The aim of the study is to identify a link between the new CFTR modulators and physical activity in cystic fibrosis patients.

The triple combination of CFTR modulators (ELEXACAFTOR / TEZACAFTOR/ IVACAFTOR) has recently changed the management of cystic fibrosis.

This treatment has been shown to rapidly improve patients' respiratory function, with a gain in FEV1 at 1 month ranging from 10.4% to 13.6%. It also reduces the number of respiratory exacerbations and improves the nutritional status and quality of life of treated patients.

To date, there is limited data on the impact of these new therapies on physical activity. Few studies have investigated changes in exercise or physical activity parameters under ELEXACAFTOR / TEZACAFTOR/ IVACAFTOR.

The 6-minute walk test is a validated field test used routinely to assess the exercise capacity of patients with chronic respiratory diseases, including cystic fibrosis.

Inclusion Criteria:

• Patients aged ≥ 12 years with cystic fibrosis, heterozygous for the F508del mutation of the CFTR gene, treated with ELEXACAFTOR/ TEZACAFTOR/ IVACAFTOR.
• Patients followed in the respiratory diseases department of the Renee Sabran Hospital
• 6-minute walked test performed in the year preceding initiation of ELEXACAFTOR / TEZACAFTOR/ IVACAFTOR
• 6-minute walked test performed after treatment initiation (between the 3rd month and the 14th month)
• No opposition to participation

Exclusion Criteria:

• - Age < 12 years
• Pregnancy
• Discontinuation or reduction in dosage of ELEXACAFTOR/ TEZACAFTOR/ IVACAFTOR
• Patients objecting to the use of their data for research purposes

Cohort: cystic fibrosis patients followed in the respiratory diseases department of the Renee Sabran Hospital (approximately 100 patients)