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Global Alliance for TB Drug Development*

Section 2 HIV/AIDS*

1. The problem: overview

Since the HIV/AIDS epidemic began, almost 58 million people throughout the world have been infected with HIV and almost 22 million people have died. HIV continues to spread, causing more than 15 000 new infections every day – 95% of them in low- and middle-income countries. Today AIDS is the leading cause of death in Africa, and the fourth worldwide. Recent figures indicate that the number of cases is increasing rapidly in Asia and in Eastern Europe.1 In some areas of Southern Africa, more than 30% of pregnant women are HIV-positive. Life expectancy in the region has dropped from 62 to 47 years, and some of the countries hardest hit could lose more than 20% of their GDP by 2020 as a result of AIDS.

Despite advances in treatment and care , which are now widely available in high-income countries, the availability of a n t i re t roviral drugs, HIV/AIDS pre v e n t i o n programmes and the infrastructure of health services to provide them are lagging behind in low- and middle-income countries.

While not intended to be a comprehensive list of networks, the following website addresses contain information on current re s e a rc h networks working on HIV/AIDS:

http://www.who.int/

http://www.who.int/HIV-vaccines/

http://www.unaids.org/

http://www.iavi.org/

http://www.ivi.org/

http://www.avac.org/

http://www.cdc.gov/hiv/vaccine http://www.microbicide.org/

2. Research issues

The following is a list of research issues recommended by partners working on HIV/AIDS research.

2.1. Research on AIDS prevention (a) Interrupting transmission2,3

Prevention programmes need to take into account the social context, including p e rceptions of rights to safer sex, the experience of violence, limited economic opportunities for women and the rise of sex work, communication skills, existing gender norms, the knowledge of and use of condoms and the interruption of mother- t o - c h i l d transmission. And these will have to be dealt with through sustained education, skills training and support for behaviour change.

While unsafe sex and injection drug use continue to fuel the broadening epidemic, it is at the same time shifting to the more

disadvantaged communities. It is imperative that these communities get the resources and support needed to take up the prevention message.

Twenty years into the epidemic, millions of young people still know little, if anything about the epidemic (see Section 7 on reproductive health in this chapter). In some countries, many have never even heard of AIDS, and of those who have, many have serious misconceptions about how HIV is transmitted. Data from the Hlabisa region in South Africa, for example, indicate that the incidence rate of HIV among prenatal clinic attendees aged 15-49 has risen from about 2%

in 1993 to almost 20% in 1999 and that the ages with the highest prevalence and incidence are between 20 and 29 years. Any successful AIDS response will re q u i re providing young people with the information and life skills they need in order to prevent infections.

Research recommendations

• Conduct operations re s e a rch and implement interventions with known efficacy.

• Identify and incorporate the social context in interventions geared to interru p t transmission.

• Conduct operational re s e a rch on implementation of programmes aimed at interrupting mother-to-child transmission of HIV.

• Document the shift of HIV transmission to the more disadvantaged communities and identify ways to address this shift.

• Identify strategies to ensure that disadvantaged communities get the resources and support needed to take up prevention messages.

• Identify strategies to ensure that young people have the information and life skills they need in order to prevent infections.

(b) Vaccines (International AIDS Vaccine Initiative)

Although the scientific and technical challenges in the development of AIDS vaccines are formidable, pro g ress so far suggests that these hurdles can and will be overcome. To date, more than 30 candidate vaccines have been tested in over 60 Phase I/II trials, involving approximately 10 000 healthy volunteers, mainly in high-income countries.4 To accelerate the development of an HIV vaccine, additional candidate vaccines must be evaluated in parallel in both high- and low-to middle-income countries.

However, the development of a safe and effective AIDS vaccine is not an end in itself.

To succeed in developing an AIDS vaccine and fail to make it accessible to those most in need would be a major defeat for mankind.5 Research recommendations

• Accelerate the development of an HIV vaccine by evaluating additional candidate vaccines in parallel in both high- and low-to middle-income countries.

• E n s u re that future products will be available, acceptable and aff o rdable in resource-poor settings.

(c) Microbicides

The development of an HIV/AIDS prevention method that women can control could save millions of lives. The use of an effective vaginal microbicide could offer women the protection needed, and research has shown that women want such a product. The goal of

4 Jose Esparza, Coordinator, WHO/UNAIDS HIV Vaccine Initiative. WHO Bulletin(2001) 79 (12):1133-1137.

5 Yvette Madrid, consultant. Paper presented at Forum 5, October 2001.

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the International Microbicide Initiative, as p a rt of the overall eff o rt to combat the epidemic, is to mobilize the international community to develop and make available microbicides as rapidly as possible.6

Over 60 compounds are currently under consideration, and Phase III clinical trials are needed to evaluate their eff e c t i v e n e s s . However, these trials will require substantial human and financial resources as well as political will and consideration of ethical issues. Up till now, the pharm a c e u t i c a l industry has not invested in this field. It has been suggested that it might be possible to set up simultaneous vaccine and micro b i c i d e trials. However, it is critical to ensure that future products will be available, acceptable and affordable in resource-poor settings.

Research recommendations

• Mobilize the international community to develop and make available microbicides as rapidly as possible.

• E n s u re that future products will be available, acceptable and aff o rdable in resource-poor settings.

• Link HIV vaccine trials with field trials of microbicides.

2.2. Research on AIDS treatment (a) Access to drugs

While the availability of antire t roviral drugs in mainly high-income countries over the past two years has increased life expectancy and the quality of life among people infected with HIV/AIDS, most low- and middle-income countries lack access both to lifesaving dru g s of health workers as important factors. It also d rew attention to the lack of large-scale donor s u p p o rt to buy medicines and to the need to reduce prices. In Febru a ry 2001, Oxfam launched the Cut the Cost campaign,8 focusing on the adverse impact of patents on poor people/countries from a public health and basic human rights perspective, and on the inadequate access of the poor to essential d rugs. The campaign made re c o m m e n d a t i o n s and suggestions to WTO, WHO, transnational companies, national governments and the i n t e rnational community to increase access to a n t i re t roviral dru g s .

Research recommendations

• Investigate the barriers to antire t ro v i r a l drug access in low- and middle-income countries.

• Evaluate the role of (i) poor health infrastructure and (ii) treatment pricing in access to antiretroviral treatment.

• Review the role of international institutions in helping to increase access to a n t i re t roviral treatment in low- and middle-income countries.

• Conduct cost-effectiveness analysis to determine the best strategy to initiate large-scale treatment programmes in resource-limited settings.

• Replicate the success achieved in Brazil in curbing the HIV epidemic, and measure the impact in other low- and middle-income countries.

6 George Brown, Health Equity Program, Rockefeller Foundation. Paper presented at Forum 5, October 2001.

7 World Health Organization, Macroeconomics and Health: Investing in Health for Economic Development, Report of the Commission on Macroeconomics and Health, December 2001.

8 Ruzanna Stepayan, Oxfam GB, Armenia. Paper prepared for Forum 5, October 2001.

9 Mauro Schechter, Universidade Federale do Rio de Janeiro, Brazil. Paper presented at Forum 5, October 2001.

10 Christina Mwachari, Kenya Medical Research Institute, Kenya. Paper presented at Forum 5, October 2001.

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