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Taking people in AustriaPhase 3

Protamine after transcatheter aortic valve replacement for severe aortic stenosis

Tests protamine to reverse heparin after valve replacement in adults with severe aortic stenosis.

Key facts

Who runs it
Klinikum der Universitaet Muenchen AöR
Where
Innsbruck, AustriaSee the siteAlso in 1 other country, 3 sites
Registry title
PROTamine Application in patients underGOing tRAnScatheter aortic valve replacement (PROTAGORAS)
Status
Recruiting
Phase
Phase 3
People taking part
954 people, planned
Started
28 Mar 2025
Expected to end
28 Feb 2027
Type of study
Interventional
Record updated
7 July 2026

Who can take part

AI summary

From the trial's eligibility criteria. Machine-read from the registry text on this page, so it can be wrong. The registry text below and the trial team decide who can take part.

The trial is looking for adults aged 55 or older with severe aortic stenosis who are scheduled for TAVR through the groin artery. It tests whether giving protamine after the procedure to reverse heparin lowers bleeding and other serious problems.

Age
55 years or older (the record also lists a minimum age of 18 Years)
Sex
All
Disease stage
Severe aortic stenosis (narrowing of the main heart valve), with transfemoral TAVR (valve replacement through a groin artery) planned.
Earlier treatment
People cannot join if they had a heart artery stent or balloon procedure (PCI) within 4 weeks before TAVR. People on vitamin K antagonists cannot join if INR is above 1.8 before TAVR.

Main reasons for not taking part

  • Having a mechanical heart valve
  • Pregnant women and women who could become pregnant
  • Past allergic reaction to protamine, known heparin allergy, or past heparin-induced low platelet count
  • Taking direct oral anticoagulants that are not paused on the day of TAVR
  • Severe complications during the TAVR procedure, such as stroke or conversion to open surgery

The registry criteria, word for word

Show all 14 criteriaShow less

Who can take part

  • Age ≥55 years
  • Severe aortic stenosis
  • Scheduled for transfemoral TAVR
  • Willing to participate, able to understand and to consent, signed informed consent

Who cannot take part

  • Prior allergic reaction to protamine or increased anaphylactic risk according to the investigator’s discretion
  • Prior heparin-induced thrombocytopenia
  • Percutaneous coronary intervention within 4 weeks prior to TAVR
  • Subjects participating in another clinical trial with an investigational new drug or not commercially available and approved devices
  • Presence of mechanical heart valve
  • Known heparin allergy
  • Severe TAVR procedure complications (Annulus rupture, aortic dissection, coronary oc-clusion, cardiogenic shock, conversion to open surgery, pericardial tamponade, stroke, valve prosthesis dislocation, mechanical resuscitation not related to bleeding, any other acute TAVR procedure complication considered severe or life threatening by the investigator)
  • Patients on vitamin K antagonists if INR > 1.8 before TAVR procedure (last measure-ment within three days prior procedure)
  • Pregnant women and women of childbearing potential
  • Patients on direct oral anticoagulants if not paused on the day of TAVR procedure

Where in Austria

Also in 1 other country, 3 sites

  • Medical University InnsbruckInnsbruck, AustriaTaking people

About the trial

What the trial wants to find out

To assess the clinical benefit with respect to major bleeding and major ischemic events of post-procedural heparin reversal with protamine after transcatheter aortic valve replacement.

Questions to ask the study team

  1. How often do I need to come in, and for how long each time?
  2. Are travel costs paid?
  3. Can I keep my own doctor?
  4. What happens if I want to stop?

Contact the study team: see the registry record

Print a page for my doctor

Data and sources

Registry record
Listed on the EU's official list of trials (CTIS).
Official title
PROTamine Application in patients underGOing tRAnScatheter aortic valve replacement (PROTAGORAS)
Plain-language title
Protamine after transcatheter aortic valve replacement for severe aortic stenosisGenerated from the registry record. The registry title is the official one.
AI summary
From the trial's eligibility criteria. Read by machine on 14 November 2026.
Record updated
7 July 2026