Comparable efficacy and lower cost of PBSC mobilization with intermediate-dose cyclophosphamide and G-CSF compared with plerixafor and G-CSF in patients with multiple myeloma treated with novel therapies

Studies comparing the efficacy and cost of stem cell mobilization with intermediate-dose CY (ID-CY) and G-CSF against plerixafor and G-CSF, specifically in multiple myeloma (MM) patients treated in the novel therapy era, are not available. Eighty-eight consecutive patients undergoing mobilization with ID-CY (3-4 g/m 2) and G-CSF (n=55) were compared with patients receiving plerixafor and G-CSF (n=33). Compared with plerixafor, ID-CY use was associated with higher median peak peripheral blood CD34+ cell count (68 vs 160 cells/μL, P<0.001), and CD34+ cell yield on day 1 of collection (6.9 × 10 6 vs 11.7 × 10 6 cells/kg, P<0.001). Total CD34+ cell yield was significantly higher in the ID-CY patients (median collection 16.6 × 10 6 vs 11.6 × 10 6 cells/kg; P<0.001). ID-CY use was associated with significantly more frequent episodes of febrile neutropenia (16.3% vs 0%; P=0.02), intravenous antibiotic use (16.3% vs 3%; P=0.03) and hospitalizations (P=0.02). The average total cost of mobilization in the plerixafor group was significantly higher compared with the ID-CY group ($28 980 vs $22 504.8; P=0.001). Our data indicate robust stem cell mobilization in MM patients treated with novel agents, with G-CSF and either ID-CY or plerixafor. When compared with plerixafor, ID-CY-containing mobilization was associated with significantly lower average total mobilization costs.