FOR PEOPLE WHO inject drugs, taking a tablet every day could half their chance of contracting HIV.

The first trial to assess whether preventative treatment with HIV drugs could affect rates of HIV infection in people who inject drugs has found that daily tablets of tenofovir, an anti-retroviral drug, reduced HIV incidence by 49 per cent compared to  a placebo, according to new results published Online First in The Lancet.

Over 2,400 participants at 17 drug treatment clinics in Bangkok, Thailand were recruited and 1,204 of the participants were assigned a daily oral dose of tenofovir, while 1,209 were assigned a placebo. All trial participants were offered monthly HIV testing and risk-reduction counselling and services, plus access to drug rehabilitation treatment.

Participants were followed for four years and results showed that 17 participants in the tenofovir group became infected with HIV, compared to 33 in the placebo group, indicating a reduction in HIV risk of 49 per cent.

It was also found that antivirals worked best where participants adhered closely to the prescribing regime.

Worldwide, one in 10 new HIV infections are thought to be caused by injecting drug use, but in some regions, such as eastern Europe and central Asia, rates are far higher, with up to 80 per cent of new HIV infections caused by injecting drug use.

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