|Attending the 25th anniversary commemoration of the NIH Multicenter AIDS Cohort Study are (from l) Dr. Alvaro Muñoz, former principal investigator of the MACS data coordinating center; Dr. Charles R. Rinaldo, PI of the MACS Pittsburgh site; Dr. Carl Dieffenbach, director of the NIAID Division of AIDS; Dr. Lisa P. Jacobson, PI of the data coordinating center; Dr. John Phair, PI of the MACS Chicago site; Dr. Joseph Margolick, PI of the MACS Baltimore site; and Dr. Roger Detels, PI of the MACS Los Angeles site.
The 25th anniversary of one of the longest U.S. studies of people with HIV/AIDS was marked on May 12 at the Carnegie Institution for Science in Washington, D.C. The NIH Multicenter AIDS Cohort Study (MACS) has contributed significantly to the scientific understanding of HIV, AIDS and the effects of antiretroviral therapy through more than 1,100 publications, many of which have guided public health policy and the clinical care of people with HIV.
MACS investigators prospectively study the natural history of HIV infection, treated and untreated, in thousands of homosexual and bisexual men at sites in Baltimore, Chicago, Pittsburgh and Los Angeles. The National Institute of Allergy and Infectious Diseases and the National Cancer Institute developed MACS and have been its principal sponsors.
“When we were preparing to start this study in early 1984, we didn’t even know what the cause of AIDS was,” recalls Dr. John Phair, the study chair and principal investigator of the Chicago site at Northwestern University. But soon after, in May 1984, the laboratory of Dr. Robert Gallo of NCI published four papers in Science confirming that the retrovirus then known as LAV or HTLV-III caused the terrifying new disease called AIDS.
When the first diagnostic test for HIV became available in 1985, MACS investigators learned that 40 percent of their participants were infected with the virus. “That gave us an enormous advantage,” Phair explains, “because we had the ability to study men who became infected with HIV during the investigation, and also to study the natural history of established HIV infection.”
The MACS has cumulatively enrolled nearly 7,000 men who have sex with men. Participants visit their study sites every 6 months to donate biological specimens and answer lengthy questionnaires on medical history and behaviors, every man adding 8,500 new pieces of information to the investigation during each visit. Today, 2,525 men participate in the study; the others have dropped out or died, usually from AIDS.
“The participants’ loyalty to the study and the scientific knowledge we have gained from them have greatly benefited the health of HIV-infected people worldwide,” notes Dr. Lisa Jacobson, principal investigator of the MACS data coordinating center at Johns Hopkins University.
The longstanding record of fruitful research by MACS at relatively low cost to NIH has led NIAID director Dr. Anthony Fauci to describe the study as a gift that keeps on giving.