Human Gene Therapy Subcommittee - 7/30/90 
occurring in 15-30 minutes after administration. He said these 
effects were probably due to effects of TNF locally which affect 
the vasculature and injure recirculation, possibly due to local 
formation of oxygen-free radicals, resulting in tumor reduction. 
Dr. Rosenberg said that despite these successful animal 
experiments, TNF administration in humans had been an abysmal 
failure. Injection of TNF into 39 patients by both continuous 
and bolus infusion at maximum tolerated levels failed to produce 
antitumor effects. It is thought that the reason for this is a 
difference in the ability to achieve local concentrations of TNF 
in the mouse and the human. He noted that it was possible to 
inject inbred mice bred to endure endotoxin-mediated infections 
at a level of 400 mg/kg. Therefore, they tolerate TNF much 
better than humans, in whom the maximum tolerated dose by i.v. or 
bolus infusion is 8-10 mg/kg per day. However, if a high enough 
concentration of TNF capable of mediating tumor reduction could 
be achieved at the tumor site without systemic toxicity, the same 
antitumor benefits might be achieved. This is the rationale for 
this proposed protocol. 
Dr. Rosenberg presented a series of slides. He began with slides 
of the ongoing N2/TIL protocol showing that 5 patients had TIL 
cells bearing the marker gene after 21 days, which is the time at 
which IL-2 supplementation is discontinued. Further, the cells 
were found in tumor biopsies of the patients. He noted that all 
safety studies required by the subcommittee had been performed 
and were negative without exception. Further, safety studies of 
the viral supernatant that transits to TILs (tests of patient 
exposure to virus) have also been negative. He said that these 
same tests would be performed in the TIL,j,jjp protocol. 
Dr. Rosenberg said the current attempt to introduce the TNF gene 
is based on the observation that TIL recirculate and localize to 
cancer deposits, both from scans with indium^^^ and from actual 
measured accumulation of radioactivity in tissue. He also 
presented data showing that human tumors in nude mice are made to 
regress due to introduction of transduced cells using the same 
vectors that are expected to be used in the protocol. Further, 
he presented data from three studies that showed that local 
injection of TNF into human tumors results in tumor regression. 
Dr. Rosenberg noted that an addendum to the protocol contains 
results of experiments by Dr. Attan Kasid which show that the 
viral vector has stable expression of the TNF gene and that TILs 
can be produced which will make 100 times the normal amount of 
TNF. 
[80] 
Recombinant DNA Research, Volume 14 
