CF STORM trial extends recruitment window as recent evidence shows promise for reducing treatment burden

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Finding ways to reduce and simplify treatment burden has been chosen by the CF community as a top research priority. Research studies are underway to find out if it is safe to reduce or remove muco-active treatments for people with CF who are taking Kaftrio. One of these studies is the CF STORM study in the UK and another is the SIMPLIFY study in the US. As the results of SIMPLFY have just been announced, we explain why these studies are so important, and how you can take part in CF STORM. 

CF Storm logo

Why are these trials needed? 

Life with CF can require managing many treatments and activities as part of daily care. Finding ways to reduce and simplify treatment burden has been highlighted by the CF community as a top research priority, and so studies like CF STORM are looking at just that. In the era of highly effective CFTR modulators like Kaftrio, it is important that other routine treatments are evaluated to find out if they are still necessary or beneficial for people taking Kaftrio. 

Hypertonic saline and dornase alfa (also known as DNase) are inhaled muco-active therapies which help to clear mucus from the airways in people with CF. The SIMPLIFY and CF STORM studies are looking at whether it is safe to stop taking them, and whether there is any additional benefit to continuing these treatments while taking Kaftrio.

The SIMPLIFY study followed people with CF with very good lung function over six weeks and the CF STORM study is following people with a range of lung functions over 12 months. The results of the SIMPLIFY study were announced at the recent North American CF Conference. 

What did the SIMPLFY results show? 

SIMPLIFY took place in the United States and enrolled people with CF aged 12 and above, who were already established on Kaftrio. Participants were then randomly allocated into one of two trials, to either continue or stop taking hypertonic saline, or to continue or stop taking DNase. It showed that there was no difference in lung function six weeks after stopping either DNase or hypertonic saline, for people who had relatively good lung function (average FEV1 of 97% predicted) and were established on Kaftrio. A summary of the results can be found on the Cystic Fibrosis Foundation website and the full details are published in the journal Lancet Respiratory Medicine.  

As people with CF become established on new modulator therapies like Kaftrio, it is important they have good information to decide whether to continue or stop other therapies, like dornase alfa. The SIMPLIFY study results will be important in informing that journey, and encourage us that CF STORM is both an important and appropriate study to be undertaking.

Prof. Kevin Southern, co-principal investigator for CF STORM 

Why is the CF STORM study still important, and how can I take part? 

“SIMPLIFY represents a milestone in finding out whether some treatments may be able to be safely stopped once people are established on Kaftrio. Most people taking part in SIMPLIFY had very good lung function, and the study was conducted over a relatively short period of time," said Dr Gwyneth Davies, co-principal investigator for CF STORM. 

“We don’t know whether the results would be the same for the wider CF population with different lung health, over a longer time, and that’s what the CF STORM study will tell us."

CF STORM is hoping to enrol over 750 people with CF onto the study, and is still looking for participants – so it’s not too late to take part. 

If you are aged 12 years or older, are taking Kaftrio and taking either nebulised hypertonic saline, DNase, or both, please speak to your CF team about taking part in CF STORM. As part of the trial, you may be asked to continue your daily nebulised muco-active therapy as normal, or to stop taking them for up to 12 months. 

Dr Davies added: “If you are interested in joining CF STORM, please talk to your clinical team. If you are already taking part, thank you! The sooner we can reach our trial enrolment target, the sooner we can provide answers for the benefit of the UK and global CF community!” 

Visit the CF STORM website for more information and videos about what’s involved in taking part. You can also find out more about the study on our CF Trials Tracker, where you can get in touch with the study team directly and enquire about participating. 


Let’s get to a life unlimited for everyone with CF – faster.

Our goal is a day where there are effective treatments for everyone with CF. We need life-changing treatments, treatments that minimise harmful impacts like hearing loss, treatments that work for every person with CF – and we need them now. But we can’t get there without your support.

There are lots of ways you can support us this festive season, from playing our raffle through to doing some festive fundraising or buying Christmas cards and gifts for a loved one from our online shop.  

Will you unite with us and the entire CF community this festive season so we can keep funding our vital work? 

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