cell s. 
c. What treated cells (or vector/DNA combination) will be given to 
patients In the attempt to administer gene therapy? How will 
the treated cells be administered? What volume of cells will 
be used? Will there be single or multiple treatments? If so, 
over what period of time? 
The bone marrow cells obtained from the patient will be exposed to the 
retroviral vector in vitro (see Section I.B.3.a). The treated cells after 
conventional washing will be administered to the patient by conventional bone 
marrow transplantation methods (i.e., intravenously). The total volume the 
patient would receive would not exceed 5 ml/kg. All the treated cells would be 
administered at one time at an infusion rate of approximately 1 ml/minute. The 
patient may be premedicated prior to the Infusion to reduce the possibility of 
any reaction to the treated marrow cells and other products. This pretreatment, 
which may Include the use of acetaminophen, steroid, demerol , and/or anti- 
histamines, Is often used In conventional and hapl o-matched bone marrow 
transplantation to minimize patient discomfort. 
d. What are the clinical endpoints of the study? Are there 
objective and quantitative measurements to assess the natural 
history of the disease? Will such measurements be used in 
following your patients? How will patients be monitored to 
assess specific effects of the treatment on the disease? What 
Is the sensitivity of the analyses? How frequently will 
follow-up studies be done? How long will patient follow-up 
continue? 
Since the patient is being treated for immune deficiency, the desired 
endpoint is full Immunological reconstitution. In vitro and in vivo studies 
will be used to follow the patient's immune functions, much as has been used to 
follow response to bone marrow transplantation of other children with SCID. 
Special tests designed to follow the retroviral -mediated gene transfer and 
possible effects of the retroviral vector would be utilized. The tests that 
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