Retapamulin

Retapamulin (SB-275833) is a topical antibiotic that binds Staphylococcus aureus and E. coli ribosomes with a Kd of 3 nM. Retapamulin can be used in researches of atopic dermatitis and prostate cancer^[1][2][8]. In Vitro:Retapamulin demonstrates excellent in vitro activity against Methicillin (HY-121544)-susceptible Staphylococcus aureus and Methicillin-resistant S. aureus (MRSA) strains, but not against MRSA isolates harbouring the cfr gene^[3].
Retapamulin inhibits Streptococcus pyogenes isolates, with MICs ranging from ≤0.015 to 0.12 μg/mL^[4].
Retapamulin inhibits Staphylococcus aureus and Streptococcus pyogenes, with MIC₉₀s of 0.12 and ≤0.03 μg/mL, respectively^[5].
Retapamulin inhibits total viable cell (TVC), protein synthesis and 50S subunit synthesis of wild-type Staphylococcus aureus strain RN1786 with IC50s of 12 , 5 and 27 ng/mL, respectively^[6].
Retapamulin inhibits cytopathic effect, papain-like protease, and M^PRO enzymes of SARS-CoV-2 with IC₅₀ values of 4.23, 0.88 and 1.25 µM^[7].
Retapamulin (0-10 μM, 3 days) inhibits cell invasion by more than 50% at 0.1 μM in PC-3-KQ cells^[8].
Retapamulin (0-500 μg/mL, 16 h) shows cytotoxicity in BRL-3A cells, with an IC₅₀ of 49 μg/mL^[9].
In Vivo:Retapamulin (1%, applied topically to the lesion area, twice daily for 3 days or 6 days) reduces meticillin-resistant Staphylococcus aureus (MRSA) loads in a murine superficial skin wound infection model^[10].