in relation to the total number of RCC tumor cells inoculated (the Dose Level 
of the vaccine). A wide range of daily doses will be received by the 
patients. Only at Dose Level 4 will the daily dose of GM-CSF approach amounts 
which have been shown to stimulate hematopoiesis in patients (Table 14). 
TABLE 14 MAXIMUM POTENTIAL DAILY SYSTEMIC EXPOSURE TO GM-CSF 
POST CELL INJECTION 
DOSE LEVEL 
TREATMENT 
MAXIMUM DAILY GM-CSF EXPOSURE 
CELL DOSE 
(CELL DOSE x 48ng/ 10 6 /DAY ) 
4 
1 X 10 9 
48,000 ng (48 meg) 
3 
4 x 10 8 
19,200 ng (19.2 meg) 
2 
4 x 10 7 
1,920 ng (1.92 meg) 
1 
4 x 10 6 
192 ng ( . 192 meg ) 
The maximum, daily, systemic exposure to GM-CSF protein (assuming 100% 
bio-availability) in this study per day at maximum dose (Dose Level 4) appears 
safe. It is significantly less than (about 11%) the published of GM-CSF MTD 
by patients given the cytokine, either IV or subcutaneously. The MTD (defined 
as the occurrence of reversible grade 3-4 toxicity in at least 2/3rd of 
patients was determined to be 10 mcg/kg/day subcutaneously or 700 meg 
daily . 59,60,61 As a reference point, 1-6 mcg/kg/day is an approved usual starting 
dose in oncology patients using IV rhu GM-CSF, or 70 to 420 meg per day. The 
systemic pharmacokinetics of GM-CSF secreted by B16 melanoma tumor vaccine are 
presented in Appendix 14. A. 1, Figure 1. Nevertheless, unforeseen and 
synergistic toxicities between irradiated tumor cells and high level paracrine 
GM-CSF in the subcutaneous space may exist. If so, the two arm study design 
should enhance the likelihood of their detection. 
3.6.f. Choice of Both Intradermal and Subcutaneous Vaccination 
Routes 
The decision to do both intradermal and subcutaneous injections 
comes from our inability to use our murine models to determine which route is 
preferable. Mice do not have an intradermal space large enough to accommodate 
large cell doses. This issue may require head to head comparison in later 
phase II clinical studies provided the safety of each route of administration 
is shown in this trial. 
There is evidence that the intradermal inoculation site could be 
superior in humans. In leprosy, for example, GM-CSF given intradermally has 
more efficacy in clearing infections than given subcutaneously. Intradermal 
vaccination appears superior to subcutaneous vaccination in immunization with 
Hepatitis B vaccine as well. 62,63,64,65 For these reasons, the intradermal route 
was not eliminated for clinical evaluation in this study in favor of the 
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