Antifibrinolytic AgentsPhase 4PAATICSNCT06128330
Point-of-care Measurement of the Antifibrinolytic Activity of Tranexamic Acid in Cardiac Surgery
A Phase 4 study testing Tranexamic acid bolus 20 mg/kg, Tranexamic acid bolus 10 mg/kg and Tranexamic acid bolus 1 mg/kg in people with Antifibrinolytic Agents, run by Insel Gruppe AG, University Hospital Bern at 1 site in Switzerland.
Trial summary
Tranexamic acid (TXA) is a widely used antifibrinolytic agent that can reduce postoperative blood loss and packed red blood cell transfusions during cardiac surgery. Previous (in-vivo) studies have measured TXA plasma concentration and associated clinical effect (e.g. blood loss). Read more about this study
- Who is it for?
- Ages 18 to 90 years
- Conditions the study is for
- Antifibrinolytic Agents
- What is being tested?
- Tranexamic acid bolus 20 mg/kg, Tranexamic acid bolus 10 mg/kg and Tranexamic acid bolus 1 mg/kg
- Type of treatment
- Injection or infusion
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 322 participants
- Where
- 1 siteSwitzerland
- Study dates
- 15 Dec 2023to 31 Dec 2026
- Phase
- Phase 4
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 90 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Eligible patients:
- Over 18 years old
- Elective surgery
- Written informed consent
- Patient planned for aortocoronary artery bypass graft surgery, aortic valve replacement or mitral valve surgery (or a combination of these procedures)
- Normal renal function
- No previous intake of anticoagulants except acetylsalicylic acid in the preoperative period
Who cannot join
- Impaired renal function (eGFR < 30 ml/min.)
- History of seizure
- Pregnancy
- Inability to understand and sign the informed consent (e.g., language problems, dementia, psychological disorders)
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Switzerland1 site, 1 recruiting
- Recruiting
Dpt. Anesthesiology and pain Medicine
Bern, 3010
Gabor Erdoes, MD, +41316322726, gabor.erdoes@insel.ch
Annegret Kauert-Willms, MD, +41316322111, annegret.kauert@insel.ch
About this study
Tranexamic acid (TXA) is a widely used antifibrinolytic agent that can reduce postoperative blood loss and packed red blood cell transfusions during cardiac surgery. Previous (in-vivo) studies have measured TXA plasma concentration and associated clinical effect (e.g. blood loss). Patient blood management guidelines recommend the routine use of TXA in cardiac surgery, especially for procedures with a high risk of bleeding.
A new point-of-care viscoelastic diagnostic assay (tissue plasminogen activator assay, TPA assay) allows for a rapid determination of antifibrinolytic activity in a patient in the operating room making TXA dose adjustment easily possible intraoperatively. Currently, there is no consensus on the dosing of TXA and different protocols are used. Recommendations for high doses (e.g. 30 mg/kg followed by 16 mg/kg per hour during cardiac surgery with 2 mg/kg added to extracorporeal circulation) alternate with recommendations for low doses (e.g., 10 mg/kg followed by 1 mg/kg per hour for 12 hours).
Read more
Tranexamic acid administration increases the risk of postoperative seizure, a risk that appears to be dose dependant. A recent meta-analysis suggests that a single TXA bolus of 20 mg/kg is sufficient to reduce postoperative blood loss and packed red blood cell transfusion in patients undergoing aortocoronary bypass surgery. The calculations in the meta-analysis were, however, based on a simulation of blood concentrations of TXA by a pharmacokinetic model, so the results are subject to many uncertainties. The optimal TXA regimen for cardiac surgery, both in terms of efficacy and safety therefore remains uncertain and requires further investigation.
This study was invented to determine the actual levels of tranexamic acid in vivo to observe antifibrinolytic activity during cardiac surgery up to 48 hours after termination of surgery. The risk category is evaluated as risk category A as the study is a clinical trial examining the effect of drugs that are already authorized for the clinical use.
- Conditions
- Antifibrinolytic Agents
- Being tested
- Tranexamic acid bolus 20 mg/kg, Tranexamic acid bolus 10 mg/kg, Tranexamic acid bolus 1 mg/kg, Tranexamic acid continuous infusion of 1 mg/kg/h in the low dose group
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Tranexamic acid bolus 20 mg/kgDrug
Bolus of tranexamic acid in the standard dose group
Tranexamic acid bolus 10 mg/kgDrug
Bolus of tranexamic acid in the low dose group
Tranexamic acid bolus 1 mg/kgDrug
Bolus of tranexamic acid in the low dose group (to add into the CPB prime)
Tranexamic acid continuous infusion of 1 mg/kg/h in the low dose groupDrug
Tranexamic acid continuous infusion during the procedure
| Study group | Role | What they receive |
|---|---|---|
| Standard dose group | Active comparator | The standard dose group will receive a bolus of 20 mg/kg tranexamic acid after anaesthesia induction. Receives: Drug: Tranexamic acid bolus 20 mg/kg |
| Low dose group | Experimental | The low dose group will receive a bolus of 10 mg/kg tranexamic acid. In addition 1 mg/kg tranexamic acid will be added to the priming of the extracorporeal circuit (ECC) and a continuous infusion of 1mg/kg/h tranexamic acid will be started after the bolus infusion until the end of surgery. Receives: Drug: Tranexamic acid bolus 10 mg/kg; Drug: Tranexamic acid bolus 1 mg/kg; Drug: Tranexamic acid continuous infusion of 1 mg/kg/h in the low dose group |
What is being measured
The primary outcome is the main question the study is designed to answer.
TPA test
The primary endpoint of the study is if the antifibrinolytic activity as measured with the TPA assay. The result can be positive (no fibrinolysis and good antifibrinolytic activity) or negative (fibrinolysis and no antifibrinolytic activity).The TPA assay is performed at five different time points until the 2. postoperative day (48 hours).
Measured: 48 hours after completion of surgery
Secondary outcomes (1)
Chromatography
Secondary endpoint is the TXA concentration as measured by chromatography.
Measured: 48 hours after completion of surgery
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted13 Nov 2023
- Study start15 Dec 2023
- Primary completion31 Dec 2025 (estimated)
- Study completion31 Dec 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Antifibrinolytic AgentsStudies of the same condition, open and under way.
- More trials run by Insel Gruppe AG, University Hospital BernThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 4
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Enrolment
- 322 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Insel Gruppe AG, University Hospital Bern
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
- Investigators
- Annegret Kauert-Willms, MD, Principal investigator, University Hospital Berne
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06128330
- Sponsor's protocol ID
- 2022-02070
- Acronym
- PAATICS
- Status last verified
- Jun 2025
- First submitted
- 7 Nov 2023
- Last updated
- 6 Jun 2025
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 6 Jun 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Point-of-care Measurement of the Antifibrinolytic Activity of Tranexamic Acid in Cardiac Surgery
- ClinicalTrials.gov ID
- NCT06128330
- Acronym / sponsor ID
- PAATICS / 2022-02070
- Conditions
- Antifibrinolytic Agents
- Phase
- Phase 4
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 322 participants (estimated)
- Lead sponsor
- Insel Gruppe AG, University Hospital BernUniversity, hospital or other
- Study start
- 15 Dec 2023 (actual)
- Primary completion
- 31 Dec 2025 (estimated)
- Study completion
- 31 Dec 2026 (estimated)
- First posted
- 13 Nov 2023 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Tranexamic acid (TXA) is a widely used antifibrinolytic agent that can reduce postoperative blood loss and packed red blood cell transfusions during cardiac surgery. Previous (in-vivo) studies have measured TXA plasma concentration and associated clinical effect (e.g. blood loss). Patient blood management guidelines recommend the routine use of TXA in cardiac surgery, especially for procedures with a high risk of bleeding.
A new point-of-care viscoelastic diagnostic assay (tissue plasminogen activator assay, TPA assay) allows for a rapid determination of antifibrinolytic activity in a patient in the operating room making TXA dose adjustment easily possible intraoperatively. Currently, there is no consensus on the dosing of TXA and different protocols are used. Recommendations for high doses (e.g. 30 mg/kg followed by 16 mg/kg per hour during cardiac surgery with 2 mg/kg added to extracorporeal circulation) alternate with recommendations for low doses (e.g., 10 mg/kg followed by 1 mg/kg per hour for 12 hours).
Tranexamic acid administration increases the risk of postoperative seizure, a risk that appears to be dose dependant. A recent meta-analysis suggests that a single TXA bolus of 20 mg/kg is sufficient to reduce postoperative blood loss and packed red blood cell transfusion in patients undergoing aortocoronary bypass surgery. The calculations in the meta-analysis were, however, based on a simulation of blood concentrations of TXA by a pharmacokinetic model, so the results are subject to many uncertainties. The optimal TXA regimen for cardiac surgery, both in terms of efficacy and safety therefore remains uncertain and requires further investigation.
This study was invented to determine the actual levels of tranexamic acid in vivo to observe antifibrinolytic activity during cardiac surgery up to 48 hours after termination of surgery. The risk category is evaluated as risk category A as the study is a clinical trial examining the effect of drugs that are already authorized for the clinical use.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Standard dose group | Active comparator | Drug: Tranexamic acid bolus 20 mg/kgThe standard dose group will receive a bolus of 20 mg/kg tranexamic acid after anaesthesia induction. |
| Low dose group | Experimental | Drug: Tranexamic acid bolus 10 mg/kg, Drug: Tranexamic acid bolus 1 mg/kg, Drug: Tranexamic acid continuous infusion of 1 mg/kg/h in the low dose groupThe low dose group will receive a bolus of 10 mg/kg tranexamic acid. In addition 1 mg/kg tranexamic acid will be added to the priming of the extracorporeal circuit (ECC) and a continuous infusion of 1mg/kg/h tranexamic acid will be started after the bolus infusion until the end of surgery. |
Who may qualify
- Ages
- 18 to 90 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (7 listed)
- Over 18 years old
- Elective surgery
- Written informed consent
- Patient planned for aortocoronary artery bypass graft surgery, aortic valve replacement or mitral valve surgery (or a combination of these procedures)
- Normal renal function
Key exclusion criteria (4 listed)
- Impaired renal function (eGFR < 30 ml/min.)
- History of seizure
- Pregnancy
- Inability to understand and sign the informed consent (e.g., language problems, dementia, psychological disorders)
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Tranexamic acid bolus 20 mg/kgBolus of tranexamic acid in the standard dose group | Drug | Standard dose group |
| Tranexamic acid bolus 10 mg/kgBolus of tranexamic acid in the low dose group | Drug | Low dose group |
| Tranexamic acid bolus 1 mg/kgBolus of tranexamic acid in the low dose group (to add into the CPB prime) | Drug | Low dose group |
| Tranexamic acid continuous infusion of 1 mg/kg/h in the low dose groupTranexamic acid continuous infusion during the procedure | Drug | Low dose group |
Primary outcome
TPA test
Time frame: 48 hours after completion of surgery
The primary endpoint of the study is if the antifibrinolytic activity as measured with the TPA assay. The result can be positive (no fibrinolysis and good antifibrinolytic activity) or negative (fibrinolysis and no antifibrinolytic activity).The TPA assay is performed at five different time points until the 2. postoperative day (48 hours).
1 secondary outcome
Chromatography
Time frame: 48 hours after completion of surgery
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 6 Jun 2025.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Annegret Kauert-Willms, MD principal investigator
University Hospital Berne
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 4 study testing Tranexamic acid bolus 20 mg/kg, Tranexamic acid bolus 10 mg/kg and Tranexamic acid bolus 1 mg/kg in people with Antifibrinolytic Agents, run by Insel Gruppe AG, University Hospital Bern at 1 site in Switzerland.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 7 inclusion and 4 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 6 Jun 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Switzerland. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 4 studies take place after a treatment is approved, to learn more about its long-term benefits and risks in everyday use.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Gabor Erdoes, MD (++41 31 632 2726, Gabor.erdoes@insel.ch), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
TPA test (time frame: 48 hours after completion of surgery). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 6 Jun 2025.