Impact of Discontinuing Dornase Alfa in People With CF on Highly Effective CFTR Modulator Therapy-A SIMPLIFY Sub-Study — SIMPLIFY-DN  

Cystic Fibrosis Clinical Trial

Official title: A Master Protocol to Test the Impact of Discontinuing Chronic Therapies in People With Cystic Fibrosis on Highly Effective CFTR Modulator Therapy - Dornase Alfa (Dnase)

Status Completed

Clinical Trial Summary

Despite the increasingly common use of cystic fibrosis transmembrane conductance regulator (CFTR) modulator therapies in treating cystic fibrosis (CF), it is still largely unknown whether or not other chronic therapies can be safely stopped. This SIMPLIFY sub-study is being done to test whether or not it is safe to stop taking dornase alfa (Dnase) in those people that are also taking elexacaftor/tezacaftor/ivacaftor (ETI).

ETI is a combination CFTR modulator therapy that was approved by the Food and Drug Administration for people with CF who have at least one F508del mutation. The three drugs that make up ETI work together to allow many more chloride ions to move into and out of the cells, improving the balance of salt and water in the lungs. These changes result in better clearance of mucus from the lungs and improvements in lung function.

Dornase alfa (Dnase) also improves clearance of mucus from the lungs to support lung function and has been available to people with CF for many years. Dnase is considered to be relatively burdensome and it is not known whether Dnase can improve or maintain lung function above what is already gained through ETI use.

The goal of this SIMPLIFY sub-study is to get information about whether or not it is safe to stop Dnase by testing if there is a change in lung function in participants with cystic fibrosis (CF) who are assigned to stop taking Dnase as compared to those who are assigned to keep taking Dnase while continuing to take ETI.

This is a sub study of master protocol SIMPLIFY-IP-19, NCT04378153.

The sub study investigating the impact of discontinuing and continuing hypertonic saline is registered under NCTXXXXXXX (will add once available).

Clinical Trial Description

This SIMPLIFY sub-study (Dornase Alfa (Dnase) Trial) is designed to evaluate the effects of discontinuing Dnase in people with cystic fibrosis (CF) age 12 and older currently taking the highly effective modulator elexacaftor/tezacaftor/ivacaftor (ETI). This is an open label two-arm randomized non-inferiority trial consisting of a 2-week screening period, randomization to continue or discontinue dornase alfa, followed by a 6-week study period. Participants at trial entry will be randomized 1:1 to either continue or discontinue their Dnase therapy.

Clinical outcomes (forced expiratory volume in 1 second [FEV1], antibiotic use, pulmonary exacerbations, and patient reported outcomes), safety (adverse events) and patient reported outcomes to evaluate respiratory symptoms and the participant's perception of how stopping Dnase would impact their daily life will be evaluated in all subjects. Additionally, a subset of participants at selected study sites will participate in Multiple Breath Washout (MBW) to evaluate changes in lung clearance index (LCI). ;

Related Conditions & MeSH terms

• Cystic Fibrosis
• Fibrosis

• NCT number: NCT06350474
• Study type: Interventional
• Source: Seattle Children's Hospital
• Status: Completed
• Phase: N/A
• Start date: August 25, 2020
• Completion date: July 11, 2022