Finding an AIDS vaccine 'a marathon, not a sprint'

Hera Diani, The Jakarta Post, New York

In the history of infection, the only way to control a viral epidemic has been through the creation of a vaccine.

The same thing is true for HIV/AIDS -- a vaccine is seen as the best long-term solution to end the epidemic. This is particularly true because the current treatment systems, although they have advanced over the years, still remain unable to cure the disease and are financially unsustainable.

Yet, 24 years after the first HIV diagnosis -- the worst viral epidemic since the 14th century -- there has been only one vaccine type that has been fully tested to see if it works.

HIV/AIDS, meanwhile, continues to infect five million people a year, or 14,000 people daily, and the virus claims around three million lives annually.

Top AIDS scientist Seth Berkley, of the International AIDS Vaccine Initiative, said researchers faced huge challenges in creating a AIDS vaccine -- scientific ones mainly, but also economic and political obstacles.

Scientifically, Berkley said, the virus' genetic variabilities made it extraordinary difficult to deal with its separate strains.

"We know that on average people get infected, they have the virus circulated in their blood, and then that virus is held down until about a decade later until they get sick. So, we know that most people can control the virus, and the challenge is how to make that type of control more robust," he said at a workshop recently in New York.

With other vaccines, such as measles or polio, the alive, attenuated vaccine is given to people to give them a mild infection that does not make them sick but instead protects them.

"Nobody wanted to give weakened HIV to people. But we gave weakened HIV to monkeys and they actually were protected. Why does it work, what's the mechanism, and can we get the mechanism by some other means? The answer today is we don't know," Berkley said.

According to Berkley, there are more than 30 candidate vaccines in the pipeline and there is a lot of important science going on across the world. Vaccine trials are not only being conducted with animals but also with a small number of healthy human volunteers.

"If there are no side-effects, we'll move to a larger number of volunteers, including some people at high risk. But we will have to wait two to three years to see the reaction," he said.

Aside from the scientific challenges, there was also the market's failure to produce a vaccine, Berkley said.

While vaccines have extremely high social value, they have low economic value, which results in few parties being interested in investing in them.

"If you think of the economic value of creating new drugs, pharmaceuticals have a huge market and (drug companies) make a lot of money on AIDS as people have to take the drug every day of their lives.

"But with vaccine, you only give it once or a few times. And you can't charge a huge amount of money because otherwise people won't take it. We know that for HIV, the largest place that needs vaccines is in developing countries. So it ends up in a very small market," Berkley said.

AIDS is still a controversial disease and questions are frequently raised about should be vaccinated. There are ethical issues associated with vaccinating teenagers and adolescents let alone some elements of the high-risk population, sex workers and injecting drugs users.

"With all the combinations, the company says, 'I'd better stay away from this'," Berkley said.

Vaccines like the one for hepatitis B, used to be expensive but with increased production and better science they have dropped more than 100-fold in price. However, the hepatitis B vaccine has only been offered in developing countries during the past 11 years/it took 11 years to give the vaccine to developing countries.

Similarly AIDS drugs used to be very expensive but are now tracking down in price. However, they are still out of reach of some of the people who need them most.

Global access to these drugs had to be assured, Berkley said. Production must be dramatically stepped up, and systems needed to be created to reach sex workers and drug users, along with a regulatory framework that spans nearly 200 countries.

"Can you get developed countries to accept the fact that we would make the vaccine available at (an affordable) price in developing world? Say, it is OK to charge US$50 in the U.S., but 50 cents in developing world?"

Berkley said political support and leadership was needed to develop a vaccine, in what needed to be a global effort.

"The vaccine would be a small component in global health spending, only less than 1 percent, and in developing countries even smaller.

"We need to build a comprehensive agenda all the way, on all levels, with all the support. It takes long time financing. It's a marathon, not a sprint."