Updated May 2026 · ClinicalTrials.gov

RECRUITINGPhase 3INTERVENTIONAL

Colchicine Versus Placebo in Acute Myocarditis Patients

Q: Who can participate in NCT05855746?

Eligibility for this trial depends on the specific inclusion and exclusion criteria set by the sponsor. The plain-English summary above translates the most important criteria into accessible language; the official clinical text is preserved in the collapsible section underneath. Whether you fit any specific trial is a medical decision your doctor needs to confirm — bring the trial information to your treating physician for a full review against your medical history.

Q: How do I contact the trial site for NCT05855746?

Contact information registered with ClinicalTrials.gov is shown in the sidebar of this page. Before reaching out, confirm with your treating physician that this trial is appropriate for your situation. The trial site will then walk you through the screening process to determine final eligibility.

Q: Is participating in a clinical trial safe?

Clinical trials in the United States are regulated by the FDA and overseen by Institutional Review Boards (IRBs) that review the protocol for safety. Risk varies by trial — Phase 1 studies test new treatments in humans for the first time, while Phase 3 trials use treatments that have already passed earlier safety screening. The informed consent document for any specific trial details the known risks and what to expect. Discuss those risks with your physician before deciding whether to participate.

Q: Where can I verify the data on this page?

Every detail on this page comes directly from the ClinicalTrials.gov API. Click "View on ClinicalTrials.gov" in the sidebar to see the official, unmodified record. The federal record is always authoritative; this page is a structured presentation with a plain-English eligibility translation. For background on how clinical trials are regulated, see the FDA drug approval process documentation.

Colchicine Versus Placebo in Acute Myocarditis Patients to Reduce Late Gadolinium Enhancement Mass on Cardiac Magnetic Resonance and the Risk of Clinical Outcomes: The ARGO Trial

Colchicine Versus Placebo in Acute Myocarditis Patients (NCT05855746) is a Phase 3 interventional studying Acute Myocarditis, sponsored by Assistance Publique - Hôpitaux de Paris. RECRUITING as of the most recent ClinicalTrials.gov update. Talk to your doctor before contacting the trial site.

About This Trial

Myocarditis is an inflammatory disease of the heart, mostly caused by viruses. Patients with acute myocarditis are exposed to several complications: recurrence, ventricular arrhythmias (from 5 to 30%), heart failure (5-10%), death or heart transplantation (\< 4%). To date, there is no specific treatment for myocarditis. Patient management only focuses upon empirical optimal care of arrhythmia and heart failure. There is a strong rationale for using colchicine in acute myocarditis: * the IL1 (Interleukin1) pathway plays a detrimental role in acute myocarditis. NLRP3 (NOD-like receptor family, pyrin domain containing 3) inflammasome assembly, and subsequent IL-1beta production, are profoundly inhibited by colchicine. * colchicine has been shown to improve cardiac outcomes in inflammatory cardiac disorders, including pericarditis, coronary artery disease, and post pericardiotomy syndrome. * In murine model of CVB3-induced myocarditis (coxsackievirus B3), colchicine improved myocarditis through reduction of NLRP3 activity. * Small case series with improvement of left ejection fraction in myocarditis following low-dose colchicine in addition to conventional heart failure therapy have been reported. With its pleiotropic anti-inflammatory effect in the pro-inflammatory cascade, reducing the myocardial damage and cell death induced during myocarditis, colchicine has the potential to reduce the risk of heart failure and ventricular arrhythmias. Finally, colchicine is a drug widely available, at low cost, and has a long and well-known safety record.

What Stage of Research Is This?

Phase 3 trials confirm efficacy and safety in large patient groups (often 300–3,000+) and form the evidence base for an FDA approval submission. For Acute Myocarditis, Phase 3 studies typically randomize participants between the investigational treatment and either a placebo or current standard of care. A successful Phase 3 result is the threshold most treatments need to clear before regulatory approval.

This trial is currently recruiting participants. The sponsor has registered the study with ClinicalTrials.gov as actively enrolling, which means new applicants who meet the eligibility criteria can be considered for screening. Trial status can change between updates — confirm current recruiting status with the study contact before traveling for a screening visit.

A target enrollment of 300 participants makes this a sizable late-stage trial. Studies in this range typically have enough power to detect clinically meaningful differences from a comparator and to characterize less-common side effects.

Who May Be Eligible (Plain English)

Who May Qualify: - Symptom onset of 28 days or less, - Myocarditis initially presenting with chest pain and/or Heart failure symptoms and/or palpitations - Troponins superior to 99 percentile of reference value, at any time between admission and inclusion - Myocarditis diagnostic confirmation (by Contrast-Enhanced Cardiac Magnetic Resonance (CMR), according to the Lake Louise criteria (2009 or later), - No evidence for ischemic heart disease on coronary angiography or coronary computed tomography angiography for patients with age superior to 40-year-old with one or more cardiovascular risk factor (hypertension, smoking, hypercholesterolemia, diabetes, personal or family history of coronary artery disease), - Woman of child-bearing age with an effective contraception method according to the investigator for the duration of treatment and one month after, - Man accepting effective contraception for the duration of treatment and one month after, - Participant with affiliation to the French Health Care System "sécurité sociale", - Written willing to sign a consent form of the patient obtained. Who Should NOT Join This Trial: - Cardiogenic shock requiring inotropes or vasopressors (patients with inotropes discontinued for more than 24 hours can be enrolled) - Giant cell myocarditis or eosinophilic myocarditis - Acute coronary syndrome or known coronary stenosis superior to 50% - Toxic cardiomyopathy - Active chronic inflammatory disease, chronic active infection, evolving cancer - A recent severe sepsis (7 days) - Hypersensitivity to Investgational Medical Product's active substances (colchicine) or to any of the excipients (including lactose, sucrose, microcrystalline cellulose, colloidal silica, magnesium stearate, colourants : E127, Dual Red 40 ) ...See full criteria on ClinicalTrials.gov Always talk to your doctor about whether this trial is right for you.

These are translations of the protocol\'s inclusion and exclusion criteria, simplified for patients and caregivers. The original clinical text appears below. Eligibility is ultimately confirmed by the trial site\'s screening process — this summary is a starting point for a conversation with your doctor, not a final determination.

Original Eligibility Criteria

View original clinical language

Inclusion Criteria: * Symptom onset of 28 days or less, * Myocarditis initially presenting with chest pain and/or Heart failure symptoms and/or palpitations * Troponins superior to 99 percentile of reference value, at any time between admission and inclusion * Myocarditis diagnostic confirmation (by Contrast-Enhanced Cardiac Magnetic Resonance (CMR), according to the Lake Louise criteria (2009 or later), * No evidence for ischemic heart disease on coronary angiography or coronary computed tomography angiography for patients with age superior to 40-year-old with one or more cardiovascular risk factor (hypertension, smoking, hypercholesterolemia, diabetes, personal or family history of coronary artery disease), * Woman of child-bearing age with an effective contraception method according to the investigator for the duration of treatment and one month after, * Man accepting effective contraception for the duration of treatment and one month after, * Participant with affiliation to the French Health Care System "sécurité sociale", * Written informed consent of the patient obtained. Exclusion Criteria: * Cardiogenic shock requiring inotropes or vasopressors (patients with inotropes discontinued for more than 24 hours can be enrolled) * Giant cell myocarditis or eosinophilic myocarditis * Acute coronary syndrome or known coronary stenosis superior to 50% * Toxic cardiomyopathy * Active chronic inflammatory disease, chronic active infection, evolving cancer * A recent severe sepsis (7 days) * Hypersensitivity to Investgational Medical Product's active substances (colchicine) or to any of the excipients (including lactose, sucrose, microcrystalline cellulose, colloidal silica, magnesium stearate, colourants : E127, Dual Red 40 ) * Any known contra-indication to CMR or associated contract products (claustrophobia; intra-ocular metal foreign bodies, clips such as cerebral, carotid, or aortic aneurysm, cochlear implants, any implant held in by magnet, history of hypersensitivity to gadoteric acid or to gadolinium contrast agents or to meglumine). Patients with an implantable cardioverter-defibrillator (ICD) or pacemaker (PM) are also excluded due to the risk of imaging artifacts, which may compromise the reliable quantification of late gadolinium enhancement (LGE). * Chronic treatment with corticosteroids or Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) or high-dose aspirin or immunosuppressant. * Sarcoidosis * Severe liver (Child Pugh C) or known renal dysfunction (known Glomerular Filtration Rate (GFR) less or equal to 30 ml/min according Cockroft), * Cytopenia : hemoglobin less than 100 grams/L, white blood cell count less than 3.0 G/L, platelet count less than 100 G/L between admission and inclusion (within 7 days) * Major digestive disorders (chronic diarrhea, inflammatory disease of the digestive tract as uncontrolled ulcerative colitis or active Crohn disease) * Immunosuppression, spinal cord aplasia * Hemopathy * Hypereosinophilia more than 0.5 G/L between admission and inclusion * Pregnant or nursing women, where pregnancy is defined as the state of a female after conception and until the termination of gestation, confirmed by a positive local laboratory test, * Administration of any investigational drug or participation in another interventional trial, within 30 days before randomization, * Participant under treatment having an interaction with colchicine \[macrolides (telithromycin, azithromycin, clarithromycin, dirithromycin, erythromycin, josamycin, midecamycin, roxithromycin), pristinamycin,, cyclosporine, verapamil, all protease inhibitors, telaprevir, CYP3A4 powerful inhibitors, azole antifungals, vitamin K antagonists\] * Participant under legal protection: under guardianship (trusteeship or curatorship)

Treatments Being Tested

DRUG

Colchicine Pill

Participant receive, in addition to standard of care therapy, six months of colchicine (at a dose of 0.5 mg twice daily, morning and evening) beginning maximum 72 hours post-randomization. The standard of care is defined according to the European consensus paper as follow: All participants without contraindication receive a betablockers, and heart failure ESC (European Society of Cardiology) guidelines directed medical therapies if LVEF \< 50% (Left Ventricular Ejection Fraction), including ACE (Angiotensin-Converting Enzyme) inhibitors, diuretics if indicated. The choice of the dosage and the drug is left at the investigator decision. During the six months of the treatment administration, in case of severe adverse reaction (such as nausea and/or diarrhea during five days), a dose reduction could be considered by the investigator: half of the study protocol dose could be accepted (0.5 mg per day in the morning). In case of remaining adverse reactions, the study drug should be stopped.

DRUG

Placebo

Participant receive, in addition to standard of care therapy, six months of placebo (at a dose of 0.5 mg twice daily, morning and evening) beginning maximum 72 hours post-randomization. The standard of care is defined according to the European consensus paper as follow: All participants without contraindication receive a betablockers, and heart failure ESC (European Society of Cardiology) guidelines directed medical therapies if LVEF \< 50% (Left Ventricular Ejection Fraction), including ACE (Angiotensin-Converting Enzyme) inhibitors, diuretics if indicated. The choice of the dosage and the drug is left at the investigator decision.

Locations (2)

Trial sites listed on ClinicalTrials.gov for this study. Site activation status can vary — confirm with the specific site before traveling for a screening visit.

Unité de Soins Intensifs Cardiologiques - Hôpital Cardiovasculaire Louis Pradel

Bron, France

Institut de Cardiologie - APHP Pitié Salpêtrière

Paris, France

How to Talk to Your Doctor About This Trial

Bring the printable summary of this trial — including the NCT ID (NCT05855746), the sponsor (Assistance Publique - Hôpitaux de Paris), and the key eligibility criteria — to your next appointment. Your doctor can review the inclusion and exclusion criteria against your medical history, lab values, and current treatments to assess whether you are likely to qualify. They can also help you weigh whether trial participation makes sense alongside your existing care plan.

Useful questions to walk through together: What does the trial protocol require beyond standard care? How long is the active treatment phase, and how long is follow-up? Are there study visits at sites I can reach? Who pays for the trial-specific procedures, and who pays for standard-of-care portions? See our 25 questions to ask about clinical trials guide for a more complete checklist.

Authoritative Sources

The official record for this trial lives on ClinicalTrials.gov — the federal registry maintained by the National Library of Medicine at NIH. For background on how this trial fits into the FDA approval pathway, see the FDA drug approval process. For oncology-specific guidance for patients considering trials, the National Cancer Institute publishes patient-oriented overviews. International trial registries are aggregated by the WHO ICTRP.

Frequently Asked Questions

What is the NCT05855746 clinical trial studying?

Who can participate in NCT05855746?

Eligibility for this trial depends on the specific inclusion and exclusion criteria set by the sponsor. The plain-English summary above translates the most important criteria into accessible language; the official clinical text is preserved in the collapsible section underneath. Whether you fit any specific trial is a medical decision your doctor needs to confirm — bring the trial information to your treating physician for a full review against your medical history.

How do I contact the trial site for NCT05855746?

Contact information registered with ClinicalTrials.gov is shown in the sidebar of this page. Before reaching out, confirm with your treating physician that this trial is appropriate for your situation. The trial site will then walk you through the screening process to determine final eligibility.

Is participating in a clinical trial safe?

Clinical trials in the United States are regulated by the FDA and overseen by Institutional Review Boards (IRBs) that review the protocol for safety. Risk varies by trial — Phase 1 studies test new treatments in humans for the first time, while Phase 3 trials use treatments that have already passed earlier safety screening. The informed consent document for any specific trial details the known risks and what to expect. Discuss those risks with your physician before deciding whether to participate.

Where can I verify the data on this page?

Every detail on this page comes directly from the ClinicalTrials.gov API. Click "View on ClinicalTrials.gov" in the sidebar to see the official, unmodified record. The federal record is always authoritative; this page is a structured presentation with a plain-English eligibility translation. For background on how clinical trials are regulated, see the FDA drug approval process documentation.

How This Page Is Built

Every field on this page is pulled directly from the ClinicalTrials.gov API v2 — no estimates, no proxies. The plain-English eligibility translation is generated from the original protocol text and reviewed for fidelity to the underlying clinical criteria. The original clinical text remains visible in the collapsible section above so users and clinicians can verify the translation. Read the full methodology for the data pipeline and known limitations.

Source: ClinicalTrials.gov API v2 record for NCT05855746. Maintained by the National Library of Medicine at NIH. Public domain. Cite as: "TrialFinderData. NCT05855746. Data: ClinicalTrials.gov."

Medical disclaimer: This page is informational, not medical advice. Talk to your doctor about whether a clinical trial is right for you.

Last updated 2026-05-08 · Data from ClinicalTrials.gov.