May 12, 2011 (WASHINGTON) – Study results released today show significant prevention and added health benefits of starting HIV infected patients on immediate treatment.


HPTN 052, a study sponsored by the National Institute of Allergy and Infectious Diseases (NIAID) at the National Institutes of Health (NIH), found that HIV-infected men and women with relatively healthy immune systems who received immediate oral antiretroviral therapy (ART) were 96.3 percent less likely to pass on the infection to their uninfected partners and remained healthier than those whose treatment was delayed.


Though set to run until 2015, the Phase-3 clinical trial was halted early by an independent data safety monitoring board after finding unequivocally that the use of ART by relatively healthy, HIV-infected patients provided substantial protection to their partners from acquiring the virus. Although the prevention benefits of treatment have long been surmised, this represents the first large-scale, randomized controlled trial—the gold standard in medicine—showing that ART can reduce the risk of sexual transmission of HIV. The study’s Principal Investigator Myron Cohen, MD, is a member of the Center for Global Health Policy’s Scientific Advisory Committee, an Infectious Diseases Society of America fellow, and a member of the HIV Medicine Association (HIVMA).


The study enrolled 1,763 “discordant” couples—one partner is HIV-infected and the other is not—starting in 2007 at 13 study sites in nine countries, including Botswana, Brazil, India, Kenya, Malawi, South Africa, Thailand, the United States and Zimbabwe. HIV-infected participants were determined to be relatively healthy by a CD4 cell count between 350 and 550 cells/mm3 and the absence of any AIDS-related events such as Pneumocystis pneumonia within 60 days of entering the study. The HIV-uninfected partners all tested negative for the virus within 14 days of entering the study. All participants were at least 18 years of age and the median age was 33 years at the time of enrollment, 52 percent of the participants were male, 97 percent of the couples were heterosexual, and the couples agreed to participate in the trial for five years.


The couples were then placed into one of two study groups: 886 were randomly assigned to the “immediate” arm where the HIV-infected partners began receiving a three-drug HIV treatment combination; and the remaining 877 were assigned to the “deferred” arm where the HIV-infected partners received ART only after their CD4 count dropped below 250 cells/mm3 or an AIDS-related event occurred. Both groups received regular HIV testing, safe-sex counseling, free condoms, testing and treatment for sexually transmitted infections, and treatment for any HIV-related complications.


The study retained 90 percent of the participants, with only one case of HIV infection occurring among the couples assigned to receive immediate treatment compared to 27 cases of HIV infection among those who delayed treatment. Seventeen cases of previously undiagnosed extrapulmonary tuberculosis also occurred among the HIV-infected partner in the deferred treatment arm, with only three cases occurring in the immediate arm.


In the United States about half of those living with HIV who know their status and are in need of ART are receiving it, and a third of people diagnosed with HIV are not in ongoing care. An estimated 21 percent of people living with HIV remain undiagnosed, and the average CD4 count at diagnosis has been reported as 317 cells/mm3—well below the standard of care in the U.S. that calls for initiating treatment when the CD4 count is between 350 and 500 cells/mm3.


“With these results we should redouble our efforts to diagnose individuals with HIV earlier,” said HIV Medicine Association Chair Kathleen Squires, MD. “The U.S. federal treatment guidelines were modified recently to recommend earlier treatment for people with HIV infection to improve health outcomes for this patient population. We now have further evidence that effective treatment not only benefits the individual but also will help reduce the spread of this disease.”


According to the World Health Organization (WHO), only 35 percent of people in developing countries who meet the WHO eligibility requirements for treatment (CD4 count less than 350 cells/mm3, a standard lower than the level utilized in the immediate treatment arm) are receiving treatment.


“Confirmation of the protective effect of treatment on HIV transmission to sexual partners is a giant step forward in confronting the HIV epidemic,” said Center Scientific Advisory Committee Member Wafaa El-Sadr, MD, MPH. “The finding of a protective effect of HIV treatment on the development of extrapulmonary tuberculosis may play an important role in avoiding this deadly complication in HIV-infected individuals.” Tuberculosis is the number one killer of people living with HIV globally.


Antiretroviral therapy will be offered to the HIV-infected persons in the delayed treatment arm and study participants will be followed for at least one year.


For more information or to schedule an interview with one of our physician-scientist experts, contact Meredith Mazzotta at 703-740-4954 or


The HIV Medicine Association (HIVMA) is the professional home for more than 3,800 physicians, scientists and other health care professionals dedicated to the field of HIV/AIDS. Nested within the Infectious Diseases Society of America (IDSA), HIVMA promotes quality in HIV care and advocates policies that ensure a comprehensive and humane response to the AIDS pandemic informed by science and social justice. For more information, visit


The Center for Global Health Policy, established by the Infectious Diseases Society of America’s Education & Research Foundation in 2008, supports and promotes U.S. efforts to combat HIV/AIDS and tuberculosis around the world. The Center provides scientific and policy information to U.S. policymakers, federal agencies, nongovernmental organizations and the news media, linking decision-makers to the latest evidence-based input and guidance from physician/scientists and other professionals from both developing and developed countries. For more information visit



Meredith Mazzotta

Senior Communications Specialist

703-740-4954 (office)

571-216-9942 (cell)