Cohen, Myron S.Chen, Ying Q.McCauley, MarybethGamble, TheresaHosseinipour, Mina C.Kumarasamy, NagalingeswaranHakim, James G.Kumwenda, JohnstoneGrinsztejn, BeatrizPilotto, Jose H.S.Godbole, Sheela V.Mehendale, SanjayChariyalertsak, SuwatSantos, Breno R.Mayer, KennethHoffman, Irving F.Eshleman, Susan H.Piwowar-Manning, EstelleWang, LeiMakhema, JosephMills, Lisa A.de Bruyn, GuySanne, IanEron, JosephGallant, JoelHavlir, DianeSwindells, SusanRibaudo, HeatherElharrar, VanessaBurns, DavidTaha, Taha E.Nielsen-Saines, KarinCelentano, DavidEssex, MyronFleming, Thomas R.2016-04-202011Cohen, Myron S., Ying Q. Chen, Marybeth McCauley, Theresa Gamble, Mina C. Hosseinipour, Nagalingeswaran Kumarasamy, James G. Hakim, et al. 2011. “Prevention of HIV-1 Infection with Early Antiretroviral Therapy.” N Engl J Med 365 (6) (August 11): 493–505. doi:10.1056/nejmoa1105243.0028-4793http://nrs.harvard.edu/urn-3:HUL.InstRepos:26667502BACKGROUND: Antiretroviral therapy that reduces viral replication could limit the transmission of human immunodeficiency virus type 1 (HIV-1) in serodiscordant couples. METHODS: In nine countries, we enrolled 1763 couples in which one partner was HIV-1-positive and the other was HIV-1-negative; 54% of the subjects were from Africa, and 50% of infected partners were men. HIV-1-infected subjects with CD4 counts between 350 and 550 cells per cubic millimeter were randomly assigned in a 1:1 ratio to receive antiretroviral therapy either immediately (early therapy) or after a decline in the CD4 count or the onset of HIV-1-related symptoms (delayed therapy). The primary prevention end point was linked HIV-1 transmission in HIV-1-negative partners. The primary clinical end point was the earliest occurrence of pulmonary tuberculosis, severe bacterial infection, a World Health Organization stage 4 event, or death. RESULTS: As of February 21, 2011, a total of 39 HIV-1 transmissions were observed (incidence rate, 1.2 per 100 person-years; 95% confidence interval [CI], 0.9 to 1.7); of these, 28 were virologically linked to the infected partner (incidence rate, 0.9 per 100 person-years, 95% CI, 0.6 to 1.3). Of the 28 linked transmissions, only 1 occurred in the early-therapy group (hazard ratio, 0.04; 95% CI, 0.01 to 0.27; P<0.001). Subjects receiving early therapy had fewer treatment end points (hazard ratio, 0.59; 95% CI, 0.40 to 0.88; P=0.01). CONCLUSIONS: The early initiation of antiretroviral therapy reduced rates of sexual transmission of HIV-1 and clinical events, indicating both personal and public health benefits from such therapy.en-USJournal Article2016-04-2010.1056/NEJMoa1105243