HIV Vaccines - Accelerating the Development of Preventive HIV Vaccines for the World: Summary Report and Recommendations of an International Meeting

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Market considerations
Estimates of the size of the market for a preventive HIV vaccine are difficult to make as there are
many uncertainties, including the acceptability of the vaccine to the population; the perceived
risks of acquiring HIV; the amount people or institutions will pay for a vaccination course; the
willingness of different institutions to cover the costs of a vaccination course for those who cannot
afford to pay; and national government vaccine policies.
In the developed countries, in the absence of broad recommendations for vaccination the greatest
demand for a preventive vaccine will come from those individuals who regard themselves as at
high risk of infection. Estimates of the percentage of the population who regard themselves as at
high risk of infection are small. The experience with the use of hepatitis B vaccine in health care
providers and homosexuals also confirms the difficulty of expecting a broad voluntary uptake.
Among population groups identified as at high risk of infection, such as sexually active
homosexuals and intravenous drug users, it is likely that only a proportion of individuals will come
forward to be vaccinated even if the vaccine is free or highly subsidized. Individuals may not
identify themselves as at risk of infection, and in areas where intravenous drug use is illegal or
homosexuality is stigmatized, they may not be willing to step forward to be vaccinated. Even if all
homosexuals and intravenous drug users were vaccinated, the number of vaccination courses
required is not large. Assuming 2% of adult males are sexually active homosexuals, and 0.1% of
the adult population uses intravenous drugs, then less than 5 million full courses would be
required to vaccinate all members of these two groups in the developed world, and probably less
than 150,000 courses a year to vaccinate all individuals entering the two groups. Heterosexuals
with multiple sexual partners and certain cadres of medical professionals (e.g. surgeons) have
also been identified epidemiologically as being at high risk of infection. The prevailing view is
that only a very small proportion of heterosexuals consider themselves at risk of infection. It is
difficult to predict, however, how the general heterosexual population will respond to the
availability of a preventive HIV vaccine.
The developed countries account for only 15% of the worlds population and 7% of new births. In
other words, the potential demand for an HIV vaccine is substantially greater in the developing
world than in the developed world. The resources to purchase a preventive HIV vaccine,
however, lie disproportionately within the developed countries and will continue to do so for the
foreseeable future in the absence of international subsidies. In general, the countries with the
highest incidence of HIV and hence with the greatest need for a preventive vaccine are also
among the poorest. For example, the total per capita expenditure on health care in sub-Saharan
Africa (including both public and private funding but excluding South Africa) in 1990 was
US$ 13.5 and in India US$ 21, a fraction of the amount spent in Europe or North America.
Comparable figures for France and the United States were US$ 1,945 and US$ 2,763 respectively.
Public policy environment
The meeting did not focus on the public policy environment in detail. The general view, however,
was that the current public policy environment for vaccine development was not favorable.
Positive steps will have to be taken if pharmaceutical and biotechnology companies are to be
encouraged to commit more fully their expertise, experience and resources to the development of
a preventative HIV vaccine. This is especially true if industry is to be encouraged to invest in
vaccines that will meet the technical requirements of the developing world.