Update on the INTEnsive ambulance-delivered blood pressure Reduction in hyper-ACute stroke Trial (INTERACT4): progress and baseline features in 2053 participants
Chen Chen,
Yapeng Lin,
Feifeng Liu,
Xiaoying Chen,
Laurent Billot,
Qiang Li,
Yiija Guo,
Hueiming Liu,
Lei Si,
Menglu Ouyang,
Chunfang Zhang,
Hisatomi Arima,
Philip M. Bath,
Gary A. Ford,
Thompson Robinson,
Else Charlotte Sandset,
Jeffrey L. Saver,
Nikola Sprigg,
H. Bart van der Worp,
Gang Liu,
Lili Song,
Jie Yang,
Gang Li,
Craig S. Anderson,
for the INTERACT4 Investigators
Affiliations
Chen Chen
Department of Neurology, Shanghai East Hospital, School of Medicine, Tongji University
Yapeng Lin
Department of Neurology, Clinical Medical College and The First Affiliated Hospital of Chengdu Medical College
Feifeng Liu
Department of Neurology, Shanghai East Hospital, School of Medicine, Tongji University
Xiaoying Chen
The George Institute for Global Health, Faculty of Medicine, UNSW
Laurent Billot
The George Institute for Global Health, Faculty of Medicine, UNSW
Qiang Li
The George Institute for Global Health, Faculty of Medicine, UNSW
Yiija Guo
Beijing Municipal Key Laboratory of Clinical Epidemiology, School of Public Health, Capital Medical University
Hueiming Liu
The George Institute for Global Health, Faculty of Medicine, UNSW
Lei Si
School of Health Sciences, Western Sydney University
Menglu Ouyang
The George Institute for Global Health, Faculty of Medicine, UNSW
Chunfang Zhang
Shanghai Pudong New Area Medical Emergency Centre
Hisatomi Arima
The George Institute for Global Health, Faculty of Medicine, UNSW
Philip M. Bath
Stroke Trials Unit, Mental Health & Clinical Neuroscience, University of Nottingham
Gary A. Ford
Oxford University Hospitals NHS Foundation Trust and University of Oxford
Thompson Robinson
College of Life Sciences and NIHR Leicester Biomedical Research Centre, University of Leicester
Else Charlotte Sandset
Department of Neurology, Oslo University Hospital
Jeffrey L. Saver
University of California
Nikola Sprigg
Stroke Trials Unit, Mental Health & Clinical Neuroscience, University of Nottingham
H. Bart van der Worp
Department of Neurology and Neurosurgery, University Medical Centre Utrecht
Gang Liu
Clinical Medical College and The First Affiliated Hospital of Chengdu Medical College
Lili Song
The George Institute for Global Health, Faculty of Medicine, UNSW
Jie Yang
Department of Neurology, Sichuan Academy of Medical Sciences & Sichuan Provincial People’s Hospital, University of Electronic Science and Technology of China
Gang Li
Department of Neurology, Shanghai East Hospital, School of Medicine, Tongji University
Craig S. Anderson
The George Institute for Global Health, Faculty of Medicine, UNSW
Abstract Background and aims Uncertainty persists over the effects of blood pressure (BP) lowering in acute stroke. The INTEnsive ambulance-delivered blood pressure Reduction in hyper-Acute stroke Trial (INTERACT4) aims to determine efficacy and safety of hyperacute intensive BP lowering in patients with suspected acute stroke. Given concerns over the safety of this treatment in the pre-hospital setting, particularly in relation to patients with intracerebral hemorrhage, we provide an update on progress of the study and profile of participants to date. Methods INTERACT4 is an ongoing multicentre, ambulance-delivered, randomized, open-label, blinded endpoint trial of pre-hospital BP lowering in patients with suspected acute stroke and elevated BP in China. Patients are randomized via a mobile phone digital system to intensive (target systolic BP [SBP] <140mmHg within 30 min) or guideline-recommended BP management. Primary outcome is an ordinal analysis of the full range of scores on the modified Rankin scale scores at 90 days. Results Between March 2020 and April 2023, 2053 patients (mean age 70 years, female 39%) were recruited with a mean BP 178/98 mmHg in whom 45% have a diagnosis of primary intracerebral hemorrhage upon arrival at hospital. At the time of presentation to hospital, the mean SBP was 160 and 170mmHg in the intensive and control groups (Δ10 mmHg), respectively. The independent data and safety monitoring board has not identified any safety concerns and recommended continuation of the trial. The sample size was reduced from 3116 to 2320 after meetings in August 2022 as the stroke mimic rate was persistently lower than initially estimated (6% vs 30%). The study is expected to be completed in late 2023 and the results announced in May 2024. Conclusions INTERACT4 is on track to provide reliable evidence of the effectiveness of ambulance-delivered intensive BP lowering in patients with suspected acute stroke. Trial registration ClinicalTrials.gov NCT03790800 ; registered on 2 January 2019. Chinese Trial Registry ChCTR1900020534 , registered on 7 January 2019.
