[Letter to Jack Chow from Anthony Fauci]

Page 2 - Dr. Jack Chow

and our need to understand its importance; and 4) the lack of strong
protective immunity evoked by the vaccines now in early clinical
investigation.
Regarding the second point, the selection of vaccine type, scientists agree
that insufficient information currently exists for us to make such a choice at
present. There are considerable advantages and disadvantages to various
vaccine types in terms of safety and the type of immune responses they may
evoke. In fact, it is now thought by scientists in the field, that a
combination approach of more than one vaccine type may be used to elicit a
broad-based immune response. It is further possible that different vaccines
may be needed for different populations. Much research remains to be done
before we can determine which of the several possible vaccine types would be
best either alone or in combination.
The National Institutes of Health has relied heavily on the advice of
scientific leaders in the field to make the critical and difficult decisions
regarding selecting vaccines candidates. It has used several standing
committees, including the.National Advisory Allergy and Infectious Diseases
Council, the NIAID AIDS Research Advisory Committee, and the NIH AIDS Program
Advisory Committee. In addition, it has called upon several ad hoc committees
of the top scientists who are working on HIV vaccines and who have important
expertise in related scientific areas. Thus, throughout the year, these
meetings have been taking place to provide a forum for leaders in the field to
discuss the future of HIV vaccine research.
We were recently asked whether selecting a vaccine would be premature at
present and whether such a selection would be detrimental to the development
of other products. There is a high degree of consensus, supported by the
issues outlined above, that it is premature to select a vaccine for large
efficacy trials from the products currently available because we do not have
sufficient information on their efficacy.
I hope you find this information helpful. If we can be of further assistance.
please do not hestitate to contact us.
Sincerely,
Anthony.Fauci, M.D.
Director
National Institute of Allergy and
Infectious Diseases
Enclosure