INTERACT4: emergency antihypertensive treatment in the ambulance proves feasible in China

The second academic steering committee and international advisory board meeting of the INTERACT4 (Intensive Blood Pressure Reduction in Acute Cerebral Haemorrhage Trial 4), jointly sponsored by the George Institute for Global Health (China), Shanghai East Hospital of Tongji University and the First Affiliated Hospital of Chengdu Medical College, was held online recently. In addition to updating progress on the study, the meeting announced the validity of early data which demonstrates the feasibility of INTERACT4 in China.

Principal investigators of the project are Prof. Craig Anderson and Dr. Lily Song from the George Institute China, Prof. Li Gang from the Stroke Centre of Shanghai East Hospital of Tongji University, and Prof. Yang Jie from the Department of Neurology of the First Affiliated Hospital of Chengdu Medical College, and an international advisory board consistes of internationally renowned stroke experts such as Professors Philip Bath, Gary Ford and Tom Robinson form the UK joined the meeting.  

Prof. Craig Anderson firstly reported the main results of the recent second Data Safety Monitoring Board (DSMB) meeting conducted a staged evaluation of the data from the first 168 recruited patients.  There was a good systolic blood pressure difference (20 mmHg) between the early intensive BP lowering and the standard BP management groups in 30 minutes. After reviewing the safety data, the DSMB recommended that the project proceed as planned and concluded that this potential life-saving program to initiate pre-hospital blood pressure lowering for patients with acute stroke in the emergency vehicle is feasible in China.

Professor Craig Anderson said: "In clinical practice, it is important to reduce the time of the initial treatment of patients with acute stroke. Early blood pressure lowering is even more important for patients with cerebral haemorrhage, for it can explicitly improve their functional prognosis. Considering that China has the highest burden of stroke, it is of particular importance that research such as INTERACT4 is undertaken."

An update on the establishment of INTERACT4 study centres and patient recruitment status were also presented. Since the launch of the first study centre in early 2020, a total of 30 centres have been officially initiated, mainly in Shanghai and Chengdu. Meanwhile, another 55 study centres from 9 provinces across China are in various stages of initiation and start up. Currently, a total of 1,464 patients have been screened in the study, of whom 410 have been successfully enrolled, that is for an enrolment rate of 28%.

According to Dr. Lily Song, Senior Researcher and Head of  Stroke Program at the George Institute China, INTERACT4 was launched in China in early 2020 and was soon affected by COVID-19, which caused delays in the early implementation. Even so, the outlook remains optimistic: "With the joint efforts of the project team and researchers, the project is progressing well. From Shanghai and Chengdu, INTERACT4's future studies will be scaled up to nine provinces across China. We are confident to complete the study goal of enrolling 3,116 patients by the end of May 2023 as planned."