Date of Award


Document Type

Scholarly Project

Degree Name

Master of Physician Assistant Studies (MPAS)


Physician Assistant Studies

First Advisor

Daryl Sieg

Second Advisor

Julie Skiba


Cystic Fibrosis; Drug therapy; Cystic Fibrosis Transmembrane Conductance Regulators; Membrane transport proteins; Membrane proteins; CFTR modulator


Cystic Fibrosis (CF) is an autosomal recessive disorder that shortens one’s life due to its effect on the cystic fibrosis transmembrane regulator (CFTR) gene. CFTR modulator medications can correct the CFTR gene and consist of a potentiator (ivacaftor), and corrector (lumacaftor, tezacaftor and elexacaftor). This research and literature review sought to evaluate if lung function improved in an individual with genetically confirmed CF after being started on CFTR modulator medications. To complete the review, six databases were searched which included: CINAHL, PubMed, Clinical Key, Cochrane Library, Embase and Dynamed Plus. Both keyword and mesh terms were used to define a set of the literature discussing CF and CFTR modulator use. A total of 24 studies were included and met the inclusion criteria of: peer reviewed, published within the past six years, had more than 20 study participants, and were not limited case reports. Phase 2 studies were included for triple therapy with elexacaftor-tezacaftor-ivacaftor and duo therapy with tezacaftor-ivacaftor, due to limited research in this area. The research indicated that individuals with G551D, non-G551D gating mutations, Gly-Asp-CFTR and ARG117HIS mutations, had an overall improvement in ppFEV1 after initiation of ivacaftor. Heterozygous and homozygous Phe508del, had the largest improvement in ppFEV1 with elexacaftor-tezacaftor-ivacaftor. Ivacaftor and lumacaftor-ivacaftor appear to have age dependent changes on ppFEV1. Individuals with severe lung disease appear to have a positive response to treatment, although it may be delayed.