WASHINGTON, May 18 (IPS) - An influential group of AIDS activists is challenging the US administration to take the lead in the push for an HIV vaccine.

"The Bush administration must take ownership of the HIV vaccine challenge and provide global public leadership toward developing and delivering an HIV vaccine," says the US-based AIDS Vaccine Advocacy Coalition in an assessment of the state of vaccine research released Friday.

Titled 'Six Years and Counting: Can a Shifting Landscape Accelerate an AIDS Vaccine?' the report also calls on the US Congress to speed up passage of legislation to boost research incentives.

HIV has infected more than 50 million people to date and AIDS has killed more than 17 million, surpassing tuberculosis and malaria as the leading infectious cause of death in the developing world, researchers say.

President George W. Bush has not announced his position on tax incentives to develop vaccines against HIV, nor has he committed his administration to the 2007 deadline set by former President Bill Clinton.

In May 1997, Clinton conceded to pressure from the coalition and other groups by making the development of an HIV vaccine a national priority and setting 2007 as the deadline for achieving this goal.

Last week, the United States became the first country to commit to a proposed global fund to fight HIV/AIDS by pledging 200 million dollars. To mount an effective challenge to HIV and other infections, the United Nations estimates that the fund will require between seven billion and 10 billion dollars annually.

Overshadowed by the need for treatment and care of those already infected with HIV, the search for a vaccine has been slow, cautious and, critics say, often caught up in bureaucratic red tape.

"What we need is a new level of political and scientific leadership and it's important that the US lead the way in the establishment of a global fund" specifically to finance vaccine research, says Rose McCullough, the coalition's executive director.

Last year, Congress almost took action on the proposed 'Vaccines for the New Millennium Act', which would have covered HIV, tuberculosis and malaria vaccines, but the legislation was lost to year-end political gridlock.

It has been re-introduced this year and, if enacted, would provide tax credits for research and development, clinical trials, and delivery of priority vaccines. It would specifically encourage researchers to engage in neglected areas such as malaria and HIV and promote delivery to low-income countries.

Despite activists' sense of urgency, only one vaccine - AIDSVAX, currently being tested by the US-based company VaxGen - is expected to reach the final stages of clinical trials by 2003.

Susan Buchbinder, research director at the University of California-San Francisco Department of Public Health, says that if AIDSVAX proves effective in at least 30 percent of test cases, it may be approved for use in some countries.

However, distribution may be held up by technicalities such as building manufacturing plants - which can take up to five years to complete.

"We have stated publicly for some time that we will not be able to meet worldwide demand from day one," says Lance Ignon of VaxGen. "This is not going to be like the introduction of any other medical product."

McCullough says it is vital to have more than one drug in advanced development to raise the chances of success.

AIDSVAX trials are being conducted primarily on HIV subtypes most prevalent in North and South American, Europe, the Caribbean, Australia, Southeast Asia, and the western Pacific Rim.

No trials on the disease subtype that affects sub-Saharan Africa, India, and China have reached the advanced stages of development - even though this subtype is responsible for more than 70 percent of the estimated 36 million current HIV infections worldwide.

Several Western countries have scaled back or abandoned their HIV vaccine programmes. These include Britain, Canada and the Netherlands, leaving the French and US governments as the leading public-sector developers of a vaccine. The US government has yet to endorse tiered pricing, which analysts say will be vital if drugs are to be affordable for poor countries.

"There is talk, but little concrete action, on the principal issues that will determine the accessibility of HIV vaccines," says the coalition report. Steve Wakefield, of the government-financed HIV Vaccine Trials Network, says it takes between 10 and 20 years for new drugs developed in the West to reach people in poor countries.

Wakefield points to the Hepatitis B vaccine, which was licensed in the early 1980s, and the Haemophilus influenza b (Hib) vaccine, licensed in the late 1980s, as examples. They are still unavailable in many poor countries, "at the cost of hundreds of thousands of lives", he says. "We cannot afford to allow that to happen in the area of HIV/AIDS." (END/IPS/WD/NA/HE/gm/aa/01)