Activity of dalbavancin tested against Gram-positive clinical isolates causing skin and skin-structure infections in paediatric patients from US hospitals (2014-2015).

This study provides an in vitro analysis of dalbavancin activity against isolates causing skin and skin-structure infections (SSSIs) in children. A total of 770 Staphylococcus aureus, 167 β-haemolytic streptococci (BHS), 42 coagulase-negative staphylococci (CoNS), 25 Enterococcus faecalis and 13 viridans group streptococci (VGS) were collected from children (<18years old) in the USA (2014-2015). Dalbavancin had MIC50/90 values of 0.03/0.06μg/mL against S. aureus and CoNS, including methicillin-resistant (MRSA) and -susceptible (MSSA) isolates. Dalbavancin MICs were 8-32-fold lower than those of daptomycin (MIC50/90, 0.25/0.5μg/mL), vancomycin (MIC50/90, 0.5/1μg/mL) and linezolid (MIC50/90, 1/1μg/mL) against MRSA. These agents showed 100.0% susceptibility against MRSA, and clindamycin also had a high (92.7%) susceptibility rate. Dalbavancin (MIC50/90, 0.03/0.06μg/mL) and daptomycin (MIC50/90, 0.25/0.5μg/mL) were the most active agents against CoNS. When tested against E. faecalis, dalbavancin was up to 32-fold more active than ampicillin (MIC50/90, ≤0.5/1μg/mL), daptomycin (MIC50/90, 1/1μg/mL), linezolid (MIC50/90, 1/2μg/mL) and vancomycin (MIC50/90, 1/2μg/mL). Dalbavancin (MIC50/90, 0.008/0.03μg/mL), ceftriaxone (MIC50/90, ≤0.06/≤0.06μg/mL) and penicillin (MIC50/90, ≤0.06/≤0.06μg/mL) were the most active against BHS. VGS isolates were susceptible to dalbavancin (MIC100, 0.03μg/mL), with MICs 32-64-fold lower than daptomycin (MIC50/90, 0.5/0.5μg/mL), linezolid (MIC50/90, 0.5/1μg/mL) and vancomycin (MIC50/90, 0.5/0.5μg/mL). Approved agents available for the treatment of SSSI in children are limited. Dalbavancin demonstrated potent in vitro activity against isolates causing SSSI in children. Developing dalbavancin for SSSI treatment in children is warranted, provided safety and tolerability are satisfactory.