Thrombolysis With the Nonimmunogenic Staphylokinase for Acute Ischemic Stroke in FORPI Registry: An Observational Study

BACKGROUND: The nonimmunogenic staphylokinase is a recombinant staphylokinase with low immunogenicity, high thrombolytic activity, and fibrin selectivity approved in Russia for the acute ischemic stroke (AIS) thrombolytic therapy within 4.5 hours after symptom onset. We evaluated safety and efficacy outcomes of the nonimmunogenic staphylokinase usage in patients with AIS in the Fortelyzin Population Investigation registry. METHODS: Between March 2021 and October 2024, patients with AIS treated with the nonimmunogenic staphylokinase were enrolled in the prospective, open-label, internet-based, monitored, observational Fortelyzin Population Investigation registry. Demographics, risk factors, baseline stroke severity (defined by National Institutes of Health Stroke Scale), and onset to treatment time were recorded. Safety outcomes included symptomatic intracerebral hemorrhage (according to the ECASS III [European Cooperative Acute Stroke Study III] and SITS-MOST [Safe Implementation of Thrombolysis in Stroke—Monitoring Study] criteria) within 36 hours and all-cause mortality on day 90. Efficacy outcome was evaluated by functional independence using of modified Rankin Scale score of 0 to 2 on day 90. RESULTS: A total of 17 636 patients with AIS were treated with the nonimmunogenic staphylokinase in 329 centers participated in the Fortelyzin Population Investigation registry during the study period (median age 68 [60–75]; 56% male; median baseline National Institutes of Health Stroke Scale score, 11 [8–16] points; median onset to treatment time, 2.4 hours [1.8–3.1]). The rate of symptomatic intracerebral hemorrhage according to the ECASS III criteria was 2% (356/17 636; 1.8–2.2), to the SITS-MOST criteria, 2% (330/17 636; 1.8–2.1). All-cause mortality on day 90 was 9% (1588/17 636; 8.6–9.4). The number of patients with a modified Rankin Scale score of 0 to 2 on day 90 was 61% (10 799/17 636; 60.5–61.9). These safety and efficacy outcomes were comparable with FRIDA (Fortelyzin Randomized Investigation Compared With Alteplase) randomized clinical trial results. CONCLUSIONS: The presented data suggest that intravenous thrombolysis with the nonimmunogenic staphylokinase is safe and effective in routine clinical practice when used within 4.5 hours of AIS symptoms onset. These findings should encourage the wider usage of thrombolytic therapy with the nonimmunogenic staphylokinase for suitable patients.