Retapamulin is a new topical pleuromutilin antibiotic for the treatment of skin 
and skin-structure infections, including impetigo. In vitro studies indicate 
that retapamulin has a unique mode of action that minimizes the potential for 
target-specific cross-resistance with other antibacterials and a limited 
potential for resistance development. Its spectrum of activity includes the most 
likely causative pathogens Staphylococcus aureus and Streptococcus pyogenes. In 
the Global Surveillance Program, retapamulin was highly active in vitro, 
including against strains of S. aureus resistant to methicillin, mupirocin or 
fusidic acid. In clinical studies, retapamulin was noninferior to fusidic acid 
and oral cefalexin, achieving per-pathogen success rates of 86-99%. Topical 
retapamulin has a good safety profile and is associated with high patient 
compliance.