Retapamulin is a pleuromutilin antibiotic [1].
Retapamulin is developed for topical treatment of skin infections which is mainly caused by gram-positive organisms, β-hemolytic streptococci and coagulase-negative staphylococci. Retapamulin is especially used against those drug resistance strains. In the in vitro studies, retapamulin demonstrates potent activity and a broad spectrum. It shows excellent antimicrobial activities against S. aureus, S. epidermidis, S. saprophyticus, S. pyogenes, S. agalactiae and Viridans group streptococci with MIC50 values of 0.06μg/ml, 0.06μg/ml, 0.12μg/ml, 0.008μg/ml, 0.016μg/ml and 0.03μg/ml, respectively. Retapamulin plays its antibiotic role through binding to a unique site of the bacterial ribosome [1, 2].
References:
[1] Jones R N, Fritsche T R, Sader H S, et al. Activity of retapamulin (SB-275833), a novel pleuromutilin, against selected resistant gram-positive cocci. Antimicrobial agents and chemotherapy, 2006, 50(7): 2583-2586.
[2] Rittenhouse S, Biswas S, Broskey J, et al. Selection of retapamulin, a novel pleuromutilin for topical use. Antimicrobial agents and chemotherapy, 2006, 50(11): 3882-3885.