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April 26, 2004

Nation’s Largest AIDS Study Marks 20th Anniversary

The nation’s largest and longest ongoing study of HIV infection is marking its twentieth anniversary. The Multicenter AIDS Cohort Study (MACS) is an ongoing prospective study of the natural and treated histories of infection with human immunodeficiency virus (HIV-1) in homosexual and bisexual men. It is conducted at sites in Baltimore, Chicago, Pittsburgh and Los Angeles and was established in April 1984. The Study to Help the AIDS Research Effort (SHARE) is the name of the Baltimore MACS site, which includes men from Baltimore, Md., and Washington, DC, and is based at the Johns Hopkins Bloomberg School of Public Health.

Joseph B. Margolick, MD, PhDJoseph B. Margolick, MD, PhD, lead investigator, said, “SHARE and MACS have made major contributions to our understanding of the mechanisms of HIV disease and how to use the increasingly effective treatments that have become available since this study began. By participating in this study for up to 20 years in many cases, the men in SHARE have shown a dedication to the fight against AIDS that is a model for every effort to improve human health and dignity. We all owe them a tremendous debt of gratitude.”

Christopher Camp, SHARE’s Community Advisory Board chair for the past 16 years, said, “Throughout the years, the study has become one of the primary support networks for those of us living with HIV/AIDS. One of the most amazing things about the study is that long after study participants have passed away, they continue to make significant contributions to the study due to their blood specimens in the repository. That’s incredible.”

At its beginning, the four MACS sites investigated the natural history of a new infection that came to be known as HIV/AIDS. To date, more than 6,900 men have volunteered to visit one of the sites twice a year to be tested and to donate specimens for studies. Over 900 journal articles have been published from the data collected from the MACS. The study contributed to the development of treatment guidelines for HIV infection and other infections associated with it; defined the occurrence and mechanisms of HIV-associated dementia; identified genes that influence HIV disease progression; standardized lab procedures of HIV research; and assisted in understanding how HIV is spread.

SHARE’s current goals are to characterize the range of responses to Highly Active Antiretroviral Therapy (HAART), with special emphasis on the disease stage at which HAART is taken, to define the effect of HAART and infections other than HIV on clinical outcomes of HIV infection and to characterize the long-term adverse effects of HAART. In addition, SHARE studies long-term patterns of HAART use and identifies patterns of behavior that can lead to the spread of HIV infection. The study has been renewed by the National Institutes of Health through 2009.

To learn more about SHARE, visit or call 410-955-7090, 866-392-8991 or 202-745-6137.

Public Affairs media contacts for the Johns Hopkins Bloomberg School of Public Health: Kenna Brigham or Tim Parsons at 410-955-6878 or Photographs of Joseph Margolick are available upon request.