An interventional study of 12 hours ETI pause and 36 hours ETI pause in Cystic Fibrosis (CF) and CFTR Gene Mutation, sponsored by University of Aarhus. Recruiting at 1 site in Denmark. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2025-02-19.
Sponsored by University of Aarhus · Not applicable, Interventional, and Diagnostic
In cystic fibrosis (CF) renal base excretion is impaired, due to mutations in the Cystic Fibrosis Transmembrane Regulator (CFTR) gene, since CFTR function is crucial in regulation of the kidney's HCO3- excretion.
The investigators suggest that challenged urine HCO3- excretion is a biomarker of CFTR function, which can be used to evaluate the extent of CFTR dysfunction and the possible correcting effects of CFTR modulating therapy.
This study aims to evaluate changes in challenged urine HCO3- excretion in CF patients, who are currently in treatment with the triple CFTR modulator combination therapy, Elexacaftor/tezacaftor/ivacaftor (ETI), before, during, and after a short treatment pause.
1,581 studies on the registry are indexed under Cystic Fibrosis; 190 are open to participants now.
This study's planned enrollment of 30 is below the median of 36 across 1,034 interventional studies indexed under Cystic Fibrosis.
Browse Cystic Fibrosis studies →University of Aarhus is the lead sponsor of 1,274 studies on the registry; 183 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Exclusion Criteria:
Other: 12 hours ETI pause
Other: 36 hours ETI pause
Other: 60 hours ETI pause
Patients with CF are randomly allocated to ETI pause lasting 12 hours.
Patients with CF are randomly allocated to ETI pause lasting either 36 hours.
Patients with CF are randomly allocated to ETI pause lasting either 60 hours.
Difference in cumulative urine bicarbonate excretion before, during, and after ETI pause.
Challenged urine HCO3- test: Quantification of urine bicarbonate excretion after an acute oral NaHCO3 challenge before, under, and after ETI pause.
Time frame: At baseline, after 12/36/60 hours of therapy pause and after therapy is resumed.
Link between changes in ETI plasma concentration and changes in urine bicarbonate excretion.
Venous blood sampling: ETI plasma concentration measurement. Challenged urine HCO3- test: Quantification of urine bicarbonate excretion
Time frame: At baseline, after 12/36/60 hours of therapy pause and after therapy is resumed.
Link between plasma acid-base status and urine acid-base excretion.
Venous blood sampling: Venous acid-base measurements.
Time frame: At baseline, after 12/36/60 hours of therapy pause and after therapy is resumed.
Changes in plasma concentration of ETI during the trial.
Venous blood sampling: ETI plasma concentration measurement.
Time frame: At baseline, after 12/36/60 hours of therapy pause and after therapy is resumed.
Changes in acid-base and fluid status during the trial.
Venous blood sampling: Venous acid-base and fluid measurements.
Time frame: At baseline, after 12/36/60 hours of therapy pause and after therapy is resumed.
Changes in electrolytes during the trial.
Venous blood sampling: Venous electrolyte measurements. Challenged HCO3- urine test: Urine electrolyte measurements.
Time frame: At baseline, after 12/36/60 hours of therapy pause and after therapy is resumed.
Plan to share: No
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University of Aarhus