What happens during a trial

Clinical trials take many different forms, and what you’ll be asked to do will vary greatly depending on what is being researched and the type of trial. You could be asked to take a new treatment, such as: 

• antibiotics and other treatments for infections
• new modulators
• genetic therapies
• anti-inflammatory medicines. 

Alternatively, you could be asked to: 

• change your lifestyle, such as the way you do your airway clearance (physio) 
• trial a piece of medical equipment such as an insulin pump
• stop taking a certain treatment
• trial using existing medicines in the best way. 

For some studies, you might only be asked to agree for your clinical data to be shared and/or complete a questionnaire. This may be the case if it’s an observational study.

There are many different ways that a trial team can measure the effect of a treatment, which will depend on what the treatment is. You might be asked to complete a questionnaire or interview about your views and experiences. Your trial team might ask to measure or test:

• lung function e.g. FEV1, multiple breath washout, a chest scan
• body weight
• blood sample
• urine sample
• sputum sample
• oropharyngeal or nasal swab
• sweat test
• vital signs e.g. blood pressure, electrocardiogram (ECG)

Clinical trials are now safer than ever and serious side effects are very rare. Clinical trials are carefully controlled, regulated and organised to minimise risk to participants. 

During the informed consent process, you should be told everything that the researchers know about possible risks and side effects so you can make an informed choice.

Before a trial

Before a trial is given the necessary regulatory approval to open, trial organisers must obtain authorisation from independent bodies. They will check: 

• the trial is conducted by qualified researchers and has a valid purpose
• that participants will be fully informed as to what the trial will involve
• the trial will not cause undue harm to participants.

New medications will have been checked using human and animal cells, before ever being given to humans. Find out more about trial phases.

The National Institute for Health and Care Research has created a useful series of videos about research ethics and safety.

Will I experience side effects? 

There is always a small possibility of unpleasant or potentially serious side effects of any new treatment. However, serious side effects are very rare.

You will be monitored closely throughout any trial and afterwards for the follow-up period. Trials teams will look out for any side effects and ask about any positive or negative changes you experience. The extra attention to your health during a clinical trial means that any changes, whether related to CF or to treatment, are likely to be picked up sooner than if you weren’t in a trial. 

Every trial also has an independent Data Safety Monitoring Board (DSMB). If anything happens during a trial, such as a bad reaction, it is immediately reported to the DSMB. They will stop a trial if there is any doubt about the safety of the treatment.

You can stop participating in a trial at any time, without giving a reason. This will not affect your care in any way.

If you move during a trial, you can ask if there is another CF centre nearby that are also running the trial. The trial team might also be able to fund your travel to a centre for the remaining trial visits. 

A trial may run at several CF centres across the UK, Europe or worldwide, or might be taking place at one CF centre only. You might have to travel to a different CF centre to take part in a trial. Some trials may be able to reimburse you for travel and accommodation costs if you have to travel a long way.

Some trials have in-person visits but others may be partially or fully virtual, with telephone ‘visits’ or remote monitoring devices like smartwatches or apps.

Although trials can run for many months, or even years, it doesn’t mean that you would be expected to participate for this long. New treatments need extra monitoring and follow-up to find the long-term effects. 

If the trial is running at your own CF centre, appointments may be scheduled with your routine clinic appointments. You may have to go the CF centre more often than you would usually. 

This varies from trial to trial. Many trial teams can give you money for expenses such as travel to the CF centre and food during a trial visit. Ask the trial team what they can offer. 

Yes. If you agree to take part in a clinical trial, any information that is collected about you by the people conducting the trial will be kept confidential. The people running the trial cannot tell anyone outside of your healthcare and research team that you are taking part in the trial without asking you first.

Once the trial has finished, the results may be published in a scientific journal or at a conference but no patient-level data or information that can identify you will be shared.

When you come to end of taking part in a clinical trial, you may have a lot of questions about what happens next – for example, whether you can stay on the treatment and when you’ll hear about results.

Find out what happens when you finish a trial