Highly purified CD34(+) cells isolated using magnetically activated cell selection provide rapid engraftment following high-dose chemotherapy in breast cancer patients

The primary objective of this study was to evaluate the safety of infusion of CD34(+) cells, selected using a clinical scale magnetically activated ce ll sorting device, assessed by time to hematological engraftment and incide nce of adverse events, Secondary objectives included evaluation of device p erformance in terms of purity and recovery of the CD34(+) cell product. Bre ast cancer patients suitable for transplantation received cyclophosphamide and filgrastim for mobilisation, followed by three leukaphereses, The produ cts of the first two leukaphereses underwent CD34(+) cell selection, The pr oduct of the third leukapheresis was cryopreserved unmanipulated. Following high-dose cyclophosphamide, thiotepa and carboplatin, selected CD34(+) cel ls were infused. In 54 patients who received selected cells only, the media n time to platelet recovery and neutrophil recovery was 11 days (range 5-51 ) and 9 days (range 5-51), respectively. There were no adverse events assoc iated with infusion of selected cells. A total of 126 leukapheresis samples was available before and,after selection for central CD34(+) analysis. The median purity was 96.1% (27.4-99.4) and the median recovery was 52.3% (15. 2-146.3). These data show that cells selected using magnetically activated cell selection provide safe and rapid engraftment after high-dose therapy.