In:
Journal of Antimicrobial Chemotherapy, Oxford University Press (OUP), ( 2023-10-05)
Abstract:
The new definitions of antimicrobial susceptibility categories proposed by EUCAST in 2020 require the definition of standard and high dosages of antibiotic. For injectable β-lactams, standard and high dosages have been proposed for short-infusion regimens only. Objectives To evaluate dosages for β-lactams administered by prolonged infusion (PI) and continuous infusion (CI). Methods Monte Carlo simulations were performed for seven injectable β-lactams: aztreonam, cefepime, cefotaxime, cefoxitin, ceftazidime, piperacillin and temocillin. Various dosage regimens based on short infusion, PI or CI were simulated in virtual patients. Pharmacokinetic (PK) profiles and PTAs were obtained based on reference population PK models, as well as PK/pharmacodynamic targets and MIC breakpoints proposed by EUCAST. Alternative dosage regimens associated with PTA values similar to those of recommended dosages up to the breakpoints were considered acceptable. Results Adequate PTAs were confirmed for most EUCAST short-infusion dosage regimens. A total of 9 standard and 14 high dosages based on PI (3 to 4 h) or CI were identified as alternatives. For cefepime and aztreonam, only PI and CI regimens could achieve acceptable PTAs for infections caused by Pseudomonas spp.: 2 g q8h as PI of 4 h or 6 g/24 h CI for cefepime; 2 g q6h as PI of 3 h or 6 g/24 h CI for aztreonam. Conclusions These alternative standard and high dosage regimens are expected to provide antibiotic exposure compatible with new EUCAST definitions of susceptibility categories and associated MIC breakpoints. However, further clinical evaluation is necessary.
Type of Medium:
Online Resource
ISSN:
0305-7453
,
1460-2091
Language:
English
Publisher:
Oxford University Press (OUP)
Publication Date:
2023
detail.hit.zdb_id:
1467478-6
SSG:
15,3
