Advertisement
Review Article| Volume 43, ISSUE 4, P617-630, December 2022

Novel Applications of Biomarkers and Personalized Medicine in Cystic Fibrosis

  • Jennifer S. Guimbellot
    Affiliations
    Department of Pediatrics, Division of Pulmonary and Sleep Medicine, Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham; 1600 7th Avenue South, ACC 620, Birmingham, AL 35233, USA
    Search for articles by this author
  • David P. Nichols
    Affiliations
    Department of Pediatrics, Division of Pulmonary Medicine, Seattle Children’s Hospital, University of Washington School of Medicine, Building Cure, 1920 Terry Avenue, Office 4-209, Seattle, WA 98109, USA
    Search for articles by this author
  • John J. Brewington
    Correspondence
    Corresponding author. Division of Pulmonary Medicine, Cincinnati Children’s Hospital Medical Center, 3333 Burnet Avenue, MLC 2021, Cincinnati, OH 45229.
    Affiliations
    Department of Pediatrics, University of Cincinnati College of Medicine, 3230 Eden Avenue, Cincinnati, OH 45267, USA

    Division of Pulmonary Medicine, Cincinnati Children’s Hospital Medical Center, 3333 Burnet Avenue, MLC 2021, Cincinnati, OH 45229, USA
    Search for articles by this author

      Keywords

      To read this article in full you will need to make a payment

      Purchase one-time access:

      Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online access
      One-time access price info
      • For academic or personal research use, select 'Academic and Personal'
      • For corporate R&D use, select 'Corporate R&D Professionals'

      Subscribers receive full online access to your subscription and archive of back issues up to and including 2002.

      Content published before 2002 is available via pay-per-view purchase only.

      Subscribe:

      Subscribe to Clinics in Chest Medicine
      Already a print subscriber? Claim online access
      Already an online subscriber? Sign in
      Institutional Access: Sign in to ScienceDirect

      References

        • Accurso F.J.
        • Rowe S.M.
        • Clancy J.P.
        • et al.
        Effect of VX-770 in persons with cystic fibrosis and the G551D-CFTR mutation.
        N Engl J Med. 2010; 363: 1991-2003
        • Heijerman H.G.M.
        • McKone E.F.
        • Downey D.G.
        • et al.
        Efficacy and safety of the elexacaftor plus tezacaftor plus ivacaftor combination regimen in people with cystic fibrosis homozygous for the F508del mutation: a double-blind, randomised, phase 3 trial.
        Lancet, London, England)2019
        • Middleton P.G.
        • Mall M.A.
        • Drevinek P.
        • et al.
        Elexacaftor-Tezacaftor-Ivacaftor for Cystic Fibrosis with a Single Phe508del Allele.
        N Engl J Med. 2019; 381: 1809-1819
        • Ramsey B.W.
        • Davies J.
        • McElvaney N.G.
        • et al.
        A CFTR potentiator in patients with cystic fibrosis and the G551D mutation.
        N Engl J Med. 2011; 365: 1663-1672
        • Rowe S.M.
        • Daines C.
        • Ringshausen F.C.
        • et al.
        Tezacaftor-ivacaftor in residual-function heterozygotes with cystic fibrosis.
        N Engl J Med. 2017; 377: 2024-2035
        • Wainwright C.E.
        • Elborn J.S.
        • Ramsey B.W.
        • et al.
        Lumacaftor-Ivacaftor in Patients with Cystic Fibrosis Homozygous for Phe508del CFTR.
        N Engl J Med. 2015; 373: 220-231
        • McGarry M.E.
        • McColley S.A.
        Cystic fibrosis patients of minority race and ethnicity less likely eligible for CFTR modulators based on CFTR genotype.
        Pediatr Pulmonol. 2021; 56: 1496-1503
        • DiMango E.
        • Simpson K.
        • Menten E.
        • et al.
        Health Disparities among adults cared for at an urban cystic fibrosis program.
        Orphanet J rare Dis. 2021; 16: 332
        • Quittner A.L.
        • Schechter M.S.
        • Rasouliyan L.
        • et al.
        Impact of socioeconomic status, race, and ethnicity on quality of life in patients with cystic fibrosis in the United States.
        Chest. 2010; 137: 642-650
        • Hanafin P.O.
        • Sermet-Gaudelus I.
        • Griese M.
        • et al.
        Insights into patient variability during ivacaftor-lumacaftor therapy in cystic fibrosis.
        Front Pharmacol. 2021; 12: 577263
        • van der Meer R.
        • Wilms E.B.
        • Heijerman H.G.M.
        CFTR modulators: does one dose fit all?.
        J Personalized Med. 2021; 11
        • Guimbellot J.S.
        • Ryan K.J.
        • Anderson J.D.
        • et al.
        Variable cellular ivacaftor concentrations in people with cystic fibrosis on modulator therapy.
        J Cystic Fibrosis. 2020; 19: 742-745
        • Sheppard D.N.
        • Carson M.R.
        • Ostedgaard L.S.
        • et al.
        Expression of cystic fibrosis transmembrane conductance regulator in a model epithelium.
        Am J Physiol. 1994; 266: L405-L413
        • Dekkers J.F.
        • Wiegerinck C.L.
        • de Jonge H.R.
        • et al.
        A functional CFTR assay using primary cystic fibrosis intestinal organoids.
        Nat Med. 2013; 19: 939-945
        • Ramalho A.S.
        • Furstova E.
        • Vonk A.M.
        • et al.
        Correction of CFTR function in intestinal organoids to guide treatment of Cystic Fibrosis.
        Eur Respir J. 2020; 57: 1902426
        • Geurts M.H.
        • de Poel E.
        • Amatngalim G.D.
        • et al.
        CRISPR-based adenine editors correct nonsense mutations in a cystic fibrosis organoid biobank.
        Cell stem cell. 2020; 26: 503-510
        • de Winter-de Groot K.M.
        • Janssens H.M.
        • van Uum R.T.
        • et al.
        Stratifying infants with cystic fibrosis for disease severity using intestinal organoid swelling as a biomarker of CFTR function.
        Eur Respir J. 2018; 52
        • Noordhoek J.
        • Gulmans V.
        • van der Ent K.
        • et al.
        Intestinal organoids and personalized medicine in cystic fibrosis: a successful patient-oriented research collaboration.
        Curr Opin Pulm Med. 2016; 22: 610-616
        • Beekman J.M.
        Individualized medicine using intestinal responses to CFTR potentiators and correctors.
        Pediatr Pulmonol. 2016; 51: S23-S34
        • Dekkers R.
        • Vijftigschild L.A.
        • Vonk A.M.
        • et al.
        A bioassay using intestinal organoids to measure CFTR modulators in human plasma.
        J Cystic Fibrosis. 2015; 14: 178-181
        • de Poel E.
        • Spelier S.
        • Suen S.W.F.
        • et al.
        Functional restoration of CFTR nonsense mutations in intestinal organoids.
        J Cyst Fibro. 2021; 21: 246-253
        • de Poel E.
        • Spelier S.
        • Korporaal R.
        • et al.
        CFTR rescue in intestinal organoids with GLPG/ABBV-2737, ABBV/GLPG-2222 and ABBV/GLPG-2451 triple therapy.
        Front Mol Biosci. 2021; 8: 698358
        • Graeber S.Y.
        • van Mourik P.
        • Vonk A.M.
        • et al.
        Comparison of organoid swelling and in vivo biomarkers of CFTR function to determine effects of lumacaftor-ivacaftor in patients with cystic fibrosis homozygous for the F508del mutation.
        Am J Respir Crit Care Med. 2020; 202: 1589-1592
        • Neuberger T.
        • Burton B.
        • Clark H.
        • et al.
        Use of primary cultures of human bronchial epithelial cells isolated from cystic fibrosis patients for the pre-clinical testing of CFTR modulators.
        Methods Mol Biol (Clifton, NJ). 2011; 741: 39-54
        • Brewington J.J.
        • Filbrandt E.T.
        • LaRosa 3rd, F.J.
        • et al.
        Brushed nasal epithelial cells are a surrogate for bronchial epithelial CFTR studies.
        JCI Insight. 2018; 3
        • Stokes A.B.
        • Kieninger E.
        • Schogler A.
        • et al.
        Comparison of three different brushing techniques to isolate and culture primary nasal epithelial cells from human subjects.
        Exp Lung Res. 2014; 40: 327-332
        • Muller L.
        • Brighton L.E.
        • Carson J.L.
        • et al.
        Culturing of human nasal epithelial cells at the air liquid interface.
        J Vis Exp. 2013; 80
        • de Courcey F.
        • Zholos A.V.
        • Atherton-Watson H.
        • et al.
        Development of primary human nasal epithelial cell cultures for the study of cystic fibrosis pathophysiology.
        Am J Physiol Cell Physiol. 2012; 303: C1173-C1179
        • Mosler K.
        • Coraux C.
        • Fragaki K.
        • et al.
        Feasibility of nasal epithelial brushing for the study of airway epithelial functions in CF infants.
        J Cystic Fibros. 2008; 7: 44-53
        • Palechor-Ceron N.
        • Suprynowicz F.A.
        • Upadhyay G.
        • et al.
        Radiation induces diffusible feeder cell factor(s) that cooperate with ROCK inhibitor to conditionally reprogram and immortalize epithelial cells.
        Am J Pathol. 2013; 183: 1862-1870
        • Liu X.
        • Ory V.
        • Chapman S.
        • et al.
        ROCK inhibitor and feeder cells induce the conditional reprogramming of epithelial cells.
        Am J Pathol. 2012; 180: 599-607
        • Brewington J.J.
        • Filbrandt E.T.
        • LaRosa 3rd, F.J.
        • et al.
        Detection of CFTR function and modulation in primary human nasal cell spheroids.
        J Cyst Fibros. 2017; 17: 26-33
        • Anderson J.D.
        • Liu Z.
        • Odom L.V.
        • et al.
        CFTR function and clinical response to modulators parallel nasal epithelial organoid swelling.
        Am J Physiol Lung Cell Mol Physiol. 2021; 321: L119-L129
        • Liu Z.
        • Anderson J.D.
        • Deng L.
        • et al.
        Human nasal epithelial organoids for therapeutic development in cystic fibrosis.
        Genes (Basel). 2020; 11: 603
        • Guimbellot J.S.
        • Leach J.M.
        • Chaudhry I.G.
        • et al.
        Nasospheroids permit measurements of CFTR-dependent fluid transport.
        JCI insight. 2017; 2: e95734
        • McGarry M.E.
        • Illek B.
        • Ly N.P.
        • et al.
        In vivo and in vitro ivacaftor response in cystic fibrosis patients with residual CFTR function: N-of-1 studies.
        Pediatr Pulmonol. 2017; 52: 472-479
        • Ahmadi S.
        • Bozoky Z.
        • Di Paola M.
        • et al.
        Phenotypic profiling of CFTR modulators in patient-derived respiratory epithelia.
        NPJ Genomic Med. 2017; 2: 12
        • Pranke I.
        • Hatton A.
        • Masson A.
        • et al.
        Might brushed nasal cells Be a surrogate for CFTR modulator clinical response?.
        Am J Respir Crit Care Med. 2019; 199: 123-126
        • Pranke I.M.
        • Hatton A.
        • Simonin J.
        • et al.
        Correction of CFTR function in nasal epithelial cells from cystic fibrosis patients predicts improvement of respiratory function by CFTR modulators.
        Scientific Rep. 2017; 7: 7375
        • McCarthy C.
        • Brewington J.J.
        • Harkness B.
        • et al.
        Personalised CFTR pharmacotherapeutic response testing and therapy of cystic fibrosis.
        Eur Respir J. 2018; 51: 1702457
        • Jordan C.L.
        • Noah T.L.
        • Henry M.M.
        Therapeutic challenges posed by critical drug-drug interactions in cystic fibrosis.
        Pediatr Pulmonol. 2016; 51: S61-S70
        • Dalboge C.S.
        • Nielsen X.C.
        • Dalhoff K.
        • et al.
        Pharmacokinetic variability of clarithromycin and differences in CYP3A4 activity in patients with cystic fibrosis.
        J Cystic Fibros. 2014; 13: 179-185
        • Schultz A.N.
        • Hoiby N.
        • Nielsen X.C.
        • et al.
        Individual pharmacokinetic variation leads to underdosing of ciprofloxacin in some cystic fibrosis patients.
        Pediatr Pulmonol. 2017; 52: 319-323
        • Rey E.
        • Treluyer J.M.
        • Pons G.
        Drug disposition in cystic fibrosis.
        Clin Pharmacokinet. 1998; 35: 313-329
        • Castagnola E.
        • Cangemi G.
        • Mesini A.
        • et al.
        Pharmacokinetics and pharmacodynamics of antibiotics in cystic fibrosis: a narrative review.
        Int J Antimicrob Agents. 2021; 58: 106381
        • Walker S.
        • Habib S.
        • Rose M.
        • et al.
        Clinical use and bioavailability of tacrolimus in heart-lung and double lung transplant recipients with cystic fibrosis.
        Transplant Proc. 1998; 30: 1519-1520
        • Huttner A.
        • Harbarth S.
        • Hope W.W.
        • et al.
        Therapeutic drug monitoring of the beta-lactam antibiotics: what is the evidence and which patients should we be using it for?.
        J Antimicrob Chemother. 2015; 70: 3178-3183
        • Drennan P.G.
        • Thoma Y.
        • Barry L.
        • et al.
        Bayesian forecasting for intravenous tobramycin dosing in adults with cystic fibrosis using one versus two serum concentrations in a dosing interval.
        Ther Drug Monit. 2021; 43: 505-511
        • McDade E.J.
        • Hewlett J.L.
        • Moonnumakal S.P.
        • et al.
        Evaluation of vancomycin dosing in pediatric cystic fibrosis patients.
        J Pediatr Pharmacol Ther. 2016; 21: 155-161
        • Sherwin C.M.
        • Zobell J.T.
        • Stockmann C.
        • et al.
        Pharmacokinetic and pharmacodynamic optimisation of intravenous tobramycin dosing among children with cystic fibrosis.
        J Pharmacokinet Pharmacodyn. 2014; 41: 71-79
        • Di Paolo M.
        • Hewitt L.
        • Nwanko E.
        • et al.
        A retrospective 'real-world' cohort study of azole therapeutic drug monitoring and evolution of antifungal resistance in cystic fibrosis.
        JAC Antimicrob Resist. 2021; 3: dlab026
        • Gothe F.
        • Schmautz A.
        • Hausler K.
        • et al.
        Treating allergic bronchopulmonary aspergillosis with short-term prednisone and itraconazole in cystic fibrosis.
        J Allergy Clin Immunol Pract. 2020; 8: 2608-2614 e2603
        • Bentley S.
        • Davies J.C.
        • Gastine S.
        • et al.
        Clinical pharmacokinetics and dose recommendations for posaconazole gastroresistant tablets in children with cystic fibrosis.
        J Antimicrob Chemother. 2021; 76: 3247-3254
        • Martiniano S.L.
        • Wagner B.D.
        • Brennan L.
        • et al.
        Pharmacokinetics of oral antimycobacterials and dosing guidance for Mycobacterium avium complex treatment in cystic fibrosis.
        J Cyst Fibros. 2021; 20: 772-778
        • Cameron L.H.
        • Peloquin C.A.
        • Hiatt P.
        • et al.
        Administration and monitoring of clofazimine for NTM infections in children with and without cystic fibrosis.
        J Cyst Fibros. 2021; 21: 348-352
        • Guimbellot J.S.
        • Acosta E.P.
        • Rowe S.M.
        Sensitivity of ivacaftor to drug-drug interactions with rifampin, a cytochrome P450 3A4 inducer.
        Pediatr Pulmonol. 2018; 53: E6-E8
        • Knapp E.A.
        • Fink A.K.
        • Goss C.H.
        • et al.
        The cystic fibrosis foundation patient registry. design and methods of a national observational disease registry.
        Ann Am Thorac Soc. 2016; 13: 1173-1179
        • Konstan M.W.
        • VanDevanter D.R.
        • Sawicki G.S.
        • et al.
        Association of high-dose ibuprofen use, lung function decline, and long-term survival in children with cystic fibrosis.
        Ann Am Thorac Soc. 2018; 15: 485-493
        • Lands L.C.
        • Stanojevic S.
        Oral non-steroidal anti-inflammatory drug therapy for lung disease in cystic fibrosis.
        Cochrane database Syst Rev. 2019; 9: CD001505
        • Bruch B.A.
        • Singh S.B.
        • Ramsey L.J.
        • et al.
        Impact of a cystic fibrosis transmembrane conductance regulator (CFTR) modulator on high-dose ibuprofen therapy in pediatric cystic fibrosis patients.
        Pediatr Pulmonol. 2018; 53: 1035-1039
        • Habler K.
        • Kalla A.S.
        • Rychlik M.
        • et al.
        Isotope dilution LC-MS/MS quantification of the cystic fibrosis transmembrane conductance regulator (CFTR) modulators ivacaftor, lumacaftor, tezacaftor, elexacaftor, and their major metabolites in human serum.
        Clin Chem Lab Med. 2021; 60: 82-91
        • Schneider E.K.
        • Reyes-Ortega F.
        • Wilson J.W.
        • et al.
        Development of HPLC and LC-MS/MS methods for the analysis of ivacaftor, its major metabolites and lumacaftor in plasma and sputum of cystic fibrosis patients treated with ORKAMBI or KALYDECO.
        J Chromatogr B Analyt Technol Biomed Life Sci. 2016; 1038: 57-62
        • Reyes-Ortega F.
        • Qiu F.
        • Schneider-Futschik E.K.
        Multiple reaction monitoring mass spectrometry for the drug monitoring of ivacaftor, tezacaftor, and elexacaftor treatment response in cystic fibrosis: a high-throughput method.
        ACS Pharmacol Transl Sci. 2020; 3: 987-996
        • Administration FaD
        Drug approval package: trikafta.
        (Available at:) (Accessed July 30, 2020)
        • Administration FaD
        Drug approval package: kalydeco (ivacaftor).
        (Available at:) (Accessed February 12, 2019)
        • Guhr Lee T.N.
        • Cholon D.M.
        • Quinney N.L.
        • et al.
        Accumulation and persistence of ivacaftor in airway epithelia with prolonged treatment.
        J Cyst Fibros. 2020; 19: 746-751
        • Van Goor F.
        • Hadida S.
        • Grootenhuis P.D.
        • et al.
        Rescue of CF airway epithelial cell function in vitro by a CFTR potentiator, VX-770.
        Proc Natl Acad Sci U S A. 2009; 106: 18825-18830
        • Cholon D.M.
        • Quinney N.L.
        • Fulcher M.L.
        • et al.
        Potentiator ivacaftor abrogates pharmacological correction of DeltaF508 CFTR in cystic fibrosis.
        Sci translational Med. 2014; 6 (246ra296)
        • Avramescu R.G.
        • Kai Y.
        • Xu H.
        • et al.
        Mutation-specific downregulation of CFTR2 variants by gating potentiators.
        Hum Mol Genet. 2017; 26: 4873-4885
        • Jeyaratnam J.
        • van der Meer R.
        • Berkers G.
        • et al.
        Breast development in a 7 year old girl with CF treated with ivacaftor: an indication for personalized dosing?.
        J Cyst Fibros. 2021; 20: e63-e66
        • Stylemans D.
        • Francois S.
        • Vincken S.
        • et al.
        A case of self-limited drug induced liver injury under treatment with elexacaftor/tezacaftor/ivacaftor: when it is worth taking the risk.
        J Cyst Fibros. 2021; 20: 712-714
        • Lowry S.
        • Mogayzel P.J.
        • Oshima K.
        • et al.
        Drug-induced liver injury from elexacaftor/ivacaftor/tezacaftor.
        J Cyst Fibros. 2021; 21: e99-e101
        • Phan H.
        Treatment complexity in cystic fibrosis (CF): an increasing multifaceted challenge.
        Pediatr Pulmonol. 2018; 53: 1174-1176
        • Smith M.
        • Ryan K.J.
        • Gutierrez H.
        • et al.
        Ivacaftor-elexacaftor-tezacaftor and tacrolimus combination in cystic fibrosis.
        J Cyst Fibros. 2021; 21: e8-e10
        • McKinzie C.J.
        • Doligalski C.T.
        • Lobritto S.J.
        • et al.
        Use of elexacaftor/tezacaftor/ivacaftor in liver transplant patients with cystic fibrosis.
        J Cyst Fibros. 2021; 21: 227-229
        • Chouchane I.
        • Stremler-Lebel N.
        • Reix P.
        Lumacaftor/ivacaftor initiation in two liver transplantation patients under tacrolimus and antifungal azoles.
        Clin Case Rep. 2019; 7: 616-618
        • Qiu F.
        • Habgood M.D.
        • Huang Y.
        • et al.
        Entry of cystic fibrosis transmembrane conductance potentiator ivacaftor into the developing brain and lung.
        J Cyst Fibros. 2021; 20: 857-864
        • Taylor-Cousar J.L.
        • Jain R.
        Maternal and fetal outcomes following elexacaftor-tezacaftor-ivacaftor use during pregnancy and lactation.
        J Cyst Fibros. 2021; 20: 402-406
        • Wilk M.A.
        • Braun A.T.
        • Farrell P.M.
        • et al.
        Applying whole-genome sequencing in relation to phenotype and outcomes in siblings with cystic fibrosis.
        Cold Spring Harb Mol Case Stud. 2020; 6
        • Carter S.C.
        • McKone E.F.
        Pharmacogenetics of cystic fibrosis treatment.
        Pharmacogenomics. 2016; 17: 1453-1463
        • Relling M.V.
        • Klein T.E.
        • Gammal R.S.
        • et al.
        The clinical pharmacogenetics implementation consortium: 10 Years later.
        Clin Pharmacol Ther. 2020; 107: 171-175
        • Provenzani A.
        • Santeusanio A.
        • Mathis E.
        • et al.
        Pharmacogenetic considerations for optimizing tacrolimus dosing in liver and kidney transplant patients.
        World J Gastroenterol. 2013; 19: 9156-9173
        • Shuker N.
        • Bouamar R.
        • van Schaik R.H.
        • et al.
        A randomized controlled trial comparing the efficacy of cyp3a5 genotype-based with body-weight-based tacrolimus dosing after living donor kidney transplantation.
        Am J Transplant. 2016; 16: 2085-2096
        • Pallet N.
        • Etienne I.
        • Buchler M.
        • et al.
        Long-term clinical impact of adaptation of initial tacrolimus dosing to CYP3A5 genotype.
        Am J Transplant. 2016; 16: 2670-2675
        • Aouam K.
        • Kolsi A.
        • Kerkeni E.
        • et al.
        Influence of combined CYP3A4 and CYP3A5 single-nucleotide polymorphisms on tacrolimus exposure in kidney transplant recipients: a study according to the post-transplant phase.
        Pharmacogenomics. 2015; 16: 2045-2054
        • Elens L.
        • Bouamar R.
        • Hesselink D.A.
        • et al.
        A new functional CYP3A4 intron 6 polymorphism significantly affects tacrolimus pharmacokinetics in kidney transplant recipients.
        Clin Chem. 2011; 57: 1574-1583
        • Elens L.
        • Hesselink D.A.
        • van Schaik R.H.
        • et al.
        The CYP3A422 allele affects the predictive value of a pharmacogenetic algorithm predicting tacrolimus predose concentrations.
        Br J Clin Pharmacol. 2013; 75: 1545-1547
        • Elens L.
        • van Schaik R.H.
        • Panin N.
        • et al.
        Effect of a new functional CYP3A4 polymorphism on calcineurin inhibitors' dose requirements and trough blood levels in stable renal transplant patients.
        Pharmacogenomics. 2011; 12: 1383-1396
      1. 2020 Annual data report. Cystic Fibrosis Foundation, Bethesda, Maryland2020
        • Cogen J.
        • Emerson J.
        • Sanders D.B.
        • et al.
        Risk factors for lung function decline in a large cohort of young cystic fibrosis patients.
        Pediatr Pulmonol. 2015; 50: 763-770
        • Harun S.N.
        • Wainwright C.
        • Klein K.
        • et al.
        A systematic review of studies examining the rate of lung function decline in patients with cystic fibrosis.
        Paediatr Respir Rev. 2016; 20: 55-66
        • Hubert D.
        • Reglier-Poupet H.
        • Sermet-Gaudelus I.
        • et al.
        Association between Staphylococcus aureus alone or combined with Pseudomonas aeruginosa and the clinical condition of patients with cystic fibrosis.
        J Cyst Fibros. 2013; 12: 497-503
        • Kerem E.
        • Viviani L.
        • Zolin A.
        • et al.
        Factors associated with FEV1 decline in cystic fibrosis: analysis of the ECFS patient registry.
        Eur Respir J. 2014; 43: 125-133
        • Zemanick E.T.
        • Emerson J.
        • Thompson V.
        • et al.
        Clinical outcomes after initial pseudomonas acquisition in cystic fibrosis.
        Pediatr Pulmonol. 2015; 50: 42-48
        • Nichols D.P.
        • Paynter A.C.
        • Heltshe S.L.
        • et al.
        Clinical effectiveness of elexacaftor/tezacftor/ivacaftor in people with cystic fibrosis.
        Am J Respir Crit Care Med. 2021; 205: 529-539
        • Rowe S.M.
        • Heltshe S.L.
        • Gonska T.
        • et al.
        Clinical mechanism of the cystic fibrosis transmembrane conductance regulator potentiator ivacaftor in G551D-mediated cystic fibrosis.
        Am J Respir Crit Care Med. 2014; 190: 175-184
        • Davies J.C.
        • Wainwright C.E.
        • Canny G.J.
        • et al.
        Efficacy and safety of ivacaftor in patients aged 6 to 11 years with cystic fibrosis with a G551D mutation.
        Am J Respir Crit Care Med. 2013; 187: 1219-1225
        • Horsley A.R.
        • Gustafsson P.M.
        • Macleod K.A.
        • et al.
        Lung clearance index is a sensitive, repeatable and practical measure of airways disease in adults with cystic fibrosis.
        Thorax. 2008; 63: 135-140
        • Aurora P.
        • Bush A.
        • Gustafsson P.
        • et al.
        Multiple-breath washout as a marker of lung disease in preschool children with cystic fibrosis.
        Am J Respir Crit Care Med. 2005; 171: 249-256
        • Amin R.
        • Subbarao P.
        • Jabar A.
        • et al.
        Hypertonic saline improves the LCI in paediatric patients with CF with normal lung function.
        Thorax. 2010; 65: 379-383
        • Thomen R.P.
        • Walkup L.L.
        • Roach D.J.
        • et al.
        Hyperpolarized (129)Xe for investigation of mild cystic fibrosis lung disease in pediatric patients.
        J Cyst Fibros. 2017; 16: 275-282
        • Rayment J.H.
        • Couch M.J.
        • McDonald N.
        • et al.
        Hyperpolarised (129)Xe magnetic resonance imaging to monitor treatment response in children with cystic fibrosis.
        Eur Respir J. 2019; 53: 1802188
        • Goralski J.L.
        • Chung S.H.
        • Glass T.M.
        • et al.
        Dynamic perfluorinated gas MRI reveals abnormal ventilation despite normal FEV1 in cystic fibrosis.
        JCI insight. 2020; 5
        • Donaldson S.H.
        • Laube B.L.
        • Mogayzel P.
        • et al.
        Effect of lumacaftor-ivacaftor on mucociliary clearance and clinical outcomes in cystic fibrosis: results from the PROSPECT MCC sub-study.
        J Cyst Fibros. 2021; 21: 143-145
        • Leung H.M.
        • Birket S.E.
        • Hyun C.
        • et al.
        Intranasal micro-optical coherence tomography imaging for cystic fibrosis studies.
        Sci translational Med. 2019; 11: eaav3505
        • Shei R.J.
        • Peabody J.E.
        • Rowe S.M.
        Functional anatomic imaging of the airway surface.
        Ann Am Thorac Soc. 2018; 15: S177-S183
        • Donaldson S.H.
        • Laube B.L.
        • Corcoran T.E.
        • et al.
        Effect of ivacaftor on mucociliary clearance and clinical outcomes in cystic fibrosis patients with G551D-CFTR.
        JCI Insight. 2018; 3
        • Fidler M.C.
        • Beusmans J.
        • Panorchan P.
        • et al.
        Correlation of sweat chloride and percent predicted FEV(1) in cystic fibrosis patients treated with ivacaftor.
        J Cyst Fibros. 2017; 16: 41-44
        • Zemanick E.T.
        • Konstan M.W.
        • VanDevanter D.R.
        • et al.
        Measuring the impact of CFTR modulation on sweat chloride in cystic fibrosis: rationale and design of the CHEC-SC study.
        J Cyst Fibros. 2021; 20: 965-971
        • Ishak A.
        • Stick S.M.
        • Turkovic L.
        • et al.
        BAL inflammatory markers can predict pulmonary exacerbations in children with cystic fibrosis.
        Chest. 2020; 158: 2314-2322
        • Sagel S.D.
        • Kapsner R.K.
        • Osberg I.
        Induced sputum matrix metalloproteinase-9 correlates with lung function and airway inflammation in children with cystic fibrosis.
        Pediatr Pulmonol. 2005; 39: 224-232
        • Horati H.
        • Janssens H.M.
        • Margaroli C.
        • et al.
        Airway profile of bioactive lipids predicts early progression of lung disease in cystic fibrosis.
        J Cyst Fibros. 2020; 19: 902-909
        • Khanal S.
        • Webster M.
        • Niu N.
        • et al.
        SPLUNC1: a novel marker of cystic fibrosis exacerbations.
        Eur Respir J. 2021; 58
        • Wolfe C.
        • Pestian T.
        • Gecili E.
        • et al.
        Cystic fibrosis point of personalized detection (CFPOPD): an interactive web application.
        JMIR Med Inform. 2020; 8: e23530
        • Cogen J.D.
        • Faino A.V.
        • Onchiri F.
        • et al.
        Association between number of intravenous antipseudomonal antibiotics and clinical outcomes of pediatric cystic fibrosis pulmonary exacerbations.
        Clin Infect Dis. 2021; 73: 1589-1596
        • Lechtzin N.
        • John M.
        • Irizarry R.
        • et al.
        Outcomes of adults with cystic fibrosis infected with antibiotic-resistant Pseudomonas aeruginosa.
        Respiration. 2006; 73: 27-33
        • Kos R.
        • Brinkman P.
        • Neerincx A.H.
        • et al.
        Targeted exhaled breath analysis for detection of Pseudomonas aeruginosa in cystic fibrosis patients.
        J Cyst Fibros. 2021; 21: e28-e34
        • Gilchrist F.J.
        • Belcher J.
        • Jones A.M.
        • et al.
        Exhaled breath hydrogen cyanide as a marker of early Pseudomonas aeruginosa infection in children with cystic fibrosis.
        ERJ Open Res. 2015; 1: 00044-02015
        • Kapnadak S.G.
        • Dimango E.
        • Hadjiliadis D.
        • et al.
        Cystic Fibrosis Foundation consensus guidelines for the care of individuals with advanced cystic fibrosis lung disease.
        J Cyst Fibros. 2020; 19: 344-354
        • Ramos K.J.
        • Smith P.J.
        • McKone E.F.
        • et al.
        Lung transplant referral for individuals with cystic fibrosis: cystic Fibrosis Foundation consensus guidelines.
        J Cyst Fibros. 2019; 18: 321-333
        • Ren C.L.
        • Morgan R.L.
        • Oermann C.
        • et al.
        Cystic fibrosis foundation pulmonary guidelines. use of cystic fibrosis transmembrane conductance regulator modulator therapy in patients with cystic fibrosis.
        Ann Am Thorac Soc. 2018; 15: 271-280
        • Bell S.C.
        • Mall M.A.
        • Gutierrez H.
        • et al.
        The future of cystic fibrosis care: a global perspective.
        Lancet Respir Med. 2020; 8: 65-124
        • Nichols D.P.
        • Singh P.K.
        • Baines A.
        • et al.
        Testing the effects of combining azithromycin with inhaled tobramycin for P. aeruginosa in cystic fibrosis: a randomised, controlled clinical trial.
        Thorax, 2021
        • Goss C.H.
        • Heltshe S.L.
        • West N.E.
        • et al.
        A randomized trial of antimicrobial duration for cystic fibrosis pulmonary exacerbation treatment.
        Am J Respir Crit Care Med. 2021; 204: 1295-1305
        • Konstan M.W.
        • Byard P.J.
        • Hoppel C.L.
        • et al.
        Effect of high-dose ibuprofen in patients with cystic fibrosis.
        N Engl J Med. 1995; 332: 848-854
        • Elkins M.R.
        • Robinson M.
        • Rose B.R.
        • et al.
        A controlled trial of long-term inhaled hypertonic saline in patients with cystic fibrosis.
        N Engl J Med. 2006; 354: 229-240
        • Mayer-Hamblett N.
        • Nichols D.P.
        • Odem-Davis K.
        • et al.
        Evaluating the impact of stopping chronic therapies after modulator drug therapy in cystic fibrosis: the simplify clinical trial study design.
        Ann Am Thorac Soc. 2021; 18: 1397-1405
        • Ratjen F.
        • Davis S.D.
        • Stanojevic S.
        • et al.
        Inhaled hypertonic saline in preschool children with cystic fibrosis (SHIP): a multicentre, randomised, double-blind, placebo-controlled trial.
        Lancet Respir Med. 2019; 7: 802-809
        • Saiman L.
        • Marshall B.C.
        • Mayer-Hamblett N.
        • et al.
        Azithromycin in patients with cystic fibrosis chronically infected with Pseudomonas aeruginosa: a randomized controlled trial.
        JAMA. 2003; 290: 1749-1756
        • Volkova N.
        • Moy K.
        • Evans J.
        • et al.
        Disease progression in patients with cystic fibrosis treated with ivacaftor: data from national US and UK registries.
        J Cyst Fibros. 2020; 19: 68-79
        • Sawicki G.S.
        • Signorovitch J.E.
        • Zhang J.
        • et al.
        Reduced mortality in cystic fibrosis patients treated with tobramycin inhalation solution.
        Pediatr Pulmonol. 2012; 47: 44-52
        • Denis A.
        • Touzet S.
        • Diabate L.
        • et al.
        Quantifying long-term changes in lung function and exacerbations after initiation of azithromycin in cystic fibrosis.
        Ann Am Thorac Soc. 2020; 17: 195-201
        • Nichols D.P.
        • Odem-Davis K.
        • Cogen J.D.
        • et al.
        Pulmonary outcomes associated with long-term azithromycin therapy in cystic fibrosis.
        Am J Respir Crit Care Med. 2020; 201: 430-437
        • VanDyke R.D.
        • McPhail G.L.
        • Huang B.
        • et al.
        Inhaled tobramycin effectively reduces FEV1 decline in cystic fibrosis. An instrumental variables analysis.
        Ann Am Thorac Soc. 2013; 10: 205-212
        • Schluchter M.D.
        • Konstan M.W.
        • Xue L.
        • et al.
        Relationship between high-dose ibuprofen use and rate of decline in FEV1 among young patients with mild lung disease in the CFF Registry.
        Pediatr Pulmonol. 2004; 27 (322): A385
        • Burgel P.R.
        • Durieu I.
        • Chiron R.
        • et al.
        Rapid improvement after starting elexacaftor-tezacaftor-ivacaftor in patients with cystic fibrosis and advanced pulmonary disease.
        Am J Respir Crit Care Med. 2021; 204: 64-73
        • O'Shea K.M.
        • O'Carroll O.M.
        • Carroll C.
        • et al.
        Efficacy of elexacaftor/tezacaftor/ivacaftor in patients with cystic fibrosis and advanced lung disease.
        Eur Respir J. 2021; 57
        • Donaldson S.H.
        • Bennett W.D.
        • Zeman K.L.
        • et al.
        Mucus clearance and lung function in cystic fibrosis with hypertonic saline.
        N Engl J Med. 2006; 354: 241-250
        • Hisert K.B.
        • Heltshe S.L.
        • Pope C.
        • et al.
        Restoring cystic fibrosis transmembrane conductance regulator function reduces airway bacteria and inflammation in people with cystic fibrosis and chronic lung infections.
        Am J Respir Crit Care Med. 2017; 195: 1617-1628
        • Heltshe S.L.
        • Mayer-Hamblett N.
        • Burns J.L.
        • et al.
        Pseudomonas aeruginosa in cystic fibrosis patients with G551D-CFTR treated with ivacaftor.
        Clin Infect Dis : official Publ Infect Dis Soc America. 2015; 60: 703-712
        • Mayer-Hamblett N.
        • Retsch-Bogart G.
        • Kloster M.
        • et al.
        Azithromycin for early pseudomonas infection in cystic fibrosis. The OPTIMIZE Randomized Trial.
        Am J Respir Crit Care Med. 2018; 198: 1177-1187
        • Saiman L.
        • Anstead M.
        • Mayer-Hamblett N.
        • et al.
        Effect of azithromycin on pulmonary function in patients with cystic fibrosis uninfected with Pseudomonas aeruginosa: a randomized controlled trial.
        JAMA. 2010; 303: 1707-1715
        • Rosenfeld M.
        • Cunningham S.
        • Harris W.T.
        • et al.
        An open-label extension study of ivacaftor in children with CF and a CFTR gating mutation initiating treatment at age 2-5years (KLIMB).
        J Cyst Fibros. 2019; 18: 838-843
        • Rosenfeld M.
        • Wainwright C.E.
        • Higgins M.
        • et al.
        Ivacaftor treatment of cystic fibrosis in children aged 12 to <24 months and with a CFTR gating mutation (ARRIVAL): a phase 3 single-arm study.
        Lancet Respir Med. 2018; 6: 545-553
        • Breuer O.
        • Shoseyov D.
        • Koretz S.
        • et al.
        Ethical dilemma: elexacaftor-tezacaftor-ivacaftor or lung transplantation in cystic fibrosis and end-stage lung disease?.
        Chest. 2021; 161: 773-780