Efficacy and Safety of Interleukin-6 Receptor Inhibitor Combined With Endovascular Treatment in Patients With Acute Anterior Circulation Large Vessel Occlusion Stroke -2 (IRIS-2)

Efficacy and Safety of Interleukin-6 Receptor Inhibitor Combined With Endovascular Treatment in Patients With Acute Anterior Circulation Large Vessel Occlusion Stroke: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial-2 (IRIS-2)

This study is a randomized, double-blind, placebo-controlled clinical trial. Investigators aim to assess the efficacy and safety of interleukin-6 receptor inhibitor combined with endovascular treatment in patients with acute anterior circulation large vessel occlusion stroke.

Study Overview

• Status: Active, not recruiting
• Conditions: Acute Ischemic Stroke
• Intervention / Treatment: Drug: Tocilizumab; Drug: Placebo

Detailed Description

The study population are patients with acute anterior circulation large vessel occlusion stroke and planned to undergo endovascular treatment. All participants are randomly assigned in a 1:1 ratio to the tocilizumab group or the placebo group. In tocilizumab group, participants will receive tocilizumab combined endovascular treatment. And in placebo group, participants will receive placebo combined endovascular treatment. All participants will be visited immediately postoperatively, at 24 hours, 7 days, and 90 days after randomization.

• Study Type: Interventional
• Enrollment (Estimated): 692
• Phase: Phase 3

Contacts and Locations

Study Locations

• China
  • Beijing, China, 100053
    • Xuanwu Hospital, Capital Medical University
  • Beijing, China
    • Beijing Red Cross Emergency Medical Center
  • Shenzhen, China
    • Shenzhen Longhua District People's Hospital
  • Anhui
    • Suzhou, Anhui, China
      • Suzhou Hospital of Anhui Medical University
    • Suzhou, Anhui, China
      • Si Country People's Hospital
    • Suzhou, Anhui, China
      • Suixi County Hospital
  • Fujian
    • Zhangzhou, Fujian, China
      • Zhangzhou Municipal Hospital
  • Guangxi
    • Qinzhou, Guangxi, China
      • Lingshan County People's Hospital
  • Hebei
    • Langfang, Hebei, China
      • JingDong ZhongMei Hospital
    • Qinhuangdao, Hebei, China
      • The second Hospital of Qinhuangdao
    • Tangshan, Hebei, China
      • Tangshan Workers Hospital
    • Tangshan, Hebei, China
      • Yutian Hospital
  • Heilongjiang
    • Harbin, Heilongjiang, China
      • The First Affiliated Hospital of Harbin Medical University
  • Henan
    • Anyang, Henan, China
      • The People's Hospital of Anyang
    • Hebi, Henan, China
      • Jun County People's Hospital
    • Jiaozuo, Henan, China
      • Jiaozuo No.2 People's Hospital
    • Luoyang, Henan, China
      • Luoyang Central Hospital
    • Luoyang, Henan, China
      • Mengjin County People's Hospital
    • Nanyang, Henan, China
      • Nanyang Central Hospital
    • Nanyang, Henan, China
      • Nanyang Nanshi Hospital
    • Nanyang, Henan, China
      • Tanghe County People's Hospital
    • Nanyang, Henan, China
      • Nanyang Second People's Hospital
    • Puyang, Henan, China
      • Puyang Oilfield General Hospital
    • Shangqiu, Henan, China
      • Shangqiu No.1 People's Hospital
    • Shangqiu, Henan, China
      • Ningling County People's Hospital
    • Xinxiang, Henan, China
      • Xinxiang Central Hospital
    • Xinxiang, Henan, China
      • Huixian People's Hospital
    • Xinxiang, Henan, China
      • The First Affiliated Hospital of Henan Medical University
    • Zhengzhou, Henan, China
      • Henan Provincial People's Hospital
    • Zhoukou, Henan, China
      • Xihua County People's Hospital
  • Hubei
    • Wuhan, Hubei, China
      • Tianyou Hospital Affliated to Wuhan University of Science &Technology
    • Xiangyang, Hubei, China
      • Xiangyang NO.1 People's Hospital
  • Inner Mongolia
    • Xing’an, Inner Mongolia, China
      • Xing'an league People's Hospital
  • Jiangsu
    • Nantong, Jiangsu, China
      • NanTong First People's Hospital
  • Shandong
    • Binzhou, Shandong, China
      • Binzhou Medical University Hospital
    • Dongying, Shandong, China
      • People's Hospital of Dongying
    • Linyi, Shandong, China
      • Linyi People's Hospital
    • Linyi, Shandong, China
      • Linshu Country People's Hospital
    • Qingdao, Shandong, China
      • Qingdao Huangdao District Hospital of Traditional Chinese Medicine
    • Zibo, Shandong, China
      • Zibo Central Hospital
    • Zibo, Shandong, China
      • Yiyuan Country People's Hospital
  • Shanxi
    • Jincheng, Shanxi, China
      • Jincheng People's Hospital
    • Taiyuan, Shanxi, China
      • Shanxi Bethune Hospital
    • Taiyuan, Shanxi, China
      • Shanxi Medical University First Hospital
    • Xianyang, Shanxi, China
      • The People's Hospital of Xianyang
    • Yulin, Shanxi, China
      • Daliuta Experimental District People's Hospital of Shenmu City
  • Wuhan
    • Zhongxiang, Wuhan, China
      • Zhongxiang Traditional Chinese Medical Hospital
  • Zhejiang
    • Jiaxing, Zhejiang, China
      • Jiaxing First Hospital
    • Lishui, Zhejiang, China
      • Lishui Central Hospital
    • Ningbo, Zhejiang, China
      • Ningbo NO.2 Hospital
    • Ningbo, Zhejiang, China
      • NingBo Medical Center LiHuiLi Hospital
    • Taizhou, Zhejiang, China
      • Taizhou Hospital of Zhejiang Province affiliated to Wenzhou Medical University
    • Wenzhou, Zhejiang, China
      • Wenzhou People's Hospital
    • Yueqing, Zhejiang, China
      • Yueqing People's Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

1. Age 18 years or greater, male or female;
2. Acute ischemic stroke caused by occlusion of intracranial segment of the internal carotid artery, middle cerebral artery M1 or proximal/dominant M2 segment;
3. Decided to undergo emergency endovascular treatment;
4. Time from stroke onset to arterial puncture within 24 hours;
5. National Institutes of Health Stroke Scale (NIHSS) score ≥ 6;
6. Signed informed consent from the patients or the legally authorized representatives.

Exclusion Criteria:

1. Intracerebral hemorrhage, epidural hematoma, subdural hematoma, intraventricular hemorrhage, or subarachnoid hemorrhage;
2. Pre-stroke modified Rankin scale (mRS) score >1;
3. Known allergy to tocilizumab or excipients;
4. Known allergy to iodinated contrast agents;
5. Anticipated difficulty in completing endovascular treatment due to vascular tortuosity;
6. History of congenital or acquired bleeding disorders, coagulation factor deficiency diseases, or thrombocytopenic diseases;
7. Systolic blood pressure ≥180mmHg or diastolic blood pressure ≥110mmHg despite blood pressure control;
8. Neutrophils <2×109 /L;
9. Platelets <100×109 /L;
10. Blood glucose <2.8mmol/L (50 mg/dL) or >22.2mmol/L (400 mg/dL);
11. Serum alanine aminotransferase (ALT) or aspartate aminotransferase (AST) levels >2 times the upper limit of normal;
12. Known recent or current serum creatinine >2 times the upper limit of normal or estimated glomerular filtration rate (eGFR) <60 mL/min;
13. Pregnant, lactating, or planning pregnancy within 90 days;
14. Severe mental disorders or inability to comply with informed consent and follow-up requirements due to dementia;
15. Concurrent malignant tumors or severe systemic diseases with expected survival of less than 90 days;
16. Presence of autoimmune diseases or use of immunosuppressive drugs;
17. Systemic infectious diseases;
18. Participation in another interventional clinical study within 30 days before randomization or currently participating in another interventional clinical study;
19. Considered by the investigator to have other conditions that might affect compliance or preclude participation in this study.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Quadruple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Tocilizumab group; Endovascular treatment combined 240 mg tocilizumab injection once.	Drug: Tocilizumab; 240 mg of tocilizumab injection will be diluted in 0.9% NaCl solution to prepare a total solution volume of 100 mL. The solution will be administered via intravenous infusion immediately after randomization, and no later than 30 minutes, with an infusion duration of more than 1 hour.
Placebo Comparator: Placebo group; Endovascular treatment combined equivalent volume of placebo once.	Drug: Placebo; An equivalent volume of placebo will be diluted in 0.9% NaCl solution to prepare a total solution volume of 100 mL. The solution will be administered via intravenous infusion immediately after randomization, and no later than 30 minutes, with an infusion duration of more than 1 hour.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
modified Rankin Scale (mRS) score at 90 days	The mRS ranges from 0 to 6, with higher scores indicating worse outcomes.	90 days

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Mortality at 90 days		90 days
Proportion of patients with mRS score 0-2 at 90 days		90 days
Proportion of patients with mRS score 0-1 at 90 days		90 days
Infarct volume at 24 hours		24 hours
Proportion of Barthel Index (BI) 95-100 at 90 days		90 days
Incidence of symptomatic intracerebral hemorrhage within 24 hours		24 hours
Incidence of any intracerebral hemorrhage within 24 hours		24 hours
Proportion of patients with pneumonia at 7 days or at early discharge		7 days or at early discharge
National Institutes of Health Stroke Scale (NIHSS) score at 7 days or at early discharge	The NIHSS ranges from 0 to 42, with higher scores indicating worse outcomes.	7 days or at early discharge
EuroQol Five-Dimension Five-Level Questionnaire (EQ-5D-5L) at 90 days	The EQ-5D-5L includes 5 dimensions: mobility, self-care, usual activities,pain/discomfort, and anxiety/depression. Each dimension has 5 levels: 1= no problems, 2= slight problems, 3= moderate problems, 4= severe problems, and 5= extreme problems. Higher scoresindicating worse quality of life.	90 days

Collaborators and Investigators

• Sponsor: Capital Medical University

Study record dates

Study Major Dates

• Study Start (Actual): December 5, 2025
• Primary Completion (Estimated): September 16, 2026
• Study Completion (Estimated): September 16, 2026

Study Registration Dates

• First Submitted: November 23, 2025
• First Submitted That Met QC Criteria: November 23, 2025
• First Posted (Actual): December 4, 2025

Study Record Updates

• Last Update Posted (Actual): June 12, 2026
• Last Update Submitted That Met QC Criteria: June 11, 2026
• Last Verified: June 1, 2026

More Information

Terms related to this study

• Keywords: Stroke; Endovascular Treatment; Interleukin-6 Receptor Inhibitor
• Additional Relevant MeSH Terms: Cerebrovascular Disorders; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Vascular Diseases; Cardiovascular Diseases; Ischemic Stroke; Stroke; tocilizumab
• Other Study ID Numbers: IRIS-2

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Related data will be shared if full study protocol and statistical analysis plan are provided with reasonable design.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No