News of the WeekHIV/AIDS Clinical Trials

A Powerful and Perplexing New HIV Prevention Tool

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Science  03 Dec 2010:
Vol. 330, Issue 6009, pp. 1298-1299
DOI: 10.1126/science.330.6009.1298

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On 2 October, two dozen AIDS researchers gathered to learn whether an HIV prevention study they had just completed would become a millstone or a milestone for the field. Unlike the many HIV prevention trials that have failed or had positive but barely significant results, the study—called the Pre-Exposure Prophylaxis Initiative—showed unequivocally that the treated group had 44% fewer infections after an average of 1.2 years. More encouraging still, most of the failures seemed to occur among those who did not take the pill as directed: A small substudy found that risk of infection plummeted by 92% in people who had measurable drug levels in their blood. The researchers applauded and some even cried when they heard the bottom line. But the good news was tempered by a dizzying array of complicated issues about human behavior, ethics, resources, risk, and public health.