Idorsia Pharmaceuticals Ltd: Idorsia submits NDA for clazosentan to Japanese PMDA Allschwil, Switzerland - March 1, 2021 Idorsia Ltd (SIX: IDIA) today announced the submission of a New Drug Application (NDA) to the Japanese Pharmaceuticals and Medical Devices Agency (PMDA) for clazosentan, a fast-acting, selective endothelin A (ET A) receptor antagonist, for the prevention of cerebral vasospasm, vasospasm-related cerebral infarction and cerebral ischemic symptoms after aneurysmal subarachnoid hemorrhage (aSAH). The application is supported by replicated results from the Japanese registration program which consisted of two double-blind, randomized, placebo-controlled studies assessing the efficacy and safety of clazosentan in reducing vasospasm-related morbidity and all-cause mortality events in adult Japanese patients following aSAH. Patients were randomized to receive continuous infusion of either 10 mg/hr clazosentan or placebo for up to 15 days following the onset of aSAH. The two studies followed the same design, with one enrolling 221 patients whose aneurysm was secured by surgical clipping and the other enrolling 221 patients whose aneurysm was secured by endovascular coiling.