Eficacia y seguridad de daptomicina en dosis elevadas (≥ 8mg/kg/día)

Population Pharmacokinetic/Pharmacodynamic Modelling of Daptomycin for Schedule Optimization in Patients with Renal Impairment

The aims of this study are (i) to develop a population pharmacokinetic/pharmacodynamic model of daptomycin in patients with normal and impaired renal function, and (ii) to establish the optimal dose recommendation of daptomycin in clinical practice. Several structural PK models including linear and non-linear binding kinetics were evaluated. Monte Carlo simulations were conducted with a fixed combination of creatinine clearance (30-90 mL/min/1.73 m2) and body weight (50-100 kg). The final dataset included 46 patients and 157 daptomycin observations. A two-compartment model with first-order peripheral distribution and elimination kinetics assuming non-linear protein-binding kinetics was selected. The bactericidal effect for Gram+ strains with MIC ≤ 0.5 mg/L could be achieved with 5-12 mg/kg daily daptomycin based on body weight and renal function. The administration of 10-17 mg/kg q48 h daptomycin allows to achieve bactericidal effect for Gram+ strains with MIC ≤ 1 mg/L. Four PK samples were selected as the optimal sampling strategy for an accurate AUC estimation. A quantitative framework has served to characterize the non-linear binding kinetics of daptomycin in patients with normal and impaired renal function. The impact of different dosing regimens on the efficacy and safety outcomes of daptomycin treatment based on the unbound exposure of daptomycin and individual patient characteristics has been evaluated.

Evaluation of Effectiveness and Safety of High-Dose Daptomycin: Results from Patients Included in the European Cubicin(®) Outcomes Registry and Experience

INTRODUCTION

Daptomycin, a rapid concentration-dependent bactericidal antibiotic, is approved at a dose of 4 mg/kg/day for the treatment of complicated skin and soft tissue infections (cSSTI) and at a dose of 6 mg/kg/day for the treatment of Staphylococcus aureus right-sided infective endocarditis (RIE) and bacteremia associated with cSSTI and RIE. Studies have reported the successful use of high-dose daptomycin (>6 mg/kg/day) in patients with difficult-to-treat infections. The present analysis evaluated the effectiveness and safety of high doses (>6 mg/kg/day) of daptomycin for the treatment of different Gram-positive infections.

METHODS

European Cubicin(®) Outcomes Registry and Experience (EU-CORE) is a non-interventional, multicenter, retrospective, patient registry designed to collect real-world data from patients treated with daptomycin between 2006 and 2012. Clinical outcomes were assessed at the end of daptomycin treatment for three dose groups: ≤6, >6 to <8, and ≥8 mg/kg/day. Safety was assessed for up to 30 days post-daptomycin treatment.

RESULTS

Of the 6075 patients enrolled in EU-CORE, 4892 patients received daptomycin doses ≤6 mg/kg/day, while 1097 patients received high doses (>6 mg/kg/day). The primary infections with the largest proportion of patients treated with a high dose (>6 mg/kg/day) were osteomyelitis (37.1%), foreign body/prosthetic infection (31.6%), and endocarditis (27.6%). S. aureus was identified in 42.9% of patients with positive cultures treated with either ≤6 or >6 mg/kg/day. The overall clinical success rate was 82.0% (899/1097) with high doses (>6 mg/kg/day) and 80.3% (3928/4890) with doses ≤6 mg/kg/day. Numerically higher clinical success rate was observed for endocarditis and foreign body/prosthetic infection, as well as for coagulase-negative staphylococcal and enterococcal infections, with high-dose daptomycin treatment. There were no new or unexpected safety findings at doses >6 mg/kg/day.

CONCLUSION

These results suggested that daptomycin at doses >6 mg/kg/day was effective and well tolerated. High-dose daptomycin is a potential therapeutic option in patients with difficult-to-treat Gram-positive infections.

FUNDING

This study was funded by Novartis Pharma AG.

Towards a definition of daptomycin optimal dose: Lessons learned from experimental and clinical data

Daptomycin exhibits excellent antibacterial activity against a wide range of Gram-positive bacteria. The on-label standard daily doses for daptomycin are 4 mg/kg for skin infections and 6 mg/kg for bacteraemia or right-sided endocarditis. Daptomycin bactericidal activity is predominantly concentration-dependent and by considering the values of pharmacokinetic targets established by several authors as well as the peak and trough concentrations of daptomycin obtained at various daily dosages, it appears that these targets can easily be reached with a dose of 6 mg/kg but only for a minimum inhibitory concentration (MIC) at 0.1 mg/L, and that for increasing MICs (e.g. 0.5 mg/L or 1 mg/L) these targets may only be attained with higher dosages (i.e. ≥10 mg/kg). High-dose (HD) daptomycin therapy has also been proven to be effective for reducing the risk of selection of daptomycin-resistant strains. Given the concentration-dependent bactericidal activity of daptomycin, the absence of a dose-toxicity relationship and the need to prevent the selection of resistant strains, we propose to consider for staphylococcal (i) skin and soft-tissue infections, daily doses of daptomycin of 6 mg/kg (new standard dose) and (ii) endocarditis or bacteraemia including those associated with intravascular catheter and implant-related infections, ≥10 mg/kg (HD) when the MIC is unknown or >0.25 mg/L, and 6-10 mg/kg (intermediate doses) when the MIC is ≤0.25 mg/L. For severe and deep-seated enterococcal infections, we propose high (≥10 mg/kg) daily doses of daptomycin in combination with another active agent, especially a β-lactam.

Clinical experience with the use of daptomycin in a tertiary care teaching hospital in Barcelona, Spain

AIM

We reviewed the clinical use of daptomycin in daily practice.

MATERIALS & METHODS

Efficacy and safety were assessed in 175 consecutive patients given daptomycin for at least 72 h.

RESULTS

Daptomycin was given as rescue treatment in 50.9% of cases. Bloodstream infection (34.8%) and skin/soft-tissue infection (19.4%) were the most frequent. In 62.3% of patients, the dose of ≤ 6 mg/kg/day was administered. Staphylococcus spp. were isolated in 52.6% of cases (MRSA in 9.5%, CoNS in 34.3%) and Enterococcus spp. in 8.7%. Clinical success was 75% and microbiological eradication 48.6%. Two patients discontinued daptomycin due to hemolytic anemia of unlikely and possible relationship with daptomycin, respectively.

CONCLUSION

Daptomycin was effective and well tolerated in patients with severe Gram-positive infections.

Tolerability of High Doses of Daptomycin in the Treatment of Prosthetic Vascular Graft Infection: A Retrospective Study

INTRODUCTION

In treatment of prosthetic vascular graft infection (PVGI), appropriate antimicrobial treatment is crucial for controlling the septic process and preventing re-infection of the new graft. Glycopeptides are the mainstay of treatment for device-related infections by methicillin-resistant Staphylococcus aureus strains, but with some limitations, especially concerning vancomycin-intermediate and glycopeptide-intermediate S. aureus. We report our experience using a high dose of daptomycin (DAP) for treatment of PVGI.

METHODS

We reviewed medical reports of 26 patients treated with high doses of DAP (>8 mg/kg) and beta-lactams/aminosides for PVGI, defined as positive bacterial culture of intraoperative specimens or blood samples and/or clinical, biological, and radiological signs of infection. Clinical success was defined by resolution of all clinical signs at the end of follow-up, without the need for additional antibiotic therapy, and/or negative culture in case of new surgery.

RESULTS

Cultures of intraoperative samples were positive in 21 patients (80.8%). Blood and intraoperative cultures were concomitantly positive in 10 patients. The main microorganism identified in microbiological samples was S. aureus (n = 18). Surgery was performed in 23 patients (88.4%). The mean duration of the DAP regimen was 12.3 ± 11.9 days. DAP was discontinued in 26 patients [need to switch to microbiological results (n = 19), bacterial pneumonia (n = 2), and increased creatine phosphokinase levels (n = 4)]. One patient had myalgia, while 9 received concomitant statins.

CONCLUSION

High-dose DAP therapy shows a satisfactory toxicity profile even in severely ill patients with multiple comorbidities, and may favorably compete with vancomycin, especially concerning the risk of induced nephrotoxicity.

Defining daptomycin resistance prevention exposures in vancomycin-resistant Enterococcus faecium and E. faecalis

Daptomycin is used off-label for enterococcal infections; however, dosing targets for resistance prevention remain undefined. Doses of 4 to 6 mg/kg of body weight/day approved for staphylococci are likely inadequate against enterococci due to reduced susceptibility. We modeled daptomycin regimens in vitro to determine the minimum exposure to prevent daptomycin resistance (Dapr) in enterococci. Daptomycin simulations of 4 to 12 mg/kg/day (maximum concentration of drug in serum [Cmax] of 57.8, 93.9, 123.3, 141.1, and 183.7 mg/liter; half-life [t1/2] of 8 h) were tested against one Enterococcus faecium strain (S447) and one Enterococcus faecalis strain (S613) in a simulated endocardial vegetation pharmacokinetic/pharmacodynamic model over 14 days. Samples were plated on media containing 3× the MIC of daptomycin to detect Dapr. Mutations in genes encoding proteins associated with cell envelope homeostasis (yycFG and liaFSR) and phospholipid metabolism (cardiolipin synthase [cls] and cyclopropane fatty acid synthetase [cfa]) were investigated in Dapr derivatives. Dapr derivatives were assessed for changes in susceptibility, surface charge, membrane depolarization, cell wall thickness (CWT), and growth rate. Strains S447 and S613 developed Dapr after simulations of 4 to 8 mg/kg/day but not 10 to 12 mg/kg/day. MICs for Dapr strains ranged from 8 to 256 mg/liter. Some S613 derivatives developed mutations in liaF or cls. S447 derivatives lacked mutations in these genes. Dapr derivatives from both strains exhibited lowered growth rates, up to a 72% reduction in daptomycin-induced depolarization and up to 6-nm increases in CWT (P<0.01). Peak/MIC and AUC0-24/MIC ratios (AUC0-24 is the area under the concentration-time curve from 0 to 24 h) associated with Dapr prevention were 72.1 and 780 for S447 and 144 and 1561 for S613, respectively. Daptomycin doses of 10 mg/kg/day may be required to prevent Dapr in serious enterococcal infections.

Current pharmacotherapy options for osteomyelitis: convergences, divergences and lessons to be drawn

INTRODUCTION

Antibiotic therapy of osteomyelitis is complex and requires a multidisciplinary approach including surgeons and infectious diseases specialists. However, it suffers from a lack of high-quality clinical studies indicating the superiority of one type of therapy over another. Knowing the antibiotics and their main characteristics is important to guide the choice of treatment for patients with osteomyelitis.

AREAS COVERED

The aim of the present article is to review the systemic curative antibiotic therapy of osteomyelitis in adults with a focus on new agents. Diabetic foot osteomyelitis will be briefly discussed separately. A literature search of the PubMed database using the term 'osteomyelitis' alone and in combination with 'hematogenous', 'vertebral', 'biofilm', 'diabetic foot', 'trauma', 'antibiotic' 'daptomycin', 'telavancin', 'tigecycline', 'linezolid', 'ertapenem', 'ceftobiprole' and 'ceftaroline' was carried out.

EXPERT OPINION

Antibiotic treatment of acute and chronic osteomyelitis should be considered as two distinct entities with regard to the choice of the most appropriate antibiotics and the need for surgery. Among the most recently available antibiotics, ertapenem and daptomycin are promising agents for the treatment of osteomyelitis due to resistant bacteria.

Brazilian experience in EU-CORE: daptomycin registry and treatment of serious Gram-positive infections

Objectives

To collect data about non-controlled prescribing use of daptomycin and its impact among Brazilian patients with serious Gram positive bacterial infection, as well as the efficacy and safety outcomes.

Materials and methods

This is a multi-center, retrospective, non-interventional registry (August 01, 2009 to June 30, 2011) to collect data on 120 patients (44 patients in the first year and 76 patients in the second year) who had received at least one dose of commercial daptomycin in Brazil for the treatment of serious Gram-positive bacterial infection.

Results

Right-sided endocarditis (15.8%), complicated skin and soft tissue infections (cSSTI)-wound (15.0%) and bacteremia-catheter-related (14.2%) were the most frequent primary infections; lung (21.7%) was the most common site for infection. Daptomycin was used empirically in 76 (63.3%) patients, and methicillin-resistant Staphylococcus aureus (MRSA) was the most common suspected pathogen (86.1%). 82.5% of the cultures were obtained prior to or shortly after initiation of daptomycin therapy. Staphylococcus spp. – coagulase negative, MRSA, and methicillin-susceptible S. aureus were the most frequently identified pathogens (23.8%, 23.8% and 12.5%, respectively). The most common daptomycin dose administered for bacteremia and cSSTI was 6 mg/kg (30.6%) and 4 mg/kg (51.7%), respectively. The median duration of inpatient daptomycin therapy was 14 days. Most patients (57.1%) did not receive daptomycin while in intensive care unit. Carbapenem (22.5%) was the most commonly used antibiotic concomitantly. The patients showed clinical improvement after two days (median) following the start of daptomycin therapy. The clinical success rate was 80.8% and the overall rate of treatment failure was 10.8%. The main reasons for daptomycin discontinuation were successful end of therapy (75.8%), switched therapy (11.7%), and treatment failure (4.2%). Daptomycin demonstrated a favorable safety and tolerability profile regardless of treatment duration.

Conclusions

Daptomycin had a relevant role in the treatment of Gram-positive infections in the clinical practice setting in Brazil.