scholarly journals Clinical development of triple-combination CFTR modulators for cystic fibrosis patients with one or two F508del alleles

2019 ◽  
Vol 5 (2) ◽  
pp. 00082-2019 ◽  
Author(s):  
Jennifer L. Taylor-Cousar ◽  
Marcus A. Mall ◽  
Bonnie W. Ramsey ◽  
Edward F. McKone ◽  
Elizabeth Tullis ◽  
...  
Keyword(s):  
Cystic Fibrosis ◽  
Anion Channel ◽  
Triple Combination ◽  
Open Label ◽  
Cftr Protein ◽  
Trafficking Defects ◽  
Cf Transmembrane Conductance Regulator ◽  
And Function ◽  
Cftr Modulators

Cystic fibrosis (CF) is caused by mutations in the CF transmembrane conductance regulator gene (CFTR) that result in diminished quantity and/or function of the CFTR anion channel. F508del-CFTR, the most common CF-causing mutation (found in ∼90% of patients), causes severe processing and trafficking defects, resulting in decreased CFTR quantity and function. CFTR modulators are medications that increase the amount of mature CFTR protein (correctors) or enhance channel function (potentiators) at the cell surface.Combinations of CFTR correctors and potentiators (i.e. lumacaftor/ivacaftor, tezacaftor/ivacaftor) have demonstrated clinical benefit in subsets of patients. However, none are approved for patients with CF heterozygous for F508del-CFTR and a minimal function mutation, i.e. a mutation that produces either no protein or protein that is unresponsive to currently approved CFTR modulators. Next-generation CFTR correctors VX-659 and VX-445, each in triple combination with tezacaftor and ivacaftor, improve CFTR processing, trafficking and function in vitro and have demonstrated clinical improvements in phase 2 studies in patients with CF with one or two F508del-CFTR alleles.Here, we present the rationale and design of four randomised phase 3 studies, and their open-label extensions, evaluating VX-659 (ECLIPSE) or VX-445 (AURORA) plus tezacaftor and ivacaftor in patients with one or two F508del-CFTR alleles.

scholarly journals The combination of tezacaftor and ivacaftor in the treatment of patients with cystic fibrosis: clinical evidence and future prospects in cystic fibrosis therapy

2019 ◽  
Vol 13 ◽  
pp. 175346661984442 ◽  
Author(s):  
Sherstin T. Lommatzsch ◽  
Jennifer L. Taylor-Cousar
Keyword(s):  
Cystic Fibrosis ◽  
Clinical Evidence ◽  
Anion Channel ◽  
The United States ◽  
New Era ◽  
Sweat Chloride ◽  
Cftr Protein ◽  
Surface Liquid ◽  
Cftr Modulators ◽  
Epithelial Sodium Channel Enac

Years of tremendous study have dawned a new era for the treatment of cystic fibrosis (CF). For years CF care was rooted in the management of organ dysfunction resulting from the mal-effects of absent anion transport through the CF transmembrane regulator (CFTR) protein. CFTR, an adenosine triphosphate binding anion channel, has multiple functions, but primarily regulates the movement of chloride anions, thiocyanate and bicarbonate across luminal cell membranes. Additional roles include effects on other electrolyte channels such as the epithelial sodium channel (ENaC) and on pulmonary innate immunity. Inappropriate luminal anion movement leads to elevated sweat chloride concentrations, dehydrated airway surface liquid, overall viscous mucous production, and inspissated bile and pancreatic secretions. As a result, patients develop the well-known CF symptoms and disease-defining complications such as chronic cough, oily stools, recurrent pulmonary infections, bronchiectasis, chronic sinusitis and malnutrition. Traditionally, CF has been symptomatically managed, but over the past 6 years those with CF have been offered a new mode of therapy; CFTR protein modulation. These medications affect the basic defect in CF: abnormal CFTR function. Ivacaftor, approved for use in the United States in 2012, is the first medication in CF history to improve CFTR function at the molecular level. Its study and approval were followed by two additional CFTR modulators, lumacaftor/ivacaftor and tezacaftor/ivacaftor. To effectively use currently available CF therapies, clinicians should be familiar with the side effects of the drugs and their impacts on patient outcomes. As many new modulators are on the horizon, this information will equip providers to discuss the benefits and shortcomings of modulator therapy especially in the context of limited healthcare resources.

scholarly journals A multimodal iPSC platform for cystic fibrosis drug testing

2021 ◽  
Author(s):  
Andrew Berical ◽  
Rhianna Lee ◽  
Junjie Lu ◽  
Mary Lou Beermann ◽  
Jake LeSuer ◽  
...  
Keyword(s):  
Cystic Fibrosis ◽  
Drug Testing ◽  
Rare Variants ◽  
Anion Channel ◽  
Airway Epithelial Cells ◽  
In Vitro Assays ◽  
Patient Specific ◽  
Airway Epithelial ◽  
Cftr Modulators

Cystic fibrosis (CF) is a monogenic lung disease caused by dysfunction of the cystic fibrosis transmembrane regulator (CFTR) anion channel, resulting in significant morbidity and mortality. The progress in elucidating the role of the CFTR channel using established animal and cell-based models led to the recent discovery of effective CFTR modulators for most individuals with CF. However, a subset of individuals with CF do not respond to these modulators and there is an urgent need to develop novel therapeutic strategies. In this study, we assembled a panel of iPSCs derived from individuals with common or rare variants representative of three distinct classes of CFTR dysfunction. To measure CFTR function in patient-specific iPSCs we adapted two established in vitro assays of CFTR function to iPSC-derived airway cells. In both a 3-D spheroid assay using forskolin-induced swelling as well as planar cultures composed of polarized mucociliary airway epithelial cells, we quantified CFTR baseline function and response to CFTR modulators and detected genotype-specific differences. Our results demonstrate the potential of the human iPSC platform as a research tool to study cystic fibrosis and in particular accelerate therapeutic development for CF caused by rare mutations.

scholarly journals Cystic Fibrosis and Genotype-Dependent Therapy: Is There a Need for a Sex-Specific Therapy?

2020 ◽  
Vol 4 ◽  
pp. 247028972093702
Author(s):  
Neil A. Bradbury
Keyword(s):  
Cystic Fibrosis ◽  
Life Expectancy ◽  
Fluid Transport ◽  
Anion Channel ◽  
Steady Increase ◽  
Transmembrane Conductance ◽  
Multiple Organs ◽  
Cftr Protein ◽  
Cystic Fibrosis Transmembrane ◽  
Cftr Modulators

Cystic fibrosis (CF) is an autosomal recessive genetic disease caused by mutations in the cystic fibrosis transmembrane conductance regulation (CFTR) anion channel. Loss of CFTR protein and/or function disrupts chloride, bicarbonate, and fluid transport and also impacts epithelial sodium transport. Such altered ion and fluid transport produces mucus obstruction, inflammation, pulmonary infection, and damage to multiple organs. Although an autosomal disease, it is apparent that gender differences in life expectancy and quality of life do exist. Conventionally established therapies have treated the downstream sequelae of CFTR dysfunction and have led to a steady increase in life expectancy. Physicians now have access to medications that treat the basic defect in CF, in the form of CFTR modulators. These drugs target the trafficking and/or function of CFTR to improve clinical outcomes for patients. This review summarizes the science behind CFTR modulators and shows how these drugs have dramatically changed how patients with CF are treated. Surprisingly, although the drug target(s) are identical in males and females, CF females seem to display a greater improvement than their male counterparts.

scholarly journals Impact of Airway Inflammation on the Efficacy of CFTR Modulators

Cells ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 3260
Author(s):  
Carla M. P. Ribeiro ◽  
Martina Gentzsch
Keyword(s):  
Cystic Fibrosis ◽  
Airway Inflammation ◽  
Primary Cultures ◽  
Lavage Fluid ◽  
Improved Outcomes ◽  
Inflammatory Stimuli ◽  
Infection And Inflammation ◽  
The Impact ◽  
Cftr Modulators

Defective CFTR biogenesis and activity in cystic fibrosis airways leads to airway dehydration and impaired mucociliary clearance, resulting in chronic airway infection and inflammation. Most cystic fibrosis patients have at least one copy of the F508del CFTR mutation, which results in a protein retained in the endoplasmic reticulum and degraded by the proteosomal pathway. CFTR modulators, e.g., correctors, promote the transfer of F508del to the apical membrane, while potentiators increase CFTR activity. Corrector and potentiator double therapies modestly improve lung function, whereas triple therapies with two correctors and one potentiator indicate improved outcomes. Enhanced F508del rescue by CFTR modulators is achieved by exposing F508del/F508del primary cultures of human bronchial epithelia to relevant inflammatory stimuli, i.e., supernatant from mucopurulent material or bronchoalveolar lavage fluid from human cystic fibrosis airways. Inflammation enhances the biochemical and functional rescue of F508del by double or triple CFTR modulator therapy and overcomes abrogation of CFTR correction by chronic VX-770 treatment in vitro. Furthermore, the impact of inflammation on clinical outcomes linked to CFTR rescue has been recently suggested. This review discusses these data and possible mechanisms for airway inflammation-enhanced F508del rescue. Expanding the understanding of how airway inflammation improves CFTR rescue may benefit CF patients.

scholarly journals Progress in precision medicine in cystic fibrosis: a focus on CFTR modulator therapy

Breathe ◽  
2021 ◽  
Vol 17 (4) ◽  
pp. 210112
Author(s):  
Daniel H. Tewkesbury ◽  
Rebecca C. Robey ◽  
Peter J. Barry
Keyword(s):  
Cystic Fibrosis ◽  
Precision Medicine ◽  
Real World ◽  
Chloride Ion ◽  
Transmembrane Conductance Regulator ◽  
Therapeutic Approaches ◽  
Transmembrane Conductance ◽  
Cftr Protein ◽  
Cystic Fibrosis Transmembrane ◽  
Cftr Modulators

The genetic multisystem condition cystic fibrosis (CF) has seen a paradigm shift in therapeutic approaches within the past decade. Since the first clinical descriptions in the 1930s, treatment advances had focused on the downstream consequences of a dysfunctional cystic fibrosis transmembrane conductance regulator (CFTR) chloride ion channel. The discovery of the gene that codes for CFTR and an understanding of the way in which different genetic mutations lead to disruption of normal CFTR function have led to the creation and subsequent licensing of drugs that target this process. This marks an important move towards precision medicine in CF and results from clinical trials and real-world clinical practice have been impressive. In this review we outline how CFTR modulator drugs restore function to the CFTR protein and the progress that is being made in this field. We also describe the real-world impact of CFTR modulators on both pulmonary and multisystem complications of CF and what this will mean for the future of CF care.

scholarly journals A new Era of Personalized Medicine for Cystic Fibrosis – at Last!

2015 ◽  
Vol 22 (5) ◽  
pp. 257-260 ◽  
Author(s):  
Bradley S Quon ◽  
Pearce G Wilcox
Keyword(s):  
Cystic Fibrosis ◽  
Personalized Medicine ◽  
Late Phase ◽  
Structure And Function ◽  
Clinical Development ◽  
New Era ◽  
High Throughput Drug Screening ◽  
Cftr Protein ◽  
And Function ◽  
Screening Approaches

The gene responsible for cystic fibrosis (CF) was discovered 25 years ago. This breakthrough has enabled a sophisticated understanding of how various mutations lead to specific alterations in the structure and function of the CF transmembrane regulator (CFTR) protein. Until recently, all therapies in CF were focused on ameliorating the downstream consequences of CFTR dysfunction. High-throughput drug screening approaches have yielded compounds that can modify CFTR structure and function, thus targeting the basic defect in CF. The present article describes theCFTRmutational classes, reviews mutation-specific therapies currently in late-phase clinical development, and highlights research opportunities and challenges with personalized medicine in CF.

scholarly journals A European regulatory perspective on cystic fibrosis: current treatments, trends in drug development and translational challenges for CFTR modulators

2018 ◽  
Vol 27 (148) ◽  
pp. 170124 ◽  
Author(s):  
Stefano Ponzano ◽  
Giulia Nigrelli ◽  
Laura Fregonese ◽  
Irmgard Eichler ◽  
Fabio Bertozzi ◽  
...  
Keyword(s):  
Cystic Fibrosis ◽  
Drug Development ◽  
Forced Expiratory Volume ◽  
The European Union ◽  
End Points ◽  
Sweat Chloride ◽  
European Regulatory ◽  
Clinical Models ◽  
Cf Transmembrane Conductance Regulator ◽  
Cftr Modulators

In this article we analyse the current authorised treatments and trends in early drug development for cystic fibrosis (CF) in the European Union for the time period 2000–2016. The analysis indicates a significant improvement in the innovation and development of new potential medicines for CF, shifting from products that act on the symptoms of the disease towards new therapies targeting the cause of CF. However, within these new innovative medicines, results for CF transmembrane conductance regulator (CFTR) modulators indicate that one major challenge for turning a CF concept product into an actual medicine for the benefit of patients resides in the fact that, although pre-clinical models have shown good predictability for certain mutations, a good correlation to clinical end-points or biomarkers (e.g. forced expiratory volume in 1 s and sweat chloride) for all mutations has not yet been achieved. In this respect, the use of alternative end-points and innovative nonclinical models could be helpful for the understanding of those translational discrepancies. Collaborative endeavours to promote further research and development in these areas as well as early dialogue with the regulatory bodies available at the European competent authorities are recommended.

Murine colonic mucosa hyperproliferation. I. Elevated CFTR expression and enhanced cAMP-dependent Cl−secretion

2000 ◽  
Vol 278 (5) ◽  
pp. G753-G764 ◽  
Author(s):  
Shahid Umar ◽  
Jason Scott ◽  
Joseph H. Sellin ◽  
William P. Dubinsky ◽  
Andrew P. Morris
Keyword(s):  
Cystic Fibrosis ◽  
Fluid Transport ◽  
Cellular Proliferation ◽  
Neck Region ◽  
Anion Channel ◽  
Cellular Level ◽  
Cystic Fibrosis Gene ◽  
Mrna And Protein Expression

Fluid transport in the large intestine is mediated by the cystic fibrosis gene product and cAMP-dependent anion channel cystic fibrosis transmembrane conductance regulator (CFTR). cAMP-mediated Cl−secretion by gastrointestinal cell lines in vitro has been positively correlated with the insertion of CFTR into the apical membrane of differentiated senescent colonocytes and negatively correlated with the failure of CFTR to insert into the plasma membrane of their undifferentiated proliferating counterparts. In native tissues, this relationship remains unresolved. We demonstrate, in a transmissible murine colonic hyperplasia (TMCH) model, that (8-fold) colonocyte proliferation was accompanied by increased cellular CFTR mRNA and protein expression (8.3- and 2.4-fold, respectively) and enhanced mucosal cAMP-dependent Cl−secretion (2.3-fold). By immunofluorescence microscopy, cellular CFTR expression was restricted to the apical pole of cells at the base of the epithelial crypt. In contrast, increased cellular proliferation in vivo led to increases in both the cellular level and the total number of cells expressing this anion channel, with cellular CFTR staining extending into the crypt neck region. Hyperproliferating colonocytes accumulated large amounts of CFTR in apically oriented subcellular perinuclear compartments. This novel mode of CFTR regulation may explain why high endogenous levels of cellular CFTR mRNA and protein within the TMCH epithelium were not matched with larger increases in transmucosal CFTR Cl−current.

Antisense oligonucleotides to CFTR confer a cystic fibrosis phenotype on B lymphocytes

1992 ◽  
Vol 263 (6) ◽  
pp. C1147-C1151 ◽  
Author(s):  
R. D. Krauss ◽  
G. Berta ◽  
T. A. Rado ◽  
J. K. Bubien
Keyword(s):  
Cell Cycle ◽  
Cystic Fibrosis ◽  
Antisense Oligonucleotides ◽  
T84 Cells ◽  
Cftr Protein ◽  
Low Levels ◽  
B Lymphoid ◽  
Cycle Dependent ◽  
Cl Permeability

Cystic fibrosis transmembrane conductance regulator (CFTR) is expressed at low levels in nonepithelial cells. Recently, we demonstrated that CFTR is responsible for cell cycle-dependent adenosine 3',5'-cyclic monophosphate-responsive Cl- permeability in lymphocytes. Agonist responsiveness of cystic fibrosis (CF) lymphocytes was restored by transfection with plasmid containing wild type CFTR cDNA. CFTR mRNA is expressed in the B lymphoid cell line GM03299; however, quantitative reverse transcriptase-polymerase chain reaction indicates that the level of CFTR mRNA is at least 1,000 times lower than in T84 cells. CFTR protein could not be detected by Western blot or by immunoprecipitation of in vitro phosphorylated protein. However, antisense oligonucleotides representing codons 1-12 of CFTR caused a complete inhibition of cell cycle-dependent Cl-permeability [as determined by 6-methoxy-N-(3-sulfopropyl)-quinolinium fluorescence digital-imaging microscopy], thereby inducing normal cells to acquire a "CF phenotype." These studies provide direct evidence that a CFTR-associated Cl- permeability is present and measurable in lymphocytes, even though CFTR mRNA and protein are expressed at low levels.

Sign in / Sign up

Export Citation Format

Share Document