The Truth About CBD and Liver Functions

Since about 2010-2011, it’s been believed that CBD may/could cause liver damage, an understanding that has now been set on its ear with the more recent findings released by Validcare March 22, 2021, that found no adverse affects on the liver related to hemp-derived CBD intake. Validcare is an independent research company founded in 2007 that endeavored last year to study liver toxicity associated with CBD use. Working with CBD industry leaders in order to provide the Food and Drug Administration with real-world data (RWD) and real-world evidence (RWE) as had been requested by the FDA following the passage of the 2018 Farm Bill and a subsequent report to Congress in which the FDA requested this type of research be undertaken, Validcare began its study in September 2020.

Preliminary findings showed “no liver disease in the 839 participants and no increase in the prevalence of elevated liver function tests when compared to a population with a similar incidence of medical conditions,” according to a release issuedby Validcare March 23, 2020. This original understanding regarding CBD’s adverse effect on the liver grew from a study conducted at the University of Arkansas in 2019, in which a group of 8-week old mice were given what would be considered exceedingly high dosages of cannabidiol (CBD).

Overall, the mice tolerated the CBD quite well. However, among those given the human equivalent of 200 mg per kilogram of body weight, researchers found evidence of liver toxicity. Researchers also found that giving the mice the human equivalent of 50 mg of CBD - more within a realistic human dosing range, also showed signs of liver swelling and damage. The average human CBD dose typically falls within a range of .05 mg/kg to .20 mg/kg per day, meaning it is far below the threshold used in the study that yielded potentially adverse effects.

The FDA began the conversation of wanting to work with hemp-industry stakeholders to gain RWD and RWE, so they could determine the path forward in regulatory measures that are needed, based on actual data. FDA Commissioner of Food and Drug Stephan M. Hahn, M.D. and Deputy Commissioner Amy Abernathy, M.D., PhD., said in part in a release at FDA.gov, “We see an important public health opportunity in using novel sources of data and rigorous analytical methods to build a more robust base of scientific evidence on the safety profile and use of CBD products. The FDA is uniquely situated to contribute its expertise in evaluating data from different sources to inform regulatory decision-making. We think that  real-world data  (RWD) on CBD use and safety has a crucial role alongside data from other types of studies to fill in the current gaps in our understanding.”

They proceed to lay out specific steps within specific categories the FDA is committed to taking in order to determine effective regulation of hemp-derived CBD. In part, Valident’s press release stated,“Our primary endpoint in this study is to observe potential liver effects in adults ingesting oral forms of hemp derived CBD for a minimum of 60 days. What we observed to date is no clinical evidence of liver disease in any participants. We observed slight, clinically insignificant elevations of liver function tests in less than ten percent of consumers irrespective of age, product composition and form and the amount consumed. Three of the 839 participants had 3x normal levels of the liver enzyme ALT. These three consumers are taking prescription medications that are known to elevate liver enzymes, and we are investigating whether prescribed medications or other factors contribute to these outliers,” said co-investigator Jeff Lombardo PharmD, BCOP. The study’s investigators were surprised to find almost 70% of study participants reported having a medical condition and taking medications for those conditions, without an increase in reporting of adverse events. Studies of similar populations demonstrate an 11% elevation in liver function tests, while this research demonstrated ~9% elevation1. “This unexpected, positive finding makes the data even more compelling and provides significant data to consider secondary safety measurements in the general population,” said Keith Aqua, MD, co-principal investigator of this IRB-approved study.

“We are encouraged by these findings and hopeful this study provides FDA with sufficient science-based data to determine and take action on a safe regulatory path forward,” said Dr. Aqua. “We will continue to analyze these real world data and are adding a second cohort to this study to increase statistical certainty for liver safety and secondary measures across diverse populations and consumers with various medical conditions.”

For full text from the FDA, visit www.fda.gov/news-events/fda-voices/better-data-better-understanding-use-and-safety-profile-cannabidiol-cbd-products .

For full text from Validcare, visit https://validcare.com/press/validcares-clinical-study-reports-preliminary-results-of-cbd-liver-safety/