Prior to the October 3 meeting, three other NIH committees had 
given provisional approval to the Anderson proposal. Institutional 
Review Boards of both the National Cancer Institute and the 
National Heart, Lung, and Blood Institute; and the NIH 
Institutional Biosafety Committee (IBC), asked for certain 
revisions to the protocol and gave their approval pending approval 
of the RAC. Dr. Walters asked Dr. Dinah Singer, chairman of the 
NIH IBC, to present a summary of the IBC deliberations. 
Dr. Singer 
On July 13, Drs. Anderson, Blaese, and Rosenberg appeared before 
the IBC to describe the TIL protocol. The IBC discussion centered 
on three points: 
1. Safety - What is the possibility of generating and 
detecting replication competent retrovirus? 
2. Dose - What is the optimal proportion of unmarked: 
marked TIL cells, considering the need to have sufficient 
marked cells to track without diluting the therapeutic 
dose of TIL? 
3. Animal Model - What information might be gained from 
additional efforts to develop an animal model, and is 
there reason to extend these efforts before initiating 
human trials? 
The IBC gave unanimous approval to the proposal with two 
conditions : 
1. The RAC must also give consent, and 
2. Additional animal data must be obtained. 
Following the October 3 RAC approval, the IBC met again on November 
4 and reviewed the following new data provided by the 
investigators : 
1. Transduction had not been found to alter TIL phenotype, 
cell surface markers, or IL-2 dependence; 
2. Assays were able to detect very low levels of replication 
competent virus against a large background of impaired 
virus particles (1 virus particle in 10 e ) ; 
3. Using polymerase chain reaction (PCR), marked TIL cells 
were detected in lymphocytes retrieved from a mouse. 
Recombinant DNA Research, Volume 13 
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