More tracking of HIV drug resistance vital – WHO
(SciDev.Net) - Countries must step up their monitoring of resistance to antiretroviral drugs for HIV to ensure that lifesaving therapies remain effective, a World Health Organization (WHO) report urges.
The WHO’s latest HIV Drug Resistance Report was released ahead of World AIDS day (1 December). HIV, the virus that causes AIDS, is one of the world’s most serious public health challenges with around 37.7 million people worldwide affected by the virus in 2020, according to UNAIDS. Resistance to the drugs used to fight it is rising.
The WHO recommends an urgent change in first-line HIV drugs where drug resistance among ten per cent of adults beginning therapy has been reached in a country, for treatments such as nevirapine and efavirenz. These treatments belong to a group of drugs called non-nucleoside reverse transcriptase inhibitors (NNRTI). The report says an increasing number of countries are reaching the ten per cent threshold for pretreatment resistance to NNRTIs and people who have had previous exposure to antiretroviral drugs are three times more likely to demonstrate resistance to this class of drug.
Pretreatment drug resistance, or PDR, is defined by the WHO as resistance that is detected among people either newly initiating or reinitiating first-line antiretroviral therapy.
Nitika Pant Pai, associate professor at the department of medicine at McGill University, in Montreal, Canada, told SciDev.Net: “There was always this underlying fear, in the HIV community, about pre-treatment [drug resistance] crossing that ten per cent threshold, and this report basically
confirms our fears.”
The WHO says the findings support the need to speed up the transition to regimens containing the drug dolutegravir — which is more effective and less prone to resistance — in countries that continue to use NNRTI-based antiretroviral therapy, especially for children.
In surveys conducted in SubSaharan Africa, pre-treatment drugresistance was observed in about half of infants newly diagnosed with HIV and there was a high prevalence of pre-treatment drug resistance to nevirapine and efavirenz, the report says.
The WHO has recommended use of dolutegravir as the preferred firstand second-line of treatment for all population groups since 2019. It says it is more effective, easier to take, and has fewer side effects than other drugs currently in use.
Jorge Martinez-Cajas, assistant professor at the department of medicine at Queen’s University, in Ontario, Canada, said it was encouraging
that more countries were effectively switching to dolutegravirbased regimens and the trend should be accelerated. “This switch will likely preserve the usefulness of antiretroviral treatments throughout this generation,” he said.
The WHO report also looked at the use of pre-exposure prophylaxis (PrEP), a prevention method where HIV-negative individuals with increased risk of HIV infection take specific drugs to protect themselves against the infection.
“Although PrEP users have a substantially reduced risk of acquiring HIV, individuals who become infected are at risk of having drug-resistant HIV,” it said. According to the WHO, PrEP should be conducted along with surveillance of HIV drug resistance.
The report also suggested that, for HIV, substantially suppressing the load of the virus in populations undergoing antiretroviral therapy prevented the emergence of drug resistance.