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Recruiting Phase 3 NCT03998319

NCT03998319 A Study of Low-dose Intracoronary Thrombolytic Therapy in STEMI (Heart Attack) Patients.

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Clinical Trial Summary
NCT ID NCT03998319
Status Recruiting
Phase Phase 3
Sponsor University of Sydney
Condition STEMI
Study Type INTERVENTIONAL
Enrollment 445 participants
Start Date 2021-10-14
Primary Completion 2024-12-31

Eligibility & Interventions

Sex All sexes
Min Age 18 Years
Max Age N/A
Study Type INTERVENTIONAL
Interventions
Tenecteplase (1/3 systemic weight based dose)Sterile water for injection (WFI)

Eligibility Fast-Check

Enter your details for a quick preliminary check. This does not replace medical advice.

What to Expect as a Participant

You will actively receive the study intervention — which may be a drug, biologic, device, or procedure.

Phase 3 trials are large pivotal studies comparing the treatment to current standard of care or placebo. Your participation directly contributes to the evidence needed for regulatory approval.

This trial targets 445 participants in total. It began in 2021-10-14 with a primary completion date of 2024-12-31.

⚠ This information is for research awareness only. Always consult your physician before joining any clinical trial. Participation is voluntary and you may withdraw at any time.

Brief Summary

Heart attacks are caused by a blood clot blocking the blood vessels of the heart, preventing blood getting to the heart muscle. Opening up the artery with a balloon (angioplasty) and a small mesh tube (stent) although life saving can cause this clot to break up and get washed downstream, which can make the heart attack worse. The investigators can measure the amount of damage caused to the microcirculation by calculating the IMR (Index of Microcirculatory resistance). This can be measured by a wire in the coronary artery with a pressure sensor at the tip. If the IMR is elevated, it is suggestive of extensive microcirculatory damage. A clot dissolving medicine can be administered in the artery to try and reduce the IMR which can reduce damage to the heart muscle and improve outcomes. Impaired microcirculatory perfusion in patients as a result of ST-elevation myocardial infarction (STEMI) is associated with poor clinical outcomes. This project seeks to identify patients with impaired microcirculatory perfusion after STEMI and to assess whether acute improvement in microcirculatory perfusion in these patients by the use of intracoronary thrombolytic therapy results in improved clinical outcomes.

Eligibility Criteria

Inclusion Criteria: 1. Adult men and women aged over 18 who present with STEMI within 6 hours of symptom onset. Patients will be eligible if they have symptoms consistent with myocardial ischaemia (chest pain, dyspnoea) for at least 20 minutes accompanied by definite ECGs indicating STEMI as defined by Australian National Heart Foundation (NHF) guidelines 2. Willing and able to comply with all study requirements, including treatment, assessment and clinic visit attendances 3. Able to personally read and understand the Participant Information and Consent Form and provide written, signed and dated informed consent to participate in the study 4. (At time of PCI) Patient has received metallic drug-eluting stent 5. Participant consents to have a 3-7 day (discharge) and 6 month follow up cardiac MRI Exclusion Criteria: At the time of screening and/or prior to randomisation, no known; 1. Previous coronary bypass grafting 2. Other residual lesions with ≥50% diameter stenosis in the culprit vessel 3. Prior myocardial infarction in the target territory 4. Presence of contraindications to thrombolytic therapy (including history of stroke and recent brain surgery active internal bleeding; history of cerebrovascular accident; intracranial or intraspinal surgery, or trauma within 2 months; intracranial neoplasm, arteriovenous malformation, or aneurysm; known bleeding diathesis; and severe uncontrolled hypertension) 5. Presence of contraindications to adenosine infusion for IMR measurement including sinus node disease, moderate to severe bronchoconstrictive disease and second or third-degree atrioventricular (AV) block 6. Diagnosis of metastatic disease 7. Concurrent illness, including severe infection that may jeopardise the ability of the patient to undergo the procedures outlined in this protocol with reasonable safety 8. Serious medical or psychiatric conditions that might limit the ability of the patient to comply with the protocol 9. Pregnancy, lactation, or inadequate contraception. Women must be post-menopausal, infertile, or use a reliable means of contraception. Women of childbearing potential must have a negative pregnancy test done within 7 days prior to registration. Men must have been surgically sterilised or use a (double if required) barrier method of contraception. 10. Participation in any investigational study in the previous 30 days Other exclusion criteria: 11. (Cardiac MRI cohort only) Presence of contraindications to contrast enhanced MRI including severe claustrophobia, pregnancy, pacemakers, non-MRI compatible aneurysm clips, defibrillators and estimated glomerular filtration rate of \<30mL/min. (At time of PCI) 12. Patients who received GpIIb/IIIa treatment prior to IMR measurement 13. Patients who do not undergo primary PCI due to lack of severity of culprit lesion or other reasons.

Contact & Investigator

Central Contact

Martin Ng, MBBS (Hons)

✉ martin.ng@sydney.edu.au

📞 +614 3407 8507

Principal Investigator

Martin Ng, MBBS (Hons)

STUDY CHAIR

Royal Prince Alfred Hospital, Sydney, Australia

Frequently Asked Questions

Who can join the NCT03998319 clinical trial?

This trial is open to participants of all sexes, aged 18 Years or older, studying STEMI. Full inclusion and exclusion criteria are listed in the Eligibility Criteria section. Always confirm your eligibility with the research team before applying.

What phase is the NCT03998319 trial and what does that mean for participants?

Phase 3 trials are large-scale studies comparing the new treatment to existing standards of care or a placebo. They provide the evidence needed for regulatory approval. This trial targets 445 participants.

Is NCT03998319 currently recruiting?

Yes, NCT03998319 is actively recruiting participants. Contact the research team at martin.ng@sydney.edu.au for enrollment information.

Where is the NCT03998319 trial being conducted?

This trial is being conducted at Bankstown, Australia, Camperdown, Australia, Concord, Australia, Frenchs Forest, Australia and 11 additional locations.

Who is sponsoring the NCT03998319 clinical trial?

NCT03998319 is sponsored by University of Sydney. The principal investigator is Martin Ng, MBBS (Hons) at Royal Prince Alfred Hospital, Sydney, Australia. The trial plans to enroll 445 participants.

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