ISLAMABAD, Dec 1 (Pakistan Point News - APP - 01st Dec, 2016 ) : Patients whose human immunodeficiency virus (HIV) strains developed a resistance to older generation drugs are also resistant to modern drugs, a new study has found. Resistance to a drug typically occurs when patients doesn't take their medication regularly enough, and for first-line treatments to work, patients generally need to take their medication 85-90 per cent of the time. The findings revealed that HIV can be resistant to many different drugs simultaneously.
In the study, the researchers found that 16 per cent of people who stopped responding to modern first-line treatments had HIV mutations associated with resistance to an older generation of drugs called thymidine analogues. Among patients with a thymidine analogue mutation, 80 per cent were also resistant to tenofovir -- the main drug in most modern HIV treatment and prevention strategies. For the study, published in The Lancet Infectious Diseases, the team studied 712 HIV patients across the world whose HIV was not controlled by antiretrovirals.
"We were very surprised to see that so many people were resistant to both drugs, as we didn't think this was possible," said lead author Ravi Gupta, Professor at University College London. Mutations for thymidine analogue resistance were previously thought to be incompatible with mutations for tenofovir resistance, but now HIV can be resistant to both at once, the researchers said.