Launching its annual report in Paris, The Global Fund said countries where it invests had seen 17.5 million people receive antiretroviral treatment against HIV and five million people tested and treated for tuberculosis.
But it warned that a historic opportunity to eradicate killer diseases including malaria was at risk of being missed.
“We have in our sights, but not yet firmly in our grasp, the prospect of freeing communities from the burden of HIV, TB and malaria,” said the fund’s executive director, Peter Sands.
“Together, we can end these epidemics, but achieving this goal will require change — increased investment, accelerated innovation, even more effective partnerships and a relentless focus on impact.”
Having declined strongly since the peak of the global crisis that has killed at least 35.4 million people since the early 1980s, HIV rates in recent years have dropped more slowly.
The UN says 1.8 million people were newly infected last year with HIV, and there were 940,000 AIDS-related deaths.
“Global HIV infection rates are now declining frustratingly slowly, and are actually rising in some regions and among some populations,” Mr Sands wrote in the report.
The fund said HIV infections remained troublingly high among adolescent girls and young women. In some African countries, young women aged 15-24 are up to eight times more likely to be HIV positive than young men, it said.
The Global Fund, which says it has saved 27 million lives since its creation in 2002, suggested the goal of reducing new infections to 500,000 by 2020 was likely to be missed.
Last year, the World Health Organization sounded the alarm when it said tuberculosis had surpassed HIV/AIDS as the world’s number one infectious killer and was the ninth cause of death worldwide.
About 1.7 million people died from TB in 2016 out of 10.4 million worldwide who became ill from the severe lung infection, according to the WHO.
Wednesday’s report also warned that cases of malaria were on the rise, with five million more infections registered in 2016 compared with a year earlier.
The Global Fund groups together states, NGOs and private sector firms in investing nearly $4 billion (3.4 billion euros) each year to support public health programmes around the world.
Its main contributors are the US, Britain, France, Germany and Japan.
Donors pledged $12.9 billion to the fund for the current period, which ends next year.
Reacting to Wednesday’s report, a collection of aid agencies said that billions more than that would be needed between 2020-2022 to maintain the fund’s work.
“The direct and indirect costs of these epidemics are and will be much higher than the estimated costs of putting an end to them,” the group said in a statement.