Pre-IDE Submission: Clinical Protocol 
Neuroblastoma Bone Marrow Purging System 
BAXTER HEALTHCARE CORPORATION, HYLAND DIVISION 
Outcome iia) implies that the purging procedure did not adequately remove 
neuroblastoma progenitor cells. Although we will test for evidence that 
unpurged marrow contributes more relapse progenitor cells than purged 
marrow by analysis of clonogenic cells, the sample size will probably not 
allow detection of a significant difference. This outcome implies that gene 
marking could be used to address this question and the data will be useful in 
the design of further studies. 
Outcome iib) indicates that purging is effective and further improvements in 
the procedure would not be detectable using the current approach. The data 
would allow the design of studies to validate the efficacy of purging. For 
example, if only markers from the unpurged aliquot were detected in 14 
consecutive marked relapses, and assuming that (i) no markers from purged 
marrow were detected, and (ii) all technical procedures performed as 
anticipated, one could be 95 % confident that purging would be effective 80% 
of the time in a comparable patient population. The Phase 2 studies outlined 
here would allow a calculation of the number of patients that would have to 
be entered to detect 14 marked relapses. 
6.3 REGULATORY OBLIGATIONS OF THE INVESTIGATOR AND 
SPONSOR 
6.3.1 CLINICAL INVESTIGATORS AND INSTITUTIONS 
Baxter Biotech Group, Immunotherapy Division, will select the investigators) on the 
basis of their expertise in the field of oncology and in the care and treatment of patients 
with cancer. The appropriateness of the facility to conduct a research study of this 
nature, and the patient load of the institution with which the investigator is affiliated are 
also considerations. The investigator will: 
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Recombinant DNA Research, Volume 16 
