Sevillano Fernández, DavidCalvo, AlmudenaGiménez, María JoséAlou Cervera, LuisAguilar, LorenzoValero, EvaCarcas, AntonioPrieto Prieto, José2024-07-292024-07-292004-12-01Sevillano D, Calvo A, Giménez MJ, Alou L, Aguilar L, Valero E, Carcas A, Prieto J. Bactericidal activity of amoxicillin against non-susceptible Streptococcus pneumoniae in an in vitro pharmacodynamic model simulating the concentrations obtained with the 2000/125 mg sustained-release co-amoxiclav formulation. J Antimicrob Chemother. 2004 Dec;54(6):1148-51.0305-745310.1093/jac/dkh463https://hdl.handle.net/20.500.14352/107186Objectives: To investigate the bactericidal activity against Streptococcus pneumoniae of simulated amoxicillin serum concentrations obtained in humans after 2000/125 mg sustained-release (SR) and 875/125 mg co-amoxiclav administered twice and three times a day, respectively. Methods: An in vitro computerized pharmacodynamic simulation was carried out and colony counts were determined over 24 h. Ten strains non-susceptible to amoxicillin (four of them exhibiting an MIC of 4 mg/L, five strains with an MIC of 8 mg/L and one strain with an MIC of 16 mg/L) were used. Results: With amoxicillin 2000 mg, an initial inoculum reduction >99.99% was obtained for strains with an MIC of 4 mg/L, > or =99% for strains with an MIC of 8 mg/L and 70.6% for the strain with an MIC of 16 mg/L at 24 h sampling time. At this sampling time, no reduction of initial inocula was obtained with amoxicillin 875 mg/8 h for two of the four strains with an MIC of 4 mg/L, three of the five strains with an MIC of 8 mg/L or for the strain with an MIC of 16 mg/L. Conclusions: The new co-amoxiclav 2000/125 mg SR formulation appears to offer advantages versus previous formulations with respect to bactericidal activity against current amoxicillin non-susceptible strains.engjournal article1460-2091https://doi.org/10.1093/jac/dkh463https://academic.oup.com/jac/article/54/6/1148/856052restricted access611.02β-lactamspneumococcal isolatesinocula decreaseMicrobiología médica2414 Microbiología