A Phase 2 interventional study of Combined antioxidant therapy and Placebo in Acute Myocardial Infarction (AMI), ST Elevation (STEMI) Myocardial Infarction and Reperfusion Injuries, Myocardial, sponsored by University of Chile. Not yet recruiting at 1 site in Chile. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-08-20.
Sponsored by University of Chile · Phase 2, Interventional, and Treatment
The goal of this clinical trial is to learn if a combined antioxidant therapy (CAT) can reduce heart damage caused by the return of blood flow after blocked arteries are reopened in adults with ST-elevation myocardial infarction (STEMI) treated with primary percutaneous coronary intervention (PCI). It will also learn about the safety of this treatment. The main questions it aims to answer are:
Researchers will compare CAT to placebo (a look-alike infusion with no active drug) to see if the treatment lowers infarct size after STEMI.
Participants will:
Acute myocardial infarction (AMI) remains as a leading cause of morbidity and mortality worldwide. In patients with ST-segment elevation myocardial infarction (STEMI), early reperfusion with primary percutaneous coronary intervention (PCI) is the standard treatment to limit myocardial injury. However, reperfusion induces additional damage, referred to as ischemia-reperfusion injury (IRI), which has been estimated to account for up to 50% of final infarct size. Oxidative stress is a key mechanism in IRI and contributes to lipid peroxidation, inflammation, and regulated cell death pathways. Prior pharmacologic approaches directed at single components of this process have shown limited and inconsistent clinical benefit, supporting evaluation of multitarget strategies.
This study is a phase II, randomized, double-blind, placebo-controlled, parallel-group superiority trial designed to evaluate the efficacy and safety of a combined antioxidant therapy (CAT) in patients with acute STEMI undergoing primary PCI. CAT consists of ascorbate, N-acetylcysteine, and deferoxamine. These agents were selected to target complementary mechanisms relevant to IRI: reactive oxygen species scavenging, glutathione replenishment, redox modulation and inflammatory response, and iron chelation with inhibition of iron-dependent lipid peroxidation. The study will randomly assign participants in a 1:1 ratio to receive CAT or matching placebo in addition to guideline-based STEMI treatment.
The intervention will be initiated before reperfusion and maintained during primary PCI in order to ensure drug exposure during the early reperfusion phase. Both groups will receive standard-of-care treatment for STEMI, including primary PCI and guideline-directed medical therapy.
The trial is designed as a signal-seeking phase II study using infarct size as the primary efficacy endpoint. Infarct size measured by cardiac magnetic resonance (CMR) is a mechanistically relevant endpoint in cardioprotection trials and has established prognostic value. In this study, CMR will be performed during the index hospitalization to quantify infarct size as a percentage of left ventricular mass. Additional imaging variables, myocardial injury biomarkers, oxidative stress and inflammatory biomarkers, pharmacokinetic measurements, short-term clinical outcomes, and safety data will be collected to support interpretation of the primary analysis. These assessments include left ventricular systolic function, hs-cTnI, CK, CK-MB, plasma concentrations of the study drugs, and 30-day follow-up for clinical events and adverse events.
The planned sample size is 46 participants. The study is powered to detect a large between-group difference in infarct size, consistent with its exploratory phase II design. Accordingly, the trial is intended to determine whether CAT demonstrates a sufficiently large efficacy signal, together with an acceptable safety profile, to support further evaluation in a larger trial.
Safety monitoring will include systematic collection of adverse events and serious adverse events during hospitalization and through day 30. Events will be recorded using Medical Dictionary for Regulatory Activities (MedDRA) terminology.
This trial will provide phase II data on the efficacy, safety, pharmacokinetics, and mechanistic effects of a multitarget antioxidant strategy administered during primary PCI in patients with STEMI.
850 studies on the registry are indexed under ST Elevation Myocardial Infarction; 197 are open to participants now.
This study's planned enrollment of 46 is below the median of 194 across 527 interventional studies indexed under ST Elevation Myocardial Infarction.
Browse ST Elevation Myocardial Infarction studies →University of Chile is the lead sponsor of 194 studies on the registry; 38 are open to participants now.
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Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
The New York Heart Association’s four classes of how much heart failure limits physical activity.
Studies set their own limit — many outside heart failure leave out class III–IV, while heart failure studies may ask for a particular class. Check the class this study names.
The study doctor’s estimate of how long someone is likely to live. Criteria use it so that people can stay in the study long enough for it to answer its question.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
NYHA class (heart failure)
The New York Heart Association’s four classes of how much heart failure limits physical activity.
Studies set their own limit — many outside heart failure leave out class III–IV, while heart failure studies may ask for a particular class. Check the class this study names.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Life expectancy
The study doctor’s estimate of how long someone is likely to live. Criteria use it so that people can stay in the study long enough for it to answer its question.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants receive combined antioxidant therapy consisting of ascorbate, N-acetylcysteine, and deferoxamine, initiated before reperfusion and maintained during primary PCI, in addition to standard-of-care treatment for STEMI.
Drug: Combined antioxidant therapy
Participants receive matching placebo infusion initiated before reperfusion and maintained during primary PCI, in addition to standard-of-care treatment for STEMI.
Drug: Placebo
Combined Antioxidant Therapy consisting of ascorbate, N-acetylcysteine and deferoxamine
Matching placebo infusion administered before reperfusion and during primary PCI.
Infarct Size
Infarct size by CMR: infarct size will be expressed as a percentage of left ventricular (LV) mass (%LV). Infarct size will be measured using late gadolinium enhancement with manual contouring.
Time frame: 3-7 days after Primary Coronary Intervention
Cardiac Function and structure by CMR
Left ventricular ejection fraction (LVEF), left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV), and left ventricular mass measured by cardiac magnetic resonance imaging.
Time frame: 3-7 days after Primary Percutaneous Coronary Intervention
Cardiac function by Transthoracic echocardiography
Left ventricular systolic and diastolic function parameters, regional wall motion abnormalities, cardiac chamber sizes, and right ventricle systolic function
Time frame: Before hospital discharge, approximately 3-7 days after Primary Percutaneous Coronary Intervention
Myocardial Injury Biomarkers
High sensitivity cardiac Troponin I, creatine kinase (CK), and CK-MB. For each biomarker, peak value, area under the curve (AUC 0-48 hours), and change from baseline will be assessed.
Time frame: Samples will be obtained at baseline (prior to infusion), immediately after Primary Percutaneous Coronary Intervention (PCI), and at 12 hours, 24 hours, and 48 hours after PCI.
Biomarkers of oxidative stress
Ferric reducing ability of plasma (FRAP), malondialdehyde, F2-isoprostanes, reduced glutathione/oxidized glutathione ratio (GSH/GSSG), enzymatic activity of superoxide dismutase, glutathione peroxidase, and catalase.
Time frame: Samples will be obtained at baseline (prior to infusion), immediately after Primary Percutaneous Coronary Intervention (PCI), and at 12 hours, 24 hours, and 48 hours after PCI.
Biomarkers of inflammation
C-reactive protein (CRP) and interleukin (IL)-18
Time frame: Samples will be obtained at baseline, 12 hours, and 24 hours after Primary Percutaneous Coronary Intervention.
Clinical outcomes
Clinical outcomes will include all-cause mortality, cardiovascular associated mortality, reinfarction, target-vessel revascularization, and heart failure.
Time frame: 30 days after PCI
Safety outcomes
Adverse events (AEs) and serious adverse events (SAEs) will be recorded regardless of suspected causality. Events will be coded using Medical Dictionary for Regulatory Activities (MedDRA) standardized terminology.
Time frame: Through hospitalization and up to day 30 after Primary Percutaneous Coronary Intervention.
Plan to share: No — Deidentified individual participant data will not be publicly shared because of ethical, confidentiality, and institutional restrictions. The study protocol and statistical analysis plan will be made available after publication of the main results.
No publications or documents are linked to this record.
This study is not yet recruiting, as verified in Aug 2026. You cannot join it, but the record below documents what was studied.
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