How far are we from a cure for HIV?
It's been decades since the discovery of the human immunodeficiency virus (HIV). Ever since its discovery, researchers have been working tirelessly to figure out the characteristics and inner workings of the virus to find a cure.
A definite, traditional cure has not yet been established, even though researchers and scientists consider two specific, yet expansive, methods as “cures”.
Functional vs. Sterilising
Researchers, scientists and doctors are currently working on these procedures, which are classified as "functional" and "sterilising" cures.
Professor Caroline Tiemessen, head of cell biology for the Centre for HIV and Sexually Transmitted Infections (STI) at the National Institute of Communicable Diseases (NICD) told Health24 that we are still a long way off from a complete cure.
“Achieving HIV remission may be possible for some, but we need a better understanding of who would benefit. It is clear that early treatment is not enough for most, and additional interventions need to be found.
“With regards to there ever being a cure for HIV and Aids, we would first need to define the HIV cure – complete eradication like the Berlin Patient versus HIV remission, as in a functional cure, which is sustained control of the virus to undetectable levels without antiretroviral drugs.
“Achieving HIV remission is the more feasible option, whereas achieving a complete cure is a major challenge,” said Tiemessen.
The case of Timothy Ray Brown, better known as the Berlin Patient, and his journey to recovery, caused a lot of speculation that the method used to treat his leukaemia, along with his HIV, might be the answer to curing HIV. The situation is however very complicated.
Brown received chemotherapy and a stem cell transplant, which is one of the methods in the category of sterilising cures.
Complexities of the sterilising cure
According to HIV/Aids information site Avert, there are four main areas of research which fall under the category of sterilising cures:
- The "shock and kill" method where the aim is to flush the virus out of reservoirs (areas in the body where it hides) and then to kill the infected cells.
- Gene editing which looks at changing the immune cells so that they cannot be infected by the HI virus.
- "Immune modulation" seeks out ways to permanently change the immune system so it’s better equipped to fight off HIV.
- Stem cell therapy, as used with the Berlin Patient, which aims to completely wipe out the infected immune system and replace it with a donor’s system. This method is the most complicated of all four.
Several methods appear to be promising, but there is no cure on the horizon. No traditional, conventional cures, as they are known.
Over the last few decades, ARVs have improved and the functional "cure" seems to be the most promising for the time being.
SA has done exceptionally well
Professor Salim Abdool Karim is the director for the Centre for the Aids Programme of Research in South Africa (CAPRISA), a designated United Nations Acquired Immunodeficiency Syndrome (UNAIDS) Collaborating Centre for HIV Prevention Research and a unit which conducts research for the South African Medical Research Council (SAMRC).
Abdool Karim told Health24 that South Africa didn’t really have access to treatment for HIV until 2004, but that the country has done exceptionally well in increasing ARV therapy to people living with the virus.
“SA has the largest ARV therapy programme in the world with approximately 4.2 million people receiving treatment. Although we can celebrate these achievements, there are still an estimated 2.9 million people in SA in need of ARV therapy,” said Abdool Karim.
Abdool Karim added that what was once a universally fatal disease can now be controlled with one pill, taken once a day.
ARV therapy has come a long way since its inception. It was once a drug, which, although it helped people living with HIV, brought with it a host of side-effects, making many people feel ill in other ways.
There may not be much hope for a sterilising cure, seeing that much research still needs to be done. Researchers, scientists and doctors are however making major strides in honing the functional cure.
“There has been a lot of progress with regards to finding a ‘functional cure’. This method does not focus on eliminating the virus from the body altogether, but rather on reducing the virus to such a level that it is undetectable.
“Research in this area has focused on post-ARV therapy sustained remission of viremia, whereby HIV patients are able to achieve suppression of the virus using monoclonal antibodies or other agents that control the infection and they no longer need to take daily ARVs,” said Abdool Karim.
HIV-associated illnesses on the decline
According the United Nations Acquired Immunodeficiency Syndrome (UNAIDS) report Right to Health recently released, 20.9 million people are ARV treatment, but there are 15.8 million people who are still in need of HIV treatment.
In 2000, a miniscule 90 people were receiving ARV therapy treatment in South Africa through the public sector, but as of mid-2017, 4.2 million people were accessing treatment and 2.9 million still needed to access treatment.
Dr Tendesayi Kufa-Chakezha, senior epidemiologist at the Centre for HIV and Sexually Transmitted Infections at the National Institute for Communicable Diseases (NICD) told Health24 that the country has done really well in managing HIV and HIV-related illnesses.
“Rates of HIV-associated illnesses, such as tuberculosis and cryptococcal meningitis have been going down over the years. According to Statistics South Africa, the number of HIV-related deaths have declined from an estimated peak of about 350 000 in 2005 to about 126 000 in 2016, largely due to the availability of ARV therapy and the growth in HIV treatment programmes,” said Kufa-Chakezha.
While many are hoping for a cure to be discovered, healthcare professionals and the government are urging people to continue being tested and for those who are infected to seek treatment immediately.
Many tools for achieving HIV prevention
Vast amounts of research are also being put into the HIV vaccine development, which has several ongoing clinical trials, but Abdool Karim said that even though there have been major advances in understanding HIV pathogenesis and the human immune system, several unique challenges remain before an effective vaccine is developed.
Efforts continue to be made to educate people about various aspects of the illness, in order to reduce the number of infections and the number of deaths. Dr Kufa-Chakezha says that even though the numbers are starting to decline, we still need to step up HIV prevention efforts, so people who are HIV negative stay that way.
Dr Kufa-Chakezha said: “There are many tools for achieving HIV prevention – abstaining from sex, reducing the number of sexual partners, correct and consistent condom use, male circumcision, HIV drugs for preventing infection – pre-and post-exposure prophylaxis and all require some behavioural change or action on the part of the users.
“We also need to test people more frequently so that people who have HIV infections are put on treatment as soon as they are tested. Doing this reduces the levels of the circulating virus and prevents onward transmission to others. We need to make sure people who are started on ARVs continue to take their treatment daily and keep the virus suppressed for their own health and to stop transmission to others.
“This requires HIV services that work well and address unique needs of people living with HIV, continuous supply of medication and individuals who are motivated to stay on the course. Lastly, we need to keep investing in the search for a vaccine and a cure.”