BOTHELL, Washington--CellPro, Incorporated has received FDA approval
for label expansion of the companys Ceprate SC Stem Cell
Concentration System to include the processing of peripheral blood
progenitor cells (PBPCs) to obtain a CD34+ cell enriched population
for use as hematopoietic support after myeloablative chemotherapy in
patients with CD34-negative tumors.
Studies have shown that these cells contain a reduced number of tumor
cells in the autograft, compared with unse-lected PBPCs, but have not
determined whether use of selected PBPCs will result in an improved
progression-free or overall survival. Ceprate was originally approved
in 1996 to select progenitor cells from bone marrow for
transplantation after myeloablative chemotherapy.
The FDAs decision was based on data presented to the Biological
Response Modifiers Committee by CellPro (see ONI, May, 1998). The
data came from a multicenter, randomized phase III clinical trial
involving 134 multiple myeloma patients receiving high-dose
chemotherapy followed by stem cell transplantation. The results
showed a median 1,000-fold reduction of tumor cells with cell
selection and purging, with equivalent neutrophil engraftment.
CellPros president and CEO, Richard Murdock, said that the
company "is especially pleased that the expanded label is very
broad in its applicability . . . and is not limited to purging
multiple myeloma tumor cells." The Ceprate system has been shown
in other studies to reduce the number of tumor cells in PBPC
autographs of patients with breast cancer and non-Hodgkins lymphoma.
The Ceprate system concentrates CD34+ cells using a proprietary
continuous-flow immunoadsorption technique. After cell harvest and
preparation, the cells are incubated with biotinylated murine
anti-CD34 monoclonal antibodies that bind selectively to CD34+ cells.
As they flow through a column, the antibody-labeled CD34+ cells bind
to avidin-coated beads while unlabeled cells are washed out.