An interdisciplinary team of researchers from the University of Chicago has found evidence that cannabidiol, or CBD, can inhibit infection by the COVID-19 virus in human cells and in mice. They caution, however, that the COVID-blocking effects of CBD come only from a high-purity, specially formulated dose taken in specific situations. The study’s findings do not suggest that consuming commercially available products with CBD additives that vary in potency and quality can prevent COVID-19, reported UChicago News.
The study, published on Jan. 20 in Science Advances, found CBD showed a significant negative association with positive COVID tests in a national sample of medical records of patients taking the FDA-approved drug for treating epilepsy.
Now clinical trials should be conducted to determine whether CBD could eventually be used as a preventative or early treatment for COVID-19.
“CBD has anti-inflammatory effects, so we thought that maybe it would stop the second phase of COVID infection involving the immune system, the so-called ‘cytokine storm,’” said Marsha Rosner, Charles B. Huggins professor in the Ben May Department of Cancer Research and a senior author of the study. “Surprisingly, it directly inhibited viral replication in lung cells.”
Researchers first treated human lung cells with CBD for two hours before exposing the cells to the COVID virus and monitoring them for the virus and the viral spike protein. They found that, above a certain threshold concentration, CBD inhibited the virus’ ability to replicate. Further investigation found that CBD had the same effect in two other types of cells and for three variants of the COVID virus in addition to the original strain.
“A clinical trial is necessary to determine whether CBD is really effective at preventing or suppressing SARS-CoV-2 infection,” said Rosner. The research team emphasized that the COVID-blocking effects of CBD were confined strictly to high purity, high concentrations of CBD. Closely related cannabinoids did not have the same effect and combining CBD with equal amounts of THC actually reduced the efficacy of CBD.
“We caution against the use of non-medical formulations including edibles, inhalants, or topicals as a preventative or treatment therapy at the present time,” added the researchers.
Photo by Fusion Medical Animation on Unsplash.
