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Bangkok 2004

A glimpse of the future at the dawn of the “scale-up” effort

By Emily Bass

At times, the 15th International AIDS Conference in Bangkok (11-16 July 2004) crackled with the paradigm-shifting outrage and activism that enlivened the Durban meeting in 2000; at other moments it was steeped in the Barcelona 2002 gathering’s sober acknowledgement that, two decades into the epidemic, the response is too little, too late in far too many parts of the world. Ultimately, however, the Bangkok gathering—the first of its kind since substantial support for antiretroviral (ARV) programs began to come from the Global Fund to Fight AIDS Tuberculosis and Malaria, the US Presidential Emergency Fund for AIDS Relief, the World Bank and other sources—moved beyond these past meetings and provided a first glimpse of both the inspiring possibilities and the significant shortcomings of the nascent efforts now underway to “scale-up” ARV treatment in the world’s resource-poor countries.

Clinicians from resource-poor countries like Haiti, Zambia and Uganda reported that even small-scale ARV programs are having a dramatic impact on individual health, as well as HIV-related stigma and voluntary counseling and testing. As Haitian AIDS clinician Jean Pape showed slides of rudimentary clinics dispensing ARVs and program vehicles navigating flooded roads, it was possible to imagine that the ambitions expressed in Durban— treatment for all who need it—might someday be realized.

However these moments of uplift were outweighed by dire predictions from global leaders and activists alike that the existing targets for treatment will not be met without additional investments of human and financial resources and political will. Jim Kim, AIDS director at the World Health Organization, warned that the organization would not meet its “3 by 5” program goal of treating 3 million people in resource-poor countries by 2005 without increased funding and human resources. With just 13 months until the end of 2005, there are still only an estimated 440,000 people from resource-poor countries receiving ARVs. “By these measures of human life, the ones that really matter, we have failed. And we have failed miserably to do enough in the precious time that has passed since Barcelona,” said Kim. A UNAIDS report released at the conference predicted by 2005 a 50% shortfall of US$6 billion of resources required for prevention, care and treatment services if funding continues at existing levels.

There was also alarming news on the prevention front. Released at the conference, the most recent UNAIDS report estimates that there were a record 5 million new HIV infections in 2003. The report also emphasizes the increasingly devastating impact that the virus is having on women, who are disproportionately infected in virtually every corner of the world. Unfortunately the meeting will also be remembered for the instances when unanimity on the urgent need to improve existing prevention options was nearly sidelined by debates over the relative contributions to prevention outcomes of the various components of the “ABC” strategy—abstinence, being faithful and using condoms. Many researchers, including South African scientist Quarraisha Abdool Karim, sought to counteract the ideological tenor of these debates with hard evidence. In her plenary address, Abdool Karim reminded the audience that “promotion of male condoms is effective in both research and real world settings and it can play a critical role in prevention of heterosexual transmission in developing countries—this has been clearly demonstrated in both Thailand and Uganda.”

On a more positive note, there were no signs that prevention would be sidelined in the context of treatment scale-up. Instead, many speakers emphasized the complementarity of these two aspects of a comprehensive response to the epidemic. “Without a greatly expanded prevention effort, treatment is simply not sustainable,” said Peter Piot, Executive Director of UNAIDS, during the conference’s closing ceremony.

Recognizing the role of injection drug use in spreading the epidemic in Thailand and neighboring countries like Vietnam, Laos and Burma, many speakers called for expanded access to syringe exchange and drug replacement programs. Others described novel trials that will measure the effect of “structural” interventions such as income generation on vulnerability to HIV, asking, for example, whether HIV incidence is lower among women who have their own financial resources.

There was also considerable enthusiasm for novel approaches which will be tested in efficacy trials in the near future, including five candidate microbicides, pre-exposure chemoprophylaxis using tenofovir and herpes simplex virus type 2 prophylaxis. On the conference’s final day, prevention track rapporteur John Kaldor (National Centre in HIV Epidemiology and Clinical Research, Australia) commented that, while none of this research was news at Bangkok, there was still a mood of “relief” among people committed to prevention “even if we have the collective feeling of having to hold our breath for a couple of years until the results start coming through.” Microbicides, in particular, were hailed as a crucial area of research that might help reduce women’s vulnerability to infection.

On the vaccines front, there were updates on recruitment and retention strategies from the multiple trials that started in 2003 as well as studies looking at the willingness to participate in vaccine trials, vaccine demand and other issues in different populations. On the scientific front, there were reports on viral diversity and superinfection and updates on vaccine science and HIV immunology.

AIDS vaccines: A marathon amidst a sprint

While at times the conference highlighted the interdependence of prevention and treatment, at others it sharpened the distinction between immediate responses to the epidemic, such as treatment programs, and longer term research endeavors like the development of an effective AIDS vaccine or microbicide. The sprint to scale-up is happening at a time of scaled-back expectations for the AIDS vaccine effort and at Bangkok the immediacy of the scale-up goals at times made vaccine timelines seem all the more distant.

“The development of an HIV vaccine represents one of the most difficult challenges that modern biomedical science is confronting,” said Jose Esparza, Senior Advisor on HIV Vaccines at the Bill & Melinda Gates Foundation in his plenary speech on vaccines. His comments echoed the assessment of IAVI’s 2004 Scientific Blueprint for AIDS vaccine research that was released at the conference, which stated that “the progress of the past few years is outweighed by critical scientific, operational and resource challenges.” The Blueprint also noted that the field will not know whether the current vaccine strategies being tested will provide any benefit until “late 2007 at the earliest.”

The general sense that AIDS vaccines are a long-term prospect may have contributed to the relative silence on them outside of sessions specifically devoted to the topic. For the first time in several years AIDS vaccines were not mentioned by any speakers during the opening ceremony. Likewise, much of the news coverage of AIDS vaccines during and after the conference emphasized the extended timeframes for identifying an effective candidate.

“I was a bit concerned that the press clips [on AIDS vaccines] focused mainly on the difficulties and scientific challenges,” said Esparza. “Many people took that to be pessimistic. It is also realistic.”

“No major leadership event or speech should go without mentioning short- and long-term goals” for the global response to AIDS, said Seth Berkley, IAVI president and CEO. Berkley also voiced hopes that AIDS vaccine advocacy will be taken up by a wider range of groups, saying that “AIDS vaccine work needs to roll into the global AIDS community, because they are the ones who have to take the lead.”

Many vaccine advocates feel that distinguishing between realism and pessimism may be the field’s greatest challenge in coming years. “Realism will be a boon to the field if it takes the form of accurate estimates of the resources needed to finance the search for an AIDS vaccine, broad coordination among research groups, and widespread political support from governments and communities who have appropriate expectations of the pace of research and its likely short- and long-term outcomes,” says Mitchell Warren, Executive Director of the AIDS Vaccine Advocacy Coalition. Such an outlook would include a sense of the magnitude of the challenge but stops short of pessimism, which runs the risk of dissuading donors from further investment, research groups from further collaboration, and communities and governments from further participation in the effort, Warren says.

One way to help draw this distinction is to develop more detailed estimates of the funds needed for the AIDS vaccine research effort, says Rob Hecht, head of Public Policy at IAVI, who attended a pre-conference satellite where resource-tracking estimates for vaccines and microbicides were discussed. “We need to be very conservative in our predictions about how long it is going to take to find an AIDS vaccine and how much it is going to cost,” Hecht says, adding that another top priority is to develop improved estimates of the public health impact of an effective AIDS vaccine which “could be one of the most cost-effective interventions ever developed” even if the research process is as lengthy as scientists now predict it will be.

Just four years ago in Durban, AIDS vaccines were seen as a beacon of hope and treatments were deemed all but impossible; at a moment when the positions are reversed, treatment advocates are also emerging as important teammates in the AIDS vaccine marathon. And in the midst of the sprint to scale-up, treatment activists like South Africa’s Zackie Achmat emphasized that additional improved prevention strategies will be needed to complement services for those already infected. “It is important to find an AIDS vaccine and I think it is doable, although it will not be easy—just as it is not easy to do treatment. But it is important to do that too.”