Cocktail of drugs stops HIV in its tracks: Treatment is 93% successful in preventing virus being transmitted through sex
- Antiretroviral therapy (ART) is successful in stopping HIV being passed on
- Involves those wiht HIV taking at least 3 drugs to suppress the virus
- When the treatment failed it was because it hadn’t been taken correctly
- Experts say other preventative drugs should be given to partners too
A cocktail of drugs can stop HIV being transmitted through sexual intercourse, researchers claim.
A combination of drugs known as antiretroviral therapy (ART) stops HIV from being passed on from infected men and women to their uninfected partners, the results of a landmark study show.
Antiretroviral therapy (ART) consists of the combination of at least three antiretroviral (ARV) drugs to suppress the HIV virus and stop the progression of the disease.
Researchers found the drugs were able to reduce the transmission of the virus by 93 per cent in couples assigned to ART treatment.
A cocktail of drugs known as antiretroviral therapy can stop HIV from being passed on from infected men and women to their uninfected partners, a landmark study shows. HIV particles are shown under the microscope
The ‘viral load’, the amount of HIV in the blood, was also suppressed by the drugs.
Reducing the viral load lowers the risk of the person becoming ill because of HIV.
Dr Myron Cohen, director of the Institute for Global Health and Infectious Diseases, said: ‘These findings demonstrate that antiretroviral therapy, when taken until viral suppression is achieved and sustained, is a highly effective, durable intervention for HIV prevention.
Dr Cohen, who is also of the University of North Carolina, added: ‘The trial was designed to address two questions: whether providing antiretroviral therapy to an HIV-infected person would prevent HIV transmission to a sexual partner, and whether earlier antiretroviral therapy offered long-lasting health benefits, and the answer to both is a resounding yes.’
The study, known as HPTN 052, began in 2005 and 1,768 couples where one partner was infected with HIV while the other was not, were recruited.
The majority of the couples (97 per cent) were heterosexual.
HIV-infected partners were assigned to start ART at the beginning of the study, called the ‘early’ arm, or later in the study, called the ‘delayed’ arm.
Those on the delayed arm started ART when their bodies’ immune systems were declining.
In 2011, an provisional review of the study data showed a 96 per cent reduction of HIV transmission within the couples assigned to early ART, which was considered a major breakthrough finding.
WHAT IS ANTIRETROVIRAL THERAPY?
Antiretroviral therapy (ART) consists of the combination of at least three antiretroviral (ARV) drugs to maximally suppress the HIV virus and stop the progression of HIV disease.
Huge reductions have been seen in rates of death and suffering when use is made of this type of treatment, particularly in early stages of the disease.
Since 2013, WHO also recommends the use of antiretroviral drugs for the prevention of HIV infection, particularly for pregnant women, young children, and key populations exposed to HIV risk.
Source: World Health Organization
After the release of the results, all participants in the delayed ART arm were offered the opportunity to begin ART, and the study continued for four more years.
By the end of the study, 1,171 couples remained in follow-up.
And the final results show a 93 per cent reduction of the virus being transmitted.
In fact, researchers noted there were only eight cases of HIV transmission within couples after the HIV-infected partner was given ART.
And four of these eight cases were diagnosed soon after ART treatment began and so they believe the virus was probably transmitted before the drugs suppressed the virus in the HIV-infected partner.
And the treatment may have also failed because the people in the study either did not take their antiretroviral drugs as prescribed, or had a strain of HIV that resisted or acquired resistance to one or more of the drugs in their treatment regimen.
The researchers also revealed interesting findings about the relationship between viral load, viral suppression, treatment failure and drug resistance.
It took longer to suppress the virus in people who began with a relatively high viral load (a high level of HIV in the blood) at the start of treatment, they found.
This, in turn, was associated with both treatment failure and the treatment failed more quickly.
They also found that those who had a higher viral load when they joined the study, and for whom treatment failed, were more likely to develop resistance to their antiretroviral drugs.
More research is needed to understand this association, the researchers said.
‘These results have important implications for programs seeking to combine other HIV prevention measures with treatment as prevention,’ Dr. Cohen said.
He added programs to prevent and treat HIV should make ‘special efforts’ to minimise the transmission of HIV before the virus has been suppressed.
They should also aim to maintain suppression of the virus through ART treatment, and to identify and address failures of the treatment if it occiurs.
‘In the setting of such programs, special efforts should be made to minimize HIV transmission risk before viral suppression has been achieved, to maintain suppression on ART, and to identify and address ART failure.’
The results were reported at the 8th International AIDS Society (IAS) Conference on HIV Pathogenesis, Treatment and Prevention in Vancouver, Canada.
Give partner of people with HIV preventative drugs to reduce risk of infection, say scientists
Drugs to protect partners of people with HIV have been shown to be effective, yet they are not routinely prescribed, scientists warn.
Experts say a treatment which protects people against contracting the virus, known as pre-exposure prophylaxis, or PrEP, works well and carries minimal side effects.
The practice means that a healthy person who engages in sex with an HIV-positive partner takes anti-retroviral drugs daily as a preventive measure to ward off HIV.
Pre-exposure prophylaxis, in which is a healthy person who engages in sex with an HIV-positive partner takes anti-retroviral drugs daily, is a ‘game changer’ in preventing the spread of HIV, scientists say (file photo)
And yet, despite studies showing its success, it is far from becoming routinely prescribed, scientists say.
‘Pre-exposure prophylaxis (PrEP) is a game changer’ in preventing the spread of HIV, Dr Chris Beyrer, co-chair of the International AIDS Society (IAS) science conference in Vancouver.
He added: ‘The data is overwhelming… it works when it’s taken.’
At the conference, scientists released results on PrEP in several small studies of people at a high risk of contracting HIV, mostly due to sexual behavior, in Brazil, the United States, and Botswana.
The research showed that when PrEP is used correctly, it reduces HIV infection and is well-tolerated.
But several scientists said use of PrEP is far from becoming standard policy, and so remains an individual decision for people considered at high risk.
The therapy is also relatively new. The US Food and Drug Administration only approved use of the drug tenofovir (Truvada) for adults at high-risk, in combination with safe sex practices, in 2012.
An antiretroviral drug called Truvada costs just £400 a month, whereas a lifetime of HIV treatment costs the NHS up to £350,000 per person, the Terrence Higgins Trust warns
Dr Michael Brady, medical director of the Terrence Higgins Trust, said given the positive results of the study, introducing PrEP treatment makes financial sense and could eradicate HIV.
He said: ‘The success seen in Brazil, the United States, and Botswana has been mirrored here in England. In February this year, the PROUD study reported that PrEP reduced the risk of HIV infection by 86 per cent for gay and other men who have sex with men (MSM), when delivered in sexual health clinics in England.
‘On the basis of the PROUD results we would only need to treat 13 men for a year to prevent one HIV infection.
He added: ‘From a cost perspective, it is hard to see how PrEP would not be value for money. Truvada [an antiretroviral drug used in PrEP treatment] costs just over £400 a month, and the price will drop significantly when the drug comes off patent.
‘People will not need to take PrEP for ever, nor will they necessarily take it all the time, whereas HIV requires lifetime treatment that currently costs the NHS up to £350,000 per person.
‘PrEP could be the treatment to stop HIV, and Terrence Higgins Trust will campaign until the Government, NHS England, and local authorities agree to use it to place HIV firmly in the past.’