[sci.med.aids] GP160 - AIDS vaccine update

@aides.watson.ibm.com@squid.cs.ucla.edu, , (09/19/90)

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The following is one abstract presented to the VI AIDS conference
in  San  Francisco, CA during June 1990 by MicroGeneSys,  Inc  of
West Haven, CT.  The results described here are very encouraging.

           Phase I Trial Evaluating Recombinant GP160
                   as a Candidate AIDS Vaccine

OBJECTIVE:    To  evaluate  the  safety  and  immunogenicity   of
recombinant gp160 in a dose-escalation study.

METHODS:   Recombinant gp160, produced in a  baculovirus  vector,
was administered to groups of 15 men at the following doses:  10,
20,  40, 80, 160, 320, 640 and 1280 ug.  Ten volunteers  in  each
group received a booster at 1-month, and for the groups receiving
160  ug and higher, 6 in each group received a second booster  at
6-months.   Safety monitoring including CBC,  blood  chemistries,
and  immune function, including CD4 counts.   Immunogenicity  was
evaluated  by recombinant (r) and licensed (l) ELISA and  Western
blot (WB) assays as well as blastogenic responses to  recombinant
gp160.

RESULTS:  No significant toxicity attributable to the vaccine was
seen.   Following  the 1-month booster, antibody  responses  were
detected in the 640 (5/10) and 1280 ug (7/10) groups by WB and r-
ELISA  but not l-ELISA.  Most volunteers developed  a  detectable
antibody response following the 6-month booster: 20/21 in the 160
to 1280 ug groups had antibody responses detected by WB and  7/21
by  l-ELISA.  Strong bands to gp160, gp120 and gp41 were seen  by
WB  and  responses have persisted for at least 6-months  in  most
volunteers.   R-ELISA  titers up to 1:25,000  have  developed  to
date.  Blastogenic responses to recombinant gp160 were seen at 80
ug or higher.

CONCLUSIONS:  Recombinant gp160 is safe at doses that can achieve
both antibody and blastogenic responses to HIV.  Further  evalua-
tions  of sera, including determination of neutralizing  activity
and antibody-dependent cellular cytotoxicity, are being performed
to  determine  the role of vaccine-induced  immune  responses  in
protecting against HIV infection.

--
Dan Greening		12 Foster Court			NY (914) 784-7861
dgreen@cs.ucla.edu	Croton-on-Hudson, NY 10520	CA (213) 825-2266