麻豆传媒

SEATTLE -- A universal "test and treat" strategy in African communities was associated with a 30% reduction in HIV after 3 years compared with standard of care, a researcher said here.

When trained community health workers went door-to-door to deliver HIV services, including testing and linkage to care, as well as treatment according to in-country guidelines, there was a significant reduction in the incidence rate of HIV versus standard of care (adjusted IRR 0.70, 95% CI 0.55-0.88, P=0.006), reported Richard Hayes, DSc, of the London School of Hygiene & Tropical Medicine in England.

However, in the most intensive intervention arm of the study, which also provided immediate access to antiretroviral therapy in addition to the other interventions, there was no significant difference compared with standard of care (adjusted IRR 0.93, 95% CI 0.74-1.18, P=0.51).

The results of this late-breaking study were presented at the Conference on Retroviruses and Opportunistic Infections.

In a separate interview prior to the conference, National Institute of Allergy and Infectious Diseases (NIAID) Director Anthony Fauci, MD, whose organization helped to fund the research, told 麻豆传媒 that the fundamental principle of studies like this is to show "in the field that [test-and-treat] actually works when you do it," and that this proactive strategy can potentially have an impact on HIV incidence in a community.

The (PopART) study, also called HPTN 071, had a total study population of around one million, which Hayes described as "the largest HIV prevention trial ever carried out."

PopART took place from 2013 to 2018 in 21 communities in Zambia and South Africa. It was a three-armed study (with two intervention arms and one control arm) and there were seven communities in each arm.

Arm A was the full PopART intervention. This included door-to-door services, such as testing, linkage to care for those who tested positive, and a suite of prevention services, such as condom promotion and sexually transmitted infection screening, along with immediate access to antiretroviral therapy. Arm B was the same intervention, except that treatment was offered according to national guidelines. Arm C was standard of care, with local HIV treatment and prevention services, and treatment according to national guidelines.

The researchers examined a random sampling of this population of around 48,000 adults ages 18-44. Participants were visited once at the start of the trial, then once a year for 3 years for data collection and HIV testing. Baseline HIV prevalence was similar across arms, at around 20% each, the team reported. Overall, there were 533 incident HIV infections in the cohort.

At the presentation, Hayes admitted that Arm A, which did not have a statistically significant difference in HIV infection rates, was where researchers "expected to see the greatest effect." He added that "clearly we need to do more analysis to try and explain this finding."

When asked at the press conference about why there may have been so little difference, Hayes said that by the end of the study period, "the two interventions were very similar because of the way local guidelines had evolved, and that could be why we didn't see an effect in Arm A." Hayes also noted that there also may have been a difference in sexual risk behavior between the two arms, which could explain some of the findings.

But overall, Hayes emphasized the positive results of the intervention itself. Indeed, the two intervention arms of this three-arm trial achieved the Joint United Nations Programme on HIV/AIDS (UNAIDS) after three annual rounds, and rates of viral suppression (defined as viral load <400 copies/ml) around 70%, the researchers said.

"Overall, evidence for the effect of the intervention was strong, and that's the important take-home message," Hayes said. "Taken together with findings of other studies, our results provide key evidence that a universal test-and-treat strategy can bring down the incidence of new HIV infections, even in settings with severe HIV epidemics."