AIDS 2014: towards a cure
Leading scientists from around the globe gathered at AIDS 2014 today to discuss efforts and progress towards a cure for the virus and recent advances which suggest a ‘kick and kill’ approach at a cellular level may be having some success.
In a press conference chaired by Professor Francoise Barre-Sinoussi of the AIS joined co-chair of the 2014 AIDS conference Professor Sharon Lewin in suggesting that while a cure was unlikely at this stage long term remission was a possibility and a current goal for researchers.
Lewin, co-director at the Infectious Disease Unit at The Alfred said the focus of efforts for an HIV cure was currently on developing treatments leading to remission.
“We need much better tools to measure virus and better assays to show where the virus is hiding,” Lewin said. “The Mississippi baby and Boston case - both rebounded after stopping treatment and its show we not only have to tackle the virus but a good immune response to tackling the virus if it re-emerges.”
Lewin said although we know early treatment significantly reduces the amount of virus, she suggested in developing nations where access to treatment and testing is limited, most people get treated during long standing infections so there viral load is very high.
“With 80 percent of people with the virus in low income countries, we need efforts to engage low income countries in testing early, treating and searching for a cure,” Lewin said.
While many in the media have been disappointed by the rebound of the Mississippi baby in recent weeks (after previously having undetectable viral loads and no symptoms of an immune response relating to HIV, the virus has reappeared) Lewin and Barre-Sinoussi prefer to see it as an opportunity to learn more about the way HIV reacts.
It’s a sentiment shared by Dr Debbie Persaud, John Hopkins expert on paediatric HIV and a world-leading virologist who has been treating the Mississippi baby (now a toddler).
“We can learn a lot from this case,” Persaud said. “It is sobering news for us – but we have also never experienced a child who has been HIV positive, had treatment and then gone off treatment for 27 months with no sign of the virus.”
Persaud said they have also learned the virus can persist for years.
“And persist in a quiescent state n the absence of any immune response.”
Persaud also confirmed the child who rebounded has since seroconverted and is back on ART.
Dan Barouch, Professor of Medicine; Director, Center for Virology and Vaccine Research Beth Israel Deaconess Medical Center also spoke of some recent animals trials where similar results had shown that even when treatment was established very early on the retroviral therapy was still insufficient to ‘cure’ the virus.
The implications of these and similar studies suggest that even as soon as one is able to diagnose the virus - the virus reservoir has already been established – so strategies other than early ART need to be looked at to eliminate the last vestiges of the virus.
Danish researcher Dr Ole Schmeltz has been working on a way to reveal the virus at and kick it out of its hiding place.
In 2013 a new group of drugs, histone deacetylase (HDAC) inhibitors, traditionally used to treat leukaemia, had been shown to reactivate HIV from latency on a systemic level, and Schmeltlz has been working on a study with six patients to see if the inhibitors have the same response in patients.
Schmeltz will announce the preliminary results of his trial tomorrow – but if his kick and kill process works, it bodes well for helping to unmask the HIV cells that don't respond to standard treatment.
Professor Steven Deeks from the University of California’s Positive Health campaign said “Ole's data is the first evidence that we can identify the hidden reservoir and shock it out of its hiding place - and it will have a huge impact on the future. Once it comes out of it's hiding place - what do we do? Where does it live? How do we measure it? We’ll need bigger and better studies on shock and kill.”
“We have always thought once the virus gets in a cell and goes to sleep it is stuck forever - but these studies have shown you can wake it up and you can make enough virus to leave the cell - so then the cell will be visible to an immune response, so you could possibly get rid of it with a more potent drug.”