Bertrand Audoin, the new head of the society says during hard times financially, the only option to keep ahead of the HIV epidemic is to find a cure.
Speaking days before the 30th anniversary of the first medical reports of the disease on Sunday, he admitted finding a cure might take as long as 25 years.
Nearly 30 million people have been killed by acquired immune deficiency syndrome (AIDS) and more than 33 million others have the HIV virus that causes it. Some experts warn that talking about a cure could spark false hopes, and it would be better to develop a vaccine.
"It is the right moment - from the scientific and financial point of view - to invest more time and money in researching a cure,” said Mr Audoin.
"There is already some basic science in this area,” he told the BBC. “We know that some people who are on HIV treatment can contain the virus in a way which makes them unable to infect other people.
"So we think further work could help us develop a functional cure, which would allow the virus to remain latent in the body, without people feeling sick or needing treatment. That's the goal."
The world has made massive progress against the disease since it first became widely known about in the early 1980s. First a test was developed, then anti retrovirals drugs which keep HIV to below detectable levels, but anti retrovirals are not a cure and can have nasty side-effects.
Mr Audoin, who now runs The International AIDS Society, the world’s leading independent association of HIV professionals, stressed that for all the lives that are saved, the more money that is needed for patients to take the drugs they need every day for the rest of their lives.
"At the moment, for every one person beginning treatment in badly affected countries in Africa, two people get infected with HIV in that time.
"So treatment with anti-retroviral drugs isn't the only solution in the long run.
“The hardest part will be convincing donor governments and other funding organisations to put money into research.
"But if we don't invest in the science, the epidemic will go faster than our work on it - and the financial situation will make it more difficult to put people on treatment."