This Week in HIV Research: Early Treatment With Broadly Neutralizing Antibodies Suppresses SHIV in Monkeys
This week, a study finds that administering two broadly neutralizing antibodies very early on during infection helped monkeys achieve long-term viral suppression of simian HIV (SHIV). Another study finds that a targeted HIV testing campaign aimed at young men of color who have sex with men was more effective than other testing strategies. And high levels of drug resistance in Aruba raise concerns about issues with treatment guidelines. To beat HIV, you have to follow the science!
Early bNAb Treatment Achieves Extended SHIV Suppression in Monkeys
Very early infusions of two broadly neutralizing antibodies (bNAbs) achieved long-term viral control in macaque monkeys, a study published in Nature reported.
Researchers infected 13 animals with SHIV, the monkey version of HIV. Three days after seroconversion, the macaques were started on a two-week course of two bNAbs, 3BNC117 and 10-1074, a press release from the National Institutes of Health reported.
All animals suppressed SHIV below detectable levels well beyond the treatment period, for up to six months. Viral load then rebounded in most of the macaques, but six of the animals regained control of the virus without treatment five to 22 months after viral rebound. This second round of undetectable viral loads lasted between five and 13 months.
Four more monkeys had detectable, but very low, viral loads. By contrast, once antiretroviral therapy was discontinued, SHIV rebounded quickly in macaques who had received this standard treatment starting three days after infection. The bNAb combination is also under investigation in human trials, according to a Rockefeller University press release.
Targeted HIV Testing Strategies Most Effective at Diagnosing Young Men of Color
HIV testing strategies aimed at young people who are at risk for HIV diagnosed more young men of color who have sex with men than did routine community-wide HIV screenings, a study published in JAMA Pediatrics found.
The study found that men who are not living with HIV were also more likely to be connected to prevention services, including pre-exposure prophylaxis, when reached by a targeted approach than when they were tested at community-wide screening sites. Over 3,300 young people were tested for HIV during this demonstration project. About 6% of youths at targeted testing sites found out that they live with HIV, compared to 0.1% at universal testing sites and 2.1% at sites that used both universal screening and targeted outreach. Targeted strategies included mobile testing units and youth-friendly drop-in centers.
An accompanying editorial noted that such focused efforts may not always be possible. It advocated a combination of universal testing and targeted outreach to identify the greatest number of people living with HIV, including young men of color, and to link them to care.
Transmitted Drug-Resistant HIV Levels May Compromise Treatment in Aruba
High levels of drug resistance detected in treatment-naive people living with HIV in Aruba raise concerns of widespread problems with the World Health Organization's (WHO) recommended first-line antiretroviral regimen, a study published in Clinical Infectious Diseases reported.
Researchers analyzed all available data on resistance testing among people newly diagnosed with HIV in Aruba between 2010 and 2015. Such testing was performed in about half of the 104 people who were diagnosed with HIV during that period. Overall, around a third of study participants had been infected with a drug-resistant strain of the virus. Viral resistance to non-nucleoside transcriptase inhibitors (NNRTIs) based on mutation K103N rose to 45% among those diagnosed in 2015.
Further examination revealed that some of the viral strains were linked to surrounding countries, raising the possibility of a wider geographic spread of NNRTI-resistant virus. WHO recommends treatment based on the NNRTIs tenofovir (TDF) or AZT. In the Caribbean, such regimens may be compromised by the high prevalence of transmitted resistance to these drugs, the researchers warn.