This is a multicenter, cross-sectional, cohort study which will collect contemporary SC values from approximately 1000 CF patients prescribed and currently receiving commercially approved CFTR modulator therapies.



Eligible Ages
Over 4 Months
Eligible Genders
Accepts Healthy Volunteers

Inclusion Criteria

  • Written informed consent (and assent when applicable) obtained from subject or subject's legal representative
  • Enrolled in the CFF Patient Registry
  • Male or female ≥ 4 months of age on day of study visit
  • Documentation of a CF diagnosis as evidenced by one or more clinical features consistent with the CF phenotype and one or more of the following criteria:
  • Sweat chloride equal to or greater than 60 mEq/liter by quantitative pilocarpine iontophoresis test (QPIT)
  • Two well-characterized mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene
  • Current treatment with a prescribed commercially approved CFTR modulator for at least 3 months prior to enrollment
  • Able to perform the testing and procedures required for this study, as judged by the investigator

Exclusion Criteria

  • Presence of a condition or abnormality that, in the opinion of the Investigator, would compromise the safety of the patient or the quality of the data
  • Currently enrolled in an investigational trial (including open-label follow-on studies and EAPs) of an agent expected to have an impact on sweat chloride (refer to current list provided on study website)

Study Design

Study Type
Observational Model
Time Perspective

Recruiting Locations

Massachusetts General Hospital
Boston, Massachusetts 02114
Lauren Guthrie

More Details

Nicole Hamblett

Study Contact

Anna Mead

Detailed Description

Eligible subjects who have been prescribed and chronically taking a commercially approved CFTR modulator for at least 3 months will be enrolled for a single visit to collect sweat to be analyzed for SC at their local site laboratory. Limited clinical data obtained at this visit will be augmented by retrospective and prospective data obtained from the CFFPR. Study subjects who have been prescribed and switch to an alternative commercially approved CFTR modulator will be approached to re-enroll in the study after being on the alternative modulator for at least 3 months so that a new SC value can be obtained.


Study information shown on this site is derived from ClinicalTrials.gov (a public registry operated by the National Institutes of Health). The listing of studies provided is not certain to be all studies for which you might be eligible. Furthermore, study eligibility requirements can be difficult to understand and may change over time, so it is wise to speak with your medical care provider and individual research study teams when making decisions related to participation.