New UCLA-led research suggests that antiretroviral drugs called TAF and TDF directly reduce energy production by mitochondria, structures inside cells that generate the power that cells use to function. Both drugs led to reduced cellular oxygen consumption rates, a measure of the ability of the mitochondria to produce energy, compared with controls. But in combination with other antiretrovirals, TAF appeared to result in a larger energy reduction than TDF did. Whether this is a cause for concern is not known at this point.
The antiretroviral drugs tenofovir alafenamide (TAF) and tenofovir disoproxil fumarate (TDF) are used to treat HIV and hepatitis B infection in millions of people around the world. These drugs are also used as pre-exposure prophylaxis (PrEP) against HIV in uninfected people.
Using both a human clinical trial and experimental lab studies, the researchers assessed the impact of TAF and TDF in combination with other antiretrovirals on the ability of blood immune cells to make energy. In the clinical trial, 26 people with HIV switched antiretrovirals over nine months and the researchers assessed how the drugs affected their cells’ energy production. The investigators confirmed these findings experimentally in the lab by directly adding the drugs to healthy immune cells and analyzing their impact on the cells’ metabolism.
