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Principal Investigator: 

Dr Damian Downey

Name of the Study:

CLEAR: A 2x2 factorial randomised open label trial to determine the clinical and cost- effectiveness of hypertonic saline (HTS 6%) and carbocisteine for airway clearance versus usual care over 52 weeks in bronchiectasis.

Why is this Study important?: 

Patients with bronchiectasis suffer from a persistent cough, daily sputum production and recurrent exacerbations. These can affect the quality of life of people living with bronchiectasis. This study is concerned with sputum production and exploring which combinations of agents (hypertonic saline (HTS) and carbocisteine) might help patients bring up their sputum more easily. These agents are currently used in clinical care but there is not enough evidence to recommend them as part of standard care.

What is the Research question/aim?: 

The study aims to find out whether HTS and/or carbocisteine can reduce the number of exacerbations suffered by people with bronchiectasis after 52 weeks of treatment. This research has the potential to impact guidelines for standard care in the future.  

What the Study involves: 

HTS is salty water that is delivered into the airways via a nebuliser, which converts it into a mist. This treatment takes ten minutes. Carbocisteine is taken as a capsule. Research has shown these agents can make it easier for patients to cough up sputum resulting in potentially fewer exacerbations and hospital admissions which could improve quality of life for people with bronchiectasis.

Patients will be recruited to this study and randomly assigned to one of four groups; HTS and standard care, carbocisteine and standard care, a combination of HTS and carbocisteine with standard care and standard care alone. Participants will have to attend 6 additional appointments as part of the study over a 2-year period with 5 in year one.

This study is being funded by the NIHR and patients will be recruited from sites across the UK.

PPI Involvement: 

Patients have been involved in the design of this trial and are also actively involved in the management.

Who can take part in the Study?:

Patients with Bronchiectasis from sites across the UK.

Contact Information:

Dr Damian Downey

Principal Investigator

Northern Ireland Clinical Research Network

Respiratory Research Office

Ground Floor

Belfast City Hospital

90 Lisburn Road



Tel: 028 950 43876



NI Clinical Research Facility,
U Floor, Belfast City Hospital,
Lisburn Road, Belfast, BT9 7AB

Tel:+44 (0)28 9504 0342

Connect to the NICRF