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Hamostaseologie 2012; 32(03): 228-233
DOI: 10.5482/HAMO-12-05-0009
Review
Schattauer GmbH

Atopaxar

A novel player in antiplatelet therapy?AtopaxarEin neuer Mitspieler der antithrombozytären Therapie?
T. Wurster
1   Medizinische Klinik III, Eberhard-Karls-Universität Tübingen, Germany
,
A. E. May
1   Medizinische Klinik III, Eberhard-Karls-Universität Tübingen, Germany
› Author Affiliations
Further Information

Publication History

received: 25 May 2012

accepted: 19 June 2012

Publication Date:
28 December 2017 (online)

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Summary

Atopaxar, also known as E 5555 is a novel reversible protease-activated receptor-1 (PAR-1) thrombin receptor antagonist. To date, Atopaxar has been investigated in phase II trials with focus on safety and tolerability in patients with acute coronary syndromes or stable coronary artery disease on top of standard antiplatelet therapy. Atopaxar was generally well tolerated, however a rise in liver enzymes and prolongation of the QTcF interval were observed. The data suggest, that atopaxar administration may promote some minor bleeding complications, but does not seem to significantly increase the risk of major bleeding. Although not powered for efficacy, the currently available data suggest potential benefits in patients at high risk for recurrent ischemic events on top of standard antiplatelet therapy. In conclusion, more studies (e.g. phase III) are needed to evaluate efficacy and safety of atopaxar.

Zusammenfassung

Atopaxar, auch bekannt als E 5555 ist ein neuer, reversibler Antagonist des Thrombin Protease-aktivierten Rezeptors-1 (PAR-1). Atopaxar wurde bisher in Phase-II-Studien in Hinblick auf Sicherheit und Verträglichkeit bei Patienten mit akutem Koronarsyndrom oder stabiler koronarer Herzkrankheit zusätzlich zur antithrombozytären Standardtherapie untersucht. Atopaxar wurde im Allgemeinen gut vertragen, jedoch waren eine Erhöhung der Leberenzyme und eine Verlängerung der QTZeit auffällig. Die zusätzliche Einnahme von Atopaxar scheint zu einer Zunahme leichter Blutungskomplikationen zu führen, jedoch ohne das Auftreten schwerwiegender Blutungskomplikationen relevant zu erhöhen. Obwohl bisherige Studien nicht primär die Wirksamkeit von Atopaxar untersuchten, gibt es Hinweise dafür dass Patienten mit hohem Risiko für das Auftreten ischämischer Ereignisse von der zusätzlichen Einnahme von Atopaxar profítieren. Weitere (Phase-III-)Studien sind nötig, die Wirksamkeit und Sicherheit von Atopaxar untersuchen.

Keywords

Atopaxar - E 5555 - thrombin - PAR-1 - acute coronary syndrome

Schlüsselwörter

Atopaxar - E 5555 - Thrombin - PAR-1 - akutes Koronarsyndrom
 

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