RT Journal Article
T1 In vitro effect of the presence of human albumin or human serum on the bactericidal activity of daptomycin against strains with the main resistance phenotypes in Gram-positives
A1 Cafini, Fabio
A1 Aguilar, Lorenzo
A1 González Hidalgo, Natalia
A1 Giménez, María José
A1 Torrico, Martha
A1 Alou Cervera, Luis
A1 Sevillano Fernández, David
A1 Vallejo, Paloma
A1 Prieto Prieto, José
AB Objectives: Bactericidal activity depends on antibiotic-bacteria couples, resistance phenotype and theoretically on protein binding. This work explores the influence of protein binding on the bactericidal activity of two antibiotics, daptomycin versus vancomycin, that exhibit, respectively, different C(max) (56 versus 25.5 mg/L), protein binding (91.7% versus 36.9%) and thus theoretical free-drug fractions (4.7 versus 16.1 mg/L).Methods: The effect of the presence of physiological concentrations of human albumin (4 g/dL) or human serum (90%) on the bactericidal activity of daptomycin was studied against Gram-positive isolates with troublesome resistance phenotypes [multidrug-resistant Streptococcus pneumoniae (MDRSP), methicillin-resistant Staphylococcus aureus (MRSA), heterogeneous vancomycin-intermediate MRSA (MRSA-hVI) and vancomycin-resistant Enterococcus faecium]. Killing curves (final inocula of approximately 10(7) cfu/mL) were performed using daptomycin and vancomycin concentrations similar to the C(max) obtained in serum.Results: Daptomycin was rapidly bactericidal (> or =3 log(10) initial inocula reduction) against S. pneumoniae and S. aureus, regardless of the strain tested or the presence of albumin or human serum (that slightly delayed bactericidal activity). Against vancomycin-susceptible or -resistant enterococci, daptomycin exhibited rapid bactericidal activity, delayed to 8 and 24 h, respectively, by human albumin. Vancomycin exhibited much slower bactericidal activity against MDRSP and methicillin-susceptible or -resistant S. aureus, but was never bactericidal against MRSA-hVI and vancomycin-susceptible or -resistant E. faecium.Conclusions: Daptomycin exhibited rapid bactericidal activity against the strains of the three Gram-positive species tested, regardless of resistance phenotype or the presence of physiological concentrations of albumin.
PB Oxford University Press
SN 0305-7453
YR 2007
FD 2007-04-05
LK https://hdl.handle.net/20.500.14352/107160
UL https://hdl.handle.net/20.500.14352/107160
LA eng
NO Cafini F, Aguilar L, González N, Giménez MJ, Torrico M, Alou L, Sevillano D, Vallejo P, Prieto J. In vitro effect of the presence of human albumin or human serum on the bactericidal activity of daptomycin against strains with the main resistance phenotypes in Gram-positives. J Antimicrob Chemother. 2007 Jun;59(6):1185-9.
NO Novartis Farmacéutica S.A.
DS Docta Complutense
RD 6 abr 2025