Pharmaceutically Manufactured Cannabidiol Shows No Cardiac Safety Issues

Recent research presented at the Heart Failure 2025 conference indicates that a pharmaceutically manufactured cannabidiol formulation demonstrates a favorable safety profile, particularly concerning cardiac health. This is particularly significant as treatment options for inflammatory heart conditions like myocarditis and pericarditis remain limited.

Cannabidiol, which does not possess the psychotropic properties commonly associated with cannabis, has been identified as a potential inhibitor of the inflammasome pathway. This intracellular mechanism plays a crucial role in the onset and progression of myocarditis, pericarditis, and heart failure.

Dr. Leslie Cooper from the Mayo Clinic in Jacksonville, Florida, who served as a co-principal investigator for the trial, emphasized the need for the study. He pointed out that patients with cardiovascular disease (CVD) or those at risk for CVD who were hospitalized due to COVID-19 showed elevated risks for cardiac inflammation.

The trial was structured as a placebo-controlled study involving adult participants with prior histories of CVD or at least one significant risk factor. These patients had been hospitalized with non-critical cases of COVID-19.

Participants were randomly assigned to receive either a GMP-cannabidiol formulation, adjusted to a maximum of 7.5 mg/kg twice daily, or a placebo. The primary focus for safety was the incidence of serious adverse events (SAEs) and other adverse events (AEs) within 60 days post-randomization.

Due to challenges in patient recruitment amidst the pandemic, the trial was concluded prematurely. A total of 89 patients were included, with an average age of 61 years; 43% of the participants were female. Of these, 45 received GMP-cannabidiol, while 44 were given a placebo.

The overall safety outcomes were comparable between the two groups. Adverse events attributed to the treatment occurred in 24.4% of the GMP-cannabidiol recipients compared to 22.7% in the placebo group. Serious adverse events were reported in 11.1% of those on GMP-cannabidiol versus 9.1% in the placebo cohort. Notably, there were no fatalities in the GMP-cannabidiol group, while two deaths occurred in the placebo group, both attributed to respiratory failure.

In terms of common adverse events, the frequency of gastrointestinal disorders was 22.2% for GMP-cannabidiol and 20.5% for placebo. Nervous system disorders were reported at rates of 17.8% and 18.2%, respectively, while respiratory issues occurred in 11.1% of the GMP-cannabidiol group compared to 9.1% in the placebo group.

Crucially, the cardiovascular safety profile of GMP-cannabidiol was found to be similar to that of the placebo. Cardiac disorders were documented in 9% of patients in both groups. Only one participant (2%) in the GMP-cannabidiol cohort exhibited mild QTc prolongation, as identified through electrocardiogram (ECG) monitoring. Overall, ECG measurements showed minimal deviations, with average QTc intervals remaining consistent from the baseline to day 28 in both groups.

Dr. Cooper summarized the findings, noting that GMP-cannabidiol was generally well-tolerated and that the incidence of cardiac-related side effects was low and comparable to the placebo. These safety results are promising as two larger trials focusing on the efficacy and safety of GMP-cannabidiol are currently in progress.

Results from the Phase II ARCHER trial, which is examining patients with acute myocarditis, are anticipated later in 2025. Meanwhile, the Phase III MAVERIC trial, targeting patients with recurrent pericarditis, is expected to provide findings in 2026.