1
|
Sawicki GS, Wicha WW, Hiley TS, Close NC, Gelone SP, Guico-Pabia CJ. Safety and Pharmacokinetics Following Oral or Intravenous Lefamulin in Adults With Cystic Fibrosis. Clin Ther 2024; 46:96-103. [PMID: 38195348 DOI: 10.1016/j.clinthera.2023.12.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Revised: 10/27/2023] [Accepted: 12/03/2023] [Indexed: 01/11/2024]
Abstract
PURPOSE Methicillin-resistant Staphylococcus aureus infections are increasing in prevalence in patients with cystic fibrosis (CF) and are associated with worsening lung function and increased mortality. Lefamulin is a pleuromutilin antimicrobial approved to treat community-acquired bacterial pneumonia based on potent in vitro activity and clinical efficacy. This Phase I, open-label, randomized crossover study assessed the safety and pharmacokinetic profile of oral and intravenous (IV) lefamulin in adults with CF. METHODS The study comprised 2 dosing periods in which adults with CF (N = 13) received a single dose of lefamulin via a 150-mg IV infusion or 600-mg immediate-release orally administered tablet, separated by a 4- to 7-day washout period. Pharmacokinetic and safety parameters were assessed after lefamulin treatment. FINDINGS Single doses of lefamulin administered via oral tablet or IV infusion resulted in comparable drug exposure, and sputum analysis suggested rapid penetration of lefamulin into the lung. Comparison of the present results with those obtained from prior single-dose studies of healthy volunteers indicate no meaningful difference in the pharmacokinetic properties of lefamulin in patients with CF. Treatment-emergent adverse events were consistent with previous reports, and the majority were mild in severity. IMPLICATIONS These results show similar lefamulin pharmacokinetic and safety profiles between patients with CF and healthy volunteers receiving the same oral and IV doses, suggesting no need for lefamulin dose adjustment in patients with CF and indicating the potential of lefamulin as therapy for lung infections in patients with CF. CLINICALTRIALS gov identifier: NCT05225805.
Collapse
Affiliation(s)
| | | | - Tara S Hiley
- Nabriva Therapeutics US, Inc, Fort Washington, Pennsylvania, USA
| | | | - Steven P Gelone
- Nabriva Therapeutics US, Inc, Fort Washington, Pennsylvania, USA
| | | |
Collapse
|
2
|
Nakhla DS, Mekkawy AI, Naguib YW, Silva AD, Gao D, Ah Kim J, Alhaj-Suliman SO, Acri TM, Kumar Patel K, Ernst S, Stoltz DA, Welsh MJ, Salem AK. Injectable long-acting ivacaftor-loaded poly (lactide-co-glycolide) microparticle formulations for the treatment of cystic fibrosis: In vitro characterization and in vivo pharmacokinetics in mice. Int J Pharm 2024; 650:123693. [PMID: 38081555 PMCID: PMC10843602 DOI: 10.1016/j.ijpharm.2023.123693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Revised: 12/03/2023] [Accepted: 12/08/2023] [Indexed: 12/25/2023]
Abstract
Optimizing a sustained-release drug delivery system for the treatment of cystic fibrosis (CF) is crucial for decreasing the dosing frequency and improving patients' compliance with the treatment regimen. In the current work, we developed an injectable poly(D,L-lactide-co-glycolide) (PLGA) microparticle formulation loaded with ivacaftor, a cystic fibrosis transmembrane conductance regulator (CFTR) potentiator that increases the open probability of the CFTR anion channel, using a single emulsion solvent evaporation technique. We aimed to study the effect of different parameters on the characteristics of the prepared formulations to select an optimized microparticle formulation to be used in an in vivo pharmacokinetic study in mice. First, a suite of ivacaftor-loaded microparticles were prepared using different formulation parameters in order to study the effect of varying these parameters on microparticle size, morphology, drug loading, encapsulation efficiency, and in vitro release profiles. Prepared microparticles were spherical with diameters ranging from 1.91-6.93 µm, percent drug loading (% DL) of 3.91-10.3%, percent encapsulation efficiencies (% EE) of 26.6-100%, and an overall slow cumulative release profile. We selected the formulation that demonstrated optimal combined % DL and % EE values (8.25 and 90.7%, respectively) for further studies. These microparticles had an average particle size of 6.83 µm and a slow tri-phasic in vitro release profile (up to 6 weeks). In vivo pharmacokinetic studies in mice showed that the subcutaneously injected microparticles resulted in steady plasma levels of ivacaftor over a period of 28 days, and a 6-fold increase in AUC 0 - t (71.6 µg/mL*h) compared to the intravenously injected soluble ivacaftor (12.3 µg/mL*h). Our results suggest that this novel ivacaftor-loaded microparticle formulation could potentially eliminate the need for the frequent daily administration of ivacaftor to people with CF thus improving their compliance and ensuring successful treatment outcomes.
Collapse
Affiliation(s)
- David S Nakhla
- Department of Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, University of Iowa, Iowa City, IA 52242, USA
| | - Aml I Mekkawy
- Department of Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, University of Iowa, Iowa City, IA 52242, USA; Department of Pharmaceutics and Clinical Pharmacy, Faculty of Pharmacy, Sohag University, Sohag, Sohag 82524, Egypt
| | - Youssef W Naguib
- Department of Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, University of Iowa, Iowa City, IA 52242, USA
| | - Aaron D Silva
- Department of Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, University of Iowa, Iowa City, IA 52242, USA
| | - Dylan Gao
- Department of Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, University of Iowa, Iowa City, IA 52242, USA
| | - Jeong Ah Kim
- Department of Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, University of Iowa, Iowa City, IA 52242, USA
| | - Suhaila O Alhaj-Suliman
- Department of Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, University of Iowa, Iowa City, IA 52242, USA
| | - Timothy M Acri
- Department of Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, University of Iowa, Iowa City, IA 52242, USA
| | - Krishna Kumar Patel
- Department of Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, University of Iowa, Iowa City, IA 52242, USA
| | - Sarah Ernst
- Howard Hughes Medical Institute, Roy J. and Lucille A. Carver College of Medicine University of Iowa, Iowa City, IA 52242, USA; Department of Internal Medicine, Roy J. and Lucille A. Carver College of Medicine University of Iowa, Iowa City, IA 52242, USA
| | - David A Stoltz
- Department of Internal Medicine, Roy J. and Lucille A. Carver College of Medicine University of Iowa, Iowa City, IA 52242, USA; Departments of Molecular Physiology and Biophysics, Roy J. and Lucille A. Carver College of Medicine University of Iowa, Iowa City, IA 52242, USA
| | - Michael J Welsh
- Howard Hughes Medical Institute, Roy J. and Lucille A. Carver College of Medicine University of Iowa, Iowa City, IA 52242, USA; Department of Internal Medicine, Roy J. and Lucille A. Carver College of Medicine University of Iowa, Iowa City, IA 52242, USA; Departments of Molecular Physiology and Biophysics, Roy J. and Lucille A. Carver College of Medicine University of Iowa, Iowa City, IA 52242, USA
| | - Aliasger K Salem
- Department of Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, University of Iowa, Iowa City, IA 52242, USA; Holden Comprehensive Cancer Center, University of Iowa, Iowa City, IA 52242, USA.
| |
Collapse
|
3
|
Purkayastha D, Agtarap K, Wong K, Pereira O, Co J, Pakhale S, Kanji S. Drug-drug interactions with CFTR modulator therapy in cystic fibrosis: Focus on Trikafta®/Kaftrio®. J Cyst Fibros 2023; 22:478-483. [PMID: 36653239 DOI: 10.1016/j.jcf.2023.01.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 12/21/2022] [Accepted: 01/11/2023] [Indexed: 01/18/2023]
Abstract
The combination of CFTR modulators ivacaftor, tezacaftor and elexacaftor (Trikafta®, Kaftrio®) significantly improve outcomes, including survival in a broad range of cystic fibrosis patients. These drugs have complicated metabolic profiles that make the potential for drug interactions an important consideration for prescribers, care providers and patients. Prolonged survival also increases risk of age-related disease and their associated pharmacotherapy, further increasing the risk of drug interactions and the need for increased vigilance amongst care providers. We systematically searched the literature for studies identifying and evaluating pharmacokinetic and pharmacodynamic drug interactions involving the components of Trikafta®/Kaftrio®. We also searched electronic databases of drugs for possible drug interactions based on metabolic profiles. We identified 86 potential drug interactions of which 13 were supported by 14 studies. There is a significant need for research to describe the likelihood, magnitude and clinical impact of the drug interactions proposed here.
Collapse
Affiliation(s)
| | | | - Kristy Wong
- University of Waterloo, Kitchener, ON, Canada
| | | | - Jannie Co
- The Ottawa Hospital, Ottawa, ON, Canada
| | - Smita Pakhale
- Department of Medicine, The Ottawa Hospital, Ottawa Hospital Research Institute, University of Ottawa, Ottawa, ON, Canada
| | - Salmaan Kanji
- Department of Pharmacy, The Ottawa Hospital, Ottawa Hospital Research Institute, 501 Smyth Rd, Ottawa, ON K1H 8L6, Canada.
| |
Collapse
|
4
|
Hong E, Shi A, Beringer P. Drug-drug interactions involving CFTR modulators: a review of the evidence and clinical implications. Expert Opin Drug Metab Toxicol 2023; 19:203-216. [PMID: 37259485 DOI: 10.1080/17425255.2023.2220960] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Accepted: 05/30/2023] [Indexed: 06/02/2023]
Abstract
INTRODUCTION Cystic fibrosis (CF) is characterized by mucus accumulation impairing the lungs, gastrointestinal tract, and other organs. Cystic fibrosis transmembrane conductance regulator (CFTR) modulators (ivacaftor, tezacaftor, elexacaftor, and lumacaftor) significantly improve lung function and nutritional status; however, they are substrates, inhibitors, and/or inducers of certain CYP enzymes and transporters, raising the risk of drug-drug interactions (DDI) with common CF medications. AREAS COVERED A literature search was conducted for DDIs involving CFTR modulators by reviewing new drug applications, drug package inserts, clinical studies, and validated databases of substrates, inhibitors, and inducers. Clinically, CYP3A inducers and inhibitors significantly decrease and increase systemic concentrations of elexacaftor/tezacaftor/ivacaftor, respectively. Additionally, lumacaftor and ivacaftor alter concentrations of CYP3A and P-gp substrates. Potential DDIs without current clinical evidence include ivacaftor and elexacaftor's effect on CYP2C9 and OATP1B1/3 substrates, respectively, and OATP1B1/3 and P-gp inhibitors' effect on tezacaftor. A literature review was conducted using PubMed. EXPERT OPINION Dosing recommendations for CFTR modulators with DDIs are relatively comprehensive; however, recommendations on timing of dosing transition of CFTR modulators when CYP3A inhibitors are initiated or discontinued is incomplete. Certain drug interactions may be managed by choosing an alternative treatment to avoid/minimize DDIs. Next generation CFTR modulator therapies under development are expected to provide increased activity with reduced DDI risk.
Collapse
Affiliation(s)
- Eunjin Hong
- Department of Clinical Pharmacy, USC Alfred E. Mann School of Pharmacy and Pharmaceutical Sciences, University of Southern California, Los Angeles, CA, USA
| | - Alan Shi
- Department of Clinical Pharmacy, USC Alfred E. Mann School of Pharmacy and Pharmaceutical Sciences, University of Southern California, Los Angeles, CA, USA
| | - Paul Beringer
- Department of Clinical Pharmacy, USC Alfred E. Mann School of Pharmacy and Pharmaceutical Sciences, University of Southern California, Los Angeles, CA, USA
- USC Anton Yelchin CF Clinic, Los Angeles, CA, USA
| |
Collapse
|
5
|
Guimbellot JS, Ryan KJ, Anderson JD, Parker KL, Odom LV, Rowe SM, Acosta EP. Plasma and cellular ivacaftor concentrations in patients with cystic fibrosis. Pediatr Pulmonol 2022; 57:2745-2753. [PMID: 35927224 PMCID: PMC9588676 DOI: 10.1002/ppul.26093] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Revised: 06/29/2022] [Accepted: 07/25/2022] [Indexed: 11/08/2022]
Abstract
Access to cystic fibrosis transmembrane conductance regulator (CFTR) modulators has been gradually increasing for people with cystic fibrosis, the first of which was ivacaftor, a CFTR potentiator that is part of all clinically available modulator treatments. In this study, we hypothesized that the steady-state concentrations in blood and tissue are highly variable in patients taking ivacaftor in a real-world context, which may have an impact on the treatment approach. We collected nasal epithelial cells to estimate target site concentrations and blood samples to estimate pharmacokinetic parameters at a steady state. We found that patients on ivacaftor monotherapy have variable concentrations well above the maximal effective concentration and may maintain concentrations necessary for the clinical benefit even if dosing is reduced. We also are the first to provide detailed target site concentration data over time, which shows that tissue concentrations do not fluctuate significantly and do not correlate with plasma concentrations. These findings show that some patients may have higher-than-expected concentrations and may benefit from tailored dosing to balance clinical response with side effects or adherence needs.
Collapse
Affiliation(s)
- Jennifer S. Guimbellot
- Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham (UAB), Birmingham, AL
- Department of Pediatrics, Division of Pulmonary and Sleep Medicine, UAB, Birmingham, AL
| | - Kevin J. Ryan
- Department of Pharmacology and Toxicology, Division of Clinical Pharmacology, UAB, Birmingham, AL
| | - Justin D. Anderson
- Department of Pediatrics, Division of Pulmonary and Sleep Medicine, UAB, Birmingham, AL
| | - Kennedy L. Parker
- Department of Pediatrics, Division of Pulmonary and Sleep Medicine, UAB, Birmingham, AL
| | - L. Victoria Odom
- Department of Pediatrics, Division of Pulmonary and Sleep Medicine, UAB, Birmingham, AL
| | - Steven M. Rowe
- Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham (UAB), Birmingham, AL
- Department of Pediatrics, Division of Pulmonary and Sleep Medicine, UAB, Birmingham, AL
- Departments of Medicine and Cell Developmental and Integrative Biology, UAB, Birmingham, AL
| | - Edward P. Acosta
- Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham (UAB), Birmingham, AL
- Department of Pharmacology and Toxicology, Division of Clinical Pharmacology, UAB, Birmingham, AL
| |
Collapse
|
6
|
Therapeutic Drug Monitoring of Ivacaftor, Lumacaftor, Tezacaftor, and Elexacaftor in Cystic Fibrosis: Where Are We Now? Pharmaceutics 2022; 14:pharmaceutics14081674. [PMID: 36015300 PMCID: PMC9412421 DOI: 10.3390/pharmaceutics14081674] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 07/20/2022] [Accepted: 07/23/2022] [Indexed: 11/16/2022] Open
Abstract
Drugs modulating the cystic fibrosis transmembrane conductance regulator (CFTR) protein, namely ivacaftor, lumacaftor, tezacaftor, and elexacaftor, are currently revolutionizing the management of patients with cystic fibrosis (CF), particularly those with at least one F508del variant (up to 85% of patients). These “caftor” drugs are mainly metabolized by cytochromes P450 3A, whose enzymatic activity is influenced by environmental factors, and are sensitive to inhibition and induction. Hence, CFTR modulators are characterized by an important interindividual pharmacokinetic variability and are also prone to drug–drug interactions. However, these CFTR modulators are given at standardized dosages, while they meet all criteria for a formal therapeutic drug monitoring (TDM) program that should be considered in cases of clinical toxicity, less-than-expected clinical response, drug or food interactions, distinct patient subgroups (i.e., pediatrics), and for monitoring short-term adherence. While the information on CFTR drug exposure–clinical response relationships is still limited, we review the current evidence of the potential interest in the TDM of caftor drugs in real-life settings.
Collapse
|
7
|
Miao Y, Zhao S, Zuo J, Sun J, Wang J. Reduced the Food Effect and Enhanced the Oral Bioavailability of Ivacaftor by Self-Nanoemulsifying Drug Delivery System (SNEDDS) Using a New Oil Phase. Drug Des Devel Ther 2022; 16:1531-1546. [PMID: 35637746 PMCID: PMC9143795 DOI: 10.2147/dddt.s356967] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Accepted: 05/17/2022] [Indexed: 12/21/2022] Open
Abstract
Purpose The purpose of this work was to develop an ivacaftor self-nanoemulsion drug delivery system (IVA-SNEDDS) using the newly developed double headed miscellaneous lipid (DHML) as oil phase to reduce the food effect and inter-individual absorption variability of IVA. Methods The lipids with the greatest solubility to IVA were selected as the oil phase of IVA-SNEDDS by saturation solubility method. Then, among different surfactants and co-surfactants, those with good emulsifying ability for the selected oil phase were selected, and the proportion of surfactant and co-surfactant was further selected by pseudo-ternary phase diagram. The prepared IVA-SNEDDS were screened and evaluated in vitro and in beagle dogs. Results The optimized IVA-SNEDDS formulation consisting of DHML, Tween 80, and Transcutol HP with the weight ratio of 2:2:1 was physically stable and it was easy to disperse in water, pH 1.2 hydrochloric acid and pH 6.8 phosphate buffer solution, and generated a fine homogeneous nanoemulsion, with mean globule size less than 75 nm regardless of dilution ratio. In vitro drug release studies showed that the drug in IVA-SNEDDS could be completely released in a short time, while the drug release in IVA-suspension was less than 1% at 60 min. In vivo, using IVA-suspension (Fed) as a reference, the relative oral bioavailability of IVA-suspension (Fasted), IVA-SNEDDS (Fasted), and IVA-SNEDDS (Fed) were 23.35%, 153.63%, and 149.89%, respectively. This showed that IVA-SNEDDS could eliminate the positive food effect, improve the oral bioavailability, and reduce the IVA absorption difference between individuals. Conclusion As the oil phase of SNEDDS, DHML can significantly improve the drug solubility and drug loading of IVA-SNEDDS. Moreover, DHML was easily emulsified and can effectively form a nanoemulsion in vivo and in vitro. The prepared IVA-SNEDDS can reduce the inter-individual absorption variability of IVA, eliminate its food effect and improve its oral bioavailability.
Collapse
Affiliation(s)
- Yanfei Miao
- College of Chemistry and Chemical Engineering, Taishan University, Tai'an, People's Republic of China
| | - Shihua Zhao
- College of Chemistry and Chemical Engineering, Taishan University, Tai'an, People's Republic of China
| | - Jian Zuo
- College of Chemistry and Chemical Engineering, Taishan University, Tai'an, People's Republic of China
| | - Jiqin Sun
- College of Chemistry and Chemical Engineering, Taishan University, Tai'an, People's Republic of China
| | - Jingnan Wang
- School of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, People's Republic of China
| |
Collapse
|
8
|
Hong E, Almond LM, Chung PS, Rao AP, Beringer PM. Physiologically-Based Pharmacokinetic-Led Guidance for Patients With Cystic Fibrosis Taking Elexacaftor-Tezacaftor-Ivacaftor With Nirmatrelvir-Ritonavir for the Treatment of COVID-19. Clin Pharmacol Ther 2022; 111:1324-1333. [PMID: 35292968 PMCID: PMC9087007 DOI: 10.1002/cpt.2585] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2022] [Accepted: 03/04/2022] [Indexed: 12/11/2022]
Abstract
Cystic fibrosis transmembrane conductance regulator (CFTR) modulating therapies, including elexacaftor-tezacaftor-ivacaftor, are primarily eliminated through cytochrome P450 (CYP) 3A-mediated metabolism. This creates a therapeutic challenge to the treatment of coronavirus disease 2019 (COVID-19) with nirmatrelvir-ritonavir in people with cystic fibrosis (CF) due to the potential for significant drug-drug interactions (DDIs). However, the population with CF is more at risk of serious illness following COVID-19 infection and hence it is important to manage the DDI risk and provide treatment options. CYP3A-mediated DDI of elexacaftor-tezacaftor-ivacaftor was evaluated using a physiologically-based pharmacokinetic modeling approach. Modeling was performed incorporating physiological information and drug-dependent parameters of elexacaftor-tezacaftor-ivacaftor to predict the effect of ritonavir (the CYP3A inhibiting component of the combination) on the pharmacokinetics of elexacaftor-tezacaftor-ivacaftor. The elexacaftor-tezacaftor-ivacaftor models were verified using independent clinical pharmacokinetic and DDI data of elexacaftor-tezacaftor-ivacaftor with a range of CYP3A modulators. When ritonavir was administered on Days 1 through 5, the predicted area under the curve (AUC) ratio of ivacaftor (the most sensitive CYP3A substrate) on Day 6 was 9.31, indicating that its metabolism was strongly inhibited. Based on the predicted DDI, the dose of elexacaftor-tezacaftor-ivacaftor should be reduced when coadministered with nirmatrelvir-ritonavir to elexacaftor 200 mg-tezacaftor 100 mg-ivacaftor 150 mg on Days 1 and 5, with delayed resumption of full-dose elexacaftor-tezacaftor-ivacaftor on Day 9, considering the residual inhibitory effect of ritonavir as a mechanism-based inhibitor. The simulation predicts a regimen of elexacaftor-tezacaftor-ivacaftor administered concomitantly with nirmatrelvir-ritonavir in people with CF that will likely decrease the impact of the drug interaction.
Collapse
Affiliation(s)
- Eunjin Hong
- Department of Clinical Pharmacy, School of Pharmacy, University of Southern California, Los Angeles, California, USA
| | | | - Peter S Chung
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Keck School of Medicine, University of Southern California, Los Angeles, California, USA.,University of Southern California, Anton Yelchin Cystic Fibrosis Clinic, Los Angeles, California, USA
| | - Adupa P Rao
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Keck School of Medicine, University of Southern California, Los Angeles, California, USA.,University of Southern California, Anton Yelchin Cystic Fibrosis Clinic, Los Angeles, California, USA
| | - Paul M Beringer
- Department of Clinical Pharmacy, School of Pharmacy, University of Southern California, Los Angeles, California, USA.,University of Southern California, Anton Yelchin Cystic Fibrosis Clinic, Los Angeles, California, USA
| |
Collapse
|
9
|
Structure of ABCB1/P-Glycoprotein in the Presence of the CFTR Potentiator Ivacaftor. MEMBRANES 2021; 11:membranes11120923. [PMID: 34940424 PMCID: PMC8703531 DOI: 10.3390/membranes11120923] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 11/16/2021] [Accepted: 11/23/2021] [Indexed: 12/26/2022]
Abstract
ABCB1/P-glycoprotein is an ATP binding cassette transporter that is involved in the clearance of xenobiotics, and it affects the disposition of many drugs in the body. Conformational flexibility of the protein within the membrane is an intrinsic part of its mechanism of action, but this has made structural studies challenging. Here, we have studied different conformations of P-glycoprotein simultaneously in the presence of ivacaftor, a known competitive inhibitor. In order to conduct this, we used high contrast cryo-electron microscopy imaging with a Volta phase plate. We associate the presence of ivacaftor with the appearance of an additional density in one of the conformational states detected. The additional density is in the central aqueous cavity and is associated with a wider separation of the two halves of the transporter in the inward-facing state. Conformational changes to the nucleotide-binding domains are also observed and may help to explain the stimulation of ATPase activity that occurs when transported substrate is bound in many ATP binding cassette transporters.
Collapse
|
10
|
Barbieri A, Thonghin N, Shafi T, Prince SM, Collins RF, Ford RC. Structure of ABCB1/P-glycoprotein bound to the CFTR potentiator ivacaftor.. [DOI: 10.1101/2021.06.11.448073] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
Abstract
AbstractABCB1 (P-glycoprotein) is an ATP binding cassette transporter that is involved in the clearance of xenobiotics and it affects the disposition of many drugs in the body. Here we have studied ABCB1 in the drug-bound and drug-free states, simultaneously, using high contrast cryo-electron microscopy imaging and a Volta phase plate. The binding of the potent CFTR potentiator, ivacaftor, at a site in the central aqueous cavity is mediated by transmembrane α-helices 3,6,10,11 & 12. Binding is associated with a wider separation of the two halves of the transporter in the inward-facing state. Induced-fit changes the nucleotide binding domains in a way that may explain their increased affinity for ATP when drug is bound. Comparison of ivacaftor-bound structures of CFTR and ABCB1 suggests common features in the binding modes.
Collapse
|
11
|
van der Meer R, Wilms EB, Sturm R, Heijerman HGM. Pharmacokinetic interactions between ivacaftor and cytochrome P450 3A4 inhibitors in people with cystic fibrosis and healthy controls. J Cyst Fibros 2021; 20:e72-e76. [PMID: 34006500 DOI: 10.1016/j.jcf.2021.04.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 04/11/2021] [Accepted: 04/12/2021] [Indexed: 11/28/2022]
Abstract
BACKGROUND Ivacaftor is currently the only CFTR potentiator approved and is increasingly used since the development of CFTR correctors. Ivacaftor is metabolized by CYP3A4 and therefore dose reduction is required when treating patients on ivacaftor with CYP3A4 inhibiting drugs. As this advice is based on studies in healthy volunteers and not in cystic fibrosis (CF) patients, we need to investigate this in both groups to be able to extrapolate these data to CF. METHODS A cohort of CF patients and healthy subjects were exposed to a single dose of ivacaftor in combination with a strong (ritonavir), moderate (clarithromycin) and mild (azithromycin) CYP3A4 inhibitor. Ivacaftor concentrations were measured in all blood samples in order to calculate the pharmacokinetic parameters for ivacaftor. RESULTS We found that exposure to ivacaftor was higher in healthy volunteers than in subjects with CF. However this difference was not statistically significant. No differences were observed in the interaction potential of CYP3A4 inhibitors between both study groups. The strong CYP3A4 inhibitor ritonavir, increased exposure to ivacaftor 7 times. CONCLUSION Our data support current recommendations for dose adjustment of ivacaftor in case of co-treatment with CYP3A4 inhibitors in people with CF. However, exposure to ivacaftor was higher in healthy subjects than in CF patients. Further study is needed to investigate the cause and implication of this difference.
Collapse
Affiliation(s)
- Renske van der Meer
- Department of Pulmonology and Adult CF Centre, Haga Hospital, Els Borst-Eilersplein 275, 2545 AA The Hague, Netherlands.
| | - Erik B Wilms
- Central Hospital Pharmacy, Charlotte Jacobslaan 70, 2545 AB The Hague, Netherlands
| | - Richart Sturm
- Central Hospital Pharmacy, Charlotte Jacobslaan 70, 2545 AB The Hague, Netherlands
| | - Harry G M Heijerman
- Department of Pulmonology and Adult CF Centre, University Medical Centre Utrecht, Heidelberglaan 100, 3584 CX Utrecht, Netherlands
| |
Collapse
|
12
|
Guimbellot JS, Ryan KJ, Anderson JD, Liu Z, Kersh L, Esther CR, Rowe SM, Acosta EP. Variable cellular ivacaftor concentrations in people with cystic fibrosis on modulator therapy. J Cyst Fibros 2020; 19:742-745. [PMID: 32044246 PMCID: PMC7706073 DOI: 10.1016/j.jcf.2020.01.011] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Revised: 01/10/2020] [Accepted: 01/26/2020] [Indexed: 12/17/2022]
Abstract
The development of CFTR modulators has transformed the care of patients with cystic fibrosis (CF). Although the clinical efficacy of modulators depends on their concentrations in target tissues, the pharmacokinetic properties of these drugs in epithelia are not utilized to guide patient care. We developed assays to quantitate ivacaftor in cells and plasma from patients on modulator therapy, and our analyses revealed that cellular ivacaftor concentrations differ from plasma concentrations measured concurrently, with evidence of in vivo accumulation of ivacaftor in the cells of patients. While the nature of this study is exploratory and limited by a small number of patients, these findings suggest that techniques to measure modulator concentrations in vivo will be essential to interpreting their clinical impact, particularly given the evidence that ivacaftor concentrations influence the activity and stability of restored CFTR protein.
Collapse
Affiliation(s)
- Jennifer S Guimbellot
- Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham (UAB), Birmingham, AL, United States; Department of Pediatrics, Division of Pulmonary and Sleep Medicine, UAB, Birmingham, AL, United States.
| | - Kevin J Ryan
- Department of Pharmacology and Toxicology, Division of Clinical Pharmacology, UAB, Birmingham, AL, United States
| | - Justin D Anderson
- Department of Pediatrics, Division of Pulmonary and Sleep Medicine, UAB, Birmingham, AL, United States
| | - Zhongyu Liu
- Department of Pediatrics, Division of Pulmonary and Sleep Medicine, UAB, Birmingham, AL, United States
| | - Latona Kersh
- Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham (UAB), Birmingham, AL, United States
| | - Charles R Esther
- Marsico Lung Institute, University of North Carolina, Chapel Hill, NC, United States
| | - Steven M Rowe
- Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham (UAB), Birmingham, AL, United States; Department of Pediatrics, Division of Pulmonary and Sleep Medicine, UAB, Birmingham, AL, United States; Departments of Medicine and Cell Developmental and Integrative Biology, UAB, Birmingham, AL, United States
| | - Edward P Acosta
- Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham (UAB), Birmingham, AL, United States; Department of Pharmacology and Toxicology, Division of Clinical Pharmacology, UAB, Birmingham, AL, United States
| |
Collapse
|
13
|
Wright WC, Chenge J, Chen T. Structural Perspectives of the CYP3A Family and Their Small Molecule Modulators in Drug Metabolism. LIVER RESEARCH 2019; 3:132-142. [PMID: 32789028 PMCID: PMC7418881 DOI: 10.1016/j.livres.2019.08.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Cytochrome P450 enzymes function to catalyze a wide range of reactions, many of which are critically important for drug response. Members of the human cytochrome P450 3A (CYP3A) family are particularly important in drug clearance, and they collectively metabolize more than half of all currently prescribed medications. The ability of these enzymes to bind a large and structurally diverse set of compounds increases the chances of their modulating or facilitating drug metabolism in unfavorable ways. Emerging evidence suggests that individual enzymes in the CYP3A family play discrete and important roles in catalysis and disease progression. Here we review the similarities and differences among CYP3A enzymes with regard to substrate recognition, metabolism, modulation by small molecules, and biological consequence, highlighting some of those with clinical significance. We also present structural perspectives to further characterize the basis of these comparisons.
Collapse
Affiliation(s)
- William C. Wright
- Department of Chemical Biology and Therapeutics, St. Jude Children’s Research Hospital, Memphis, Tennessee 38105, USA
- Integrated Biomedical Sciences Program, University of Tennessee Health Science Center, Memphis, Tennessee 38163, USA
| | - Jude Chenge
- Integrated Biomedical Sciences Program, University of Tennessee Health Science Center, Memphis, Tennessee 38163, USA
| | - Taosheng Chen
- Department of Chemical Biology and Therapeutics, St. Jude Children’s Research Hospital, Memphis, Tennessee 38105, USA
- Integrated Biomedical Sciences Program, University of Tennessee Health Science Center, Memphis, Tennessee 38163, USA
- Corresponding author: Taosheng Chen, Department of Chemical Biology and Therapeutics, MS 1000, St. Jude Children’s Research Hospital, 262 Danny Thomas Place, Memphis, TN 38105, USA. Tel: (901) 595-5937; Fax: (901) 595-5715;
| |
Collapse
|
14
|
Abstract
PURPOSE OF REVIEW Due to continuous development of new drugs and better treatment strategies, survival of patients with cystic fibrosis has changed dramatically. Recently, targeted therapy of cystic fibrosis transmembrane conductance regulator (CFTR) modulators have become available. Despite these promising developments, treatment of this complex multiorgan disease constitutes a high and variable amount of other drugs. Complications of pharmacotherapeutic treatment are, therefore, expected to become more prevalent. This gives cause to review drug-related side effects in this new era in cystic fibrosis treatment. RECENT FINDINGS We will discuss cystic fibrosis-related pharmacotherapies with a focus on indication of treatment, side effects and their complications, drug--drug interactions, and options to monitor and prevent drug-induced toxicity. Many recent publications about pharmacotherapy in cystic fibrosis, focus on antifungal therapy and CFTR modulators. We will give an overview of the most important studies. SUMMARY With increased life expectancy which is, in part, because of better treatment options, the burden of pharmacotherapy in cystic fibrosis patients will increase. This has a high impact on quality of life as pharmacotherapy is time consuming and may cause side effects. Therefore, it is very important to be aware of possible pharmacotherapy-related side effects and their complications, drug--drug interactions, and options to monitor and prevent drug-induced toxicity.
Collapse
|
15
|
Liddy AM, McLaughlin G, Schmitz S, D'Arcy DM, Barry MG. The pharmacokinetic interaction between ivacaftor and ritonavir in healthy volunteers. Br J Clin Pharmacol 2017; 83:2235-2241. [PMID: 28477428 DOI: 10.1111/bcp.13324] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Revised: 04/13/2017] [Accepted: 04/27/2017] [Indexed: 11/28/2022] Open
Abstract
AIMS The aim of this study was to determine the pharmacokinetic interaction between ivacaftor and ritonavir. METHODS A liquid chromatography mass spectrometry (LC-MS) method was developed for the measurement of ivacaftor in plasma. An open-label, sequential, cross-over study was conducted with 12 healthy volunteers. Three pharmacokinetic profiles were assessed for each volunteer: ivacaftor 150 mg alone (study A), ivacaftor 150 mg plus ritonavir 50 mg daily (study B), and ivacaftor 150 mg plus ritonavir 50 mg daily after two weeks of ritonavir 50 mg daily (study C). RESULTS Addition of ritonavir 50 mg daily to ivacaftor 150 mg resulted in significant inhibition of the metabolism of ivacaftor. Area under the plasma concentration-time curve from time 0 to infinity (AUC0-inf obv ) increased significantly in both studies B and C compared to study A (GMR [95% CI] 19.71 [13.18-31.33] and 19.77 [14.0-27.93] respectively). Elimination half-life (t1/2 ) was significantly longer in both studies B and C compared to study A (GMR [95% CI] 11.14 [8.72-13.62] and 9.72 [6.68-12.85] respectively). There was no significant difference in any of the pharmacokinetic parameters between study B and study C. CONCLUSION Ritonavir resulted in significant inhibition of the metabolism of ivacaftor. These data suggest that ritonavir may be used to inhibit the metabolism of ivacaftor in patients with cystic fibrosis (CF). Such an approach may increase the effectiveness of ivacaftor in 'poor responders' by maintaining higher plasma concentrations. It also has the potential to significantly reduce the cost of ivacaftor therapy.
Collapse
Affiliation(s)
- Anne Marie Liddy
- Department of Pharmacology and Therapeutics, Trinity College Dublin, Ireland
| | - Gavin McLaughlin
- Department of Pharmacology and Therapeutics, Trinity College Dublin, Ireland
| | | | - Deirdre M D'Arcy
- School of Pharmacy and Pharmaceutical Sciences, Trinity College Dublin, Ireland
| | - Michael G Barry
- Department of Pharmacology and Therapeutics, Trinity College Dublin, Ireland
| |
Collapse
|