A combination of compounds found in cannabis showed the potential to treat or even prevent coronavirus infections in human lung cells, according to recently published research. The study, “In Vitro Evaluation of the Activity of Terpenes and Cannabidiol against Human Coronavirus E229,” was published by the peer-reviewed journal Life on March 29.
The research studied the antiviral action of a proprietary formula of terpenes, which are natural volatile compounds found in many plants including cannabis. The formulation, known as NT-VRL, is a combination of 30 terpenes including beta-caryophyllene, eucalyptol and citral developed by cannabis technology company Eybna.
Terpenes have shown the potential to treat a wide variety of viral infections in many in vitro studies, and research released by Eybna last year found that NT-VRL combined with cannabidiol (CBD) showed promise as a treatment for the severe inflammatory response seen in many Covid-19 patients known as a cytokine storm.
Additional research was conducted by Eybna and pre-clinical contract research organization Pharmaseed to evaluate the antiviral properties of NT-VRL with and without CBD against the human coronavirus strain HCoV-229E. Although not the strain of coronavirus that causes Covid-19 (SARS-CoV-2), the less virulent HCoV-229E is associated with various respiratory illnesses ranging from the common cold to severe pneumonia and is considered a good alternative for preliminary research.
The antiviral action of NT-VRL was determined by treating uninfected lung cells with the substances researched in the study. In addition to NT-VTRL and CBD, pyrazofurin, a natural antiviral that has shown effectiveness against SARS-related coronaviruses, was used as a positive control. Glycyrrhizin, a compound that has been used to successfully treat SARS patients, was used as a second positive control. The therapeutic activity of the compounds was evaluated in terms of the cytopathic effect observed under an inverted microscope and with an in vitro cell viability assay.
All of the compounds in the study showed varying degrees of antiviral activity. When NT-VRL and CBD were applied together, however, the two substances showed a synergistic antiviral effect that was stronger than the positive controls pyrazofurin and glycyrrhizin. The researchers reported that NT-VRL exhibited an antiviral effect and “should preferably be pre-incubated with cells prior to virus exposure.”
“These results suggest that NT-VRL with or without CBD could be useful as a preventative measure against coronaviruses,” the researchers wrote. “As the lungs are the organs most affected by COVID-19, preventative treatment directly to the lungs, possibly via inhalation, would be the ideal administration route for this potential therapeutic solution.”
Does Cannabis Use Provide Protection Against Coronavirus?
When asked in a virtual interview if the potential for NT-VRL inhalation to be used as a preventative for coronavirus infections suggests that smoking or vaping cannabis could have a similar effect, Eybna CEO and co-founder Nadav Eyal notes that it “is important to be careful to not jump to conclusions of this kind.”
But if a clinical trial of the compound as a preventative for coronavirus infections is successful, “due to the fact that NT-VRL terpenes are also found in cannabis strains, it can be estimated that cannabis evaporation will also have some effectiveness,” says Eyal.
After reviewing the study, Jahan Marcu, Ph.D., founding partner of cannabis science consulting firm Marcu & Arora and the editor-in-chief of the American Journal of Endocannabinoid Medicine, said in a phone interview that the potential for using terpenes and CBD as a treatment for coronavirus infections is an interesting idea to pursue, and agrees that people should not view their cannabis use as protection from illness.
“It’d be great if we could just sort of smoke our way out of a coronavirus, but I don’t think that this study shows that,” Marcu says, adding that further research, including into the mechanism at work and the formulation’s effect on other factors such as viral load in living organisms, is warranted.
Eybna’s next step in the development of NT-VRL is a Phase 2 clinical trial slated for the second quarter of 2021 at one of Israel’s leading hospitals to determine if the product exhibits the same benefits in Covid-19 patients. And currently, the scientific team at the company is working to clarify NT-VRL’s mechanism of action and to prove that the terpene formulation is effective against other strains of the coronavirus, as well as other types of viruses such as those that cause influenza.
“If clinically proven, NT-VRL could be the first preventative line of defense for a population with a high infection risk,” Eyal says. “It would significantly strengthen existing preventative measures such as face masks, maintaining personal hygiene and vitamin D usage.”
The authors of the study note that while the distribution of vaccines to prevent Covid-19 has begun, the timeline for vaccination on a global scale is yet to be determined. And even when widespread access to the vaccines is achieved, there will always be individuals for whom inoculation is not recommended, making preventative measures and new treatments highly beneficial.
“Several population groups, such as the youngest age groups and people with health limitations, will take longer to vaccinate,” they wrote. “Therefore, a preventative antiviral treatment to be used in conjunction with vaccines or even temporarily until vaccination or other alternatives become available would be valuable.”