gms | German Medical Science

56. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie e. V. (DGNC)
3èmes journées françaises de Neurochirurgie (SFNC)

Deutsche Gesellschaft für Neurochirurgie e. V.
Société Française de Neurochirurgie

07. bis 11.05.2005, Strasbourg

Clazosentan: a novel selective endothelin A receptor antagonist, prevents cerebral vasospasm following aneurysmal subarachnoid hemorrhage

Clazosentan: ein neuer selektiver Endothelin A Rezeptor Antagonist, verhindert den zerebralen Vasospasmus nach aneurysmatischer Subarachnoidalblutung

Meeting Abstract

  • corresponding author P. Vajkoczy - Neurochirurgische Klinik, Universitätsklinikum Mannheim
  • B. Meyer - Neurochirurgische Klinik, Universitätsklinikum Bonn
  • S. Weidauer - Institut für Neuroradiologie, Johann-Wolfgang-Goethe-Universität Frankfurt am Main
  • A. Raabe - Neurochirurgische Klinik, Johann-Wolfgang-Goethe Universität Frankfurt am Main
  • C. Thome - Neurochirurgische Klinik, Universitätsklinikum Mannheim
  • F. Ringel - Neurochirurgische Klinik, Universitätsklinikum Bonn
  • V. Breu - Actelion Pharmaceuticals Ltd, Allschwil, Switzerland
  • P. Schmiedek - Neurochirurgische Klinik, Universitätsklinikum Mannheim

Deutsche Gesellschaft für Neurochirurgie. Société Française de Neurochirurgie. 56. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie e.V. (DGNC), 3èmes journées françaises de Neurochirurgie (SFNC). Strasbourg, 07.-11.05.2005. Düsseldorf, Köln: German Medical Science; 2005. Doc11.05.-13.05

The electronic version of this article is the complete one and can be found online at:

Published: May 4, 2005

© 2005 Vajkoczy et al.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License ( You are free: to Share – to copy, distribute and transmit the work, provided the original author and source are credited.




To investigate the safety and efficacy of the novel endothelin A (ETA) receptor antagonist clazosentan in patients with aneurysmal subarachnoid hemorrhage (SAH) following surgical aneurysm clipping.


The study consisted of two parts: a double-blind, randomized part A (clazosentan 0.2 mg/kg/h versus placebo starting within 48 h post SAH up to day 14) on which statistical inference was performed and an open-label Part B (clazosentan 0.4 mg/kg/h for 12 h followed by 0.2 mg/kg/h up to day 14 for patients with established angiographic vasospasm) that was for exploratory purposes only. The primary efficacy endpoint was the incidence/severity of angiographic vasospasm at day 8 after SAH.


34 patients (Hunt and Hess grade 3-4, Fisher grade of 3 or higher) were recruited and 32 (15 clazosentan, 17 placebo) were retained in the Intent-To-Treat population; 19 patients entered part B. In part A, treatment with clazosentan resulted in a reduced incidence of angiographic cerebral vasospasm (40% vs 88%, p=0.008). Also, vasospasm severity was reduced in the clazosentan group (p=0.012). In part B, 50% of assessable patients initially treated with placebo demonstrated reversal of their angiographic vasospasm following initiation of clazosentan. The incidence of new infarctions in the clazosentan and placebo group was 15% and 44%, respectively (p=0.130). There was no adverse event pattern indicating a specific organ toxicity of clazosentan.


This study indicates that clazosentan reduces the frequency and severity of cerebral vasospasm following severe aneurysmal SAH with an incidence/severity of adverse events comparable to placebo.