Spiramycin pharmacokinetics

Among the many antibiotics isolated from the actinomycetes isthe group of chemically related compounds called the mac-mlides. In I9S0, picromycin, the first of this group to be identified as a macrolide compound, was first reported. In 1952. erythromycin and carbomycin were reported us new antibiotics, and they were followed in subsequent years by other macrolides. Currently, more than 40 such compounds ate known, and new ones are likely to appear in the future. Of all of these, only two, erythromycin and oleandomycin, have been available consistently for medical use in the United States. In recent years, interest has shifted away from novel macrolides isolated from soil samples (e.g.,. spiramycin, josamycin, and rosamicin), all of which thus far have proved to be clinically inferior to erythromycin and semisynthetic derivatives of erythromycin (e.g., clarithromycin and azithromycin), which have superior pharmacokinetic properties due to their enhanced acid stability and improved distribution properties. 

Neospiramycins are demycarosyl derivatives of spiramycins and consist of a platenolide ring, o-mycaminose, and o-forosamine. Neospiramycin I shows antibacterial activity similar or superior to that of spiramycin in vitro but is practically inactive in vivo. The pharmacokinetic profiles of the two compounds appear to differ. 

Brion N, Kollenbach K, Marion MH, Gregoire A, Advenier C, Pays M. Effect of a macrolide (spiramycin) on the pharmacokinetics of L-dopa and carbidopa in healdiy volunteers. Clin Neuropharmacol ( 992) 15, 229-35. 

Vemillet L, Bertault-Peres P, Berland Y, Barradas J, Durand A, Olmer M. Lack of effect of spiramycin on cyclosporin pharmacokinetics. BrJ Clin Pharmacol (1989) 27, 789-94. 

An LC-MS-MS method for simultaneous determination of metronidazole and spiramycin I concentrations in human plasma, saliva, and gingival crevicular fluid (GCF), preceded by liquid-liquid extraction (LLE). Omidazole is used as an internal standard. A C18 column is used with an eluent of acetonitrile, water, and formic acid. Intra- and interbatch precision 7, 12, and 9% in plasma, saliva, and GCF, respectively. Accuracy was lowest in saliva (15.4%) and better in plasma (8.7%) or in GCF (10.7%). Linearity, specificity, recovery, matrix effect, dilution process, stability in human plasma and saliva after three freeze-thaw cycles, stability in human plasma and saliva at ambient temperature, and stability of the extracts in the automatic injector of the HPLC system have been studied. Useful for pharmacokinetic evaluations. 

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