Work

Plerixafor Used in a “Just in Time” Fashion Allows Timely Autologous Hematopoietic Cell Transplant (HCT) in Patients Who Are at High Risk for Inadequate Apheresis

Year: 2016

Type: article

Abstract: One of the challenges for autologous HCT is the ability to collect an adequate number of progenitor cells in patients with limited hematopoietic reserve. We prospectively explored the ability of plerixafor, a CXCR4 inhibitor, when used in a “just in time” fashion to enhance progenitor cell collection in patients at high risk of collection failure. Between February 2013, to February 2015, we enrolled 73 patients with multiple myeloma (MM) (n=39) or non-Hodgkin's lymphoma (NHL) (n=34) who were to undergo first apheresis for autologous HCT. Patients were considered high risk for apheresis failure if they met at least one of the following criteria: age > 65, lines of chemotherapy > 2, cycles of chemotherapy > 12, prior exposure to irradiation, or any prior therapy with lenalidomide, or fludarabine. High risk patients had peripheral blood (PB) CD34+ cell counts measured one day prior to start of apheresis. Plerixafor was used in one of three situations: if the total number of CD34+ cells collected was < 25% of target (defined as ≥ 4 x 10ˆ6 CD34+ cells/kg/transplant) after 1 day of collection or <50% of target after 2 days of apheresis, or if patients had a PB CD34+ count < 20 cells/uL prior to first day of apheresis. Patients were followed for 6 months after transplantation. Results are summarized in the table below. The risk criteria were good predictors for the need for plerixafor. As expected, a greater number of patients who did not require plerixafor (plerixafor-) collected the target number of progenitor cells compared to patients who required plerixafor (plerixafor+). There were no significant differences in engraftment kinetics, however, there was a statistically significant increase in transfusion of both platelets and blood in the plerixafor+ group, possibly due to impaired marrow function. This trial shows thatplerixafor given in a “just in time” fashion can result in adequate mobilization and allow patients at high risk of mobilization failure to proceed towards autologous transplant.Tabled 1NAge (y)*Plerixaforgiven (%)*ApheresisDays toTxTransplant# Days Collect# Collect Target (%)# CollectAdeq but < Target (%)ANC >500Plt>50# PRBC#Plt*Apheresis RiskStandard4257.712 (28.6)2 (1-4)31 (73.8)40 (95.2)18 d13 d21 d24High3163.821 (67.7)2 (1-4)18 (58.1)30 (96.8)17 d13 d21 d27* P-value < 0.05NAge (y)High risk (%)*ApheresisDays toTxTransplant# DaysCollect# Collect Target (%)# CollectAdeq but < Target (%)ANC >500Plt>50# PRBC*#Plt*Plerixafor+3361.621 (63.6)2 (1-4)19 (57.6)30 (90.9)18 d13 d24 d37Plerixafor-4059.110 (25.0)2 (1-4)30 (75.0)40 (100.0)17d13 d20 d24* P-value < 0.05 Open table in a new tab * P-value < 0.05

Source: Transplantation and Cellular Therapy

DOI: 10.1016/j.bbmt.2015.11.454