Telavancin: a novel lipoglycopeptide for serious Gram-positive infections

Telavancin, a once-daily dosing lipoglycopeptide derived from vancomycin, has a broad-spectrum microbiologic activity against Gram-positive bacteria, including vancomycin-resistant staphylococci. Telavancin displays a dual mode of action and a rapid bactericidal killing. The in vitro activity of telavancin is superior to vancomycin and comparable with, or greater than, linezolid, daptomycin and other novel lipoglycopeptides. Telavancin is effective against Gram-positive pathogens in animal models of soft tissue infections and deep-seated infections including endocarditis, pneumonia and bacteremia. Clinical experience with telavancin in Phase II and III studies for complicated skin and skin structure infections have demonstrated similar efficacy and tolerability compared with standard anti-staphylococcal β-lactams and vancomycin. Telavancin is in Phase III studies for nosocomial pneumonia. Telavancin seems to be promising as a novel agent for empiric therapy or as an alternative agent in serious infections caused by clinically important resistant Gram-positive pathogens such as methicillin-resistant Staphylococcus aureus, vancomycin intermediate-susceptible S. aureus, vancomycin-resistant S. aureus and vancomycin-resistant enterococci.     

Pharmacodynamics,pharmacokinetics and clinical efficacy of telavancin in the treatment of pneumonia

Introduction: Telavancin is a novel lipoglycopeptide derivative of vancomycin that has activity against Gram-positive aerobic and anerobic bacteria, for the treatment of serious infections, including complicated skin and skin structure infections (cSSSI) and pneumonia.

Areas covered: This article was compiled through searches on telavancin up to December 2015 in the PubMed and the clinicaltrials.gov databases; the FDA and European Medicine Agency (EMA) websites. In our review, particular attention was paid to those articles that reviewed the pharmacokinetic characteristics of the drug and animal models of infection. We also searched for evidence of the efficacy of telavancin as demonstrated in clinical trials, safety and tolerability data and have compiled a summary of clinical trials on telavancin in pneumonia.

Expert opinion: Telavancin is approved in Europe and the USA for the treatment of nosocomial pneumonia caused by methicillin resistant Staphylococcus aureus when other alternatives are not suitable.     

Telavancin: a novel lipoglycopeptide for serious gram-positive infections

Telavancin, a once-daily dosing lipoglycopeptide derived from vancomycin, has a broad-spectrum microbiologic activity against gram-positive bacteria, including vancomycin-resistant staphylococci. Telavancin displays a dual mode of action and a rapid bactericidal killing. The in vitro activity of telavancin is superior to vancomycin and comparable with, or greater than, linezolid, daptomycin and other novel lipoglycopeptides. Telavancin is effective against gram-positive pathogens in animal models of soft tissue infections and deep-seated infections including endocarditis, pneumonia and bacteremia. Clinical experience with telavancin in Phase II and III studies for complicated skin and skin structure infections have demonstrated similar efficacy and tolerability compared with standard anti-staphylococcal beta-lactams and vancomycin. Telavancin is in Phase III studies for nosocomial pneumonia. Telavancin seems to be promising as a novel agent for empiric therapy or as an alternative agent in serious infections caused by clinically important resistant gram-positive pathogens such as methicillin-resistant Staphylococcus aureus, vancomycin intermediate-susceptible S. aureus, vancomycin-resistant S. aureus and vancomycin-resistant enterococci.     

A new lipoglycopeptide: telavancin

The increase in infections caused by resistant Gram-positive organisms has led to an urgent need for new antibiotics. Telavancin is a rapidly bactericidal lipoglycopeptide with multiple mechanisms of action, including concentration-dependent inhibition of bacterial cell wall synthesis and disruption of the functional integrity of the cell membrane. Telavancin is active against a wide variety of Gram-positive organisms including Staphylococcus aureus with resistance to methicillin, reduced susceptibility to vancomycin, and full resistance to vancomycin. Telavacin is approximately 90% protein bound; it has a serum half-life of around 8 h and a prolonged postantibiotic effect, allowing once daily administration. Telavancin is eliminated principally through the urine, requiring dose adjustment in patients with renal impairment. The efficacy and safety of telavancin was demonstrated in a large program of patients with complicated skin and skin structure infections. Development of resistance has not been detected in clinical strains. Adverse events include taste disturbance, nausea and vomiting; a small proportion of patients experienced reversible increase in serum creatinine. Two large Phase III studies in patients with healthcare associated pneumonia were recently completed. Telavancin has the potential to become an important therapeutic option to treat serious infections produced by resistant Gram-positive cocci, particularly those caused by methicillin-resistant S. aureus.     

Use of daptomycin for treatment of Staphylococcus aureus infections

Gram-positive bacteria such as Staphylococcus aureus are important human pathogens. An increasing proportion of S. aureus are methicillin resistant. For decades, methicillin-resistant S. aureus infections have been treated with vancomycin, but susceptibility is decreasing, and tissue penetration and safety profile (especially nephrotoxicity) is not ideal. Consequently, there is a great need for the development of antibiotics with demonstrated efficacy and safety for infections caused by S. aureus and other Gram-positive pathogens. One such antibiotic is daptomycin, which has a unique mechanism of action and potent, rapid bactericidal activity, without causing cell lysis. Daptomycin has demonstrated significant efficacy in the treatment of complicated skin and skin structure infections, as well as methicillin-susceptible and methicillin-resistant S. aureus bacteremia, including right-sided endocarditis. Other attributes include an excellent safety profile, low potential for resistance, and once-daily dosing.     

Review of dalbavancin,a novel semisynthetic lipoglycopeptide

Dalbavancin is a semisynthetic lipoglycopeptide that is derived from teicoplanin with an extended half-life that enables once-weekly dosing. It has potent in vitro activity against most Gram-positive organisms, with lower minimum inhibitory concentration values than vancomycin and other investigational lipoglycopeptides. Dalbavancin is active against multi-drug-resistant pathogens such as methicillin-resistant Staphylococcus aureus and vancomycin-resistant enterococci, except for strains exhibiting vanA resistance. Several Phase II and III trials have established similar efficacy and safety of dalbavancin with comparator agents in the treatment of complicated skin and skin structure infections and in catheter-related bloodstream infections. Dalbavancin may serve as an appealing alternative agent in the treatment of Gram-positive infections, especially with its convenient once-weekly regimen.     

A new lipoglycopeptide: telavancin

The increase in infections caused by resistant Gram-positive organisms has led to an urgent need for new antibiotics. Telavancin is a rapidly bactericidal lipoglycopeptide with multiple mechanisms of action, including concentration-dependent inhibition of bacterial cell wall synthesis and disruption of the functional integrity of the cell membrane. Telavancin is active against a wide variety of Gram-positive organisms including Staphylococcus aureus with resistance to methicillin, reduced susceptibility to vancomycin, and full resistance to vancomycin. Telavacin is approximately 90% protein bound; it has a serum half-life of around 8 h and a prolonged postantibiotic effect, allowing once daily administration. Telavancin is eliminated principally through the urine, requiring dose adjustment in patients with renal impairment. The efficacy and safety of telavancin was demonstrated in a large program of patients with complicated skin and skin structure infections. Development of resistance has not been detected in clinical strains. Adverse events include taste disturbance, nausea and vomiting; a small proportion of patients experienced reversible increase in serum creatinine. Two large Phase III studies in patients with healthcare associated pneumonia were recently completed. Telavancin has the potential to become an important therapeutic option to treat serious infections produced by resistant Gram-positive cocci, particularly those caused by methicillin-resistant S. aureus.     

A comparison of available and investigational antibiotics for complicated skin infections and treatment-resistant Staphylococcus aureus and enterococcus

This article compares vancomycin, teicoplanin, quinupristin-dalfopristin, linezolid, daptomycin, tigecyline, dalbavancin, telavancin, ceftobiprole, oritavancin, and ramoplanin for the treatment of complicated skin and skin structure infections (cSSSI), methicillin-resistant Staphylococcus aureus (MRSA), enterococcus, and vancomycin-resistant enterococcus. Vancomycin, a glycopeptide antibiotic, is administered intravenously, and is the mainstay of treatment for MRSA and cSSSI. While not available in the U.S., teicoplanin, another glycopeptide antibiotic, can be administered intramuscularly and has simpler dosing and monitoring requirements than vancomycin. Quinupristin/dalfopristin treats vancomycin-resistant Enterococcus faecium (VREF) infections but inhibits cytochrome P450 A3P4, and has only modest activity against MRSA pneumonia. Daptomycin effectively treats cSSSI but not pneumonia caused by MRSA, and is effective against all strains of Staphylococcus. Linezolid, available orally and intravenously, is approved to treat community-acquired and nosocomial pneumonia, cSSSI, and infections caused by MRSA and vancomycin-resistant enterococci including infections with concurrent bacteraemia and VREE Tigecycline, a glycylcycline derived from minocycline, has been approved by the FDA to treat cSSSI and complicated intraabdominal infections, and might be effective against Acinetobacter baumannii; its primary side effect is digestive upset. Dalbavancin, effective against MRSA and administered intravenously once weekly, possesses coverage similar to vancomycin. Telavancin deploys multiple mechanisms of action and is effective against MRSA and Gram-positive bacteria resistant to vancomycin. Ceftobiprole, a cephalosporin effective against MRSA, has few side effects. Oritavancin demonstrates similar activity to vancomycin but possesses extended activity against vancomycin-resistant Staphylococcus and enterococci. Ramoplanin, a macrocyclic depsipeptide, is unstable in the bloodstream but can be taken orally to treat Clostridium difficile colitis.     

Glycopeptides in clinical development: pharmacological profile and clinical perspectives

Vancomycin and teicoplanin are the two glycopeptides currently used in the clinics for the treatment of multiresistant infections by Gram-positive organisms. The development of resistance in enterococci and staphylococci has stimulated the search for new derivatives with improved activity, particularly against strains resistant to conventional derivatives. Three of these, obtained by hemi-synthesis starting from natural compounds, are now in clinical development (oritavancin and telavancin, as derivatives of vancomycin; and dalbavancin, as a derivative of teicoplanin). The presence of a lipophilic tail on these molecules results in them having a prolonged half-life. It also modifies their mode of action, conferring to them a concentration-dependent bactericidal activity. Their spectrum of activity includes methicillin-susceptible or methicillin-resistant staphylococci, penicillin-resistant pneumococci and enterococci (including vancomycin-resistant strains for oritavancin and telavancin). Ongoing clinical studies are evaluating the efficacy and safety of these molecules for the treatment of complicated skin and soft tissue infections and bactereamia, in a once-daily (oritavancin, telavancin) or once-weekly (dalbavancin) scheme of administration. Despite these remarkable properties, the use of these potent molecules should be restricted to severe infections by multiresistant organisms to limit the risk of selection of resistance.     

Telavancin: TD 6424, TD-6424

Telavancin [TD-6424, ARBELIC] is an injectable, bactericidal lipoglycopeptide antibacterial that is in clinical development with Theravance (formerly Advanced Medicine) in the US. Telavancin, which was discovered by Theravance through the application of multivalent drug design, has a broad spectrum of activity against Gram-positive pathogens. Telavancin is currently in phase III development for complicated skin and soft tissue infections (including those caused by methicilin-resistant Staphylococcus aureus [MRSA]), nosocomial pneumonia, as well as other Gram-positive pathogens. The antibacterial effects of telavancin are mediated through multiple mechanisms, including inhibition of cell wall (peptidoglycan) synthesis. The drug also produces changes in bacterial cell membrane permeability. The multiple mechanisms of action may be responsible for the low frequency of spontaneous resistance to telavancin. Theravance and Astellas Pharma entered into a licensing agreement for telavancin in November 2005. The two companies will collaborate for the development and commercialisation of the antibacterial agent worldwide, except Japan. Under the terms of the agreement, Astellas will make a 65 million US dollars up-front payment and royalties on global sales to Theravance; in addition, Theravance is eligible to receive 156 million US dollars in clinical and regulatory milestones payments, including 136 million US dollars for completing enrollment, filling and approval of ongoing phase III programmes, and 20 million US dollars if phase III data indicate telavancin's superiority over vancomycin for the treatment of MRSA. Theravance will continue to explore partnering opportunities in the Japanese market. Telavancin was granted fast-track status by the US FDA in March 2005 for the treatment of complicated skin and skin structure infections (cSSSIs), as well as hospital-acquired pneumonia (nosocomial pneumonia). The compound is currently in phase III trials for these indications in the US. Theravance has also conducted two randomised, double-blind phase II trials (FAST and FAST 2) of telavancin in patients with cSSSIs caused by Gram-positive bacteria, in which telavancin (7 or 10 mg/kg) was compared with standard vancomycin therapy. Results showed that while telavancin was comparable to standard therapy overall, telavancin was associated with superior MRSA eradication rates.     

Update on linezolid: the first oxazolidinone antibiotic

Linezolid is the first of an entirely new class of antibiotics, the oxazolidinones, in decades. It has a spectrum of activity against virtually all important Gram-positive pathogens. The unique mechanism of action of linezolid makes cross-resistance with other antimicrobial agents unlikely. Linezolid has both intravenous and oral formulations and the latter is 100% bioavailable. Since its first approval and marketing in March 2000 in the US, linezolid has gained approval for use in many other countries for the treatment of community-acquired and nosocomial pneumonia, complicated and uncomplicated skin and soft-tissue infections, and infections caused by methicillin-resistant Staphylococcus aureus and vancomycin-resistant enterococci, including cases with concurrent bacteraemia. Several earlier comprehensive reviews summarised the chemistry, mechanism of action, pharmacokinetics, clinical efficacy and safety profile of linezolid. The present review provides an update on the latest data regarding the antimicrobial activity of linezolid versus other commonly used agents, the clinical and health-economic outcomes of linezolid versus vancomycin and teicoplanin, and safety issues.     

Management of cSSTIs:the role of daptomycin

ABSTRACT

Background: Skin and soft tissue infections (SSTIs) and complicated SSTIs (cSSTIs), particularly those caused by Gram-positive pathogens, are among the most common human bacterial infections The emergence of resistance to antibiotics such as methicillin and vancomycin has compromised treatment options for these infections and stimulated the search for new antimicrobial therapies. Daptomycin, the first in a class of agents known as cyclic lipopeptides, is a novel antibiotic with potent activity against most Grampositive pathogens, including methicillin‐ resistant Staphylococcus aureus.

Scope: This review examines the novel properties of daptomycin and describes its therapeutic efficacy and tolerability, particularly in the treatment of cSSTIs. The data search strategy included identification of original research papers, review articles, meeting reports and editorials by searches of MEDLINE and references from relevant articles.

Findings: In vitro studies have demonstrated that daptomycin has superior bactericidal activity compared with vancomycin and the newer anti-Gram-positive agents, quinupristin/dalfopristin and linezolid. Robust, randomised, phase III clinical trials have shown daptomycin to be effective and well tolerated for the treatment of cSSTIs caused by Gram-positive bacteria, with equivalent clinical success rates and a similar safety profile to those of comparator agents. Data from these studies suggest a trend toward shorter duration of therapy and faster resolution of symptoms with daptomycin.

Conclusions: Given the pressing need for new antibiotics to combat infections caused by Gram-positive organisms, and to overcome the problem of resistance to conventional antibiotics, daptomycin is a welcome addition to the treatment options for the management of cSSTIs.     

Telavancin: a novel lipoglycopeptide antimicrobial agent.

PURPOSE: The pharmacology, activity, pharmacokinetics, pharmacodynamics, clinical efficacy, safety, dosage, and place in therapy of telavancin are reviewed. SUMMARY: Telavancin is a lipoglycopeptide antimicrobial agent under development for use in the treatment of multidrug-resistant gram-positive infections. Telavancin, like vancomycin, inhibits cell-wall biosynthesis by binding to late-stage cell-wall precursors. However, unlike vancomycin, telavancin also depolarizes the bacterial cell membrane and disrupts its functional integrity. Telavancin has concentration-dependent bactericidal activity and is active against gram-positive aerobic and anaerobic organisms. It is highly protein bound (93%) and has a volume of distribution of 115 mL/kg and a half-life of approximately eight hours. Telavancin is eliminated renally, and a dosage reduction is required in renally impaired patients. Animal models suggest that telavancin may be effective in the treatment of soft-tissue infections, bacteremia, endocarditis, meningitis, and pneumonia caused by gram-positive pathogens. Telavancin was not inferior to standard treatment for complicated skin and soft-tissue infections in two Phase II clinical trials and two Phase III clinical trials. A new drug application has been submitted for this indication, and Phase III trials to evaluate use in hospital-acquired-pneumonia, including infections caused by methicillin-resistant Staphylococcus aureus (MRSA), are planned. Adverse effects include metallic taste, nausea, vomiting, headache, foamy urine, Q-Tc-interval prolongation, hypokalemia, and serum creatinine increases. In trials evaluating telavancin for skin and soft-tissue infections, the dosage was 10 mg/kg i.v. once daily. CONCLUSION: Telavancin is a promising new agent for gram-positive infections and may offer an alternative to vancomycin for MRSA-associated infections.     

Glycopeptides and glycodepsipeptides in clinical development: a comparative review of their antibacterial spectrum, pharmacokinetics and clinical efficacy

Hemi-synthetic derivatives of glycopeptides have demonstrated bactericidal activity towards Gram-positive bacteria, including vancomycin-resistant strains (oritavancin and telavancin), and a prolonged half-life, allowing for once-daily (oritavancin and telavancin) or once-weekly (dalbavancin) administration. These compounds have proved effective for the treatment of infections caused by multidrug-resistant Gram-positive bacteria, including complicated skin and skin structure infections (oritavancin, telavancin and dalbavancin), bacteremia (oritavancin and dalbavancin) and nosocomial pneumonia. This review compares the antibacterial activity and clinical activity of three glycopeptides, oritavancin, telavancin and dalbavancin, and the natural lipoglycopeptide, ramoplanin, which, being unstable in the bloodstream, is administered orally to treat Clostridium difficile colitis and for digestive tract decontamination. All of these compounds, with the exception of oritavancin, have received Fast Track designation from the FDA because of their clinical efficacy.     

新糖肽类抗生素达巴万星

达巴万星（dalbavancin）是一种新型糖肽类抗生素,其作用机制与万古霉素和替考拉宁相同,抑制G＋菌细胞壁的生物合成.体内、外试验表明,达巴万星对于G＋菌包括耐甲氧西林金葡球菌（MRSA）、甲氧西林敏感金葡球菌（MSSA）、凝固酶阴性葡萄球菌（CoNS）、链球菌等具有抗菌活性.对耐G＋病原菌包括耐青霉素和头孢曲松肺炎链球菌、替考拉宁不敏感CoNS、非vanA型肠球菌具有活性;对G＋厌氧菌也具有活性.达巴万星具独特的药动学性质,可每周间隔用药.目前,达巴万星在治疗导管相关的血源性感染以及皮肤和软组织感染已取得了良好的效果.     

Telavancin for the treatment of serious gram-positive infections,including hospital acquired pneumonia

Introduction: Hospital-acquired pneumonia is a common infection, associated with substantial mortality. Despite the increasing prevalence of nosocomial pneumonia caused by methicillin-resistant Staphylococcus aureus (MRSA), approved treatment options for this pathogen are limited.

Areas covered: This article reviews the pharmacokinetics, dosing, preclinical studies and clinical efficacy, and safety of telavancin, with a particular focus on results from trials in nosocomial pneumonia. PubMed and Congress websites were searched for relevant articles published between 2003 and 2010.

Expert opinion: Telavancin is a lipoglycopeptide antibiotic with rapid, bactericidal activity against MRSA, and may provide another option for the treatment of nosocomial pneumonia, owing to Gram-positive pathogens.     

Tigecycline for the treatment of infections due to resistant Gram-positive organisms

Tigecycline is a novel compound in the antimicrobial class known as the glycylcyclines. In vitro studies have shown it to have activity against the vast majority of Gram-positive pathogens, including multi-drug resistant Staphylococcus aureus and vancomycin-resistant enterococci. Tigecycline has also shown excellent in vitro activity against a broad range of Gram-negative enteric organisms including strains resistant to other antimicrobials as well as anaerobes. Tigecycline is not affected by the ribosomal protection and efflux mechanisms transmitted by the known tetracycline resistance genes. Tigecycline represents an exciting new class of glycylcycline antimicrobial agents for the treatment of multi-drug resistant Gram-positive bacteria. Although its broad spectrum of activity, which also includes Gram-negative enterics, makes it a candidate for empiric therapy for intra-abdominal infections, its spectrum against multi-drug resistant Gram-positive organisms makes it a very attractive choice for empiric treatment of Gram-positive infections in patients at risk for resistant strains. The two pivotal Phase II clinical trials involving complicated skin and soft tissue infections and intra-abdominal infections have shown the drug to be safe and effective.     

Linezolid - a review of the first oxazolidinone

Linezolid is the first of a truly new class of antibiotics, the oxazolidinones. It acts as an inhibitor of bacterial protein synthesis by blocking the formation of the 70S ribosomal initiation complex. Its activity is bacteriostatic against some species (e.g., enterococci) and bactericidal against others (e.g., pneumococci). The antibacterial spectrum of linezolid includes Gram-positive pathogens and some Gram-negative anaerobic species but not Gram-negative aerobes. Importantly, multi-drug resistant organisms such as methicillin-resistant staphylococci, staphylococci with reduced susceptibility to vancomycin, penicillin- and macrolide-resistant pneumococci and vancomycin-resistant enterococci are fully susceptible to linezolid. Linezolid has almost 100% bioavailability and the area under the plasma concentration curve is identical after oral and iv. administration. This enables initial oral administration of linezolid in those patients who can absorb the drug normally and also an early step-down therapy from iv. to oral. Controlled, randomised clinical studies have documented efficacy and safety of linezolid in hospital- and community-acquired pneumonia, uncomplicated and complicated skin and soft tissue infections and infections caused by vancomycin-resistant enterococci. The safety and tolerability of linezolid are advantageous. Linezolid is a weak and reversible monoamine oxidase (MAO) inhibitor and although no increased frequency of adrenergic or serotonergic adverse events has been reported, it is recommended that linezolid is used with caution in patients treated with other MAO inhibitors.     

Linezolid--a review of the first oxazolidinone

Linezolid is the first of a truly new class of antibiotics, the oxazolidinones. It acts as an inhibitor of bacterial protein synthesis by blocking the formation of the 70S ribosomal initiation complex. Its activity is bacteriostatic against some species (e.g., enterococci) and bactericidal against others (e.g., pneumococci). The antibacterial spectrum of linezolid includes Gram-positive pathogens and some Gram-negative anaerobic species but not Gram-negative aerobes. Importantly, multi-drug resistant organisms such as methicillin-resistant staphylococci, staphylococci with reduced susceptibility to vancomycin, penicillin- and macrolide-resistant pneumococci and vancomycin-resistant enterococci are fully susceptible to linezolid. Linezolid has almost 100% bioavailability and the area under the plasma concentration curve is identical after oral and iv. administration. This enables initial oral administration of linezolid in those patients who can absorb the drug normally and also an early step-down therapy from iv. to oral. Controlled, randomised clinical studies have documented efficacy and safety of linezolid in hospital- and community-acquired pneumonia, uncomplicated and complicated skin and soft tissue infections and infections caused by vancomycin-resistant enterococci. The safety and tolerability of linezolid are advantageous. Linezolid is a weak and reversible monoamine oxidase (MAO) inhibitor and although no increased frequency of adrenergic or serotonergic adverse events has been reported, it is recommended that linezolid is used with caution in patients treated with other MAO inhibitors.     

The importance of tissue penetration in achieving successful antimicrobial treatment of nosocomial pneumonia and complicated skin and soft-tissue infections caused by methicillin-resistant Staphylococcus aureus: vancomycin and linezolid

Abstract

Background:

The rising prevalence of nosocomial methicillin-resistant Staphylococcus aureus (MRSA) and the recent emergence of community-associated MRSA are major clinical, public health, and economic challenges. MRSA is a leading cause of nosocomial pneumonia and complicated skin and soft-tissue infections (cSSTI). Vancomycin and linezolid are two commonly used antimicrobial agents with activity against Gram-positive pathogens, particularly MRSA, that are used to treat both nosocomial pneumonia and cSSTI. Recently, the therapeutic efficacy of vancomycin in the treatment of hospitalized patients with MRSA infections has been questioned due to the emergence of MRSA strains with reduced susceptibility to vancomycin together with concerns related to inadequate dosing and poor tissue penetration of the drug.