Article

Population pharmacokinetics of daptomycin.

Cubist Pharmaceuticals, Inc., Lexington, Massachusetts 02421, USA.
Antimicrobial Agents and Chemotherapy (Impact Factor: 4.57). 09/2004; 48(8):2799-807. DOI: 10.1128/AAC.48.8.2799-2807.2004
Source: PubMed

ABSTRACT Data from subjects in nine phase 1 (n = 153) and six phase 2/3 (n = 129) clinical trials were combined to identify factors contributing to interindividual variability in daptomycin pharmacokinetics (PK). Over 30 covariates were considered. A two-compartment model with first-order elimination provided the best fit for data on daptomycin concentrations in plasma over time. In the final population PK model, daptomycin plasma clearance (CL) was a function of renal function, body temperature, and sex. Of these factors, renal function contributed most significantly to interindividual variability. CL varied linearly with the estimated creatinine clearance. CL among dialysis subjects was approximately one-third that of healthy subjects (0.27 versus 0.81 liter/h). CL in females was 80% that in males; however, in clinical trials, the outcome was not affected by sex and therefore this effect is not considered clinically meaningful. The relationship with body temperature should be interpreted cautiously since the analysis included only a limited number of subjects who were hyperthermic. The volume of distribution of the peripheral compartment (V2) and intercompartmental clearance (Q) were linearly related to body weight. V2 increased approximately twofold in the presence of an acute infection. No factors were identified that significantly impacted V1. This analysis supports the dosing of daptomycin on a milligram-per-kilogram-of-body-weight basis and suggests that modified dosing regimens are indicated for patients with severe renal disease and for those undergoing dialysis.

0 Bookmarks
 · 
77 Views
  • [Show abstract] [Hide abstract]
    ABSTRACT: Methicillin-resistant Staphylococcus aureus (MRSA) remains a significant cause of morbidity in hospitalized infants. Over the past 15 years, several drugs have been approved for the treatment of S. aureus infections in adults (linezolid, quinupristin/dalfopristin, daptomycin, telavancin, tigecycline and ceftaroline). The use of the majority of these drugs has extended into the treatment of MRSA infections in infants, frequently with minimal safety or dosing information. Only linezolid is approved for use in infants, and pharmacokinetic data in infants are limited to linezolid and daptomycin. Pediatric trials are underway for ceftaroline, telavancin, and daptomycin; however, none of these studies includes infants. Here, we review current pharmacokinetic, safety and efficacy data of these drugs with a specific focus in infants.
    Expert Review of Clinical Pharmacology 04/2014;
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Continuous renal replacement therapy (CRRT) has given clinicians an important option in the care of critically ill patients. The slow and continuous dialysate and ultrafiltrate flow rates that are employed with CRRT can yield drug clearances similar to an analogous glomerular filtration rate of the native kidneys. Advantages such as superior volume control, excellent metabolic control, and hemodynamic tolerance by critically ill patients are well documented, but an understanding of drug dosing for CRRT is still a bit of a mystery. Although some pharmaceutical companies have dedicated postmarket research in this direction, many pharmaceutical companies have chosen not to pursue this information as it is not mandated and represents a relatively small part of their market. This lack of valuable information has created many challenges in the care of the critically ill patient as intermittent hemodialysis drug dosing recommendations cannot be extrapolated to CRRT. This drug dosing review will highlight factors that clinicians should consider when determining a pharmacotherapy regimen for a patient receiving CRRT.
    Seminars in Dialysis 03/2009; 22(2). · 2.25 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Infections in critically ill patients are associated with persistently poor clinical outcomes. These patients have severely altered and variable antibiotic pharmacokinetics and are infected by less susceptible pathogens. Antibiotic dosing that does not account for these features is likely to result in suboptimum outcomes. In this Review, we explore the challenges related to patients and pathogens that contribute to inadequate antibiotic dosing and discuss how to implement a process for individualised antibiotic therapy that increases the accuracy of dosing and optimises care for critically ill patients. To improve antibiotic dosing, any physiological changes in patients that could alter antibiotic concentrations should first be established; such changes include altered fluid status, changes in serum albumin concentrations and renal and hepatic function, and microvascular failure. Second, antibiotic susceptibility of pathogens should be confirmed with microbiological techniques. Data for bacterial susceptibility could then be combined with measured data for antibiotic concentrations (when available) in clinical dosing software, which uses pharmacokinetic/pharmacodynamic derived models from critically ill patients to predict accurately the dosing needs for individual patients. Individualisation of dosing could optimise antibiotic exposure and maximise effectiveness.
    The Lancet Infectious Diseases 04/2014; · 19.97 Impact Factor

Full-text (2 Sources)

Download
22 Downloads
Available from
May 22, 2014