A new, observational study will analyze the sinonasal microbial communities and inflammatory profiles of people with cystic fibrosis (CF) treated with cystic fibrosis transmembrane conductance regulator (CFTR) modulator therapy.

The study, set to begin by December 1, 2023, is not yet recruiting.

The researchers are looking to characterize the impact of CFTR modulators on bacterial communities in paranasal sinuses, the level of inflammation in the sinuses and olfactory cleft, as well as the impact of therapy on the sense of smell, sinonasal disease burden, and disease-specific and general quality of life in people with CF.

The study will enroll approximately 30 adult English-speaking participants diagnosed with CF based on genetic testing, clinical assessment, and/or sweat chloride testing and followed at the New Hampshire Cystic Fibrosis Center.

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Study participants will be asked to undergo nasal endoscopy with microbiome swab and mucus collection, take part in tests used to evaluate their sense of smell, and complete 4 surveys evaluating their quality of life and sense of smell at baseline and every 6 months over the course of 2 years.

The researchers will then assess the difference in microbial communities found in mucus swabs as well as in microbiome swab cytokine assay results between patients with CF who are currently receiving CFTR modulators and those who are not given the same treatment as primary outcome measures.

The secondary outcome measures include the difference in Sniffin’ Sticks test scores, the University of Pennsylvania Smell Identification Test scores, Cystic Fibrosis Questionnaire-Revised survey responses, Sino-nasal Outcome Test-22 (SNOT-22) survey scores, Sinus Control Test survey scores, and the questionnaire of olfactory disorders scores between the cohort receiving CFTR modulators and the cohort not receiving CFTR modulators.

The study, sponsored by Dartmouth-Hitchcock Medical Center, is set to be completed by December 1, 2026.


Impact of highly effective modulator therapy on the cystic fibrosis microbiome. ClinicalTrials.gov. Published online August 9, 2023. Accessed August 20, 2023.