['cystic fibrosis']
['glpg2737', 'placebo']

        Inclusion Criteria:

          -  Male or female subject ≥18 years of age on the day of signing the ICF.

          -  A confirmed clinical diagnosis of CF and homozygous for the F508del CFTR mutation.

          -  Stable intake of physician prescribed Orkambi (lumacaftor 400 mg/ivacaftor 250 mg
             b.i.d.) for at least 12 weeks prior to the first study drug administration, and
             planned continuation of Orkambi for the duration of the study.

          -  FEV1 ≥40% of predicted normal for age, gender and height at screening (pre- or
             postbronchodilator).

          -  Sweat chloride concentration ≥60 mmol/L at screening.

        Exclusion Criteria:

          -  History of serious allergic reaction to any drug as determined by the investigator
             (e.g., anaphylaxis requiring hospitalization) and/or known sensitivity to any
             component of the study drug.

          -  History of clinically meaningful unstable or uncontrolled chronic disease that makes
             the subject unsuitable for inclusion in the study in the opinion of the investigator.

          -  Unstable pulmonary status or respiratory tract infection (including rhinosinusitis)
             requiring a change in therapy within 4 weeks prior to the first study drug
             administration.

          -  History of hepatic cirrhosis with portal hypertension (e.g.,signs/symptoms of
             splenomegaly, esophageal varices, etc.).

          -  Abnormal liver function test at screening, defined as aspartate aminotransferase (AST)
             and/or alanine aminotransferase (ALT) and/or alkaline phosphatase and/or gammaglutamyl
             transferase (GGT) ≥3 x the upper limit of normal (ULN), and/or total bilirubin ≥1.5 x
             the ULN at screening.
      