Science Breakthroughs

As announced in this issue,Science 's choice for Breakthrough of the Year for 2011 is based on the paperPrevention of HIV-1 Infection with Early Antiretroviral Therapy * (see p. 1628). This provocative choice was made after much deliberation involving our News and Editorial staff, plus our Board of Reviewing Editors. The study involved more than 1700 heterosexual couples, of whom one partner was infected with the human immunodeficiency virus (HIV) and the other was not at the start of the trial. All those infected still had relatively intact immune systems. The study gave antiretroviral drugs to half of the infected people and delayed giving treatment to the other half until their immune systems declined to a dangerous degree. The results of this early treatment with a cocktail of antiviral drugs were dramatic, lowering the rate at which the HIV-free partner became infected 20-fold, while also improving outcomes for the infected partner. In combination with other promising clinical trials, the results have galvanized efforts to end the world's AIDS epidemic in a way that would have been inconceivable even a year ago. “The goal of an AIDS-free generation is ambitious, but it is possible,” U.S. Secretary of State Hillary Clinton told scientists last month.