Post R, Germans MR, Tjerkstra MA, et al. - In this multicenter prospective, randomized, controlled, open-label trial with masked outcome assessment, researchers ascertained if ultra-early, short-term treatment with tranexamic acid improves clinical outcome at 6 months in patients with aneurysmal subarachnoid hemorrhage. Adult patients with spontaneous CT-proven subarachnoid hemorrhage were randomly assigned to treatment with tranexamic acid in addition to care as usual (tranexamic acid group) or care as usual only (control group). Nine hundred fifty-five patients (480 patients were randomly assigned to tranexamic acid and 475 patients to the control group) were recruited between July 24, 2013 and July 29, 2019. Ultra-early, short-term treatment with tranexamic acid did not improve clinical outcome at 6 months, as measured by the modified Rankin Scale, in patients with CT-proven subarachnoid hemorrhage, possibly caused by a ruptured aneurysm. Good clinical outcome was observed in 60% of 475 patients in the tranexamic acid group and 64% of 470 patients in the control group in the intention-to-treat analysis, while rebleeding after randomization and before aneurysm treatment occurred in 10% patients in the tranexamic acid and in 14% patients in the control group.