HIV update - 19th June 2019

Australian man clears HIV

Researchers have identified a patient who appears to have spontaneously cleared his own HIV infection without any medication, many years after he was first infected.

However, the Australian man appears to have a unique combination of fortunate circumstances that only serve to show how difficult it is to eliminate HIV infection once it is established.

He was an ‘elite controller’, in other words one of the rare individuals who could maintain an undetectable viral load without medication. More specifically:

• The virus he was infected with lacked a piece of DNA that encodes a viral gene called nef.
• He had only one copy of the gene that peppers the surfaces of CD4 cells with the co-receptor molecule CCR5, making it harder for new CD4 cells to be infected with HIV.
• His CD4 cells had a very potent and specific response to a particular signal of viral infection.
• He had two cellular immune genes that ensured his response to HIV was particularly efficient, HLA-B57 and HLA-DR13.
• He had a strong and broad CD8 cell response to HIV-infected cells.

So a very specific chain of characteristics had to come together and act sequentially to ensure that the immune response to what was already a weakened virus in one person’s system was strong, specific and fast enough to do what has never been seen before: enable someone to spontaneously clear all the HIV from his body, without the need for medicine.

The researchers warn that we do not yet know if the same characteristics could be recreated in other people with HIV by artificial means such as genetic engineering and vaccines. But the case is a ‘proof of concept’. It shows that spontaneous cure or profound remission of HIV can happen and this will spur cure researchers on to make it happen more often.

For more information, read NAM’s factsheet ‘The search for an HIV cure’.

Treatment interruptions in children

Some children and young people find ongoing adherence to HIV treatment difficult. Although taking a break from treatment is not generally recommended, some people may stop taking their medication for a few weeks or months – researchers in 17 countries found that 12% of children and young people had done so. This was usually the child’s own decision.

The researchers wanted to assess the impact of these treatment interruptions on the health of the children’s immune systems. Stopping treatment allows HIV to replicate and damage the immune system, but some previous studies suggested that after restarting HIV treatment, children’s immune systems recover quite well – better than adults’ do. To better understand the recovery of the immune system, researchers measured the percentage of white blood cells that are CD4 cells (known as the CD4 percentage).

They found that two years after restarting treatment, the average CD4 percentage was at the same level as it was before stopping – in other words, there didn’t seem to be a long-term loss of immune function.

Of course this is an average, and some children did better than others. The younger the child was, the more likely it was they would have a good immune recovery. Also, children who previously had a strong immune system (their CD4 percentage had never fallen below 25%) were in a better position to bounce back. And the shorter a treatment interruption was, the better the recovery.

It’s helpful for doctors to know which children and young people are less likely to have a good recovery. They may need to restart HIV treatment promptly if their CD4 percentage drops too far during a treatment interruption. For this reason, regular blood tests during a treatment break are important.

For more information, read NAM’s booklet ‘HIV & children’ and factsheet 'Treatment breaks'.

Simpler treatment for those with resistance

If you have already been through a few different HIV treatment regimens, have developed resistance to several medications and need to change treatment again because it is not working, the options can be limited. It can be challenging to find enough drugs that are still effective to make up a combination that will supress HIV.

In this situation, guidelines recommend switching to a regimen that includes two, but preferably three, new drugs. It may also include drugs known as nucleoside reverse transcriptase inhibitors (NRTIs or nukes). Although this drug class has been the backbone of HIV treatment since the mid-1990s, these drugs do sometimes have side-effects.

Researchers wanted to see if the NRTI drugs could be left out of the drug combination in these circumstances. Their study was open to treatment-experienced people taking a protease inhibitor-based regimen and experiencing virological failure. The participants had virus that was sensitive to at least three antiretrovirals and were randomised to receive a new regimen that omitted or added NRTIs. The choice of other drugs was individualised and based on resistance testing.

After almost two years, results were comparable in both groups. The researchers say that people experiencing virological failure can safely omit NRTIs from a future regimen if they have three new agents available. 

For more information, read NAM’s factsheet ‘Changing HIV treatment’.

Contraception

For many years, there have been concerns over whether contraceptive injections such as DMPA (Depo Provera) raise women’s risk of acquiring HIV. A number of studies in African countries had previously shown higher rates of new HIV infections in users of contraceptive injections, but the way those studies had been done did not allow researchers to know whether the greater number of infections were to do with the hormonal contraceptive itself or some other factor.

So they designed a more robust study, which randomly assigned almost 8000 HIV-negative women to three different contraceptive methods, in order to find out. The results are reassuring – there were no differences in HIV risk according to the contraceptive method, and all the methods evaluated were safe and highly effective at preventing pregnancy.

For more information, read NAM’s factsheet ‘Contraception’.