Improving HIV/AIDS treatment and prevention through statistical expertise
December 2, 2024—Over four decades, advancements in science and public health have turned HIV from a probable death sentence into a manageable chronic condition and have reduced AIDS-related deaths by 69% from their peak in 2004. Many of these advancements were fueled by the work of researchers at Harvard T.H. Chan School of Public Health’s Center for Biostatistics in AIDS Research (CBAR). Based in the School’s Department of Biostatistics, CBAR biostatisticians and epidemiologists have helped conduct and promote quality HIV/AIDS research since 1995, in pursuit of a world free of the disease.
In honor of World AIDS Day on Dec. 1, Michael Hughes, professor of biostatistics and director of CBAR, shared some thoughts on the CBAR’s past accomplishments, current research, and ongoing impact.
Q: What role does CBAR play in HIV/AIDS research?
A: CBAR provides leadership and expertise in designing and analyzing the results of clinical trials and observational studies around new treatments and vaccines for people living with HIV. We also undertake methodological research to help improve the designs and data analyses of these studies. Our studies focus on the whole lifespan—pregnant people, babies, children, adolescents, and adults of all ages.
We also contribute our statistical expertise to research around the prevention and treatment of other diseases that are more common in people living with HIV, such as tuberculosis, hepatitis B and C, and heart and liver diseases. And our expertise in infectious disease clinical trials is widely recognized such that during the COVID-19 pandemic we helped with a large clinical study evaluating possible treatments for the virus. We’re currently doing the same for possible treatments for mpox.
Many of CBAR’s faculty members, research associates and scientists, statisticians, and epidemiologists have worked with the Center for decades, reflecting their substantive engagement in HIV/AIDS research over the course of the HIV/AIDS pandemic.
Q: What notable advancements in HIV/AIDS research has CBAR had a hand in?
A: Since the late 1980s, the research we have been involved in has contributed significantly to the approval of drugs for the treatment and prevention of HIV/AIDS and common co-infections, as well as to U.S. and World Health Organization guidelines for treating and preventing HIV infection. We’ve been involved in well over a thousand clinical trials, observational studies, and laboratory studies of disease and treatment mechanisms. I’ll highlight three, from the 1990s and early 2000s, that helped change the face of the HIV/AIDS pandemic:
- The Advancing Clinical Therapeutics Globally for HIV/AIDS and Other Infections (ACTG) network’s clinical trial that showed that antiviral drugs can be used during pregnancy, labor, and delivery to help prevent transmission of HIV from mother to baby. This study and subsequent ones also showed that if a mother’s level of HIV virus is suppressed to very low levels, the risk of transmission is extremely small.
- The Botswana Harvard Partnership’s clinical trial [led by Harvard Chan School’s Roger Shapiro] that showed that a combination of antiretroviral drugs can suppress HIV viral levels in mothers and prevent transmission to their infants during breastfeeding.
- The ACTG network’s clinical trial that showed we can use a new class of drugs—protease inhibitors—in combination with other drugs to markedly reduce the risk of HIV progressing to AIDS, thereby improving patients’ chances of survival. This was a turning point in the HIV/AIDS pandemic: We saw dramatic drops in mortality with the use of such combination therapies. It was also the beginning of the development of other treatment combinations which were increasingly more potent, easier to take, and better tolerated by patients, which turned HIV into a potentially chronic disease.
We’ve also been involved in more recent studies and breakthroughs, including ACTG network studies that have shown the efficacy of a long-acting, injectable antiretroviral therapy (critical for those who face barriers to taking daily pills); the efficacy of a daily statin to reduce the risk of major adverse cardiovascular events in people living with HIV; and the potential efficacy of a new hepatitis B vaccine for people living with HIV who do not respond to current hepatitis B vaccines.
In partnership with the International Maternal Pediatric Adolescent AIDS Clinical Trials (IMPAACT) network and the Pediatric HIV/AIDS Cohort Study (PHACS), we’ve worked on studies that have supported the licensures of treatments for HIV and other infectious diseases in children and pregnant people and evaluated protocols for safely, effectively transitioning young people living with HIV from pediatric to adult care.
Q: What research is CBAR currently focusing on?
A: We continue to collaborate on studies concerning the HIV viral reservoirs that persist in some people, even if they’re on highly effective treatments. We want to understand why these high levels of virus persist, and if antibody treatments could be effective. This area of research is among our most challenging, but also one of our most exciting: Its goal is to produce a functional cure for HIV infection that would allow people to remain in remission for extended periods without the need for treatment.
Q: How does CBAR incorporate training into its work?
A: We are deeply involved in supporting early career investigators in the ACTG, IMPAACT, and PHACS networks. Just recently, we had an IMPAACT early career investigator from South Africa visiting CBAR to collaborate with biostatisticians here on a project related to a potential tuberculosis biomarker in pregnant people living with HIV. I also have a National Institutes of Health training grant which supports nine PhD students and a postdoc in biostatistics and epidemiology methods research related to HIV.
Q: What motivates CBAR to continue helping make more advancements in HIV/AIDS research?
A: Despite the fact that HIV infection has changed from an acutely life-threatening disease to more of a chronic disease, it’s critically important to remember the ongoing global impact of the HIV pandemic: There are some 40 million people living with HIV, and well over a million adults and children still acquiring HIV annually. Our work collaborating with an impressive array of investigators around the world remains critically important for finding new treatment options that both improve the health of people living with HIV and minimize the risk of transmission of HIV.
Illustration: iStock/Red Diamond; Photo: courtesy of Michael Hughes
