New Gram-positive antibiotics : better than vancomycin?

PURPOSE OF REVIEW: Despite concerns about vancomycin use in the treatment of multidrug-resistant Gram positives, evidence for better therapeutic outcomes with alternative antibiotics is lacking. This review focuses on recent advances. RECENT FINDINGS: Combination therapy with vancomycin-rifampin, although associated with better cure rates, resulted in the emergence of high rates of rifampin resistance. Of the newer anti-methicillin-resistant Staphylococcus aureus (MRSA) antibiotics, ceftopibrole, ortivancin and dalbavancin require further development prior to a further assessment by the United States Food and Drug Administration. Ceftaroline, telavancin and daptomycin were associated with comparable clinical cure rates compared with vancomycin in the treatment of complicated MRSA skin and soft tissue infections. In the treatment of hospital-acquired pneumonia, both telavancin and linezolid resulted in significantly greater clinical cure rates compared with vancomycin. Despite greater clinical cure rates, no difference in overall or infection-related mortality was detected. Of concern is the appearance of daptomycin and linezolid resistance following increased use. Toxicity profiles (especially of linezolid) are comparable to vancomycin provided short-duration therapy is prescribed. The first reports of daptomycin-induced acute eosinophillic pneumonia were described in 2010. SUMMARY: Based on current evidence, greater microbiological and clinical cure rates are achieved with alternative agents. However, these differences do not translate into mortality benefits compared with vancomycin for the treatment of S. aureus infections.