A new study found how experts are better able to predict how quickly the human immunodeficiency virus (HIV) will return after a patient stops receiving treatment.
Published in the journal Nature Communications, the research discovered that while current antiretroviral therapy (ART) stops the virus’ replication, it does not totally remove it. This keeps the complete destruction of the virus one of the “holy grails” of research.
This development results from a decade-long collaboration between scientists from the University of New South Wales (UNSW) and Oxford University, and probes why HIV infection continues in some patients but stays dormant and barely detectable in the rest.
The team led by Oxford scientist John Frater analyzed data from a randomized trial of patients involved in the SPARTAC (Short Pulse Anti-Retroviral Therapy at Seroconversion) study. It compared the T-cells – active agents in protecting the immune system – of 154 patients from Europe, Brazil and Australia who had their ART stopped after 12 or 48 weeks.
Researchers identified PD-1, Tim-3 and Lag-3 from 18 immune system biomarkers as “statistically significant predictors” of when the virus would rebound. High levels of these biomarkers, “attached to ‘exhausted’ T-cells” before patients started ART, were linked to earlier relapse once treatment was interrupted.
“The SPARTAC study will never be able to be replicated again,” said Professor Rodney Phillips, UNSW dean of medicine, saying the study offers a rare chance to investigate the persistence of the virus.
Running from 2003 to 2011 in eight countries, SPARTAC is the largest randomized controlled trial ever conducted in primary HIV infection.
According to study co-author Professor Anthony Kelleher of the Kirby Institute at UNSW, it is essential to understand the remission of the human immunodeficiency virus in eradicating the disease, enabling experts to predict its behavior before taking patients off ART to test other therapies.
Patients are now recommended to continue on ART mostly as initiated by START (Strategic Timing of Antiretroviral Treatment), a separate endeavor of the Kirby Institute. The results reflected the benefits of starting ART early.
Biomarkers, added the research team, should be considered in the further research of post-ART HIV management.