The Journal of Neurosurgery reports impact of clazosentan on cerebral vasospasm-related morbidity and all-cause mortality after aneurysmal subarachnoid hemorrhage
Idorsia Pharmaceuticals Ltd
Idorsia Pharmaceuticals Ltd
  • Results published in the Journal of Neurosurgery show that clazosentan significantly reduced the combined incidence of vasospasm-related morbidity and all-cause mortality post-aSAH with no unexpected safety findings.

  • The pivotal studies in Japanese patients supported the approval of Pivlaz™ (clazosentan) in Japan in January 2022, Pivlaz is expected to be available in April 2022.

Allschwil, Switzerland – April 4, 2022
Idorsia Ltd (SIX: IDIA) and Idorsia Pharmaceuticals Japan today announce the publication of “Effects of clazosentan on cerebral vasospasm-related morbidity and all-cause mortality after aneurysmal subarachnoid hemorrhage: two randomized phase 3 trials in Japanese patients” in the Journal of Neurosurgery1. Clazosentan, a selective endothelin A (ETA) receptor antagonist, significantly reduced the combined incidence of vasospasm-related morbidity and all-cause mortality post-aSAH with no unexpected safety findings1.

Aneurysmal subarachnoid hemorrhage (aSAH) is a sudden, life-threatening bleeding occurring in the subarachnoid space, caused by the rupture of an aneurysm.2,3 An urgent intervention involving endovascular coil embolization or microscopic clipping is required to prevent rerupture.2 Clot hemolysis and the release of vasoconstricting agents can contribute to cerebral vasospasm, which typically begins approximately 3 days after aSAH onset, peaks in severity at days 8–11, and resolves by day 21.4 If untreated, cerebral vasospasm can be a key factor of morbidity and mortality in patients with aSAH.2 Cerebral vasospasm may lead to delayed ischemic neurological deficit (DIND) in up to 40% of aSAH cases, and half of the patients with vasospasm develop cerebral infarction.3 With an occurrence of 22.5 per 100,000 person-years, aSAH is 2–3 times more frequent in Japan than in the rest of the world5 and is therefore a significant problem in this country.

Two prospective, multicenter, double-blind, randomized, placebo-controlled, pivotal Phase 3 studies assessing the efficacy and safety of clazosentan in reducing vasospasm-related morbidity and all-cause mortality events in adult Japanese patients post-aSAH, were conducted in parallel in 57 neuro surgical centers in Japan. Patients were randomized 1:1 to receive continuous infusion of either 10 mg/hr of clazosentan or placebo within 48 hours of the onset of aSAH for up to a cumulative maximum of 15 days after aSAH. Protocols were identical, each study enrolling 221 patients, except for the securing intervention, which was either endovascular coiling (JapicCTI-163369; the “coiling study”) or surgical clipping (JapicCTI-163368; the “clipping study”).