaluation of changes in mean
plerixafor utilization and
apheresis days and assessment of the impact on overall mobilization costs. Secondary endpoints were a description of the impact of
lenalidomide use on mobilization and evaluation of the rate of mobilization failure. We found that mean
plerixafor use increased from 1.32 to 1.65 to 1.74 doses per mobilization (P = .026) and the mean days of
apheresis decreased from 2.15 to 2.17 to 1.89 days per mobilization for the <15/µL, <20/µL, and <40/µL cohorts, respectively (P = .011). The combined cost of
plerixafor and
apheresis procedures at a threshold of 40/µL is close to that at a threshold of 15/µL, while saving 26
apheresis days per 100 patients. In general, there were low rates of mobilization failure across all thresholds. Patients who received more than 6 cycles of
lenalidomide demonstrated impaired mobilization and required more
apheresis sessions (P < .013) and greater
plerixafor use (P < .001) to achieve target stem cell yields. Overall, using
plerixafor in patients with MM, with a day 4 pCD34 count of <40/µL is a reasonable and cost-effective strategy to optimize
apheresis utilization.