A team of researchers led by Oregon Health & Science University has received more than $6.7 million from the National Institutes of Health to investigate how cannabis use during pregnancy may affect pregnancy outcomes for pregnant people with HIV.
The five-year grant from the NIH's National Institute on Drug Abuse will support research led by Jamie Lo, M.D., M.C.R., associate professor of obstetrics and gynecology (maternal-fetal medicine) in the OHSU School of Medicine and the Division of Reproductive and Developmental Sciences at the Oregon National Primate Research Center, and Benjamin Burwitz, Ph.D., associate professor in the Division of Pathobiology and Immunology at ONPRC. The project includes co-lead principal investigator, Jennifer Manuzak, Ph.D., of the Tulane National Primate Research Center, and other OHSU co-investigators, Matthias Schabel, Ph.D., and James Frank, Ph.D.
The study will use a nonhuman primate model to examine how daily prenatal exposure to THC — the psychoactive compound in cannabis — affects immune function, viral control, placental development and fetal outcomes in the setting of HIV-like infection and antiretroviral therapy. The research combines the expertise of the Lo lab, which studies effects of substance use on reproductive health, pregnancy and offspring outcomes, with that of the Burwitz lab, which studies infectious disease immunology, with a focus on non-human primate models.
"This project really brings together Ben's infectious disease expertise and my work on cannabis and pregnancy," Lo said. "A lot of people with HIV use cannabis for different reasons — for their symptoms and side effects of treatment. But there's been almost no research on how HIV and cannabis combined can impact maternal, placental and fetal outcomes in pregnancy."
A growing concern
According to the World Health Organization, there were 1.2 million pregnant individuals with HIV in 2023. People with HIV face higher risks during pregnancy, like premature birth and placenta problems, even when they take effective medications such as antiretroviral therapy. These risks are linked to ongoing inflammation in the body, which can also affect how babies grow.
At the same time, cannabis use is increasing among pregnant individuals, including those with HIV. While cannabis is often seen as safe because it is widely available and safety data is limited, it has been independently linked to pregnancy problems.
"HIV infection drives systemic inflammation, even when the virus is well controlled with medication," Burwitz said. "THC, the active part of cannabis, has some anti-inflammatory effects in certain settings. However, our group's prior research has shown that THC can be harmful during pregnancy. So, the big question is, does cannabis make the effects of HIV worse for the baby, or could its selective anti-inflammatory properties help? We don't know yet."
Innovative model, comprehensive approach
Using a rhesus macaque model, the OHSU team will study pregnant nonhuman primates that are infected with SIV, a virus in nonhuman primates similar to HIV; treated with antiretroviral therapy; and given a THC daily edible.
They will track how this affects the mothers' immune system, the placenta's ability to function and develop, and how the babies grow and develop. Advanced imaging and serial assessments throughout pregnancy will give researchers a detailed picture of what's happening inside the mother's body, including the placenta and fetus — something that isn't possible to do safely in pregnant individuals.
"The placenta and fetus develop in similar ways in nonhuman primates and humans," Lo said. "Also, the cannabinoid receptors — where THC binds to — of humans and nonhuman primates share the same structure. That makes this the best model for studying cannabis during pregnancy."
The team will also build a sample bank to help other scientists explore related questions in the future.
"This is the first time anyone has looked this deeply at how cannabis, HIV and pregnancy interact," Burwitz said. "Our goal is to help clinicians make better decisions and give clearer advice to pregnant individuals with HIV who may be using cannabis."
The research is supported by the National Institute on Drug Abuse of the National Institutes of Health, under award number 1R01DA064125. The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH.
All research involving animal subjects at OHSU must be reviewed and approved by the university's Institutional Animal Care and Use Committee (IACUC). The IACUC's priority is to ensure the health and safety of animal research subjects. The IACUC also reviews procedures to ensure the health and safety of the people who work with the animals. The IACUC conducts a rigorous review of all animal research proposals to ensure they demonstrate scientific value and justify the use of live animals.
