The effective use of plerixafor as a real-time rescue strategy for patients poorly mobilizing autologous CD34(+) cells.

Plerixafor enhances CD34(+) cell mobilization, however, its optimal use is unknown. We hypothesized that plerixafor could "rescue" patients in the midst of mobilization when factors indicated a poor CD34(+) yield. Of 295 consecutive autologous peripheral blood mobilization attempts at our center, 39 (13%) used plerixafor as rescue strategy due to a CD34(+) cell concentration <10/μl (median 5.95/μl, n = 30), low CD34(+) cell yield from prior apheresis day (median 1.06 × 10(6) CD34(+) cells/kg, n = 7), or other (n = 2). Patients received a median of one plerixafor dose (range: 1-4). Thirty-four (87%) collected =2 × 10 (6) CD34(+) cells/kg and 26 (67%) collected =4 × 10 (6) CD34(+) cells/kg. Median collections for lymphoma (n = 24) and myeloma (n = 15) patients were 4.1 × 10(6) and 8.3 × 10(6) CD34/kg, respectively. A single dose of plerixafor was associated with an increase in the mean peripheral blood CD34(+) concentration of 17.2 cells/μl (P < 0.001) and mean increased CD34(+) cell yield following a single apheresis of 5.11 × 10(6) /kg (P < 0.03). A real-time rescue use of plerixafor is feasible and may allow targeted use of this agent. J. Clin. Apheresis, 2012. © 2012 Wiley Periodicals, Inc.