IN 2015, the Joint United Nations Programme on HIV/AIDS (UNAIDS) launched an ambitious target: to end the AIDS epidemic by 2030. The aim is that no child will be born with HIV and anybody already infected will be treated with medicines that give the best opportunity for healthy living.
This goal is in stark contrast to the early days of the epidemic, when the virus wreaked havoc. In the 1980s and 90s, an HIV infection was almost always fatal. But treatment has come a long way since then.
Today, nearly 21 million people around the world receive life-saving antiretroviral therapies, which can reduce the amount of the virus in the blood to undetectable levels. And scientists have even greater ambitions: some are developing vaccines, others are formulating long-acting treatments and still more are working on a cure. “HIV has changed from a deadly disease to a manageable disease,” says Jens Lundgren at the University of Copenhagen in Denmark, who has been working on HIV care and research for the past 30 years.
Until recently, HIV’s spread was rapid because it is easily transmitted via contact with infected blood and other body fluids. The most common routes of infection are through sex and shared needles.
But the risk of transmission can now be substantially reduced with antiretroviral medicines. Bruce Richman, who was diagnosed with HIV in 2003, says the treatments have changed his life. “For much of the time I had HIV, I isolated myself and had a sense of fear and shame,” he says. “Because I had a fear of transmitting HIV, I feared getting close to romantic partners.”
But that changed in 2012, when Richman’s doctor informed him that his antiretroviral treatment had reduced the amount of HIV in his blood to undetectable levels. The news was a revelation and Richman realised he no longer needed to hide.
Keen to spread the word, he started a campaign to publicise the life-changing effects of antiretrovirals and their impact on transmission rates. He called the campaign U=U (Undetectable = Untransmittable). His aim was to change the way people understand what an HIV diagnosis means, encourage those who are infected to keep up with their treatments and help lift the enduring stigma of HIV. “It improves the lives of people with HIV, and opens up social, sexual and reproductive lives that we didn’t think were possible,” says Richman.
“Eliminating AIDS as a public health threat by 2030 is potentially achievable”
Since 2016, the U=U campaign has teamed up with 570 other organisations in 71 countries to share the message. “In most of these countries people have been taught to fear HIV and people with HIV,” says Richman. “Now we’re turning a corner.”
The impact of this and other prevention strategies and campaigns has begun to reduce new infection rates. In 2016 in London, four sexual health clinics saw a 40 per cent fall in new HIV infections among gay men compared with 2015. And the number of new diagnoses in San Francisco has dropped by more than 50 per cent since 2006, in large part because of this “treatment as prevention” approach, also known as TasP.
But more work is needed, for example, on a vaccine. For some other viruses, vaccines work by mimicking the biochemistry of people who seem to be naturally protected from infection. “For HIV, we don’t have a good naturally protective correlate to work with,” says Lundgren.
Another difficulty is the lack of a good animal model for human HIV infections. Potential vaccines that show promise in monkeys infected with the similar simian immunodeficiency virus (SIV) have not been successful in human clinical trials.
There are also hopes for an HIV cure, but this has been harder to come by than expected. The main problem with trying to cure HIV is that there is a latent reservoir of the virus in the body.
That is why the leading strategy in the hunt for a cure is the “kick and kill” approach. This aims to kick HIV out of cells that act as a reservoir and then kill the virus.
While focusing on such scientific problems to make a cure a possibility in future, researchers at pharmaceutical company Gilead are also making progress when it comes to the potential for longer-acting treatments. At the moment, antiretroviral drugs must be taken on a daily basis and this can prove difficult for some.
Winston Tse, a senior scientist at Gilead, is working on a treatment that looks to be particularly potent and could take the form of a long-acting injection. He and his colleagues have set their sights on a protein that surrounds and protects the HIV RNA genome which is essential to viral life including its ability to infect new cells. The team is developing compounds that interfere with this protein and so inhibit the ability for the virus to replicate.
“Such a treatment could help with compliance, as well as lessening the emotional burden of taking daily HIV treatment,” says Tse.
It is this focus on prevention and treatment that make the UNAIDS goal potentially achievable – eliminating AIDS as a public health risk by 2030. “I would love a cure, but I’m investing my time into the strategy of testing, treating and prevention, because I think that’s the way to end this epidemic,” says Richman.
Lundgren agrees. “We have the tools, we have the drugs, we have the tests,” he says. “If we push resources, we can control it.”