An observational study in Cystic Fibrosis (CF), sponsored by Fondation Ildys. Recruiting at 11 sites in France. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-10-21.
Sponsored by Fondation Ildys · Observational
PERCE-MUCO is a prospective, multicentre, mixed-methods observational study investigating the perceptions, expectations and treatment-change intentions of adults with cystic fibrosis who are currently treated with elexacaftor/tezacaftor/ivacaftor (ETI) or whose treatment has been medically discontinued. The study focuses on patients' stated willingness to switch from ETI to vanzacaftor/tezacaftor/deutivacaftor (VTD), and on the factors associated with this intention, including treatment satisfaction, knowledge and expectations regarding VTD, quality of life, treatment adherence, reported adverse effects, access-related concerns and desired support from an advanced practice nurse. The quantitative component uses a study-specific questionnaire and routine-care CFQ-R 14+ and Morisky-8 data. A qualitative component consists of semi-structured interviews at the Roscoff cystic fibrosis centre.
Cystic fibrosis is a rare genetic disease for which CFTR modulator therapy has substantially changed treatment and patients' daily lives. Although elexacaftor/tezacaftor/ivacaftor (ETI) has improved respiratory outcomes and reduced exacerbations for many eligible patients, some patients experience intolerance or a suboptimal response. Vanzacaftor/tezacaftor/deutivacaftor (VTD) is a newer CFTR modulator combination, and patients' willingness to change from a familiar treatment to a new option cannot be assumed.
The primary objective is to assess the intention of adults with cystic fibrosis treated with ETI to change to VTD.
The primary outcome is the response to a single-choice question asking what the patient would do if their physician offered CTD: accept immediately, need time to think, or refuse.
Secondary objectives are to identify determinants of acceptance; assess the relationship between quality of life and intention to change; assess the relationship of adherence and reported tolerability with intention to change; describe the role and desired support of an advanced practice nurse during a possible transition; and explore psychological and logistical barriers through qualitative interviews.
The quantitative component is conducted across participating French cystic fibrosis centres. Participants complete the PERCE-MUCO questionnaire during a routine follow-up visit or planned hospital stay. The most recent routine-care CFQ-R 14+ and Morisky-8 questionnaires available near inclusion, together with selected clinical and treatment characteristics and adverse effects documented in the medical record, are collected in pseudonymised form.
The qualitative component is conducted at the Roscoff centre and uses individual semi-structured face-to-face interviews lasting approximately 30-45 minutes. Interviews are audio-recorded with the participant's agreement, transcribed verbatim and pseudonymised before thematic analysis.
The quantitative primary outcome is analysed descriptively; secondary analyses include descriptive statistics and comparisons using ANOVA or Kruskal-Wallis, and chi-square or Fisher's exact tests as appropriate.
Qualitative data are analysed thematically using a combination of deductive and inductive coding. The protocol estimates a quantitative sample of 343 participants and approximately 8-12 qualitative interviews, with interview recruitment continuing until data saturation.
1,605 studies on the registry are indexed under Cystic Fibrosis; 196 are open to participants now.
This study's planned enrollment of 343 is above the median of 85 across 489 observational studies indexed under Cystic Fibrosis.
Browse Cystic Fibrosis studies →Fondation Ildys is the lead sponsor of 17 studies on the registry; 8 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Adults with cystic fibrosis followed at participating French cystic fibrosis resource and competence centres (CRCMs), who currently receive ETI or whose treatment was medically discontinued.
The qualitative interview component is limited to eligible patients followed at the Roscoff CRCM.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Adults with cystic fibrosis who have received ETI for at least 3 months or whose ETI treatment was discontinued for medical reasons. The study observes treatment preferences and associated characteristics; it does not assign or require a change in treatment.
Intention to switch from ETI to VTD
Percentage of participants selecting each of three responses to the question: 'If your physician offered VTD tomorrow, what would your position be?' Response options: immediate acceptance; need time to think; refusal. Report proportions and 95% confidence intervals
Time frame: At completion of the PERCE-MUCO questionnaire at inclusion (single assessment).
Factors influencing willingness to switch
Descriptive proportions for knowledge of VTD and satisfaction with information received; preferred information sources; expectations; concerns about efficacy, adverse effects, replacing a satisfactory treatment and tolerability; and perceived access to treatment
Time frame: At completion of the PERCE-MUCO questionnaire at inclusion.
Association between quality of life and intention to switch
Association between CFQ-R 14+ scores, including the health-perception score specified in the protocol, and the three-category intention-to-switch outcome
Time frame: CFQ-R 14+ measurement closest to inclusion, collected from routine care
Association between treatment adherence and intention to switch
Association between Morisky-8 score and intention to switch; adherence categories are good (score 8), medium (6-7) and low (\<6).
Time frame: Morisky-8 measurement closest to inclusion, collected from routine care
Association between reported ETI tolerability and intention to switch
Comparison of intention-to-switch categories according to the presence or absence of adverse effects documented in the medical record
Time frame: Adverse effects documented in the medical record and available at inclusion
Need for support during a potential treatment transition
Percentage of participants requesting specific support during transition and descriptive summary of requested support, including support from a physician, coordinating nurse or advanced practice nurse
Time frame: At completion of the PERCE-MUCO questionnaire at inclusion
Patient perceptions and barriers identified in semi-structured interviews
Thematic analysis of interview transcripts exploring lived experience of Kaftrio, perception of therapeutic innovation, decision-making and the role of the advanced practice nurse
Time frame: One semi-structured interview of approximately 30-45 minutes during the study period.
Plan to share: Undecided
No publications or documents are linked to this record.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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