A Phase 2 interventional study of CardiolRx in Acute Myocarditis, sponsored by Cardiol Therapeutics Inc.. Completed at 37 sites in 5 countries. Open to participants aged 18 Years to 75 Years. Per ClinicalTrials.gov, last updated 2026-09-30.
Sponsored by Cardiol Therapeutics Inc. · Phase 2, Interventional, and Treatment
Multi-center, double-blind, placebo-controlled, parallel group design. Patients with myocarditis will be screened and, if eligible, randomized within 10 days of the diagnostic CMR to CardiolRx or placebo.
CardiolRx is pharmaceutically produced Cannabidiol and is free of tetrahydrocannabinol (THC\<5 ppm). The treatment period is 12 weeks; a last follow-up visit is scheduled one week after the last treatment, 13 weeks after randomization. Study assessments include Cardiac Magnetic Resonance imaging (CMR), ECG monitoring, the Kansas City Cardiomyopathy Questionnaire (KCCQ), the Columbia-Suicide Severity Rating Scale (C-SSRS) as well as physical exams and laboratory tests.
The primary and secondary outcome parameters are measured by CMR. Additional outcomes include clinical endpoints and changes in inflammatory and biomarkers.
Rationale:
Myocarditis is an acute inflammatory condition of the myocardium. Presentation of the disease may be fulminant and necessitate cardiac support, or even result in sudden cardiac death; milder cases are usually self-limiting but may progress to dilated cardiomyopathy with eventual end-stage heart failure. Other than treatments for associated heart failure there are no specific indicated treatments for myocarditis. CardiolRxTM (cannabidiol [CBD] solution), which is known to have anti-inflammatory properties, is being investigated to treat the underlying inflammatory process and thereby favorably modify acute myocarditis. The primary endpoints of the trial are cardiac magnetic resonance measures of left ventricular systolic function (ejection fraction and longitudinal strain) and myocardial edema (extra cellular volume) which have been shown to predict long term prognosis of patients with acute myocarditis.
Multi-center, double-blind, randomized, placebo-controlled, parallel group design. 1:1 randomization; treatment will be stratified within sites.
Patients diagnosed with acute myocarditis by a biopsy or a CMR will be screened within 10 days of the diagnostic CMR. Informed consent will be obtained at this point. For patients who have been diagnosed using an EMB, a CMR needs to be performed as well, which will be included in the informed consent form (ICF).Eligible patients will then be randomized within 10 days from the CMR assessment.
Baseline assessments include the following: Clinical assessment, including vital signs, ECG, 24-hr Holter, chest x-ray; Hematology and blood chemistry, NYHA classification, C SSRS and KCCQ. Frozen plasma will be retained for central analysis of hs-troponin, NT-proBNP and inflammatory markers.
Study treatment needs to be taken with food and will be initiated in the evening of Day 1, after all baseline assessments have been completed and the patient has been randomized.
Oral administration is as follows:
Week 2 (p.m. dose of Day 7 to a.m. dose of Day 14):
5 mg/kg of body weight b.i.d. CardiolRxTM or placebo
7.5 mg/kg of body weight b.i.d. CardiolRxTM or placebo • Week 4 to end of treatment period (p.m. dose of Day 21 to
a.m. dose of last day of treatment period at week 12): 10 mg/kg of body weight b.i.d. CardiolRxTM or placebo
If the next higher dose after each study drug increase is not tolerated, the dose will be reduced to the previous tolerated dose.
Every week (before the next dose increase) the patient will be re-evaluated. This includes ECG monitoring at approximately 5 hours post-morning dose (time of Tmax) to surveil for deleterious effects on ECG intervals (particularly the QTc interval) and rhythm. Drug titration will be dependent on investigator or designate interrogation of the ECGs and the absence of new, clinically significant abnormalities on those ECGs.
Vital signs, concurrent medication and Adverse Events (AEs), including Serious Adverse Events (SAEs) will be recorded, blood chemistry including liver function tests, hematology as well as INR assessments will be carried out.
Final efficacy assessments (including a second CMR) will take place after 12 weeks of study treatment. A final safety assessment will take place after 13 weeks, 1 week after completion of study treatment.
Cardiol Therapeutics Inc. is the lead sponsor of 4 studies on the registry; 1 is open to participants now.
Counted across the registry records on this site, refreshed daily.
Diagnosed with acute myocarditis including:
Exclusion Criteria:
* Week 1 (p.m. dose of Day 1 to a.m. dose of Day 7): 2.5 mg/kg of body weight b.i.d. CardiolRxTM or placebo * Week 2 (p.m. dose of Day 7 to a.m. dose of Day 14): 5 mg/kg of body weight b.i.d. CardiolRxTM or placebo * Week 3 (p.m. dose of Day 14 to a.m. dose of Day 21): 7.5 mg/kg of body weight b.i.d. CardiolRxTM or placebo * Week 4 to end of treatment period (p.m. dose of Day 21 to a.m. dose of last day of treatment period at week 12): 10 mg/kg of body weight b.i.d. CardiolRxTM or placebo
Drug: CardiolRx
* Week 1 (p.m. dose of Day 1 to a.m. dose of Day 7): 2.5 mg/kg of body weight b.i.d. CardiolRxTM or placebo * Week 2 (p.m. dose of Day 7 to a.m. dose of Day 14): 5 mg/kg of body weight b.i.d. CardiolRxTM or placebo * Week 3 (p.m. dose of Day 14 to a.m. dose of Day 21): 7.5 mg/kg of body weight b.i.d. CardiolRxTM or placebo * Week 4 to end of treatment period (p.m. dose of Day 21 to a.m. dose of last day of treatment period at week 12): 10 mg/kg of body weight b.i.d. CardiolRxTM or placebo
Drug: CardiolRx
Eligible patients will be randomized to receive CardiolRx or placebo. Intervention will be administered orally (via syringe) with food twice daily.
Also known as: Cannabidiol
Extracellular Volume (ECV)
Change of ECV from baseline at 12 weeks, measured by cardiac Cardiac MRI. ECV is measuring the degree of edema and fibrosis. The unit of measure was percentage. It was the percentage of myocardial tissue that is extracellular space (i.e. fraction of the myocardium occupied by extracellular matrix and interstitial fluid).
Time frame: 12 weeks post randomization
Global Longitudinal Strain (GLS)
The outcome was the change in GLS from baseline at 12 weeks, measured by cardiac Cardiac MRI. GLS is a predictor of cardiac function. The unit of measure is percentage. It is the percent change in myocardial length relative to its original (end-diastolic) length along the long axis. Longitudinal strain during systole is usually negative, because the ventricle shortens; normal peak GLS in healthy adults is around -20% (i.e., 20% shortening relative to original length)
Time frame: 12 weeks post randomization
Change in Left-ventricular Ejection Fraction (LVEF) From Baseline at 12 Weeks
Left-ventricular ejection fraction (LVEF) as measured by Cardiac MRI at 12 weeks. LVEF is a measure of cardiac function. The unit of measure is percentage. It is the percent of end-diastolic blood volume in the left ventricle that is ejected with each systolic contraction. Mathematically, LVEF = (stroke volume/end-diastolic volume) x 100.
Time frame: 12 weeks post randomization
Change in Left-ventricular Mass From Baseline at 12 Weeks
Left-ventricular mass at week 12, measured with cardiac MRI. Unit of measure is grams (g) of myocardium. The mass of left-ventricular myocardial tissue was calculated from lCMR using geometric assumptions (e.g., Devereux/ASE cube formula) and myocardial density.
Time frame: From baseline to 12 weeks of treatment
166 patients signed informed consent between July 28, 2022, and October 31,2024, in 29 centers in Brazil; France; Israel and the United States. There were 57 screening failures and 109 patients were randomized to either CardiolRx™ (N=56) or Placebo (N=53). All randomized patients started the IMP and completed the study as planned - no patient withdrew prematurely from follow-up. In total, 11 patients discontinued the IMP before the Week 12 visit, 6 on CardiolRx and 5 on placebo.
| Milestone | CardiolRx | Placebo |
|---|---|---|
| Started | 56 | 53 |
| Completed | 56 | 53 |
| Not completed | 0 | 0 |
Change of ECV from baseline at 12 weeks, measured by cardiac Cardiac MRI. ECV is measuring the degree of edema and fibrosis. The unit of measure was percentage. It was the percentage of myocardial tissue that is extracellular space (i.e. fraction of the myocardium occupied by extracellular matrix and interstitial fluid).
| percentage of tissue volume outside cell | CardiolRx | Placebo |
|---|---|---|
| Extracellular Volume (ECV) | -1.88 ± 3.25 | -1.60 ± 4.57 |
The outcome was the change in GLS from baseline at 12 weeks, measured by cardiac Cardiac MRI. GLS is a predictor of cardiac function. The unit of measure is percentage. It is the percent change in myocardial length relative to its original (end-diastolic) length along the long axis. Longitudinal strain during systole is usually negative, because the ventricle shortens; normal peak GLS in healthy adults is around -20% (i.e., 20% shortening relative to original length)
| % of change in ventricle length | CardiolRx | Placebo |
|---|---|---|
| Global Longitudinal Strain (GLS) | -0.68 ± 3.6 | -0.62 ± 3.68 |
Left-ventricular ejection fraction (LVEF) as measured by Cardiac MRI at 12 weeks. LVEF is a measure of cardiac function. The unit of measure is percentage. It is the percent of end-diastolic blood volume in the left ventricle that is ejected with each systolic contraction. Mathematically, LVEF = (stroke volume/end-diastolic volume) x 100.
| percentage | CardiolRx | Placebo |
|---|---|---|
| Change in Left-ventricular Ejection Fraction (LVEF) From Baseline at 12 Weeks | 0.65 ± 8.38 | 1.75 ± 9.05 |
Left-ventricular mass at week 12, measured with cardiac MRI. Unit of measure is grams (g) of myocardium. The mass of left-ventricular myocardial tissue was calculated from lCMR using geometric assumptions (e.g., Devereux/ASE cube formula) and myocardial density.
| gram | CardiolRx | Placebo |
|---|---|---|
| Change in Left-ventricular Mass From Baseline at 12 Weeks | -11.11 ± 15.32 | -2.83 ± 23.39 |
The total Extracellular Volume (ECV) was calculated in mL using the following formula:Total ECV volume (mL) = ܸECV fraction (%) x LV mass (g)/ 1.05 where 1.05 = the specificgravity of myocardium in g/mL. It is the absolute extracellular volume of the tissue or body compartment, reported as physical volume instead of fraction or percent.
| mL | CardiolRx | Placebo |
|---|---|---|
| Change in Extracellular Volume (ECV) in ml From Baseline at 12 Weeks | -5.96 ± 7.35 | -2.73 ± 9.48 |
Collected over 16 weeks in France and 13 weeks for rest of the world (Brazil, Israel and US). Non-serious events are listed at a 0% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Cannabidiol, Pharmaceutically Produced With < 5 Ppm THC | 0/56 (0%) | 6/56 (10.7%) | 42/56 (75%) |
| Placebo | 0/53 (0%) | 3/53 (5.7%) | 35/53 (66%) |
| Event | Cannabidiol, Pharmaceutically Produced With < 5 Ppm THC | Placebo |
|---|---|---|
| PalpitationCardiac disorders | 0/56 | 1/53 |
| Alanine aminotransferase increasedInvestigations | 1/56 | 1/53 |
| Aspartate aminotransferase increasedInvestigations | 0/56 | 1/53 |
| HypocalcemiaMetabolism and nutrition disorders | 0/56 | 1/53 |
| MyocarditisCardiac disorders | 1/56 | 0/53 |
| Ventricular TachycardiaCardiac disorders | 1/56 | 0/53 |
| GastritisGastrointestinal disorders | 1/56 | 0/53 |
| Chest painGeneral disorders | 1/56 | 0/53 |
| Transaminases increasedInvestigations | 1/56 | 0/53 |
| TremorNervous system disorders | 1/56 | 0/53 |
| Event | Cannabidiol, Pharmaceutically Produced With < 5 Ppm THC | Placebo |
|---|---|---|
| DiarrheaGastrointestinal disorders | 18/56 | 11/53 |
| Chest painGeneral disorders | 9/56 | 4/53 |
| AstheniaGeneral disorders | 1/56 | 7/53 |
| NauseaGastrointestinal disorders | 5/56 | 2/53 |
| Alanine aminotransferase increasedInvestigations | 5/56 | 3/53 |
| PalpitationsCardiac disorders | 1/56 | 4/53 |
| NasopharyngitisInfections and infestations | 0/56 | 3/53 |
| RashSkin and subcutaneous tissue disorders | 3/56 | 1/53 |
modified ITT analysis population
| Age, Continuous(years) | CardiolRx | Placebo | Total |
|---|---|---|---|
| Mean | 35.8 ± 15.35 | 39.6 ± 15.47 | 37.7 ± 15.45 |
| Sex: Female, Male(Participants) | CardiolRx | Placebo | Total |
|---|---|---|---|
| Female | 10 | 9 | 19 |
| Male | 39 | 41 | 80 |
| Race (NIH/OMB)(Participants) | CardiolRx | Placebo | Total |
|---|---|---|---|
| American Indian or Alaska Native | 0 | 0 | 0 |
| Asian | 0 | 1 | 1 |
| Native Hawaiian or Other Pacific Islander | 0 | 0 | 0 |
| Black or African American | 5 | 2 | 7 |
| White | 38 | 41 | 79 |
| More than one race | 0 | 1 | 1 |
| Unknown or Not Reported | 6 | 5 | 11 |
| Region of Enrollment(participants) | CardiolRx | Placebo | Total |
|---|---|---|---|
| United States | 4 | 4 | 8 |
| Brazil | 22 | 28 | 50 |
| Israel | 7 | 7 | 14 |
| France | 16 | 11 | 27 |
| Global longitudinal strain (GLS)(%) | CardiolRx | Placebo | Total |
|---|---|---|---|
| Mean | -15.35 ± 3.10 | -15.34 ± 4.06 | -15.35 ± 3.60 |
| Extracellular volume (ECV)(%) | CardiolRx | Placebo | Total |
|---|---|---|---|
| Mean | 29.74 ± 4.47 | 30.83 ± 4.31 | 30.29 ± 4.40 |
| Left-ventricular ejection fraction (LVEF)(%) | CardiolRx | Placebo | Total |
|---|---|---|---|
| Mean | 61.90 ± 8.88 | 59.35 ± 10.79 | 60.61 ± 9.93 |
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From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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Cardiol Therapeutics Inc.