Scientists in the United States said they have developed a quick method to test anti-AIDS treatments that could improve their effectiveness and prevent drug resistance.
Until now doctors were unable to determine whether a particular combination of drugs was fighting HIV until four to eight weeks after the treatment began.
But scientists at the National Institute of Allergy and Infectious Diseases (NIAID) and the National Cancer Institute (NCI) can now tell if drugs are working in the first week.
"We now have a quick, simple and direct way of telling if the drugs are working," said Michael Polis, an infectious disease specialist at NIAID.
"In addition to heading off HIV drug resistance, this approach might also avoid exposing patients to the toxicities of anti-retroviral drugs that aren't effective for them," he added in a statement.
Scientists usually determine how well drugs are working by measuring the amount of the virus in the blood, or viral load, four to eight weeks after treatment started.
Polis and his team, whose research is reported in The Lancet medical journal, discovered if a patient's viral load had dropped 50-fold or more by the sixth day of treatment they had a good chance of long-term success with the treatment.
The test is no guarantee a person will get better, but it predicted the outcome of the therapy in 95% of cases.
About 17 different anti-retroviral drugs are used in different combinations to fight the virus that causes AIDS.
The finding could improve the use of the current crop of drugs until better therapies are developed.
"We are currently trying to identify additional parameters that may help to more accurately evaluate an individual's response to therapy," said Dr Dimiter Dimitrov of the NCI.
More than 21 million people have died of AIDS since the start of the epidemic 20 years ago.
An estimated 36 million people are living with HIV/AIDS, including more than 25 million people in sub-Saharan Africa.
© Reuters
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