By Brenda L. Mooney

BETHESDA, MD—When it comes to treating acute HIV infection, sooner is better, noted a new study led by U.S. military researchers.

The study, published in the Journal of the International AIDS Society, compared viral load in patients during acute HIV infection. The researchers, led by the U.S. Military HIV Research Program (MHRP), determined that those who began antiretroviral therapy (ART) immediately had significantly lower viral loads vs. those for whom therapy was delayed.1

The study team said it embarked on the review because, while the extent of viral replication during acute HIV infection (AHI) influences HIV disease progression, how ART affects viral load during AHI has not been fully explored.

This analysis reviewed viral load data obtained during the first year of HIV infection from two MHRP-led cohort studies in Thailand: the RV217 study and the RV254 study.

The first study, RV217, involved a prospective cohort of individuals at high risk for HIV who are regularly screened for AHI. The authors pointed outthat ART is initiated according to standard of care at local health centers, and none in the analysis had begun ART.

The RV254 cohort, meanwhile, enrolls patients diagnosed with AHI at an HIV testing center that has routine AHI screening, and those are offered immediate ART.

Results indicated that HIV replication is halted soon after ART initiation, resulting in a stark difference in viral load trajectories between the treated and untreated volunteers. The study pointed out that by day 12 of the study—four days after ART began in RV254 volunteers—the untreated group had a 2.7-fold higher viral load level compared to those treated.

Those increases burgeoned to 135-fold by day 30 and 1148-fold by day 120.

Predicted log viral load kinetics comparing RV217-untreated vs. RV254-treated acute HIV infection participants.The predicted values with a 95% confidence band are shown. The green and purple lines represent the upper and lower bounds of the 95% confidence intervals. The grey vertical line indicates the median start of treatment for RV254. Predicted log viral load means (95% confidence interval) for each study is given as follows: day 5 – RV217: 5.23 (4.87, 5.6), RV254: 5.21 (4.95, 5.48); day 10 – RV217: 6.14 (5.75, 6.54), RV254: 5.92 (5.78, 6.06); day 12 – RV217: 6.19 (5.78, 6.59), RV254: 5.76 (5.62, 5.9); day 30 – RV217: 4.89 (4.64, 5.14), RV254: 2.76 (2.64, 2.88); day 120 – RV217: 4.68 (4.48, 4.87), RV254: 1.62 (1.58, 1.67).

“Initiating ART in AHI dramatically changed the trajectory of viral load very early in the course of infection, which could have implications for reducing potential to transmit HIV and enhancing responses to future HIV remission strategies,” explained Jintanat Ananworanich, MD, PhD, MHRP’s Associate director for Therapeutics Research and protocol chair of RV254.

Background information in the articles explained that inhibiting viral replication infection prevents viral mutation, and reduces immune destruction, seeding of the latent HIV reservoir and immune activation.

“Initiating ART in AHI dramatically changed the trajectory of VL very early in the course of infection that could have implications for reducing transmission potential and enhancing responses to future HIV remission strategies,” the study concluded.

“There is an urgency to initiate ART when acute infection is identified,” added senior author Merlin Robb, MD. MHRP’s Clinical Deputy Director and senior author of the paper. “New and inexpensive strategies to engage and test individuals at high risk for HIV as well as immediate treatment access will be needed to improve the treatment of acute infection globally.”

  1. Ananworanich J, Eller LA, Pinyakorn S, Kroon E, Sriplenchan S, Fletcher JL, Suttichom D, Bryant C, Trichavaroj R, Dawson P, Michael N, Phanuphak N, Robb ML. Viral kinetics in untreated versus treated acute HIV infection in prospective cohort studies in Thailand. J Int AIDS Soc. 2017 Jun 26;20(1):1-7. doi: 10.7448/IAS.20.1.21652. PubMed PMID: 28691436.