HIV-negative people who are at high risk of infection can reduce their chances of contracting the disease by taking antiretroviral drugs, a new study suggests.
Research published in medical journal The Cochrane Library this week found that the use of antiretroviral therapy as pre-exposure prophylaxis could dramatically reduce the risk of infection.
In the latest update of a systematic review, researchers found that uninfected people who were in relationships with HIV-infected partners were at much lower risk of becoming infected with the virus if they regularly used antiretroviral therapy.
In the study, researchers analysed data from six trials that tested the protective effect of daily doses of the oral antiretroviral drug tenofovir disoproxil fumarate (TDF), with or without emtricitabine (FTC), compared with a placebo or intermittent use.
The trials involved 9 849 high-risk individuals, including men who have sex with men, partners of HIV-infected people, sex workers and people who have multiple sexual partners.
Data from four of the trials and a total of 8 813 people showed that giving TDF plus FTC reduced the risk of HIV infection by about 50 percent, from 37 in 1 000 to 19 in 1 000.
Data from two trials and a total of 4 027 people showed that TDF alone reduced the risk of HIV infection by nearly two-thirds, from 26 in 1 000 to 10 in 1 000.
One of the authors, Dr Charles Okwundu of Stellenbosch University’s Centre for Evidence-Based Health Care, said that while the use of antiretroviral therapy as pre-exposure prophylaxis remained controversial due to drug resistance, toxicity and side effects, data showed there were benefits. “Our findings suggest that antiretroviral drugs can reduce the risk of HIV infection for people in high-risk groups. However, in the search for highly reliable HIV-prevention strategies, it is important to determine how pre-exposure prophylaxis can best be combined with existing programmes, as no strategy is likely to be 100 percent effective.”
He said it was important to establish whether the use of antiretroviral therapy as prophylaxis was practical, because it might encourage people to indulge in riskier behaviour, thereby increasing overall risk of infection.
Others raised concerns about the use of antiretroviral therapy as pre-exposure prophylaxis in SA.
Mark Heywood, executive director of SECTION27, was cautious, saying it could have unintended consequences in an SA context.
“There may be an argument for policy consideration for high-risk groups, but it would be dangerous to consider broad use of antiretrovirals as prevention.
“It may lead to drug resistance and risky behaviour… I think for now we need to concentrate on traditional ways of prevention.” - Cape Argus