The first in a new class of antibacterial drugs called pleuromutilins, retapamulin binds to a site on the 50S subunit of the bacterial ribosome to inhibit protein synthesis.

• 该药是首个获准上市的截短侧耳素类新型抗生素药物，它与细菌核糖体50S亚基结合而抑制细菌蛋白的合成。