Extended Time Window Intravenous Thrombolysis Registry for Acute Ischemic Stroke (EXTEND-IVT)

Extended Time Window Intravenous Thrombolysis Registry for Acute Ischemic Stroke (EXTEND-IVT Registry)

The EXTEND-IVT Registry is a prospective, multicenter, observational cohort study designed to evaluate the effectiveness and safety of intravenous thrombolysis administered beyond 4.5 hours after last known well in patients with acute ischemic stroke (AIS) in routine clinical practice across China.

Study Overview

• Status: Not yet recruiting
• Conditions: Stroke; Acute Ischemic Stroke
• Intervention / Treatment: Drug: Intravenous Thrombolysis

Detailed Description

This prospective, multicenter, observational cohort registry enrolls adult patients (≥18 years) with acute ischemic stroke who receive intravenous thrombolysis more than 4.5 hours after last known well. Patient selection, imaging strategies, thrombolytic agent choice, dosing, and concomitant therapies are determined by treating physicians according to local clinical practice, without study-mandated intervention.

The primary outcome is the proportion of patients achieving a modified Rankin Scale (mRS) score of 0-1 at 90 ± 14 days. This registry describes real-world patient characteristics, treatment patterns, and outcomes of extended time window intravenous thrombolysis, and explores factors associated with clinical outcomes to inform patient selection and future clinical practice.

• Study Type: Observational
• Enrollment (Estimated): 3000

Contacts and Locations

• Study Contact: Name: Xinguang Yang; Email: yangxinguang0926@163.com
• Study Contact Backup: Name: Mingyi Bao; Phone Number: 86-20-81332619; Email: baomy@mail2.sysu.edu.cn

Study Locations

• China
  • Guangdong
    • Guangzhou, Guangdong, China
      • Sun Yat-sen Memorial Hospital, Sun Yat-sen University
  • Hunan
    • Guankou, Hunan, China
      • Liuyang Jili Hospital

Participation Criteria

Eligibility Criteria

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

• Sampling Method: Probability Sample

Study Population

Adult patients (≥18 years) with acute ischemic stroke who receive intravenous thrombolysis more than 4.5 hours after last known well as part of standard clinical care.

Description

Inclusion Criteria:

• 1. Age ≥ 18 years
• 2. Clinical diagnosed of acute ischemic stroke
• 3. Time from last known well (LKW) to initiation of intravenous thrombolysis > 4.5 hours (including wake-up stroke and unwitnessed stroke)
• 4. Received intravenous thrombolysis
• 5. Provided written informed consent

Exclusion Criteria:

• 1. Any condition judged by the investigator to make the participant unsuitable for study participation or follow-up (e.g., psychiatric disorders, cognitive impairment, or emotional disturbances).

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Extended time window intravenous thrombolysis	Drug: Intravenous Thrombolysis; Not applicable as this is an observational study.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The modified Rankin Scale score (mRS) 0-1	The proportion of mRS score 0-1 or a return to baseline if the pre-stroke mRS score ≥2 at 90±14 days. The modified Rankin Scale is a 7-point ordinal scale ranging from 0 to 6, with higher scores indicating greater disability (0 = no symptoms; 6 = death).	90±14 days

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Level of disability	The shift analysis of the mRS scores at 90±14 days. The modified Rankin Scale is a 7-point ordinal scale ranging from 0 to 6, with higher scores indicating greater disability (0 = no symptoms; 6 = death).	90±14 days
The modified Rankin Scale score (mRS) 0-2	The proportion of mRS score 0-2 at 90±14 days	90±14 days
The modified Rankin Scale score (mRS) 0-3	The proportion of mRS score 0-3 at 90±14 days	90±14 days
Change in neurologic deficit (NIHSS score) at 24 hours	Change in neurologic deficit (NIHSS score) from baseline to 24±12 hours after intravenous thrombolysis. The National Institutes of Health Stroke Scale (NIHSS) ranges from 0 to 42, with higher scores indicating more severe neurologic deficit.	24±12 hours
The modified Rankin Scale score (mRS) 0-1 at 1 year	The proportion of mRS score 0-1 at 1 year ± 60 days	1 year ± 60 days
Stroke recurrence within 90 days	Stroke recurrence and time to recurrence within 90 days	90±14 days
Stroke recurrence within 1 year	Stroke recurrence and time to recurrence within 1 year	1 year ± 60 days
Change in neurologic deficit (NIHSS score) at 7 days or discharge	Change in neurologic deficit (NIHSS score) from baseline to 7±1 days or at discharge, if earlier. The National Institutes of Health Stroke Scale (NIHSS) ranges from 0 to 42, with higher scores indicating more severe neurologic deficit.	7±1 days

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Symptomatic intracranial hemorrhage	Rate of symptomatic intracranial hemorrhage within 36 hours after intravenous thrombolysis (European Cooperative Acute Stroke Study [ECASS] III classification)	36 hours
Any intracranial hemorrhage	Rate of any intracranial hemorrhage within 36 hours after intravenous thrombolysis	36 hours
Serious adverse events during hospitalization	Safety will be assessed according to common terminology criteria for adverse events (CTCAE)	7±1 days
Mortality within 90 days	All-cause mortality within 90 days	90±14 days
Mortality within 1 year	All-cause mortality within 1 year	1 year ± 60 days

Collaborators and Investigators

• Sponsor: Sun Yat-Sen Memorial Hospital of Sun Yat-Sen University
• Investigators: Principal Investigator: Yamei Tang, Sun Yat-sen Memorial Hospital of Sun Yat-sen University; Principal Investigator: Yong He, Liuyang Jili Hospital

Study record dates

Study Major Dates

• Study Start (Estimated): April 1, 2026
• Primary Completion (Estimated): December 1, 2028
• Study Completion (Estimated): December 1, 2029

Study Registration Dates

• First Submitted: March 30, 2026
• First Submitted That Met QC Criteria: April 10, 2026
• First Posted (Actual): April 17, 2026

Study Record Updates

• Last Update Posted (Actual): April 17, 2026
• Last Update Submitted That Met QC Criteria: April 10, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Cerebrovascular Disorders; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Vascular Diseases; Cardiovascular Diseases; Ischemic Stroke; Stroke
• Other Study ID Numbers: SYSKY-2026-177-01

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: The IPD will be available from the Principal Investigators (Prof. Yamei Tang and Prof. Yong He) upon reasonable request.
• IPD Sharing Time Frame: 6 months after the study completion.
• IPD Sharing Access Criteria: The IPD will be available from the Principal Investigators (Prof. Yamei Tang and Prof. Yong He) upon reasonable request.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL

Drug and device information, study documents

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