Identifying People During the Acute and Early Phases of HIV

Clinical Infectious Diseases, December 2020.

Research suggests many potential benefits to starting antiretroviral therapy (ART) within the first few days or weeks after HIV has been acquired. Studies that enroll participants with early HIV or after early treatment initiation are especially important to test potential strategies to control HIV that don’t depend on lifelong ART. However, it is logistically difficult to diagnose HIV and start ART so soon after acquisition. A5354 attempted to do this at 30 ACTG sites in the Americas, Africa, and Southeast Asia. Sites used any of six criteria to identify people with very early HIV, including combinations of viral load testing, antibody testing, and antigen testing. Researchers utilized new ways of looking at how strongly positive some of these tests were (the signal-to-cutoff ratio) to determine how recently HIV was acquired. The study enrolled 195 participants and started 171 (87.7%) on ART on the day of enrollment and 24 (12.3%) the next day. After enrollment, centralized testing confirmed that 188 (96.4%) participants had acute or early HIV. Four (2.0%) participants had acquired HIV long ago and were now in the chronic phase of HIV while three (1.5%) were found not to have HIV, discontinued ART, and were withdrawn from the study. The signal-to-cutoff ratio correctly identified 99 of 122 (81.2%) participants who were in specific stages of acute or early HIV (Fiebig stages 2-4) with no false-positive results. Because some of the inclusion criteria in A5354 did not require an HIV viral load (which may take several days or more to produce a result), they may be helpful for clinicians and researchers who are trying to accurately diagnose acute or early HIV and start ART quickly.

How quickly one needs to start HIV treatment is still being investigated. There are no data demonstrating differences in clinical outcomes in starting HIV treatment on the same day of diagnosis versus the within 2-4 weeks of diagnosis.  There is broad consensus that starting therapy as soon as possible is beneficial for the individual, may prevent further transmission of HIV and waiting too long (more than 8-12 weeks) can result in illness. Some of the barriers to initiating treatment on the same day of diagnosis is ensuring that the individual is confirmed to have HIV and starting therapy that is likely to work (meaning no resistance to treatment). This study helps to begin to identify people early on with HIV and allow for more prompt initiation of treatment.

To read the full manuscript, click here.