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Nielsen HK, DeChiaro S, Goldman B. Evaluation of Consistency of Treatment Response Across Regions-the LEADER Trial in Relation to the ICH E17 Guideline. Front Med (Lausanne) 2021; 8:662775. [PMID: 34136501 PMCID: PMC8201994 DOI: 10.3389/fmed.2021.662775] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Accepted: 05/10/2021] [Indexed: 01/05/2023] Open
Abstract
The US Food and Drug Administration in 2008 required new type 2 diabetes (T2D) medications to be subject to cardiovascular outcomes safety requirements. Accordingly, the global LEADER trial investigated cardiovascular outcomes of T2D treatment with liraglutide, a glucagon-like peptide-1 receptor agonist. LEADER (NCT01179048) was a multiregional clinical trial (MRCT) conducted from 2010 to 2016, thus completed before publication of the International Council for Harmonization (ICH) E17 guideline on MRCTs in 2017. Novo Nordisk pre-specified analysis of regional cardiovascular outcomes of LEADER participants. This paper assesses the pre-specified regional outcomes based on the ICH E17 guidelines on consistency evaluation. Regional LEADER participant numbers were broadly aligned with ICH E17 guidance and equally balanced across Europe, Asia, North America, and rest of the world. Overall primary major adverse cardiovascular events (MACE) composite outcome for the trial: hazard ratio (HR) (95% CI) 0.87 (0.78; 0.97); regional results varied, ranging from HR (95% CI) 0.62 (0.37; 1.04) (Asia) to 1.01 (0.84; 1.22) (North America). However, pre-specified Cox proportional-hazard regression analyses did not show clear evidence of interaction between regions and primary outcome (p = 0.20). Furthermore, post hoc analysis of the US population in the North American region found that adjusting for extrinsic or intrinsic factors did not account for this difference [HR (95% CI) 1.03 (0.84; 1.25)]. LEADER data evaluation demonstrated general consistency in cardiovascular safety across regions, except for US participants. Discrepancies in the North American region may relate to drug exposure or chance, but, as these were post hoc findings, the overall primary result is valid, aligned with ICH E17 guidelines.
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Marchand L, Luyton C, Bernard A. Glucagon-like peptide-1 (GLP-1) receptor agonists in type 2 diabetes and long-term complications: FOCUS on retinopathy. Diabet Med 2021; 38:e14390. [PMID: 32799379 DOI: 10.1111/dme.14390] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Revised: 07/16/2020] [Accepted: 08/12/2020] [Indexed: 01/22/2023]
Affiliation(s)
- L Marchand
- Department of Endocrinology and Diabetes, Centre Hospitalier Saint Joseph Saint Luc, Lyon
| | - C Luyton
- Department of Endocrinology and Diabetes, Centre Hospitalier Saint Joseph Saint Luc, Lyon
| | - A Bernard
- Department of Ophthalmology, Hospices Civils de Lyon, Centre Hospitalier Lyon-Sud, Pierre-Bénite
- Department of Ophthalmology, Centre Hospitalier Saint Joseph Saint Luc, Lyon, France
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Mann JFE, Fonseca V, Mosenzon O, Raz I, Goldman B, Idorn T, von Scholten BJ, Poulter NR. Effects of Liraglutide Versus Placebo on Cardiovascular Events in Patients With Type 2 Diabetes Mellitus and Chronic Kidney Disease. Circulation 2019; 138:2908-2918. [PMID: 30566006 PMCID: PMC6296845 DOI: 10.1161/circulationaha.118.036418] [Citation(s) in RCA: 62] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
BACKGROUND LEADER trial (Liraglutide Effect and Action in Diabetes: Evaluation of CV Outcome Results) results demonstrated cardiovascular benefits for patients with type 2 diabetes mellitus at high cardiovascular risk on standard of care randomized to liraglutide versus placebo. The effect of glucagon-like peptide-1 receptor agonist liraglutide on cardiovascular events and all-cause mortality in patients with type 2 diabetes mellitus and chronic kidney disease is unknown. Liraglutide's treatment effects in patients with and without kidney disease were analyzed post hoc. METHODS Patients were randomized (1:1) to liraglutide or placebo, both in addition to standard of care. These analyses assessed outcomes stratified by baseline estimated glomerular filtration rate (eGFR; <60 versus ≥60 mL/min/1.73 m2) and baseline albuminuria. The primary outcome (composite of cardiovascular death, nonfatal myocardial infarction, or nonfatal stroke) and secondary outcomes, including all-cause mortality and individual components of the primary composite outcome, were analyzed using Cox regression. RESULTS Overall, 2158 and 7182 patients had baseline eGFR <60 or ≥60 mL/min/1.73 m2, respectively. In patients with eGFR <60 mL/min/1.73 m2, risk reduction for the primary composite cardiovascular outcome with liraglutide was greater (hazard ratio [HR], 0.69; 95% CI, 0.57-0.85) versus those with eGFR ≥60 mL/min/1.73 m2 (HR, 0.94; 95% CI, 0.83-1.07; interaction P=0.01). There was no consistent effect modification with liraglutide across finer eGFR subgroups (interaction P=0.13) and when analyzing eGFR as a continuous variable (interaction P=0.61). Risk reductions in those with eGFR <60 versus ≥60 mL/min/1.73 m2 were as follows: for nonfatal myocardial infarction, HR, 0.74; 95% CI, 0.55-0.99 versus HR, 0.93; 95% CI, 0.77-1.13; for nonfatal stroke, HR, 0.51; 95% CI, 0.33-0.80 versus HR, 1.07; 95% CI, 0.84-1.37; for cardiovascular death, HR, 0.67; 95% CI, 0.50-0.90 versus HR, 0.84; 95% CI, 0.67-1.05; for all-cause mortality, HR, 0.74; 95% CI, 0.60-0.92 versus HR, 0.90; 95% CI, 0.75-1.07. Risk reduction for the primary composite cardiovascular outcome was not different for those with versus without baseline albuminuria (HR, 0.83; 95% CI, 0.71-0.97; and HR, 0.92; 95% CI, 0.79-1.07, respectively; interaction P=0.36). CONCLUSIONS Liraglutide added to standard of care reduced the risk for major cardiovascular events and all-cause mortality in patients with type 2 diabetes mellitus and chronic kidney disease. These results appear to apply across the chronic kidney disease spectrum enrolled. CLINICAL TRIAL REGISTRATION URL: https://www.clinicaltrials.gov/ . Unique identifier: NCT01179048.
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Affiliation(s)
- Johannes F E Mann
- Kuratorium für Dialyse Kidney Center, Munich, Germany (J.F.E.M.).,Department of Nephrology, Friedrich Alexander University of Erlangen, Germany (J.F.E.M.)
| | - Vivian Fonseca
- Division of Endocrinology, Tulane University Health Sciences Center, School of Medicine, New Orleans, LA (V.F.)
| | - Ofri Mosenzon
- Diabetes Unit, Hadassah Hebrew University Hospital, Jerusalem, Israel (O.M., I.R.)
| | - Itamar Raz
- Diabetes Unit, Hadassah Hebrew University Hospital, Jerusalem, Israel (O.M., I.R.)
| | - Bryan Goldman
- Novo Nordisk A/S, Søborg, Denmark (B.G., T.I., B.J.v.S.)
| | - Thomas Idorn
- Novo Nordisk A/S, Søborg, Denmark (B.G., T.I., B.J.v.S.)
| | | | - Neil R Poulter
- Imperial Clinical Trials Unit, Imperial College London, UK (N.R.P.)
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Verma S, Bain SC, Monk Fries T, Mazer CD, Nauck MA, Pratley RE, Rasmussen S, Saevereid HA, Zinman B, Buse JB. Duration of diabetes and cardiorenal efficacy of liraglutide and semaglutide: A post hoc analysis of the LEADER and SUSTAIN 6 clinical trials. Diabetes Obes Metab 2019; 21:1745-1751. [PMID: 30851070 PMCID: PMC6619033 DOI: 10.1111/dom.13698] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Revised: 03/04/2019] [Accepted: 03/06/2019] [Indexed: 01/16/2023]
Abstract
Cardiovascular risk reduction with liraglutide and semaglutide in patients with type 2 diabetes was demonstrated in the LEADER (ClinicalTrials.gov: NCT01179048) and SUSTAIN 6 (ClinicalTrials.gov: NCT01720446) cardiovascular outcome trials. This post hoc analysis assessed the impact of diabetes duration (<5, 5 to <15, 15 to <25 and ≥25 years at baseline) on cardiorenal efficacy of these human glucagon-like peptide-1 analogues using a Cox proportional hazards model. Proportions of patients in the LEADER trial across diabetes duration strata were 15% (<5 years, n = 1377), 50% (5 to <15 years, n = 4692), 27% (15 to <25 years, n = 2504) and 8% (≥25 years, n = 748); corresponding proportions in the SUSTAIN-6 trial were 13% (<5 years, n = 422), 48% (5 to <15 years, n = 1582), 30% (15 to <25 years, n = 977) and 10% (≥25 years, n = 316). Overall, longer diabetes duration was associated with higher age; higher prevalence of females; history of ischaemic stroke, peripheral arterial disease and insulin use; and inferior renal function. There was an increased frequency of major adverse cardiovascular events (MACE), expanded MACE and nephropathy events with increasing diabetes duration. Liraglutide and semaglutide consistently reduced the risk of cardiorenal outcomes across categories of diabetes duration (P-interaction was not significant for all endpoints analysed).
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Affiliation(s)
- Subodh Verma
- Department of Anesthesia, Division of Cardiac Surgery, St. Michael's Hospital and University of TorontoTorontoOntarioCanada
| | - Stephen C. Bain
- Institute of Life Science, Swansea University Medical SchoolSwanseaUK
| | | | - C. David Mazer
- Department of Anesthesia, Division of Cardiac Surgery, St. Michael's Hospital and University of TorontoTorontoOntarioCanada
| | - Michael A. Nauck
- Diabetes Center Bochum‐Hattingen, St Josef Hospital (Ruhr‐Universität Bochum)BochumGermany
| | - Richard E. Pratley
- Florida Hospital Translational Research Institute for Metabolism and DiabetesOrlandoFlorida
| | | | | | - Bernard Zinman
- Lunenfeld–Tanenbaum Research Institute, Mt. Sinai HospitalUniversity of TorontoTorontoOntarioCanada
| | - John B. Buse
- Department of MedicineUniversity of North Carolina School of MedicineChapel HillNorth Carolina
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Nauck MA, Buse JB, Mann JFE, Pocock S, Bosch‐Traberg H, Frimer‐Larsen H, Ye Q, Gray A. Health-related quality of life in people with type 2 diabetes participating in the LEADER trial. Diabetes Obes Metab 2019; 21:525-532. [PMID: 30260088 PMCID: PMC6587748 DOI: 10.1111/dom.13547] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Revised: 09/07/2018] [Accepted: 09/23/2018] [Indexed: 12/19/2022]
Abstract
AIMS To assess health-related quality of life (HRQoL) in people with type 2 diabetes (T2D) participating in the LEADER cardiovascular outcomes trial using the five-dimension European Quality of Life questionnaire (EQ-5D). MATERIALS AND METHODS The EQ-5D was administered every 12 months in a subset of patients from Canada, Denmark, Germany, Ireland, Italy, Netherlands, Spain, Sweden, the United Kingdom and the United States. We compared changes in utility index scores and visual analogue scale (VAS) scores from baseline to 36 months in participants treated with liraglutide and placebo. We also assessed which complications had the greatest impact on quality of life. RESULTS At 36 months, less deterioration in EQ-5D utility index score was seen in the liraglutide group (-0.058) than in the placebo group (-0.082; estimated treatment difference [ETD] 0.023, 95% confidence interval [CI] 0.004;0.043; P = 0.020). A smaller decrease in EQ-5D VAS score was also demonstrated in the liraglutide group (-3.51) vs. the placebo group (-5.45; ETD 1.94, 95% CI 0.32;3.57; P = 0.019). The benefits of liraglutide treatment compared with placebo were driven primarily by shifts in the domains of mobility and self-care. The most influential events contributing to poorer HRQoL were stroke, heart failure, malignant neoplasm and confirmed hypoglycaemia. CONCLUSIONS Liraglutide demonstrated a modest but significant benefit in patient-reported health status using the EQ-5D, compared with placebo. This benefit may be of clinical relevance and requires further study.
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Affiliation(s)
- Michael A. Nauck
- Diabetes Centre Bochum‐Hattingen, Medical Department ISt. Josef‐Hospital, Ruhr‐UniversityBochumGermany
| | - John B. Buse
- Division of Endocrinology, Department of MedicineUniversity of North Carolina School of MedicineChapel HillNorth Carolina
| | - Johannes F. E. Mann
- KfH Kidney CentreMunichGermany
- Department of NephrologyFriedrich Alexander University of ErlangenErlangenGermany
| | - Stuart Pocock
- Department of Medical StatisticsFaculty of Epidemiology and Population Health, London School of Hygiene and Tropical MedicineLondonUK
| | | | | | - Qing Ye
- Novo NordiskBagsvaerdDenmark
| | - Alastair Gray
- Nuffield Department of Population HealthHealth Economics Research Centre, University of OxfordOxfordUK
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Abstract
The prevalence of heart failure (HF) is increasing in patients with type 2 diabetes (T2D), and glucose-lowering agents have distinctive effects on the risk of developing HF that requires hospitalization. Such an increased risk has been consistently reported with thiazolidinediones (glitazones) and perhaps also with the dipeptidyl peptidase (DPP)-4 inhibitor saxagliptin (at least in SAVOR - TIMI 53), whereas a markedly decreased risk was highlighted with the sodium - glucose cotransporter type 2 (SGLT2) inhibitor empagliflozin in EMPA-REG OUTCOME. Yet, the effects of glucagon-like peptide-1 receptor agonists (GLP-1RAs) on myocardial function remain controversial. Whereas some promising observations have been reported in various animal models, the effects of GLP-1RAs on myocardial function in humans are more heterogeneous, while the positive effect on left ventricular ejection fraction (LVEF), if any, appears to be inconsistent and rather modest in most patients with HF. However, no increased risk of hospitalization for HF has been reported with GLP-1RAs in meta-analyses of phase-II/III trials (exenatide, albiglutide, dulaglutide, liraglutide), demonstrating the safety of this pharmacological class, and such findings have been confirmed by three large prospective cardiovascular outcome trials (ELIXA with lixisenatide, LEADER with liraglutide and SUSTAIN-6 with semaglutide). In particular, LEADER reported a trend towards a reduction in HF hospitalization (-13%, P = 0.14), together with a significant reduction in cardiovascular and all-cause mortality in patients with T2D at risk of cardiovascular disease. These results are reassuring in the face of the somewhat negative results of the FIGHT trial, which evaluated the effects of liraglutide in patients with advanced HF and low LVEF, such that further studies and caution are now required when using this agent to treat such patients in clinical practice.
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Affiliation(s)
- André J Scheen
- Division of Diabetes, Nutrition and Metabolic Disorders, Department of Medicine, CHU Sart Tilman (B35), B-4000 Liege 1, Belgium; Clinical Pharmacology Unit, CHU Liège, Center for Interdisciplinary Research on Medicines (CIRM), University of Liège, Liège, Belgium.
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Abstract
PURPOSE OF REVIEW We review the cardiovascular and renal outcomes and safety of newer anti-diabetic medications in high-risk patients. We examine the outcomes of the IRIS, EMPA-REG OUTCOME, CANVAS, LEADER, SAVOR-TIMI 53, and EXAMINE trials demonstrating the cardiovascular and renal benefits of thiazolidinediones, SGLT2 inhibitors, GLP-1 agonists, and DPP-4 inhibitors. RECENT FINDINGS Diabetes mellitus is a leading risk factor for cardiovascular disease with rising prevalence and disease burden. The microvascular and macrovascular complications of diabetes are well-recognized and include increased risk of cardiovascular disease, myocardial infarction, and stroke. Newer diabetes medications have demonstrated significant cerebrovascular, cardiovascular, renal, and mortality benefits in high risk patients with diabetes. In addition to their glucose-lowering effects, the thiazolidinedione pioglitazone, SGLT2 inhibitors, GLP-1 agonist, and DPP-4 inhibitors have demonstrated significant cerebrovascular, cardiovascular, renal, and mortality effects. The outcomes and safety data of newer diabetes medications from recent trials demonstrate cardiovascular and mortality effects with significant implications for clinical practice.
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Affiliation(s)
- Lima Lawrence
- Cleveland Clinic, Department of Endocrinology, Diabetes and Metabolism, 9500 Euclid Ave. F20, Cleveland, OH, 44195, USA
| | - Venu Menon
- Cleveland Clinic, Department of Cardiovascular Medicine, 9500 Euclid Ave. J1-5, Cleveland, OH, 44195, USA
| | - Sangeeta Kashyap
- Cleveland Clinic, Department of Endocrinology, Diabetes and Metabolism, 9500 Euclid Ave. F20, Cleveland, OH, 44195, USA.
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Pfaller MA, Mendes RE, Streit JM, Hogan PA, Flamm RK. Five-Year Summary of In Vitro Activity and Resistance Mechanisms of Linezolid against Clinically Important Gram-Positive Cocci in the United States from the LEADER Surveillance Program (2011 to 2015). Antimicrob Agents Chemother 2017; 61:e00609-17. [PMID: 28483950 PMCID: PMC5487612 DOI: 10.1128/aac.00609-17] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Accepted: 04/27/2017] [Indexed: 11/20/2022] Open
Abstract
This report describes linezolid susceptibility testing results for 6,741 Gram-positive pathogens from 60 U.S. sites collected during 2015 for the LEADER Program. In addition, the report summarizes linezolid in vitro activity, resistance mechanisms, and molecular typing obtained for 2011 to 2015. During 2015, linezolid showed potent activity in testing against Staphylococcus aureus, inhibiting >99.9% of 3,031 isolates at ≤2 µg/ml. Similarly, linezolid showed coverage against 99.2% of coagulase-negative staphylococci, 99.7% of enterococci, and 100.0% of Streptococcus pneumoniae, virdans group, and beta-hemolytic streptococcus isolates tested. The overall linezolid resistance rate remained a modest <1% from 2011 to 2015. Staphylococci, especially Staphylococcus epidermidis, showed a range of linezolid resistance mechanisms. Increased annual trends for the presence of cfr among Staphylococcus aureus isolates were not observed, but 64.3% (9/14) of the isolates with decreased susceptibility (MIC, ≥4 µg/ml) to linezolid carried this transferrable gene (2011 to 2015). The cfr gene was detected in 21.9% (7/32) of linezolid-resistant staphylococci other than S. aureus from 2011 to 2015. The optrA gene was noted in half (2/4) of the population of linezolid-nonsusceptible Enterococcus faecalis isolates from 2011 to 2015, while linezolid-nonsusceptible Enterococcus faecium isolates showed alterations predominantly (16/16) in the 23S rRNA gene (G2576T). This report confirms a long record of linezolid activity against Gram-positive isolates in the United States since regulatory approval in 2000 and reports the oxazolidinones evolving resistance mechanisms.
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Affiliation(s)
- Michael A Pfaller
- JMI Laboratories, North Liberty, Iowa, USA
- University of Iowa, Iowa City, Iowa, USA
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Abstract
INTRODUCTION Liraglutide is a GLP-1 RA that is an option for treatment of T2DM. Typical of all new glucose-lowering agents, its CV safety profile is of great interest. Areas covered: This article outlines the efficacy of the GLP-1 RA liraglutide from RCTs, moving through the pivotal phase 3 LEAD trials, and subsequent meta-analyses to assess CV safety. This review describes evolution of regulatory requirements to obtain safety information through dedicated CVOTs. Expert opinion: Since the FDA mandated that CV outcomes for new diabetes therapies should be assessed via a dedicated CVOT, opinion of their utility in T2DM evolved from cynicism through to enthusiasm. In LEADER, liraglutide became the second modern glucose-lowering agent to demonstrate significant CV benefit. CVOTs are now providing important answers, highlighting the CV benefits of modern glucose-lowering agents, but also raising several questions, notably whether the effects seen with liraglutide and empagliflozin are class-effects or are unique to these molecules. Furthermore it is unknown if these results in patients with high CV risk are applicable to all patients with T2DM, and should be incorporated into new treatment guidelines. In our view it's prudent to suggest that CVOT findings cannot currently be extrapolated to the whole T2DM population.
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Affiliation(s)
| | - Steve Bain
- a Singleton Hospital , Swansea UK.,b Institute of Life Science, Swansea University , UK
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Abstract
The large multinational, randomised, double-blind LEADER (Liraglutide Effect and Action in Diabetes: Evaluation of Cardiovascular Outcome Results - A Long Term Evaluation) trial recently reported the cardiovascular (CV) benefits achieved with liraglutide therapy in type 2 diabetes mellitus (T2DM). This editorial analyses the primary and secondary CV outcomes (CVO) results of the LEADER trial, and discusses the impact these will have on clinical practice of diabetes in specific, and medicine in general. It delves into the evolution of clinical and biochemical outcomes used in diabetes, and discusses the role of liraglutide in shaping future outcomes. The editorial describes the potential role of liraglutide in primary, secondary and tertiary prevention of CV disease (CVD), and suggests exaptation of this molecule for use in cardiology, nephrology and neurology.
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Affiliation(s)
- Sanjay Kalra
- Department of Endocrinology, Bharti Hospital, Karnal, India
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Mendes RE, Deshpande LM, Jones RN. Linezolid update: stable in vitro activity following more than a decade of clinical use and summary of associated resistance mechanisms. Drug Resist Updat 2014; 17:1-12. [PMID: 24880801 DOI: 10.1016/j.drup.2014.04.002] [Citation(s) in RCA: 155] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Linezolid, approved for clinical use since 2000, has become an important addition to the anti-Gram-positive infection armamentarium. This oxazolidinone drug has in vitro and in vivo activity against essentially all Gram-positive organisms, including methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE). The in vitro activity of linezolid was well documented prior to its clinical application, and several ongoing surveillance studies demonstrated consistent and potent results during the subsequent years of clinical use. Emergence of resistance has been limited and associated with invasive procedures, deep organ involvement, presence of foreign material and mainly prolonged therapy. Non-susceptible organisms usually demonstrate alterations in the 23S rRNA target, which remain the main resistance mechanism observed in enterococci; although a few reports have described the detection of cfr-mediated resistance in Enterococcus faecalis. S. aureus isolates non-susceptible to linezolid remain rare in large surveillance studies. Most isolates harbour 23S rRNA mutations; however, cfr-carrying MRSA isolates have been observed in the United States and elsewhere. It is still uncertain whether the occurrences of such isolates are becoming more prevalent. Coagulase-negative isolates (CoNS) resistant to linezolid were uncommon following clinical approval. Surveillance data have indicated that CoNS isolates, mainly Staphylococcus epidermidis, currently account for the majority of Gram-positive organisms displaying elevated MIC results to linezolid. In addition, these isolates frequently demonstrate complex and numerous resistance mechanisms, such as alterations in the ribosomal proteins L3 and/or L4 and/or presence of cfr and/or modifications in 23S rRNA. The knowledge acquired during the past decades on this initially used oxazolidinone has been utilized for developing new candidate agents, such as tedizolid and radezolid, and as linezolid patents soon begin to expire, generic brands will certainly become available. These events will likely establish a new chapter for this successful class of antimicrobial agents.
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Affiliation(s)
| | | | - Ronald N Jones
- JMI Laboratories, North Liberty, IA 52317, USA; Tufts University School of Medicine, Boston, MA 02111, USA
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