Daptomycin (LY146032) for prevention and treatment of experimental aortic valve endocarditis in rabbits.

The efficacy of daptomycin (LY146032), a vancomycinlike lipopeptide antibiotic, was compared with that of antibiotics commonly in use for prevention and treatment of experimental aortic valve endocarditis in rabbits. Strains of Staphylococcus aureus. S. epidermidis, Streptococcus sanguis, and Enterococcus faecalis were used to establish endocarditis. A single 10-mg/kg dose of daptomycin and a single 25-mg/kg dose of vancomycin were both effective in prevention of endocarditis produced by strains of S. aureus and S. sanguis. Daptomycin was more effective than vancomycin for prevention of endocarditis caused by the strain of S. epidermidis. A single dose of daptomycin also was more effective in prevention of staphylococcal and enterococcal endocarditis than were single-dose regimens of cefazolin (100 mg/kg) and the combination of ampicillin (30 mg/kg) plus gentamicin (3 mg/kg), respectively. For treatment of endocarditis, daptomycin (10 mg/kg) as a single daily dose was as effective as regimens of either vancomycin or beta-lactam antibiotics for staphylococcal and enterococcal endocarditis. Daptomycin, however, was not as effective as a single daily dose of 600,000 U of procaine penicillin for endocarditis caused by the strain of S. sanguis.