An in silico study by Indian researchers affiliated with Deen Dayal Upadhyaya Gorakhpur University and the University of Lucknow of 18 extracted compounds of 11 different species of herbal plants common to India has found that cannabidiol (CBD) has the potential to inhibit COVID 19 protease (an enzyme that breaks down proteins and peptides).
Using molecular docking analysis, the interaction mechanism between ligands and COVID 19 receptors were analyzed to determine the binding affinity (expressed in kilocalories/mole), FF score (greater negative FF score suggests a more favorable binding mode), absorption (Log P score), & aqueous solubility (Log S score).
The analysis of cannabidiol determined a likely binding affinity of -7.10 (indicating that cannabidiol would likely bind to the COVID 19 protease) and an FF score of -1214 (indicating a likely good fit with COVID 19 protease). However, the analysis also determined that the Log P & S values of cannabidiol indicated that the compound has high hydrophobicity, poor absorption, and low aqueous solubility, indicating lower bioavailability than most of the compounds in the analysis set.
This analysis is not a human clinical trial and cannot be used to make conclusions; however, it suggests that cannabidiol may have some utility in inhibiting COVID 19. The low bioavailability of cannabidiol may be increased by the application of nanotechnology techniques that increase aqueous solubility and absorption.