"Kick and kill" HIV cure showing promise
In 2014, a multi-university team of researchers in the UK undertook a search for the holy grail in HIV/AIDS treatment: a cure. At the time, they reported that the results from their "kick and kill" approach would be available in early 2017 but, as recently reported in The Sunday Times, it seems as though they're a bit ahead of schedule. The HIV virus has completely vanished from the bloodstream of a 44-year-old man who is one of 50 people who participated in the trial. Although more time is needed to confirm whether the result is from the new approach or from standard anti-HIV drugs that the patient was taking, the implications of the research are encouraging.
When HIV takes hold inside a body, some of it is active and can be spotted by the body's immune system and by medication known as antiretroviral therapy or ART drugs. Another portion of the virus, however, can hide inside cells in a dormant state and create what is known as the HIV reservoir. This cache of cells, in which the virus has knitted itself into a patient's DNA, has thus far been able to resist treatment and prevent doctors from completely eradicating it from an infected person.
The "kick and kill" method trialed in the study involves drugs called HDAC inhibitors, which have traditionally been used to combat cancer. These drugs activate the dormant HIV (the "kick") which can then be attacked by the ART drugs (the "kill"), while at the same time, the body's immune system is boosted by an HIV vaccine. The hope of the multi-pronged attack is that it can completely eliminate, not just knock back, the HIV infection in patients.
So far, the fact that the virus is completely absent from the anonymous study participant, who's a social worker, could mean that the treatment is working – or it could simply be that the virus is undetectable because of the ART drugs the patient is taking, which could also mask it from tests.
If the former is the case, the results are certainly promising. Yet Sarah Fidler, a consultant physician at Imperial College London who is co-leading the research with Dr John Frater at Oxford, warns that there is still work to be done to declare a cure for HIV, a disease that currently affects 36.7 million people.
"It has worked in the laboratory and there is good evidence it will work in humans too but we must stress we are still a long way from any actual therapy," she told The Sunday Times. "We will continue with medical tests for the next five years and at the moment we are not recommending stopping ART but in the future depending on the test results we may explore this."
In addition to Oxford and Imperial College London, the other participating universities are King's College London, the University of Cambridge and University College London. Together they form the CHERUB Collaboration, which stands for the Collaborative HIV Eradication of viral Reservoirs: UK BRC. The organization, which pushed the timetable for the study results to 2018, shares Fidler's caution, having released this statement on their website today:
Our study will report in 2018, and until then we will not know if the intervention has had an effect. We do know from our first participant that the intervention was well tolerated. This is the first time that this combination has been given in a clinical trial, which we hope will be the first of many collaborations exploring HIV cure between our five universities and NHS hospital trusts, supported by the NIHR.
An important clarification is that all participants involved in the study will be expected to have no HIV in their blood because they are receiving antiretroviral therapy – these are the standard drugs we use to treat HIV. This does not mean they have been cured as some headlines have suggested. This does mean that their immune systems will recover and that they will not transmit the virus. We look forward to reviewing the final results of this ground-breaking study, but until then should emphasise that we cannot yet state whether any individual has responded to the intervention or been cured.