for people ages 4 months and up (full criteria)
at La Jolla, California and other locations
study started
estimated completion



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.

Official Title

The CHEC-SC Cohort Study: CHaractErizing CFTR Modulated Changes in Sweat Chloride and Their Association With Clinical Outcomes


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.


Cystic FibrosisCFSweatSweat chlorideCFTR ModulatorFibrosis


You can join if…

Open to people ages 4 months and up

  • 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

You CAN'T join if...

  • 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)


  • University of California San Diego accepting new patients
    La JollaCalifornia92093United States
  • Childrens Hospital Los Angeles accepting new patients
    Los AngelesCalifornia90027United States


accepting new patients
Start Date
Completion Date
Nicole Hamblett
Study Type
Last Updated