[Final Program, International Conference on AIDS (4th: 1988: Stockholm, Sweden), Book 2]

6573

DEVELOPMENT OF VACCINIA-BASED VACCINES FOR SIV

Linda Gritz,* G. Stallard,* S. McKenzie,* A. Destree,*
D. Panicali,* Y. Naidu,** H. Kestler,** R. Derosiers,**
*Applied bioTechnology, Cambridge, MA and **New England
Regional Primate Research Center, Southborough, MA, USA.
Objective: To evaluate prototype recombinant vacciniabased vaccines for the prevention of AIDS in a nonhuman primate model system based on simian
immunodeficiency virus (SIV).
Methods and Results: The development of an AIDS-like
syndrome in macaques following infection with SIV allows
the evaluation of potential vaccines in a primate model.
Prototype vaccines were composed of recombinant vaccinia
viruses that contain one or more SIV genes from an
infectious SIV proviral clone. Expression of SIV
antigens by these recombinants was assayed by several
methods, including black plaque assay (an in situ enzyme
immuno-assay performed on viral plaques),
radioimmunoprecipitation and Western blot analysis. For
preliminary immunological analysis, mice were immunized
with the recombinant viruses and serum samples were
tested both for specific responses to SIV antigens and
for SIV neutralizing activity. Evaluation of the immune
responses induced and the protection afforded by these
vaccines in macaques is in progress.

6574 HUMAN IMMUNODEFICIENCY VIRUS VACCINE:
RECRUITMENT OF HEALTHY VOLUNTEERS
Debra Ogata-Arakaki*, Victoria Davey**, Dianne Lee**,
Margaret Megill** CC*, NIAID**, NIH, Bethesda,Maryland,USA.
Objective. The first USA licensed trial testing the safety and immunologic
effects of a vaccine against human immunodeficiency virus (HIV) has
required the recruitment of motivated individuals fitting a predetermined
profile. We have assessed the resources necessary to recruit, screen, and
immunize 81 volunteers for this trial.
Methods. Self-referred individuals meeting basic entry criteria, which
included HIV seronegativity by outside laboratory, were evaluated by four
AIDS research nurses in telephone interviews using protocol-specific
checklists. In a two-tiered screening process, candidates interested and
eligible after phone interview were assessed at the NIH by history, physical,
and laboratory examination. Upon completion of the screening process, those
eligible were enrolled and vaccinated.
Results. To date, there have been 448 telephone inquiries, each requiring an
average of 40 minutes of researcher time. After telephone interview, 81%
were found to be eligible and offered further screening. Primary reasons for
disqualification at the telephone screening were voluntary withdrawal (10%--
reasons cited included concern about potential side effects, time involved in
participation, and lack of remuneration), high-risk sexual practice (5%),
seropositivity (2%), concurrent medical illness (2%). Of those accepting onsite NIH screening 9% did not keep scheduled appointments, and 8% were
found ineligible on the basis of physical or laboratory exam. Preliminary
results indicate that after completing evaluation, 82% (32) of those eligible
were vaccinated.
Conclusion. Including all phases of screening, accrual of 32 candidates (40%
of sample size) required approximately 600 manhours. Telephone
interviewing, while time-consuming, may be an efficient means of recruiting
suitable candidates for HIV vaccine. In this study 19% of ineligible or
uninterested volunteers were eliminated on initial phone call. The rate of
vaccination after on-site visit is 82%, which would have been lower without
the time invested in careful telephone screening. These findings should
assist other programs in determining the resources needed to develop a
vaccine program.

Notes:

6575

Motivations of Persons Volunteering for an
AIDS Vaccine Trial

B. BARRICK, C. BERKEBILE, S. CUDA, L. GOVONI, C. GRADY,
B. HAHN, Y. ROSENTHAL, N. SEARS, M. MEGILL,
National Institute of Allergy and Infectious Diseases,
Bethesda, MD.
This study will identify and categorize the reported
motivations of persons who volunteer for and receive the
first United States trial of a recombinant vaccine
against the Acquired Immunodeficiency Syndrome (AIDS)
virus (HIV). The study will be an exploratory study
using printed survey and demographic instruments.
Subjects will write and rank responses to the question
"Why did you volunteer for this study?" The
investigators will use content analysis techniques to
assess responses for themes. This study will add to
the knowledge of reasons persons volunteer for studies
with potentially risky or ambiguous outcomes and
therefore enhance the process of providing informed
consent, providing medical and nursing care, and
planning methods of recruitment.

6576 IMMUNIZATION OF CHIMPANZEES AGAINST
HIV USING WHOLE INACTIVATED VIRIONS
Marc Girard*, F. Barre-Sinoussi*, F. Reyxx,
M. Yagello+, M.P. Kienyx, J.C. Chermannxx,
E. Muchmore++, P. Fultz**, J.-P. Lecocqx,
J.-C. Gluckman+ and L. Montagnier*
*Pasteur Vaccins and Institut Pasteur, Paris, +UER PitieSalpetriere, Paris, XTransgene, Strasbourg, ++LEMSIP,
New York, **Yerkes, Atlanta and XXINSERM, Marseille.
Objective. Test the safety, immunogenicity and efficacy
of anti-HIV vaccines in chimps.
Methods. Partially purified HIV (LAV-1, BRU) was inactivated with formalin and betapropiolactone and made into
a prototype vaccine by mixing with a threonyl-muramyldipeptide base adjuvant (Syntex adjuvant formulation).
Two chimpanzees that had been previously immunized with
vaccinia virus recombinants expressing the HIV gp160 and
p25 antigens as well as one naive animal were injected
three times at monthly intervals by the I.M. route.
Results. Anti-HIV antibody titers as determined by ELISA
ranged from 12,800 to 51,200 after the 3rd injection.
Anti-gp160, anti-p25 and anti-p18 antibody titers well in
excess of 10,000 were also detected by Western blot
analysis. No antibody to the pol, F or Q antigens were
detected on appropriate blots, showing the absence of
virus replication in the animals. All cultures of PBL from
the animals were negative. The two preimmunized chimps
scored positive in T cell antigenic proliferation tests to
whole HIV or to partially purified HIV gp160.
Conclusion. Significant anti-env and anti-gag antibody
levels could be obtained in chimps by injection of inactivated HIV. The protective effect remains to be determined. There may be an advantage to preimmunization with
a live recombinant vaccine.

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