Daptomycin: a comparison of two intravenous formulations

Daptomycin is a cyclic lipopeptide antibacterial agent with potent bactericidal activity against a broad range of Gram-positive organisms. In 2003, daptomycin for injection received approval from the US Food and Drug Administration (FDA) for the treatment of patients with complicated skin and skin structure infections (cSSSIs); in 2006, it was approved for the treatment of patients with Staphylococcus aureus bacteremia, including those with right-sided infective endocarditis caused by methicillin-susceptible and methicillin-resistant isolates. In 2016, the FDA approved a new formulation of daptomycin for injection (daptomycin RF) for the same indications. The efficacy and safety of daptomycin for injection have been established in pivotal clinical trials, and the findings of nonclinical studies indicate that both formulations of daptomycin for injection are equivalent. Herein we refer to the new daptomycin formulation as daptomycin RF to distinguish it from the original formulation. Daptomycin RF provides clinicians and clinical pharmacists with a product that offers improved stability and more rapid, in-vial reconstitution with either sterile or bacteriostatic water for injection, while maintaining the same antibacterial coverage. Here we discuss the rationale for and the potential value of daptomycin RF, and briefly review the similarities and differences between the original formulation of daptomycin and daptomycin RF.