BACKGROUND: Augmentation of collateral circulation is an alternative method to improve cerebral hypoperfusion when revascularization is not suitable. DL-3-n-butylphthalide (NBP) has been shown to enhance cerebral collateral circulation and improve cerebral blood flow (CBF) in previous studies. The objective of this study was to explore the effect of NBP on cerebral hemodynamic impairment due to atherosclerotic stenosis in internal carotid system. METHODS: This was a double-blind, placebo-controlled, randomized clinical trial conducted in 38 Chinese hospitals between 14 January 2022, and 11 April 2024. Eligible participants were aged 35-85 years with ≥ 70% stenosis in unilateral internal carotid artery or middle cerebral artery, accompanied by cerebral hypoperfusion and no recent cerebral ischemic events. The patients were randomly assigned in a 1:1 ratio to a treatment group receiving 600 mg NBP daily or a placebo group receiving an ineffective dose of NBP daily for 4 weeks. The cerebral perfusion was assessed by computed tomography perfusion. The grades of cerebral perfusion change from baseline to 12 weeks were classified into amelioration, stabilization, and deterioration. The primary efficacy outcome was the percentage of patients achieving CBF amelioration. RESULTS: Of 485 enrolled patients (median age 63 years, 66.6% men), 244 were assigned to the NBP group and 241 to the placebo group. At the end of follow-up, 204 in the NBP group and 212 in the placebo group completed second cerebral perfusion. NBP group had 113 (55.4%) patients with CBF amelioration in stenotic territory and placebo group had 93 (43.9%) comparable patients at 12 weeks (risk ratio 1.32; 95% confidence interval 1.08-1.61; p = 0.006). CONCLUSIONS: For cerebral hypoperfusion from atherosclerotic stenosis in internal carotid system, NBP treatment resulted in a higher proportion of patients achieving CBF amelioration than placebo. TRIAL REGISTRATION: chictr.org.cn: ChiCTR2100053112.
Chen et al. (Thu,) studied this question.