Several human immunodeficiency virus (HIV) patients all over the world are becoming resistant to a key antiretroviral drug called tenofovir, and it's all because of inconsistent and improper drug use, a new study revealed.
Unfortunately, experts say the spread of HIV-drug resistance could spell trouble for the prevention of the virus, which causes AIDS, and for the treatment of the illness.
According to a report published in the journal Lancet Infectious Diseases, more than half of people who still have uncontrolled HIV despite ongoing treatments turned out to have an HIV strain that is resistant to tenofovir.
Led by Stanford University's Dr. Robert Shafer, the group of researchers has found that HIV strains in Africa were much more resistant to tenofovir than HIV strains in Europe. About 60 percent of HIV patients in Africa had become tenofovir-resistant, a number definitely higher than that of Europe, which had 20 percent.
This raises concerns over the right efforts to fight the spread of HIV-drug resistance. The report suggests that treatment and monitoring of HIV patients need to be significantly improved, and that surveillance needs to be increased.
Aside from HIV, tenofovir is also used to treat hepatitis B. Researchers say developing resistance to the antiretroviral drug is a very large loss.
University College London's Dr. Ravi Gupta, one of the researchers of the study, says the availability of second-line drugs is increasing, but these drugs are a bit more expensive than tenofovir and have more side effects associated with them.
Gupta says people develop HIV-resistance to tenofovir in two ways: either they don't take the drug as intended, causing HIV to mutate, or they are infected by someone who is resistant to the drug.
"If the right levels of the drug are not taken, as in they are too low or not regularly maintained, the virus can overcome the drug and become resistant," says Gupta. "Tenofovir is a critical part of our armamentarium against HIV, so it is extremely concerning to see such a high level of resistance to this drug."
Gupta adds that what they need are early warning systems and to act early on what they find. Meanwhile, further studies are being conducted to determine how HIV became resistant to tenofovir.
Photo : National Institute of Allergy and Infectious Diseases | Flickr