Rescue stem cell mobilization with plerixafor economizes leukapheresis in patients with multiple myeloma

Abstract

While extensive data demonstrated that plerixafor improves stem cell harvest in difficult-to-mobilize patients, economic concerns limit a broader application. We retrospectively assessed the effect of an early plerixafor rescue regimen for mobilization in patients with multiple myeloma. Patients were intended for high-dose chemotherapy followed by autologous peripheral blood stem cell transplantation (ABSCT) and therefore received cyclophosphamide-based mobilization chemotherapy and consecutive stimulation with granulocyte colony-stimulating factor (G-CSF). Fifteen patients with poor stem cell harvest in the first leukapheresis session received plerixafor. Data were compared with a matched historic control group of 45 patients who also had a poor stem cell yield in the first apheresis session, but continued mobilization with G-CSF alone. Patients in the plerixafor group collected significantly more CD34+ cells in total (median 4.9 vs. 3.7 [range 1.6-14.1 vs. 1.1-8.0] × 10(6) CD34+ cells /kg bw; P < 0.05), and also more CD34+ cells per leukapheresis procedure (P < 0.001). Consequently, they required a significantly lower number of leukapheresis procedures to achieve the collection goal (median 2.0 vs. 4.0 [range 2-3 vs. 2-9] procedures; P < 0.001). The efficiency of the collected stem cells in terms of hematologic engraftment after ABSCT was found to be equal in both groups. These data demonstrate that rescue mobilization with plerixafor triggered by a low stem cell yield in the first leukapheresis session is effective. Although the actual economic benefit may vary depending on the local leukapheresis costs, the median saving of two leukapheresis procedures offsets most of the expenses for the substance in this setting. An exemplary cost calculation is provided to illustrate this effect.

Plerixafor for Autologous Stem-Cell Mobilization and Transplantation for Patients in Ontario

“…This recommendation is supported by seven nonrandomized studies that reported a variety of outcomes, including number of stem cells collected and number of days of apheresis 10,11,13,15,16,24,27 . In general, those studies detected that a better mobilization response is achieved in patients failing their first mobilization attempt when plerixafor is added to their existing mobilization regimens.…”

“…Twenty-two studies assessing the efficacy and safety of plerixafor for autologous stem-cell mobilization and transplantation were retained: two randomized controlled trials (rcts) 6,7 , five nonrandomized controlled trials [8][9][10][11][12] , three retrospective cohort studies with a contemporaneous control arm [13][14][15] , and twelve single-arm studies [16][17][18][19][20][21][22][23][24][25][26][27] .…”

“…The five nonrandomized controlled trials [8][9][10][11][12] included fully described the inclusion and exclusion criteria, mobilization protocol, and outcomes of interest. Four of the studies compared outcomes with matched historical controls mobilized using a therapy that did not include plerixafor 8,9,11,12 .…”

“…Two comparative studies reported a statistically significant increase in the number of CD34+ cells collected (given here as millions per kilogram body weight) and in the median number of apheresis procedures for patients who received plerixafor compared with patients who received other regimens after primary mobilization failure 10,15 . In the retrospective comparative study reported by…”

“…The study by Hundemer et al 10 , in which data were matched with a historical control group on the basis of poor stemcell yield in the first apheresis session, reported a median CD34+ collection of 4.9 in 2 apheresis procedures with plerixafor and 3.7 in 4 apheresis procedures with g-csf (p = 0.01). The comparative study reported by Cheng et al 13 reported a median CD34+ collection of 8.5 for patients receiving plerixafor compared with 4.8 for patients not receiving plerixafor (p = 0.003), but the median number of apheresis procedures was not reported.…”