Please could you tell us a little bit about the history of HIV/AIDS therapy?
The anti-HIV drugs, also known as anti-retroviral therapy, came about in the mid ‘90’s. These involved using at least 3 different drugs together. These therapies lead to a dramatic change for patients with HIV infection. Patients literally got off their death bed with these medications.
Up until the mid ‘90’s HIV diagnosis was a universal death sentence; but once the anti-HIV drugs became available, HIV became a chronic disease.
What is the main reason why we can’t cure the HIV virus?
The current drugs stop the virus from infecting new cells, but the problem is that HIV can hide in certain cells and establish something called a latent infection. This type of infection occurs when a virus enters into a cell and enters the patient’s DNA. It then effectively goes to sleep there and hides; however, it can come out at any time.
When the virus is hiding, or in the so-called latent state, the drugs can’t act on that virus and the immune system does not see the infected cell.
What research have you done into trying to overcome this problem?
We have been doing a lot of research on how the virus gets into the DNA and the latent state. We have developed a way of studying that in the laboratory.
There are two ways you can get rid of the latent, or sleeping, virus. One way is to wake it up and get the virus to start coming out of the cell. Once it comes out of the cell it becomes visible to the immune system and visible to the drugs. We’re looking at ways to wake up that virus in the laboratory using a model we developed.
The other way is to look at ways to stop the virus getting into the DNA, i.e. to stop ways for latency to occur.
What impact on HIV/AIDS therapy do you think your research will have?
The long term goal is to find ways to get rid of the latent virus. If you could get rid of that, you could potentially safely stop anti-HIV drugs. At the moment you need to be on the anti-HIV drugs for life, because if you stop them the virus just re-emerges.
The impact could be finding a way to reduce the time someone has to take anti-HIV drugs for: from 50-60 years down to 4-5 years.
What future plans do you have for research into this area?
We’ve got lots of different projects in this area. We are looking at the different pathways the virus uses to get into resting T-cells. We’re also looking at which parts of the host cell the virus uses to get inside the resting cell and hide there.
We are looking at a range of different drugs and how effective they are at waking the virus up – either alone or in combination. The long-term goal is to test some of these in clinical trials.
What other research is currently going in to HIV/AIDS?
What we’re doing is looking for a cure. There are two other main areas of scientific research. One is related to finding a vaccine.
The other main area is trying to understand why people’s immune system doesn’t fully recover when you put them on treatment. People do well, i.e. their life expectancy almost returns to normal, but they are still at risk of other diseases, particularly those associated with ageing.
The International AIDS Conference 2012 has just finished, please could you give us a summary of this event?
It was the first time the meeting had been in the US for 22 years, because up until 2009 there was a travel ban for people with HIV. This meant that people with HIV could not visit the US. Consequently, it was a historic meeting in that sense.
There is a lot of optimism about the potential for the end of AIDS, or an AIDS-free generation. If we could treat a lot more people, then the treatment would stop HIV developing into AIDS.
At the same time, we learnt from a very important study last year that treatment also reduces someone’s infectiousness by 96%.
At the moment there are 33 million people infected with HIV. In poor countries, about 8 million of these people are on treatment and about 15 milliion need treatment. So we have a gap of 7 million people not receiving treatment who need it. If we could treat a lot more, at least 15 million if not more, we may have a very significant impact. By this I mean we could see the end of AIDS, and in addition transmission of the virus would be vastly reduced.
There was a lot of discussion about what it would take to achieve this. For example, how much money it would require; what it would require from local governments; what it would mean for health systems to allow many more people to get treatment.
There was also a lot discussion on cure. There was a 2-day workshop before the meeting started on HIV cure. At the meeting, a global strategy was also launched by the International AIDS society on cure.
The next conference, AIDS 2014, will be hosted in Melbourne. Why was Melbourne specifically chosen to host the conference?
The conference traditionally moves around to different locations. They tend to have a theme or a focus for each conference. The focus for the AIDS 2014 conference will be on the Asia-Pacific region.
This will be the first time the meeting has been in Australia. The last time it was in Asia was in 2004 when it was in Bangkok. The challenges in Asia are quite different to other parts of the world.
There are 4.2 million people living with HIV in Asia. In many countries in Asia the epidemics are in high risk groups, such as people who inject drugs; people who engage in sex work; MSM and so forth. Consequently, the challenges in Asia are different from Africa, for example, where there is a generalised epidemic.
The other benefits of hosting the conference in Melbourne are the outstanding research and track record we have in HIV in Australia, that Melbourne can physcially host 25,000 conference delegates and that we have very open policies for people with HIV.
What are the aims of the AIDS 2014 conference?
We are just starting to plan the AIDS 2014 conference. We had our first meeting in Washington. The field is changing rapidly, so I think our focus will be on how we are going with getting treatment out to people who need it.
There have been a lot of targets set by the UN for 2015, such as reducing infections in babies to zero and reducing new infections by 50%. The AIDS 2014 conference will be a time to reflect on whether we are getting close to those targets or whether we need to do something dramatically different to ultimately end AIDS.
How do you see the future of HIV/AIDS therapy progressing?
I think it is a really exciting time, we have excellent treatments and they are getting cheaper. This is allowing availability of drugs to increase in poor countries.
The real challenge now is how we get enough money to maintain and grow treatment access in all countries. There is also the challenge of making sure people stay on the treatments for life. These are both what we call the implementation challenges.
The scientific challenges are finding a vaccine and a cure. We really need both of these in order to see the end of AIDS.
Where can readers find more information?
www.AIDS2012.org has some great information, including videos, webcasts, summaries of the sessions and so forth.
About Professor Sharon Lewin
Professor Lewin is an infectious diseases physician and basic scientist. She is Director of the Infectious Diseases Unit at the Alfred Hospital; Professor of Medicine, Department of Medicine, Monash University; co-head of the Centre for Virology, Burnet Institute, Melbourne, Australia; and an Australian National Health and Medical Research Council (NHMRC) practitioner fellow.
She completed her medical training at Monash University, Melbourne; her specialist infectious diseases specialist training at the Royal Melbourne Hospital, Melbourne; her PhD in virology from the Burnet Institute, Melbourne; and her post-doctoral fellowship at the Rockefeller University, New York.
She is a past president of ASHM, the peak professional body that represents all clinicians and researchers working in HIV in Australia. She is currently a member of the Ministerial Advisory Committee on Blood Borne Viruses and Sexually Transmitted Infections, the peak advisory body to the Australian Government on blood borne viruses, and a member of the IAS international working group currently developing a global scientific strategy for HIV cure research as mentioned above.
She has received continuous research funding from the Australian NHMRC since 1993, as well as funding from the National Institutes of Health, American Foundation for AIDS Research and the Wellcome Trust. Her laboratory focuses on understanding how HIV persists in patients on antiviral therapy, strategies to cure HIV infection, biological determinants of immune recovery following antiviral therapy and the pathogenesis of HIV-HBV co-infection.
Sharon Lewin is the local co-chair of the XX International AIDS Conference (AIDS 2014), and together with the Melbourne Convention + Visitors Bureau (MCVB) and the Australasian Society for HIV Medicine (ASHM), was instrumental in securing this event for Melbourne.
Professor Lewin is one of seven researchers, and the only Australian, to be awarded a grant through the American National Institutes of Health (NIH) to aid research into a cure for HIV. Lewin made the discovery of how the virus enters resting cells and goes to “sleep” (what researchers call HIV latency), which was considered a major milestone in HIV research.
Lewin is also only one of two Australian scientists on the working group for the global scientific strategy ‘Towards an HIV Cure’ under the auspices of the International AIDS Society (IAS), which was launched at the XIX International AIDS Conference in Washington between 22 – 27 July 2012.