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Background: Daptomycin stands as a key IV antibiotic in treating MRSA infections. However, patients facing challenges with difficult venous access require alternative administration routes. This study aimed to evaluate the pharmacokinetic (PK) profile and safety of subcutaneous (SC) daptomycin., Patients and Methods: In a two-period, two-treatment, single-blind crossover Phase I trial (ClinicalTrials.gov NCT04434300), participants with no medical history received daptomycin (10 mg/kg) both IV and SC in a random order, with a minimum 2 week washout period together with matched placebo (NaCl 0.9%). Blood samples collected over 24 h facilitated PK comparison. Monte Carlo simulations assessed the PTA for various dosing regimens. Adverse events were graded according to Common Terminology Criteria for Adverse Events(CTCAE) v5.0., Results: Twelve participants (aged 30.9 ± 24.4 years; 9 male,75%) were included. SC daptomycin exhibited delayed (median Tmax 0.5 h for IV versus 4 h for SC) and lower peak concentration than IV (Cmax = 132.2 ± 16.0 μg/mL for IV versus 57.3 ± 8.6 μg/mL for SC; P < 0.001). SC AUC0-24 (937.3 ± 102.5 μg·h/mL) was significantly lower (P = 0.005) than IV AUC0-24 (1056.3 ± 123.5 μg·h/mL) but was deemed bioequivalent. PTA demonstrated target AUC0-24 attainment for 100% of simulated individuals, for both 8 and 10 mg/kg/24 h SC regimens. Adverse events (AEs) related to SC daptomycin were more frequent than for SC placebo (25 versus 13, P = 0.016). No serious AEs were reported., Conclusions: Single-dose SC daptomycin infusion proved to be safe, exhibiting a bioequivalent AUC0-24 compared with the IV route. The SC route emerges as a potential and effective alternative when IV administration is not possible., (© The Author(s) 2024. Published by Oxford University Press on behalf of British Society for Antimicrobial Chemotherapy. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

Purpose: Cardiac implantable electronic device (CIED) infections are increasingly common. Gram-positive bacteria such as coagulase negative staphylococci and Staphylococcus aureus are the most commonly involved pathogens. The aim of this study was to describe the characteristics and outcome of patients with CIED infections who underwent device removal and were empirically treated with high dose (8-12 mg/kg daily) daptomycin (DAP) in combination with ceftriaxone (CRO)., Methods: Retrospective, single center study including patients admitted at IRCCS San Raffaele Hospital (Milan, Italy), from June 2011 to June 2021, who underwent device removal for CIED infection and were empirically treated with DAP/CRO., Findings: Overall, 147 patients were included in this study. Median duration of therapy was 16 days (IQR 14-26). Empirical treatment with DAP/CRO was confirmed as definitive treatment in 140 patients (95.2%). In 7 (4.8%) patients DAP/CRO were discontinued according to the definite microbiological isolates: Corynebacterium spp. (4), Pseudomonas aeruginosa (2), Enterobacter cloacae (1). Ten patients (6.8%) underwent treatment simplification to narrow-spectrum antibiotics. One patient (0.6%) interrupted DAP-CRO due to pancytopenia. 6-month follow-up was available for 123/147 patients (83.7%): 9 patients recurred with a CIED infection (7.3%), and 9 died (7.3%)., Implications: In our 10-year experience, high-dose DAP in combination with CRO represented a good option for empirical therapy of CIED infections. DAP-CRO combination was safe and effective, showing no significant drug-related adverse events and low rates of 6-month recurrence and mortality., Competing Interests: Declaration of competing interest The authors have no relevant financial or non-financial interests to disclose., (Copyright © 2024 Elsevier Inc. All rights reserved.)

This study investigated the patterns of hematological adverse events related to daptomycin (DAP), tigecycline (TIG), vancomycin (VAN) and linezolid (LIN) in the FDA Adverse Event Reporting System (FAERS). Adverse event associations were analyzed through calculating reporting odds ratio (ROR), proportional reporting ratio (PRR), multiple gamma Poisson shrinkage (MGPS), and Bayesian confidence propagation neural network (BCPNN). A comprehensive descriptive analysis was also conducted considering factors such as age, gender, daily dose, cumulative dose, and time to onset. The leading hematologic adverse events were eosinophilia for daptomycin, coagulation abnormalities and thrombocytopenia for tigecycline, thrombocytopenia, neutropenia, and anemia for linezolid, and thrombocytopenia, eosinophilia, and neutropenia for vancomycin. Most of the affected patients were over 55 years old. Daily doses for the tigecycline and daptomycin groups exceeded the standard daily dose. The times to onset were 14.00 days for daptomycin (interquartile range [IQR], 4.00-21.00), 6.00 days for tigecycline (IQR, 2.00-9.00), 10.00 days for linezolid (IQR, 4.00-16.5), and 10.00 days for vancomycin (IQR,5.00-20.00). It is essential to intensify early monitoring and identification of these adverse events, especially in the context of off-label dosages and for elderly patients and individuals taking medication for over one week.

Precision daptomycin dosing faces clinical implementation barriers despite known exposure-safety concerns with the use of twice the regulatory-approved doses. We propose achieving a single 7-11-hour post-dose plasma target concentration of 30 mg/L to 43 mg/L to be a practical starting point to facilitate precision daptomycin dosing., Competing Interests: Potential conflicts of interest . The authors: No reported conflicts of interest. All authors have submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Conflicts that the editors consider relevant to the content of the manuscript have been disclosed., (© The Author(s) 2024. Published by Oxford University Press on behalf of Infectious Diseases Society of America. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

Background and Objective: The dosage of daptomycin is usually based on body weight. However, it has been shown that this approach yields too high an exposure in obese patients. Pharmacokinetic and pharmacodynamic indexes (PK/PD) have been proposed for daptomycin's antibacterial effect (AUC/CMI >666) and toxicity (C0 > 24.3 mg/L). We previously developed machine learning (ML) algorithms to predict starting doses based on Monte Carlo simulations. We propose a new way to perform probability of target attainment based on an ML algorithm to predict the daptomycin starting dose., Methods: The Dvorchik model of daptomycin was implemented in the mrgsolve R package and 4950 pharmacokinetic profiles were simulated with doses ranging from 4 to 12 mg/kg. We trained and benchmarked four machine learning algorithms and selected the best to iteratively search for the optimal dose of daptomycin maximizing the event (AUC/CMI > 666 and C0 < 24.3 mg/L). The ML algorithm was evaluated in simulations and an external database of real patients in comparison with population pharmacokinetics., Results: The performance of the Xgboost algorithms developed to predict the event (ROC AUC) in the training and test set were 0.762 and 0.761, respectively. The most important prediction variables were dose, creatinine clearance, body weight and sex. In the external database of real patients, the starting dose administered based on the ML algorithm significantly improved the target attainment by 7.9% (p-value = 0.02929) in comparison with the dose administered based on body weight., Conclusion: The developed algorithm improved the target attainment for daptomycin in comparison with weight-based dosing. We built a Shiny app to calculate the optimal starting dose., (© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Background: Daptomycin is a high-use intravenous antimicrobial agent affording the convenience of once-daily dosing. Prior studies suggest an opportunity to use a more operationally convenient fixed rather than weight-based dosing but this approach has not been studied prospectively., Methods: This study quantified the probability of toxicity and efficacy end points by prospectively testing a fixed dose regimen of daptomycin (750 mg) in obese and non-obese adults. At least, three daptomycin concentrations were measured at steady-state for each patient. A population pharmacokinetic model was constructed to evaluate concentration-time profiles and investigate covariates of daptomycin clearance. Simulations were performed to evaluate the probability of achieving efficacy (24-h area under the curve (AUC 0-24 ) ≥ 666 mg∙h/L) and toxicity (minimum concentration (C min ) ≥24.3 mg/L) targets for fixed (500-1000 mg) and weight-based (6-12 mg/kg) daptomycin doses., Results: Thirty-one patients (16 females, 15 males) with median (interquartile range (IQR)) age of 50 (30, 62) years and weight of 74 (54, 156) kg were included in the final analysis. Fixed dose daptomycin (750 mg) resulted in similar exposure across weights with a median (IQR) AUC 0-24 of 819 (499, 1501) mg∙h/L and 749 (606, 1265) mg∙h/L in patients weighing ≤74 kg and >74 kg, respectively. Overall, male sex and increased kidney function necessitate higher fixed and weight-based doses to achieve efficacy. Creatine phosphokinase elevation was observed in two patients (6.5%) and predicted to be lower with fixed versus weight-based regimens., Conclusions: Fixed daptomycin dosing adjusted for sex and kidney function is expected to improve the efficacy-to-toxicity ratio, transitions of care, and costs compared to weight-based doses. However, no empiric dosing approach is predicted to achieve ≥90% efficacy while minimizing the risk of toxicity, so therapeutic drug monitoring should be considered on a patient-specific basis., (© 2024 Pharmacotherapy Publications, Inc.)

Background: We report the final results of the clinical usage of ceftobiprole in patients in Canada from data in the national CLEAR (Canadian Le adership on Antimicrobial Real-Life Usage) registry., Research Design and Methods: The authors review the final data using the national ethics approved CLEAR study. Thereafter, the literature is surveyed regarding the usage of ceftobiprole to treat patients with infectious diseases via PubMed (up to March 2024)., Results: In Canada, ceftobiprole is primarily used as directed therapy to treat a variety of severe infections caused by MRSA. It is primarily used in patients failing previous antimicrobials, is frequently added to daptomycin and/or vancomycin with high microbiological and clinical cure rates, along with an excellent safety profile. Several reports attest to the microbiological/clinical efficacy and safety of ceftobiprole. Ceftobiprole is also reported to be used empirically in select patients with community-acquired bacterial pneumonia (CABP), as well as hospital-acquired bacterial pneumonia (HABP)., Conclusions: In Canada, ceftobiprole is used mostly as directed therapy to treat a variety of severe infections caused by MRSA, in patients failing previous antimicrobials. It is frequently added to, and thus used in combination with daptomycin and/or vancomycin with high microbiological/clinical cure rates, and an excellent safety profile.

Background: Daptomycin is widely used in critically ill patients for Gram-positive bacterial infections. Extracorporeal membrane oxygenation (ECMO) is increasingly used in this population and can potentially alter the pharmacokinetic (PK) behaviour of antibiotics. However, the effect of ECMO has not been evaluated in daptomycin. Our study aims to explore the effect of ECMO on daptomycin in critically ill patients through population pharmacokinetic (PopPK) analysis and to determine optimal dosage regimens based on both efficacy and safety considerations., Methods: A prospective, open-label PK study was carried out in critically ill patients with or without ECMO. The total concentration of daptomycin was determined by UPLC-MS/MS. NONMEM was used for PopPK analysis and Monte Carlo simulations., Results: Two hundred and ninety-three plasma samples were collected from 36 critically ill patients, 24 of whom received ECMO support. A two-compartment model with first-order elimination can best describe the PK of daptomycin. Creatinine clearance (CLCR) significantly affects the clearance of daptomycin while ECMO has no significant effect on the PK parameters. Monte Carlo simulations showed that, when the MICs for bacteria are  ≥1 mg/L, the currently recommended dosage regimen is insufficient for critically ill patients with CLCR > 30 mL/min. Our simulations suggest 10 mg/kg for patients with CLCR between 30 and 90 mL/min, and 12 mg/kg for patients with CLCR higher than 90 mL/min., Conclusions: This is the first PopPK model of daptomycin in ECMO patients. Optimal dosage regimens considering efficacy, safety, and pathogens were provided for critical patients based on pharmacokinetic-pharmacodynamic analysis., (© The Author(s) 2024. Published by Oxford University Press on behalf of British Society for Antimicrobial Chemotherapy. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

Staphylococcus aureus bacteremia presents clinical complexities, with prolonged duration associated with unfavorable outcomes. This research delves into unconventional treatments, such as combinations involving daptomycin, oxacillin, ceftaroline, and fosfomycin, with the aim of swiftly sterilizing bloodstream infection to reduce complications. Our examination of 30 MSSA bacteremia patients with infective endocarditis uncovers differing results between single-agent therapies (oxacillin or daptomycin) and combined treatment plans. Microbiologic clearance at the 72 hour mark demonstrates greater efficacy within the combination cohort (bacteremia persistence 29%) versus monotherapy (bacteremia persistence 78%). This limited case series suggests the potential superiority of combination therapy, prompting further investigations.

Purpose: Few studies describe the efficacy of antibiotic lock therapy (ALT) in long-term catheter-related bloodstream (CRBSI) infections. We applied local protocols combining Daptomycin (DPT) and Taurolidine ALT, associated with systemic antibiotic treatment (SAT), for conservative management of coagulase-negative Staphylococci (CoNS) CRBSI., Methods: Patients admitted for CoNS-associated CRBSI and treated with DPT and Taurolidine as ALT were retrospectively analyzed. Success was defined as catheter retention 30 days after ending treatment. Catheter removal within 30 days was considered as failure., Results: From April 2018 to September 2021, 22 subjects with CoNS-associated-CRBSI were included (95% with cancer, mean age 64 years, 59% male). Staphylococcus epidermidis was isolated in 82% of cases. Mean duration of DPT was 3.9 and 3 days as ALT and SAT, respectively. SAT also included Rifampin for 3 days. Taurolidine ALT was started on day 4 and was combined with oral SAT, that is, either Linezolid or Tedizolid. Mean duration of Taurolidine was 10.5 days, while total antibiotic treatment lasted 13.5 days. Clinical success and failure rates were 95% and 5%, respectively., Discussion: Short course DPT as ALT, combined with SAT and Taurolidine ALT, allowed high rates of conservative management of catheters in case of CoNS-associated-CRBSI., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Daptomycin is an antibiotic with Gram-positive activity, including methicillin-resistant Staphylococcus aureus, for which optimal pediatric dosing is unknown. This study aimed to evaluate daptomycin exposures achieved with package label dosing and to identify dosing regimens necessary to enhance efficacy and minimize toxicity in children with S. aureus bacteremia. Monte Carlo simulations were performed to determine probability of target attainment (PTA) for six pediatric age cohorts. Area under the curve to minimum inhibitory concentration ratio (AUC 0-24 :MIC) ≥666 was used to determine the PTA for efficacy (PTA E ). Minimum concentration (C min ) ≥24.3 mg/L determined the PTA for toxicity (PTA T ). Acceptable dosing regimens were those which achieved the combined target of ≥90% PTA E and ≤5% PTA T . Package label dosing of daptomycin yielded insufficient efficacy with only 26.3% PTA E in children 13-24 months, 39.5% PTA E in children 2-6 years, 30.1% PTA E in children 7-11 years, and 50.1% PTA E in adolescents ≥12 years. To achieve the combined efficacy and safety target, doses of 18-24 mg/kg in children 3-12 months, 20-24 mg/kg in children 13-24 months, 19-24 mg/kg in children 2-6 years, 17-19 mg/kg in children 7-11 years, and 10-14 mg/kg in adolescents ≥12 years are necessary. Package label dosing resulted in suboptimal exposure for the majority of pediatric patients in all age groups evaluated. If targeting validated efficacy and safety endpoints, daily daptomycin doses of at least 20 mg/kg in children ≤6 years, 17 mg/kg in children 7-11 years, and 10 mg/kg in adolescents ≥12 years are necessary. Clinical studies evaluating these higher doses are needed., (© 2024, The American College of Clinical Pharmacology.)

Background: Ceftobiprole is a cephalosporin that may be effective for treating complicated Staphylococcus aureus bacteremia, including methicillin-resistant S. aureus ., Methods: In this phase 3, double-blind, double-dummy, noninferiority trial, adults with complicated S. aureus bacteremia were randomly assigned in a 1:1 ratio to receive ceftobiprole at a dose of 500 mg intravenously every 6 hours for 8 days and every 8 hours thereafter, or daptomycin at a dose of 6 to 10 mg per kilogram of body weight intravenously every 24 hours plus optional aztreonam (at the discretion of the trial-site investigators). The primary outcome, overall treatment success 70 days after randomization (defined as survival, bacteremia clearance, symptom improvement, no new S. aureus bacteremia-related complications, and no receipt of other potentially effective antibiotics), with a noninferiority margin of 15%, was adjudicated by a data review committee whose members were unaware of the trial-group assignments. Safety was also assessed., Results: Of 390 patients who underwent randomization, 387 (189 in the ceftobiprole group and 198 in the daptomycin group) had confirmed S. aureus bacteremia and received ceftobiprole or daptomycin (modified intention-to-treat population). A total of 132 of 189 patients (69.8%) in the ceftobiprole group and 136 of 198 patients (68.7%) in the daptomycin group had overall treatment success (adjusted difference, 2.0 percentage points; 95% confidence interval [CI], -7.1 to 11.1). Findings appeared to be consistent between the ceftobiprole and daptomycin groups in key subgroups and with respect to secondary outcomes, including mortality (9.0% and 9.1%, respectively; 95% CI, -6.2 to 5.2) and the percentage of patients with microbiologic eradication (82.0% and 77.3%; 95% CI, -2.9 to 13.0). Adverse events were reported in 121 of 191 patients (63.4%) who received ceftobiprole and 117 of 198 patients (59.1%) who received daptomycin; serious adverse events were reported in 36 patients (18.8%) and 45 patients (22.7%), respectively. Gastrointestinal adverse events (primarily mild nausea) were more frequent with ceftobiprole., Conclusions: Ceftobiprole was noninferior to daptomycin with respect to overall treatment success in patients with complicated S. aureus bacteremia. (Funded by Basilea Pharmaceutica International and the U.S. Department of Health and Human Services; ERADICATE ClinicalTrials.gov number, NCT03138733.)., (Copyright © 2023 Massachusetts Medical Society.)

Introduction: The pharmacokinetics (PK) of daptomycin has not been previously characterized in Japanese pediatric patients with complicated skin and soft tissue infections (cSSTI) or bacteremia. An aim of the study includes evaluation of PK of daptomycin in Japanese pediatric patients and an appropriateness of the age-specific, weight-based dosing regimens in Japanese pediatric patients based on PK comparison with Japanese adult patients., Methods: The phase 2 trial enrolled Japanese pediatric patients (age 1-17 years) with cSSTI (n = 14) or bacteremia (n = 4) caused by gram-positive cocci in order to evaluate safety, efficacy and PK. The Phase 3 trial in Japanese adult patients (SSTI n = 65, septicemia/right-sided infective endocarditis (RIE) n = 7) was referred to for PK comparison between adult and pediatric. Daptomycin concentrations in plasma were analyzed by reverse-phase high-performance liquid chromatography (HPLC). PK parameters were determined using non-compartmental analysis in Japanese pediatric and Japanese adult patients. The exposures in Japanese pediatric patients were graphically compared with those in Japanese adult patients. The relationship between daptomycin exposures and creatine phosphokinase (CPK) elevation was explored visually., Results: Following administration of the age-specific, weight-based dosing regimens, daptomycin exposures were overlapping across age groups in pediatric patients with cSSTI with similar observations based on clearance. The distribution of individual exposure in Japanese pediatric patients was overlapping with that in Japanese adult patients. No apparent relationship between daptomycin exposures and CPK elevation in Japanese pediatric patients was observed., Conclusions: The results suggested that the age-specific, weight-based dosing regimens are considered to be appropriate in Japanese pediatric patients., Competing Interests: Declaration of competing interest Rebecca E Wrishko is employee of Merck & Co., Inc., Rahway, NJ, USA, and all other authors are employees of MSD K.K. Employees may hold stock and/or stock options in the company., (Copyright © 2023 Japanese Society of Chemotherapy, Japanese Association for Infectious Diseases, and Japanese Society for Infection Prevention and Control. Published by Elsevier Ltd. All rights reserved.)

Daptomycin possesses excellent activity against many multidrug-resistant gram positive organisms. However, a side effect of concern with daptomycin is skeletal muscle injury, which is manifested in the form of elevated creatine phosphokinase (CPK). Management of such CPK elevations has traditionally been discontinuation of the offending agent, with many studies showing a resolution of a normal CPK level within 1 week of discontinuation and no long term adverse effects. Nevertheless, the question remains if daptomycin can be successfully restarted in such patients. Here, we present a case of a "daptomycin holiday" in which daptomycin was withheld upon CPK elevation and successfully reintroduced to the patient's regimen again after several days without further elevation of the CPK. The patient had a peak CPK of 2,557 U/L, and had no associated symptoms. A hypothesis for this holiday could be the adaptability of the skeletal muscle myocytes, in which the extra period between doses may allow for additional recovery of the membrane structure to further daptomycin exposure. Giving an asymptomatic patient with elevated CPK level, a short daptomycin holiday to allow for the CPK level to trend downward before resuming daptomycin therapy could be a potential strategy in patients for whom continuing daptomycin is still preferred.

The objective of this study was to evaluate the efficacy of various dosing regimens of vancomycin, teicoplanin, linezolid and daptomycin against methicillin-resistant Staphylococcus aureus (MRSA) in neutropenic patients with cancer. Monte Carlo simulations were conducted using pharmacokinetic parameters and pharmacodynamic data to determine cumulative fraction of response (CFRs) in terms of area under the concentration-time curve/minimum inhibition concentration target. Currently clinical standard dosing regimens of vancomycin, teicoplanin, linezolid and daptomycin were insufficient to provide expected CFRs against MRSA for neutropenic patients with cancer. The high dosing regimens of vancomycin (3500 mg/d), teicoplanin (800 mg/d) and daptomycin (8 mg/kg/d) could provide CFRs of ≥ 80%, showing a higher treatment success. However, the majority of CFRs with linezolid simulated dosing regimens reached < 80% against MRSA. Therefore, a strategy of high dosages of vancomycin, teicoplanin and daptomycin may be needed to attain optimal therapeutic efficacy against MRSA in neutropenic patients with cancer.

Data demonstrating that antibiotics administered intraoperatively in patients with surgical revision for periprosthetic joint infection achieve concentrations exceeding minimal inhibitory concentrations of the identified bacteria at the surgical site when the new implant is inserted are lacking. We prospectively included patients with periprosthetic joint infection operated with one- or two-stage replacement during which cefepime (2g)-daptomycin (10mg/kg) combination was administered intravenously as intraoperative empirical antibiotic treatment. Three biopsies (two bones and one synovial membrane) were taken from each patient just before the insertion of the new implant. Eighteen adults of median age 68 years were included. Knee was involved in 10 patients (55.6%) and surgery consisted in one-/two-stage replacement in 11/7 patients. A tourniquet was used during the intervention in the 10 patients with knee prosthesis. Among 54 tissue samples, cefepime and daptomycin were detected respectively in 35 (64.8%) and 21 (38.9%) cases (P=0.01). A total of 17 bacteria dominated by staphylococci (n=14) were identified in 10 patients; tissue inhibitory quotient calculated in 51 samples was >1 in 22 cases (43.1%) for cefepime and in 16 cases (31.4%) for daptomycin. The proportion of tissue samples with detectable antibiotic was significantly higher in hip versus knee prosthesis (P=0.03). The present study suggests that intraoperative empirical administration of cefepime-daptomycin combination during septic prosthetic joint replacement results in a high proportion of tissue samples in which at least one of the two antibiotics was not detected or at a low concentration despite satisfactory concomitant blood serum concentrations., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Streptococci still represent common etiologic agents of infective endocarditis (IE). Although renal failure is frequently reported as an aminoglycoside-associated adverse event, last international guidelines recommend a beta-lactam/gentamicin combination therapy. We retrospectively evaluated the use of daptomycin-based aminoglycoside-sparing combination therapy for the treatment of streptococcal IE in seven referral hospitals in Italy. Retrospective, multicenter, observational study. All patients with streptococcal IE admitted from 2016 to 2018 were enrolled. Mortality and incidence of acute kidney injury (AKI) were compared between Group A (standard of care, SoC) and Group B (daptomycin-based aminoglycoside-sparing combination therapy). Fifty-four patients were enrolled, 33 in Group A and 21 in Group B. Mortality was 2/33 (6%) in Group A and 0 in Group B ( p  = 0.681); AKI incidence was 8/33 (24%) in Group A and 0 in Group B ( p  = 0.04). Daptomycin-based aminoglycoside-sparing combination therapy appears to be promising for the treatment of streptococcal endocarditis because of similar efficacy compared with SoC and significantly reduced incidence of AKI.

Background and Objective: When administered for severe infections in intravenous drug users (IDUs) at a daily dose of 6 mg/kg, daptomycin displayed abnormal pharmacokinetic parameters compared with those seen in healthy volunteers; specifically, decreased trough and maximum concentrations (C trough ; C max ) and increased clearance (CL). The objective of this study was to evaluate the pharmacokinetics and pharmacodynamics of daptomycin administered at a daily dosage of 12 mg/kg for Staphylococcus aureus infective endocarditis (IE) in patients concomitantly treated with methadone, and to compare the results with those published in the literature for healthy controls treated with the same daily dose., Methods: Antibiotic treatment included daptomycin (12 mg/kg daily) in combination with an antistaphylococcal β-lactam (cefazolin 2 g three times a day). The minimum inhibitory concentration (MIC) of Staphylococcus aureus isolated through blood cultures was used to calculate pharmacokinetic and pharmacodynamic parameters such as the ratio of the area under the concentration-time curve over 24 h to the MIC (AUC 0-24 /MIC) and C max /MIC., Results: Five IDUs hospitalized for IE were enrolled. The mean measured daptomycin C max and C trough were 54.1 μg/mL (CV: 0.32) and 8.7 μg/mL (CV: 0.59), respectively; the mean calculated AUC 0-24 was 742.7 μg × h/mL (CV: 0.31). The estimated average volume of distribution at the steady state (V d,ss ) and the half-life (t 1/2 ) were 316.5 mL/kg (CV: 0.53) and 14.4 h (CV: 0.30), respectively. The mean daptomycin clearance from plasma normalized for body weight (CL wp ) was 17.3 mL/(h × kg) (CV: 0.33). The calculated average C max and AUC 0-24 (183.7 µg/mL and 1277.4 µg × h/mL, respectively) were lower than and statistically significantly different from (p < 0.001 and p = 0.001, respectively) those expected for healthy volunteers., Conclusions: Treatment of Staphylococcus aureus IE in IDUs on methadone treatment requires the use of high daptomycin daily doses in order to achieve satisfactory pharmacodynamic parameters. Close monitoring of the daptomycin plasma concentration is suggested., (© 2021. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Purpose: This study evaluated the population pharmacokinetics of daptomycin in nonobese elderly patients with hypoalbuminemia and chronic kidney disease (CKD) using the glomerular filtration rate estimated from cystatin C (eGFRcys) and estimated its optimal dose., Methods: We performed population pharmacokinetic analysis of the unbound concentrations of daptomycin. The probability of target attainment of 90% for achieving an area under the concentration-time curve of unbound daptomycin at steady state/ minimum inhibitory concentration ratio of ≥66.6 was stochastically simulated., Results: In the population pharmacokinetic analysis of 25 patients aged ≥65 years, the two-compartment model using eGFRcys and age as covariates of clearance in central compartment of unbound daptomycin were optimal. The unbound fraction rate (fu) was 0.05-0.14. According to the Monte Carlo simulation, the optimal doses for patients with eGFRcys of 20-60 mL/min and aged 65-95 years were calculated as 200-500 mg q24h., Conclusion: These results suggest that establishing the dose using total concentrations may result in under- or overestimation caused by alterations in fu. The optimal dose for nonobese elderly patients with hypoalbuminemia and CKD depends on eGFRcys and age, and a standard dose may be insufficient for some patients.

What Is Known: Daptomycin is associated with a number of adverse effects including eosinophilic pneumonia, hypersensitivity reaction, myopathy, rhabdomyolysis, headache and transaminitis. The adverse effects of high-dose daptomycin have not been fully evaluated in patients with end-stage renal disease (ESRD)., Objective: To determine the incidence and characteristics of significant adverse effects in patients receiving high-dose daptomycin with severe renal dysfunction., Methods: A single-centre, retrospective study was conducted to assess safety outcomes of high-dose daptomycin in patients with an estimated creatinine clearance less than 30 mL/min. Adult patients aged 18 to 89 years admitted between 1 July 2015 and 1 July 2019 were eligible for inclusion. Patients must have received definitive daptomycin therapy with doses greater than or equal to 7.5 mg/kg based on actual body weight. The primary outcome was overall incidence of creatine phosphokinase (CK) elevation, myopathy and rhabdomyolysis., Results and Discussion: A total of 74 patients who received daptomycin therapy were screened with 50 included in the study. The population was well distributed in terms of gender (48% male, n = 24) with a median age of 61 (IQR, 48-67) years. The primary indication for daptomycin use was Gram-positive bacteremia. The median daptomycin dose was 750 (IQR, 600-875) mg, or 8.46 (IQR, 7.92-9.96) mg/kg based on actual body weight, with a median patient weight of 81 (IQR, 65-113) kg. The median duration of therapy was 27 (IQR, 14-42) days. One patient experienced significant CK elevation while on daptomycin therapy with rhabdomyolysis; however, daptomycin was continued as there was an alternative explanation for an elevated CK. One patient experienced daptomycin discontinuation due to CK elevation without meeting the definition for significant CK elevation., What Is New and Conclusion: In a cohort of patients with severe renal dysfunction treated with daptomycin 7.5 mg/kg or greater, significant CK elevation on daptomycin therapy was infrequently observed. Future research should confirm these findings, with special consideration for higher mg/kg dosages and/or obese populations., (© 2020 John Wiley & Sons Ltd.)

The use of daptomycin (DAP) in septic pulmonary emboli (SPE) remains controversial. We analyzed 29 cases of MRSA bacteremia complicated by SPE treated with DAP (n = 14) or DAP-ceftaroline fosamil (CPT; n = 15). Initial treatment with DAP monotherapy was found to have a success rate comparable with DAP-CPT (71% vs. 80%; p = 0.68).

The combination of vancomycin or daptomycin plus ceftaroline has showed synergistic results in vitro. This study aimed to investigate in vitro synergy of vancomycin or daptomycin plus ceftaroline for seven patients with daptomycin non-susceptible Staphylococcus aureus (SA) bacteremia Thirteen isolates from seven patients were evaluated: two methicillin-susceptible and five methicillin-resistant SA infections. All patients were treated with daptomycin and became non-susceptible (minimum inhibitory concentration (MIC) >1 μg/mL) with therapy or had resistant strains initially. Time kill experiments were completed with 0.25 × MIC, 0.5 × MIC, and 0.75 × MIC concentrations. No synergy was seen at 0.25 × MIC. Synergy was observed for 4 isolates with vancomycin plus ceftaroline and with daptomycin plus ceftaroline for 2 isolates at 0.5 × MIC. These results are in accordance with literature that supports synergistic combinations of daptomycin or vancomycin with ceftaroline for SA bacteremia. Daptomycin non-susceptible SA bacteremia presents a treatment challenge., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Abiotophia defectiva ( A. defectiva ) infectious endocarditis (IE) is a serious disease that usually requires lengthy treatment with a combination of amoxicillin and gentamicin. Since severe nephrotoxicity can be associated with prolonged administration of gentamicin, the alternative use of daptomycin in combination with amoxicillin can be considered. We present the case of a 51-year-old man that presented an A. defectiva endocarditis on an aortic bicuspidy. Diagnosis of cirrhosis was made simultaneously, and therefore gentamicin was counter-indicated. A combination of amoxicillin 12 g per day and daptomycin 700 mg (10 mg/kg) was administrated, with resolution of clinical, biological and echographic abnormalities, and no relapse after 1 year. In our experience, amoxicillin with daptomycin could be an alternative in case of A. defectiva IE with counter-indication to aminoglycosides.

Background: The combination of daptomycin (DAP) plus ampicillin (AMP), ertapenem (ERT), or ceftaroline has been demonstrated to be efficacious against a DAP-tolerant Enterococcus faecium strain (HOU503). However, the mechanism for the efficacy of these combinations against DAP-resistant (DAP-R) E. faecium strains is unknown., Methods: We investigated the efficacy of DAP in combination with AMP, ERT, ceftaroline, ceftriaxone, or amoxicillin against DAP-R E. faecium R497 using established in vitro and in vivo models. We evaluated pbp expression, levels of penicillin-binding protein (PBP) 5 (PBP5) and β-lactam binding affinity in HOU503 versus R497., Results: DAP plus AMP was the only efficacious regimen against DAP-R R497 and prevented emergence of resistance. DAP at 8, 6, and 4 mg/kg in combination with AMP was efficacious but showed delayed killing compared with 10 mg/kg. PBP5 of HOU503 exhibited amino acid substitutions in the penicillin-binding domain relative to R497. No difference in pbp mRNA or PBP5 levels was detected between HOU503 and R497. labeling of PBPs with Bocillin FL, a fluorescent penicillin derivative, showed increased β-lactam binding affinity of PBP5 of HOU503 compared with that of R497., Conclusions: Only DAP (10 mg/kg) plus AMP or amoxicillin was efficacious against a DAP-R E. faecium strain, and pbp5 alleles may be important contributors to efficacy of DAP plus β-lactam therapy., (© The Author(s) 2020. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)

Scope: This position paper describes the view adopted by EUCAST on the role of daptomycin in the treatment of serious infections caused by Enterococcus species., Background: High-dose daptomycin is considered effective in the treatment of enterococcal bloodstream infection (BSI) and endocarditis, although published clinical experience with the latter condition is limited., Methods: EUCAST reviewed the available published data on pharmacokinetics-pharmacodynamics (PK-PD), resistance selection, clinical efficacy and safety for the use of 10-12 mg/kg/day of daptomycin for these conditions, noting that the doses licensed by the European Medicines Agency are only 4-6 mg/kg/day, and only for infections caused by Staphylococcus aureus., Findings and Recommendations: The PK-PD evidence shows that, even with doses of 10-12 mg/kg/day, it is not possible to treat infections caused by isolates at the upper end of the wild-type distributions of Enterococcus faecalis (with MICs of 4 mg/L) and E. faecium (with MICs of 4 or 8 mg/L). For this reason, and because there are ongoing issues with the reliability of laboratory testing, EUCAST lists daptomycin breakpoints for Enterococcus species as "IE"-insufficient evidence. EUCAST advises increased vigilance in the use of high-dose of daptomycin to treat enterococcal BSI and endocarditis. Additional PK-PD studies and prospective efficacy and safety studies of serious Enterococcal infections treated with high-dose daptomycin may permit the setting of breakpoints in the future., (Copyright © 2020 European Society of Clinical Microbiology and Infectious Diseases. All rights reserved.)

Herein, we describe a rare case of Corynebacterium jeikeium endocarditis that silently progressed in a 65-year-old man undergoing hemodialysis. Because routine monthly blood examination revealed high C-reactive protein levels, blood cultures were collected, although he had no symptom and was afebrile. After 2 days, a Gram-positive rod was detected in one set of the blood culture. Furthermore, transthoracic echocardiography revealed new aortic regurgitation (AR) and vegetations, and, therefore, infective endocarditis was suspected. Transesophageal echocardiography showed vegetations with a maximum diameter of 8 mm on his aortic valve, with some valve destruction. C. jeikeium was identified in three sets of blood cultures. Administration of daptomycin was started because he had vancomycin allergy. Judging from the high risk of embolization due to vegetations, emergency aortic valve replacement was performed on the second day. C. jeikeium was detected in a resected cardiac valve specimen and blood. This case emphasizes that physicians should always consider the possibility of infective endocarditis even in hemodialysis patients without any symptoms.

Introduction: Observational and randomized controlled trials of the combination of vancomycin or daptomycin with a beta-lactam (BL) in patients with methicillin-resistant Staphylococcus aureus (MRSA) bacteremia have shown conflicting results on patient outcomes., Objectives: The primary purpose of this meta-analysis was to compare clinical failure with the combination of vancomycin or daptomycin with a BL versus vancomycin or daptomycin monotherapy in MRSA bacteremia or endocarditis., Methods: A systematic literature search of PubMed, Embase, CINAHL, and meeting proceedings was conducted from inception through February 11, 2020, to identify relevant studies. The primary outcome was clinical failure and secondary outcomes were mortality, nephrotoxicity, and bacteremia. The meta-analysis was performed using Comprehensive Meta Analysis (version 3.0) with a random effects model. Outcomes were reported as odds ratios (ORs) with corresponding 95% confidence intervals (CIs)., Results: Nine studies of 1636 patients receiving vancomycin or daptomycin monotherapy versus the combination of vancomycin or daptomycin plus BL for MRSA bacteremia were included. Results showed combination therapy was associated with significantly lower clinical failure rates (OR 0.56, 95% CI 0.39-0.79, I 2  = 26.22%, p=0.001). Improvement in clinical failure was driven by lower rates of bacteremia relapse and persistence. However, no difference was seen with mortality., Conclusions: Combination therapy with vancomycin or daptomycin plus BL for MRSA bacteremia showed lower clinical failure rates, however, no significant difference was seen in mortality., (© 2020 Pharmacotherapy Publications, Inc.)

Case: A 32-year-old man developed lumbar discitis and osteomyelitis after receiving a cell-based injection for the treatment of degenerative disc disease. Initial cultures were negative, but he continued to worsen, and a repeat set of cultures was taken. On day 10, Cutibacterium acnes was isolated. He was then successfully treated with 12 weeks of intravenous antibiotics., Conclusions: There is minimal regulation on the preparation or administration of cell-based interventions. It is important to consider slow growing organisms such as C. acnes in patients presenting with spinal infection with insidious onset after these treatments.

Objective: To compare the efficacy and safety of standard-dose (SD) daptomycin with those of high-dose (HD) daptomycin in complicated skin and soft tissue infections (cSSTIs) in an Asian population., Materials and Methods: Patients from three medical centers diagnosed with cSSTIs were screened in the clinical information system. Patients included in the analysis were divided into two groups: those who received daptomycin at doses ≥ 6 mg/kg (HD group) and those receiving 4 mg/kg (SD group). The demographics and clinical treatment information were analyzed., Results: Overall, 155 patients were recruited, including 108 patients in the SD group and 47 patients in the HD group. The rate of healthcare-associated infections was higher in the HD group (61.70% vs. 37.04%), demonstrating a statistically significant difference (P = 0.005). Compared with the SD group, the HD group had statistically significant early clinical stabilization (72.34% vs 52.78%, P = 0.023). The results of the multivariate analysis indicated that HD daptomycin was an independent effector for early clinical stabilization (HR=0.394, P < 0.001). The rate of drug-related adverse events was equally distributed in the HD and SD groups (36.17% vs. 26.85%, P = 0.243)., Conclusion: Compared with SD daptomycin, HD daptomycin increased the rate of early clinical stabilization in Asian patients with cSSTIs, whereas the incidence of adverse events did not increase., (Copyright © 2020 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

The objective of this study was to evaluate the efficacy of various daptomycin dosing regimens against Staphylococcus aureus and Enterococcus faecium in pediatric patients with proven/suspected gram-positive infection. Monte Carlo simulations (MCSs) were conducted using pharmacokinetic (PK) parameters and pharmacodynamic (PD) data to determine the probabilities of target attainment and cumulative fractions of response in terms of area under the concentration curve/minimum inhibition concentration (MIC) targets of daptomycin. According to the results of the MCSs, currently approved pediatric dosage regimens were sufficient against Staphylococcus aureus with MIC ≤ 0.5 μg/mL for all pediatric patients, but poor when MIC ≥ 1 μg/mL except for adolescents (12-17 years) who need a dosage of ≥10 mg/kg/day at MIC = 1 μg/mL. For Enterococcus faecium with MIC ≤ 4 μg/mL, the recommended dosage of 8-12 mg/kg/day in adults was enough for adolescents, but not subjected to younger pediatric patients. Furthermore, based on MIC distributions obtained from the European Committee on Antimicrobial Susceptibility Testing, the approved high-dose regimen should be recommended for infants aged 3-12 months, children (2-11 years), and adolescents to achieve better clinical efficacy against methicillin-resistant Staphylococcus aureus. In addition, the dosage of 8-12 mg/kg/day was powerful against Enterococcus faecium for adolescents; however, only the highest dosage of 12 mg/kg/day was effective for infants aged 3-12 months and children. All the simulated regimens were not optimal for infants aged 13-24 months. These PK/PD-based simulations rationalize and optimize the dosage regimens of daptomycin against Staphylococcus aureus and Enterococcus faecium in pediatric patients., (© 2020, The American College of Clinical Pharmacology.)

Previous studies and the concentration-dependent antibacterial actions of daptomycin suggested that a high dose would be needed for difficult-to-treat infections in burn patients. Here, we evaluated the effects of administration of low and high doses of daptomycin in patients with severe burn injuries. The study retrospectively analyzed 10 patients with severe burn injuries, using pharmacokinetic (PK) and pharmacodynamic (PD) evaluations of daptomycin doses given to combat serious infections. Daptomycin was administered as a single dose or by multiple doses intravenously at a standard dose of 6 mg/kg/d or a high dose of 12 mg/kg/d for 7 to 14 days. The serum concentrations of daptomycin from patients were analyzed by liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS). Burn injury patients treated with high-dose daptomycin had a linear PK profile and a negative correlation between the AUC0-24 and Baux score (R2 = .953 and R2 = .801). The Cmax, AUC0-24, and t(h)½ increased significantly compared with patients given a standard dose. The efficacy of daptomycin against Staphylococcus aureus showed significantly higher rates of (AUC0-24)/MIC and Cmax/MIC after high-dose daptomycin compared with the standard dose, reflected in a significant correlation between a high dose and the Baux score (r = .976, P < .001). Positive S. aureus cultures from two of three high-dose and none of two daptomycin low-dose patients converted from positive to negative after therapy. No serious adverse events or discontinuation of the drug occurred during the treatment period. Daptomycin doses up to 12 mg/kg/d were well tolerated in Chinese patients with severe burn injuries, which were complicated by infections with S. aureus., (© The Author(s) 2020. Published by Oxford University Press on behalf of the American Burn Association.)

What Is Known and Objective: Daptomycin-induced creatinine phosphokinase (CPK) elevation is reported to be associated with its trough level (C trough ; breakpoint of 24.3 μg/mL). However, even with high-dose treatment (ie, > 8 mg/kg), the safety of daptomycin treatment is widely demonstrated with low or no significant incidence of CPK elevation or other adverse effects, despite the possibility of C trough above 24.3 μg/mL. Therefore, we questioned the clinical significance of C trough levels of 24.3 μg/mL. In this study, we retrospectively evaluated the significance of C trough in the clinical setting, in addition to completing a retrospective safety assessment of daptomycin utilizing electronic health records., Methods: Patients who had received daptomycin treatment for > 4 days from July 2011 to June 2015 were enrolled. Serum daptomycin levels, including C trough and peak (C peak ), were measured by high-performance liquid chromatography equipped with a photodiode array. To evaluate the safety, patients' characteristics and relevant laboratory test values were reviewed retrospectively using an electronic medical record system., Results and Discussion: A total of 52 therapeutic cases for 46 patients were identified; of these, C trough and C peak levels were measured in 27 and 28 cases, respectively, and 6 patients received multiple courses of daptomycin treatment. The median age of the 52 patients was 68 years (range: 19-88 years), and 14 patients initially had an estimated creatinine clearance of less than 30 mL/min. Seven cases indicated a C trough of above 24.3 μg/mL; however, none of these presented CPK elevation, which meets with the study definition for abnormality. Furthermore, of the two patients with abnormal CPK elevations, only one patient had a measured C trough (of 10.9 μg/mL). Their CPK abnormalities were temporal and did not result in treatment discontinuation. The other four patients discontinued daptomycin treatment due to suspicions of adverse effects. Of the discontinued patients, two had measured C trough levels; these were 8.6 and 8.1 μg/mL. All patients with abnormal CPK elevation or treatment discontinuation exhibited C trough levels lower than 24.3 μg/mL. In this study, two patients receiving high-dose daptomycin (ie, 9.4 and 10.0 mg/kg) had observed C trough levels similar to patients who received doses of daptomycin < 9 mg/kg., What Is New and Conclusions: The safety of daptomycin treatment was suggested in this study. C trough level of 24.3 μg/mL was not suggested as a significant clinical index for the incidence of CPK elevation, adverse effects or treatment discontinuation. Thus, acceptable tolerability towards higher C trough levels than 24.3 μg/mL was also suggested, though further studies are required. On the other hand, low levels of daptomycin in blood were unexpectedly observed in two cases, despite the high-dose treatments. Accordingly, the monitoring of serum daptomycin levels may also be useful to assess cases in which subtherapeutic levels were achieved., (© 2019 John Wiley & Sons Ltd.)

High doses of daptomycin (DAP) (>6 mg/kg/day) have been preliminarily recommended in recent practical guidelines for methicillin-resistant Staphylococcus aureus infection, to achieve better clinical effects. While such doses can elevate the plasma trough concentration (Cmin) of DAP, there is an associated risk of creatine phosphokinase (CPK) elevation warranting further investigation. In the current study relationships between DAP Cmin and CPK elevation were investigated, and optimal DAP doses were determined. Plasma DAP concentrations were measured in 20 patients. Logistic regression analysis was performed to assess relationships between DAP Cmin and CPK elevation, then a population pharmacokinetic model of DAP was developed. To determine an optimal DAP dose a Monte Carlo simulation (MCS) was performed to minimize the risk of CPK elevation and maximize the probability of successful treatment. In logistic regression analysis DAP Cmin was significantly associated with CPK elevation (odds ratio 1.21, p = 0.048). With respect to dose-dependent increases in the probability of CPK elevation and exposure to DAP, MCS estimated an optimal DAP dose of 4-6 mg/kg/day, corresponding to a minimum inhibitory concentration (MIC) of ≤0.5 μg/mL. For an MIC of 1 μg/mL, MCS estimated an optimal DAP dose of 10 mg/kg/day. However, the probability of CPK elevation associated with high doses of DAP was higher than that associated with the approved doses. In cases where high doses of DAP are administered, close CPK monitoring is required and therapeutic drug monitoring of DAP may be desirable., (Copyright © 2019 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.)

Background: Infection of vascular grafts is a life-threatening complication in cardiovascular surgical procedures. This experimental study tested the efficacy and possible harmful effects of daptomycin pre-treatment in vivo in prevention of vascular graft infection caused by Staphylococcus aureus. Methods: Polyethylene terephthalate (PET) patches (5 × 7 mm) were sewn on the infra-renal abdominal aorta of 32 New Zealand White rabbits. Before implantation, patches either were pre-treated for 15 min with daptomycin in one group (n = 13) or left untreated in the other group (n = 13) before contamination with 100 mcL bacterial solution (1 × 10 10 colony-forming units [CFU] per mL). Six animals with uninfected patches without (n = 3) or with (n = 3) daptomycin pre-treatment served as controls. On postoperative day seven, all patches were explanted, washed with phosphate buffered saline, and sonicated to release viable adherent bacteria. The CFUs were quantified and aortic tissues were histologically examined. In addition, bacterial adherence on the patches was analyzed using scanning electron microscopy (SEM). Results: In the daptomycin pre-treatment group, significantly reduced numbers of CFUs on the patches were observed, compared with non-pre-treated patches (3.21 × 10 2  ± 1.02 × 10 3 mL -1 vs. 5.18 × 10 5 ± 1.05 × 10 6 mL -1 ; p < 0.001). Peri-vascular abscesses were visible in all rabbits with S. aureus infected patches, whereas no signs of inflammation were found in the daptomycin pre-treatment group or the control groups. Conclusions: Daptomycin showed excellent in vivo antibacterial activity against vascular graft infection caused by S. aureus , compared with non-pre-treated grafts, resulting in a significant reduction in bacterial infection and prevention of abscess formation. No harmful effects of the antibiotic pre-treatment could be observed.

Vancomycin and daptomycin are often used in outpatient parenteral antimicrobial therapy for gram-positive coverage. Vancomycin's narrow therapeutic window poses challenges. We retrospectively assessed acute kidney injury (AKI) and other adverse drug events in outpatient parenteral antimicrobial therapy patients receiving vancomycin or daptomycin at home after hospital discharge. Among 191 patients included, AKI was the most common adverse drug event. Early antibiotic discontinuation and AKI were more frequent in the vancomycin group. Vancomycin use (odds ratio [OR], 4.57; 95% confidence interval [CI], 1.02-20.51); p = 0.04], female sex (OR, 3.28; 95%CI, 1.41-7.67; P < .01), and longer hospitalization (OR, 1.06; 95%CI, 1.01-1.11; P = .02] independently predicted moderate-to-severe AKI. In the vancomycin group, trough concentrations increased after discharge, and were higher in female compared to male patients, and in those who developed moderate-to-severe AKI compared to those who did not. Female sex (OR, 8.37; 95%CI, 2.35-29.82; P < .01) and higher concentrations (OR, 1.12; 95%CI, 1.05-1.19; P < .01) predicted moderate-to-severe AKI in patients receiving vancomycin. In conclusion, premature antibiotic discontinuations and nephrotoxicity are more frequent in patients treated at home with vancomycin compared to daptomycin. Among patients receiving vancomycin, plasma concentrations increased after hospital discharge and predicted moderate-to-severe AKI. Women had higher vancomycin concentrations and higher risk for AKI., (© 2019, The American College of Clinical Pharmacology.)

This retrospective study is to evaluate the efficacy and safety of daptomycin (DAP) intermittent doses and the effectiveness of DAP loading dose in renal failure patients received DAP intermittent doses. One hundred and ninety-seven patients received DAP for at least 3 days from 2014 to 2017. Clinical and microbiological outcomes and the safety were assessed. A total of 183 patients (93, 60 and 30 patients received DAP daily dose, every 48 h dose and thrice per week dose) were included. DAP intermittent doses, such as every 48 h dose (28.3%) and thrice per week dose (30.0%), showed significantly higher mortality rates than that of DAP daily dose (6.5%) (p = 0.0320). Especially for bacteremia patients, significantly higher mortality was admitted, compared with patients received DAP daily doses (p = 0.0160). Moreover, patients received DAP intermittent doses were admitted slower improvements of their inflammation after DAP therapy started, compared with patients received daily dose. Additionally, DAP loading dose for renal failure patients decreased their mortality and improved patients' inflammation early. Especially for patients received DAP thrice per week dose, they showed significantly lower mortality than patients received non-loading dose (p = 0.0306). Additionally, these clinical enhancements of DAP therapy with loading dose were admitted without any enhancements of its adverse effect risks, except alkaline phosphatase elevation, compared with non-loading dose. In conclusion, DAP intermittent doses showed poor clinical outcomes, compared with daily dose. Then, DAP loading dose would be better clinical option for patients received DAP intermittent doses., (Copyright © 2019 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.)

Objectives: Ceftobiprole is a relatively new cephalosporin with broad-spectrum activity and good tolerability. Despite its promising characteristics, to our knowledge, only two case reports, previously published also by some of us, is available concerning its administration for the treatment of infective endocarditis. Hereby we report our experience in this field., Methods: All the patients with infective endocarditis treated with ceftobiprole were enrolled., Results: 12 cases of endocarditis were treated with ceftobiprole, 11/12 in combination with daptomycin and 1/12 as monotherapy. Gram-positive bacteria were isolated in 12/12 patients; 3 cases were polymicrobial. Cure rate was 83% (10/12 patients). In 9/12 (75%) cases, patients were switched to ceftobiprole following failure of previous antimicrobial regimen. In 3/3 patients in which ceftobiprole was administered because of persistently positive blood culture, bacteraemia clearance was rapidly achieved., Conclusions: Ceftobiprole, especially in combination, could be a promising alternative treatment for infective endocarditis., (Copyright © 2019 International Society for Antimicrobial Chemotherapy. Published by Elsevier Ltd. All rights reserved.)

To predict the effects of combined use of antibiotics on their pharmacodynamics, the susceptibility of Staphylococcus aureus to daptomycin-rifampicin combinations was tested at concentration ratios equal to the ratios of daptomycin and rifampicin 24-h areas under the concentration-time curve (AUC 24 s) simulated in an in vitro dynamic model. In combination with rifampicin, daptomycin MICs decreased 2- to 31-fold, whereas rifampicin MICs were similar with or without daptomycin. The enhanced susceptibility of S. aureus to daptomycin combined with rifampicin resulted in both an increase of the actual AUC 24 /MIC ratios and also more pronounced antibacterial effects compared with single treatments. The areas between the control growth and time-kill curves (ABBCs) determined in combined and single daptomycin treatments were plotted against AUC 24 /MIC on the same graph (r 2 0.90). These findings suggest that the effects of daptomycin-rifampicin combinations can be predicted by AUC 24 /MICs of daptomycin using its MIC determined at pharmacokinetically derived daptomycin-to-rifampicin concentration ratios.

We investigated achievement of a target 24-h area under the concentration-time curve to minimum inhibitory concentration ratio (AUC/MIC) ≥666 and the factors influencing this ratio in patients who received daptomycin (DAP) for infectious disease treatment in a clinical setting. The target AUC/MIC was obtained in 6 patients (35.3%) at a 4-6 mg/kg dose (Group &#95;4-6 mg/kg ) and in 4 (18.2%) at a >6 mg/kg dose (Group &#95;>6 mg/kg ). There was a significant difference in clearance of DAP (CL &#95;DAP ) between these groups, but no other difference in characteristics. Multiple linear regression analysis was performed for prediction of AUC ≥666 based on patient factors and the presence or absence of sepsis. In a stepwise analysis, serum creatinine (SCr) was a significant predictor of AUC, but this parameter explained only 13% of the variance in achievement of the target AUC. These results show that the target AUC/MIC may or may not be achieved at the doses used in Group &#95;4-6 mg/kg and Group &#95;>6 mg/kg . Receiver operating characteristic analysis suggested that a CL &#95;DAP >0.450 L/hr may lead to failure to reach the target AUC/MIC. Therefore, regardless of dose, the efficacy of DAP should be monitored closely to prevent failure of infectious disease treatment, particularly because therapeutic drug monitoring of DAP is limited by difficulty measuring the DAP serum concentration at many medical facilities. Our findings are preliminary, and a further study is required to identify factors that increase CL &#95;DAP and to enable dose adjustment of DAP., (Copyright © 2019 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.)

Daptomycin (DAP) has a completely different mechanism of action compared to conventional methicillin-resistant Staphylococcus aureus (MRSA) drugs and is widely used clinically as the first-line drug for the treatment of skin soft tissue infection and sepsis caused by MRSA infection. However, the most serious side effects of DAP include renal dysfunction and rhabdomyolysis. Knowledge of the time sequence of localization of DAP in cells and tissues of animals may help in developing a better understanding of the actual overall pharmacokinetics of DAP. We prepared DAP-specific antibodies by immunizing mice with DAP-GMBS-BSA conjugate. The Anti-DAP antibody was specific for DAP, which enabled us to develop an immunocytochemical method for detecting the uptake of DAP in the rat kidneys. One hour after a single intravenous (i.v.) injection of DAP at 12 mg/kg, immunohistochemical observation showed a strong ring-like positive reaction in the cytoplasm immediately below the microvilli of proximal tubule epithelial cells. The distal tubules and collecting ducts contained DAP-positive and negative cells in the cross section of one tubule. Twenty-four hours after DAP administration, several strong positive reactions of different sizes were observed in the cytoplasm of epithelial cells at the proximal tubule. No staining was detected after 7 days. This study will be a useful tool for analyzing the pharmacokinetics of DAP.

New antimicrobial agents are being designed to treat infections of multidrug-resistant pathogens and have been introduced in the past few years, but there has been a worldwide increase in the incidence of vancomycin-resistant enterococci (VRE) infections, and treatment options are still limited. In this study, it was aimed to investigate the in vitro activity of vancomycin combined with daptomycin against 30 VRE strains. The minimum inhibitory concentration (MIC) values of antibiotics were determined using broth microdilution assay as described by the Clinical and Laboratory Standards Institute (CLSI). The activities of antibiotics in combination were assessed using a broth microcheckerboard method. In addition, 4 of the 30 strains were randomly selected to determine the time-kill curves at 1 × MIC concentrations and 2 of 4 strains at ½ × MIC concentrations. Viable counts were determined at 0-, 4-, 8-, 12-, 24-, 48-, and 72-hr intervals. This was accomplished by subculturing 0.1 mL from repetitive serial dilutions in Eppendorf tubes, followed by subculturing 0.1 mL from tubes onto Tryptic Soy Agar plates. All plates were incubated at 35°C for 24 hr. The synergistic effect was found 100% using the broth microcheckerboard method, and in strains tested using the time-kill method at both 1 × MIC and ½ × MIC concentrations. The results of this study suggest that this combination could be effective in the treatment of the VRE-associated infection.

In order to improve the stability of AgNPs and decrease the dosage of Daptomycin for killing bacteria, a reduced graphene oxide (rGO) was used for simultaneously anchoring AgNPs and Daptomycin to prepare rGO@Ag@Dap nanocomposites. In vitro experiments showed that the nanocomposites can efficiently kill four kinds of pathogenic bacteria, especially two kinds of Gram-positive bacteria (Staphylococcus aureus and Bacillus subtilis) through damaging cell integrity, producing ROS, decreasing ATP and GSH and disrupting bacterial metabolism. Against Gram-positive bacteria, the rGO@Ag@Dap nanocomposites showed a cooperative antibacterial effect. Moreover, in vivo experiments showed that rGO@Ag@Dap can improve the healing of wounds infected with bacteria by efficiently killing the bacteria on the wounds and further promoting skin regeneration and dense collagen deposition. In summary, the above results suggest that the cooperative function of AgNPs with Daptomycin can significantly improve antibacterial efficiency against infectious diseases caused by bacteria, especially for therapies made ineffective due to the drug resistance of pathogenic bacteria.

Background: Ventriculoperitoneal (VP) shunt infection, which is 1 of the most important complications of VP shunt is observed at a rate of 4%-17%. Staphylococcus epidermidis is the most common causative agent. Vancomycin-resistant Enterococcus (VRE) is an increasingly common nosocomial pathogen that rarely causes central nervous system infections globally. Current treatment options that have shown appreciable activity against various VRE infections include daptomycin, linezolid, inquinupristin/dalfopristin, and tigecycline. Daptomycin has a particular mode of action and a potent bactericidal activity, making it a useful addition to the clinician's antibiotic collection. Global surveillance data indicate <1.0% rates of daptomycin resistance in enterococci., Case Description: Here, we describe, to the best of our knowledge, the first case of successful intraventricular plus intravenous use of tigecycline to treat VP shunt infections caused by daptomycin resistant VRE faecium., Conclusion: Tigecycline is a life-saving option in the treatment of resistant nosocomial infections but it has not yet been approved for use and there are not enough data in terms of dose and side effects associated with its use in children., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Bacteriophage-derived lysins are being developed as anti-infective agents. In an acute osteomyelitis methicillin-resistant Staphylococcus aureus (MRSA) model, rats receiving no treatment or treatment with daptomycin, exebacase (CF-301), or daptomycin plus exebacase had means of 5.13, 4.09, 4.65, and 3.57 log 10 CFU/gram of bone, respectively. All treated animals had fewer bacteria than did untreated animals ( P  ≤ 0.0001), with daptomycin plus exebacase being more active than daptomycin ( P  = 0.0042) or exebacase ( P < 0.001) alone., (Copyright © 2019 American Society for Microbiology.)

Daptomycin is commonly prescribed in combination with other antibiotics for treatment of enterococcal bacteraemia. Whilst a free drug area under the concentration-time curve to minimum inhibitory concentration (fAUC/MIC) ratio >27.4 is associated with 30-day survival with daptomycin monotherapy, it is unknown whether receipt of other antibiotics affects this threshold. Data were pooled from seven published trials assessing outcomes in daptomycin-treated enterococcal bacteraemia, including patients receiving daptomycin (≥72 h) and any β-lactam, intravenous aminoglycoside, linezolid, tigecycline and/or vancomycin. Exposures were calculated using a published population pharmacokinetic model based on creatinine clearance, 90% protein binding and daptomycin Etest MIC. The fAUC/MIC threshold predictive of 30-day survival was determined by classification and regression tree analysis. Following pooling of data, 240 adults were included; 137 (57.1%) were alive at 30 days. A majority of patients were immunosuppressed (65.8%) and received a β-lactam (94.6%). Examining the threshold in low-acuity patients (n = 135) to control for co-morbidities, these patients were more likely to survive when fAUC/MIC >12.3 was achieved (63.2% vs. 20.0%; P = 0.015). The difference remained significant in a multivariable logistic regression model that controlled for infection source and immunosuppression (P = 0.017). This threshold is 2-fold lower than that observed with daptomycin monotherapy. Probabilities of threshold attainment using a 10 mg/kg/day dose were 100% for isolates with MICs ≤ 2 mg/L and 95.2% for a 12 mg/kg/day dose for MICs of 4 mg/L. These data support the use of high-dose daptomycin in combination with another antibiotic for treatment of enterococcal bacteraemia., (Copyright © 2019 Elsevier B.V. and International Society of Chemotherapy. All rights reserved.)

Background: There are currently few data concerning the cerebrospinal fluid (CSF) penetration of daptomycin in patients with healthcare-associated meningitis. This study aims (1) to better characterize the pharmacokinetics of daptomycin in humans during a 7-day intravenous (IV) therapy course, and (2) to study the penetration of daptomycin in the CSF after IV infusion at the dose of 10 mg/kg., Results: In this prospective observational study, we enrolled nine patients with an implanted external ventricular drainage and a diagnosis of a healthcare-associated meningitis. Daptomycin was administered at 10 mg/kg for a maximum of 7 days. The pharmacokinetic of daptomycin was studied using a two-compartment population/pharmacokinetic (POP/PK) model and by means of a nonlinear mixed effects modeling approach. A large inter-individual variability in plasma area under the curve (Range: 574.7-1366.3 h mg/L), paralleled by high-peak plasma concentration (C max ) (all values > 60 mg/L), was noted. The inter-individual variability of CSF-AUC although significant (range: 1.17-6.81 h mg/L) was narrower than previously reported and with a late occurrence of CSF-C max (range: 6.04-9.54 h). The terminal half-life between plasma and CSF was similar. t max values in CSF did not show a high inter-individual variability, and the fluctuations of predicted CSF concentrations were minimal. The mean value for daptomycin penetration obtained from our model was 0.45%., Conclusions: Our POP/PK model was able to describe the pharmacokinetics of daptomycin in both plasma and CSF, showing that daptomycin (up to 7 days at 10 mg/kg) has minimal penetration into central nervous system. Furthermore, the observed variability of AUC, t max and predicted concentration in CSF was lower than what previously reported in the literature. Based on the present findings, it is unlikely that daptomycin could reach CSF concentrations high enough to have clinical efficacy; this should be tested in future studies.