Early ART reduces risk for HIV-1 transmission among serodiscordant couples
Early ART initiation was associated with a 93% lower risk for HIV-1 transmission among serodiscordant couples from nine different countries, according to data from the HIV Prevention Trials Network 052 trial.
“The global HIV-1 epidemic is primarily driven by sexual transmission. Potent, durable HIV-1 prevention strategies are required to reduce the risk of viral transmission from infected persons to their sexual partners,” Myron S. Cohen, MD, chief of the division of infectious diseases at the University of North Carolina, and colleagues wrote.
Researchers enrolled 1,763 serodiscordant couples in Botswana, Brazil, India, Kenya, Malawi, South Africa, Thailand, the United States and Zimbabwe with enrollment running from June 2007 through May 2010. Participants reported no previous ART, except for those who had used it for short periods to prevent mother-to-child transmission, and had CD4+ counts of 350 to 550 cells/mm3.
The couples were randomly assigned to one of two groups: ART at enrollment (n = 886), and ART after two consecutive CD4+ counts below 250 cells/mm3 or the development of an “AIDS-defining illness” (n = 877). Participants had monthly follow-ups for 3 months, followed by quarterly visits for the study duration.
Partners in the early ART group had a 93% lower risk for genetically linked HIV-1 infection than those in the delayed ART group (HR = 0.07; 95% CI, 0.02-0.22). Researchers observed 78 HIV-1 infections during the study (annual incidence, 0.9%; 95% CI, 0.7-1.1). Of the 72 infections for which researchers determined viral-linkage status, 46 were linked, including 43 in the delayed ART group (incidence, 0.5%; 95% CI, 0.4-0.7). Twenty-six were unlinked, with 14 in the early ART group and 12 in the delayed group (incidence, 0.3%; 95% CI, 0.2-0.4).
“The final results of the HPTN 052 study show that successful treatment of HIV-1 is a highly effective tool for the prevention of sexual transmission of the virus,” Cohen and colleagues wrote. “These findings support the results of observational studies and controlled clinical trials showing the personal and public health benefits of the earliest possible initiation of HIV-1 treatment.” – by Andy Polhamus
Disclosure: Cohen reports other support from Janssen Global Services, Medscape, Merck Research Laboratories and Roche Molecular Systems outside the submitted work. Please see the full study for a list of other authors’ relevant financial disclosures.