This Week in HIV Research: Determinants of Cognitive Impairment, and Discovery of 'Teenage' Broadly Neutralizing Antibody
This week, a new study highlights some of the determinants of cognitive impairment among middle-aged men living with HIV. Another study discovers an immature antibody that may provide clues for developing broadly neutralizing antibodies capable of inhibiting HIV. Also, Descovy, a new drug containing the updated version of tenofovir -- tenofovir alafenamide (TAF) -- was approved by the FDA. To beat HIV, you have to follow the science!
A number of factors, not all of them related to HIV, may reduce cognitive performance in people living with HIV, including more severe immune deficiency, cardiovascular/metabolic factors, cannabis use, and symptoms of depression, according to a study published in AIDS.
Researchers followed 103 individuals living with HIV who were on treatment and had undetectable viral loads for at least one year, along with 74 HIV-negative controls. All study participants were at least 45 years old and male.
Neuropsychological assessments were conducted by trained neuropsychologists and evaluated six areas commonly affected by HIV-associated cognitive impairment: fluency, attention, information processing speed, executive function, memory, and motor function.
Based on these assessments, cognitive impairment and performance were then determined by multivariate normative comparison (MNC), which is a statistical method of analysis. In total, 17% of the HIV-positive group was diagnosed with cognitive impairment.
Using MNC as a continuous variable for analysis, the researchers found that the determinants for decreased cognitive performance included:
- Cannabis use.
- History of prior cardiovascular disease.
- Impaired renal function.
- Type-2 diabetes.
- Having an above-normal waist-to-hip ratio.
- Symptoms of depression.
- Lower nadir CD4+ cell count.
"These [determinants] are likely to gain increased importance as the population of people living with HIV continues to age," the researchers concluded.
Researchers at the Scripps Research Institute have identified for the first time an immature or "teenage" version of a broadly neutralizing antibody (bNAb) capable of inhibiting HIV, according to a study published online ahead of its release in the journal Immunity.
Broadly neutralizing antibodies continue to be discovered and studied, primarily in the development of an HIV vaccine, but also as part of a potential treatment strategy.
The teenage antibody came from a Chinese individual living with HIV who is also an elite controller, a person living with HIV who can maintain a very low viral load without treatment.
"This is actually the first example of how we can go back to the really early stage to see how this antibody lineage was born and can develop," said co-senior author Jiang Zhu, Ph.D., according to the study press release.
The discovery of this teenage antibody sheds light on the evolution of broadly neutralizing antibodies and further guides researchers in engineering an effective HIV vaccine.
On April 4, the U.S. Food and Drug Administration (FDA) approved emtricitabine/tenofovir alafenamide (F/TAF), which will be marketed as Descovy, in a fixed-dose combination for the treatment of HIV in adults and adolescents over 12.
Descovy is the third approved HIV drug to include TAF, which has been shown to have better bone and kidney safety than its predecessor tenofovir disoproxil fumarate (TDF, Viread). It essentially replaces the TDF in tenofovir/emtricitabine (F/TDF, Truvada).
Descovy is indicated to be used in combination with other HIV antiretrovirals; however, it is not indicated for use as pre-exposure prophylaxis (PrEP), according to the approval press release.