Safety & Efficacy of Daptomycin Versus Standard of Care (SOC) in 1 - 17 Year Olds With Staphylococcus Aureus Bacteremia (MK-3009-005)

S. aureus causes a series of invasive diseases in adults and children, including bacteremia. Infections due to S. aureus in children, particularly those due to methicillin resistant S. aureus (MRSA), are a growing world-wide public health concern.

Daptomycin, a cyclic lipopeptide antibacterial agent, shows rapid in vitro bactericidal activity with concentration-dependent killing for Gram-positive organisms, including S. aureus. Surveillance studies have demonstrated a daptomycin MIC90 of 0.5µg/ml for both methicillin-susceptible S. aureus (MSSA) and MRSA with >99% of MRSA isolates being categorized as susceptible by the Food and Drug Administration (FDA), European Committee of antimicrobial susceptibility testing (EUCAST) and Clinical and Laboratory Standards Institute (CLSI) breakpoints (5). Clinical trials in adults demonstrated that daptomycin was safe and efficacious in complicated skin and skin structure infections (cSSSI) and bloodstream infections caused by S. aureus, including right-sided infective endocarditis (RIE). However, information on the safety and efficacy of daptomycin for use in children is lacking.

The intent of this study in children is to confirm the safety of daptomycin at mean steady state systemic exposures (AUC) similar to those reported for adults treated at 6 mg/kg for bacteremia.

Inclusion criteria

To be included in this study, participants must:

• Sign a parental consent form; if appropriate, sign an assent form
• Be between 1 and 17 years of age
• Have proven or probable bacteremia caused by S. aureus based on the traditional culture result, rapid diagnostic test or Gram stain
• If female of childbearing potential, must not be pregnant or nursing and take appropriate measures to not get pregnant during the study
• If male, must take appropriate measures to not get partner pregnant
• Able to comply with the protocol requirements

Exclusion criteria

Participants will not be allowed into the study if they:

• Have received a certain amount of antibacterial therapy specific for current bacteremia unless it is demonstrated that the organism is resistant to the given antibacterial;
• Anticipate to require other antibiotics that may be potentially effective against S. aureus;
• Have shock or hypotension unresponsive to standard therapy;
• Have received an investigational product or have participated in an experimental procedure within 30 days;
• Have an intolerance or hypersensitivity to daptomycin;
• Have renal insufficiency;
• Have prior history or current evidence of muscle damage (rhabdomyolysis; significant CPK elevation);
• Have history of clinically significant muscular disease, nervous system or seizure disorder, including unexplained muscular weakness, history of peripheral neuropathy, Guillain-Barré or spinal cord injury;
• Have S. aureus pneumonia, empyema, meningitis, or endocarditis