Bitespiramycin, has been shown to have a
therapeutic effect against respiratory tract
inflammation, including a potential effect against
COVID-19. A current clinical trial in China showed that
bitespiramycin was an effective treatment for severe
pneumonia and intracranial
infection. However, there is lack of an analytical method to elucidate the distribution of
bitespiramycin. In this study, a highly sensitive, rapid and reliable UPLC-MS/MS method was developed to comprehensively characterize the
bitespiramycin distribution in various bio-samples, which is significantly improved upon the published work. A rapid sample preparation method was developed by using
n-butanol as the
solvent to extract
bitespiramycin from different bio-samples. The extract was then directly analyzed by UPLC-MS/MS coupled with an alkaline-resistant column after centrifugation which avoids the time-consuming concentration process under
nitrogen and redissolution. The method was employed to accurately quantify
bitespiramycin and its metabolites in rat plasma, tissues, and human cerebrospinal fluid. Notably, the presence of
bitespiramycin and its metabolites was identified for the first time in various rat organs including brain, testis, bladder and prostate as well as in human cerebrospinal fluid. This newly developed approach shows great promise for drug distribution assays including other
antibiotics and can help elucidate the ADME of
bitespiramycin.