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Queen’s leading UK-wide clinical trial to examine drug effectiveness for critically ill ICU patients

A new clinical trial led by Queen’s University Belfast will investigate different drugs for helping airway clearance in critically ill patients who are on mechanical ventilators.

Researchers funded by the National Institute for Health Research (NIHR) will deliver a clinical trial aiming to recruit approximately 2,000 patients across the UK in order to determine the effectiveness of different treatments for supporting the management of patients with acute respiratory failure receiving mechanical ventilation. 

A common problem that patients receiving mechanical ventilation can experience is thick secretions in the airways, which can be difficult to clear, and make the ventilation process harder. The MARCH trial will compare different drugs for managing thick secretions. These drugs will be compared individually, as well as in combination, with standard care. Using drugs to help airway clearance may reduce the duration of time patients require mechanical ventilation. 

The two drugs under investigation (carbocisteine and hypertonic saline) are commonly used at present in intensive care units (ICU) across the UK, but it is not known which approach to their use is most effective. The comparative data produced by the trial will improve understanding of which, if either, of the drugs are most effective at improving patient outcomes. 

The opportunity to join the trial will be offered to all patients receiving mechanical ventilation in ICU and who have problems with thick secretions. ICUs across Northern Ireland, England, Scotland, and Wales will take part. The trial will provide patients with an equal chance of receiving standard care or any of the drug treatments. Which treatment the patient will receive will be decided by a computer at random and patients will receive all other treatments recommended by their clinical team. 

The trial is important for optimising the way in which patients in the ICU receiving mechanical ventilation are managed, and for reducing the delivery of potentially ineffective medications. 

Dr Bronwen Connolly, Chief Investigator for the trial from The Wellcome-Wolfson Institute for Experimental Medicine at Queen’s University said: “Investigating treatments through clinical trials is the safest and most appropriate method for determining their effect. At present we do not know whether these drugs are helpful for critically ill patients receiving mechanical ventilation. This trial offers us the opportunity to carefully test these drugs and use the knowledge we gain to improve patient care.” 

Involvement of the NIHR has been crucial to the trial; funding has been received via the Health Technology Assessment Programme, and support will be sought from the NIHR Clinical Research Network. The trial is coordinated by the Northern Ireland Clinical Trials Unit (NICTU) and is sponsored by the Belfast Health and Social Care Trust. The trial team comprises of multi-professional experts across critical care medicine, physiotherapy, pharmacy, and nursing, with world class expertise in the delivery of clinical trials to critically ill patients with acute respiratory failure. 

The research is part funded by the Health and Social Care Research & Development Division (HSC R&D Division) of the Public Health Agency through the Northern Ireland Clinical Research Network and Clinical Trials Unit. The ethos of the HSC R&D Division is based on the principle that the best health and social care must be underpinned by knowledge, based on well conducted research, which can then be applied in the delivery of care. 

Dr Janice Bailie, Assistant Director, HSC R&D Division said: “Northern Ireland researchers play a leading role in this national research work. The MARCH study has the potential to develop tailored therapies and improve outcomes for patients who are critically ill and require ventilation. Research like this will help to ensure that the best treatment is available to help patients in critical care with acute respiratory failure and help improve patient care at a very challenging time."

The MARCH trial will formally commence in February 2021. Further information can be found at


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