Transplacental transfer of vancomycin and telavancin

Objective: We sought to determine the bidirectional transfer and distribution of vancomycin and telavancin across the dually perfused term human placental lobule. Study Design: The technique of dually perfused placental lobule was used in its recirculating mode to determine the maternal to fetal (M→F) (n = 20) and fetal to maternal (n = 18) transfer of each antibiotic, which were coperfused with their radioactive isotopes. The concentrations of drugs were determined by liquid scintillation spectrometry. Results: In the M→F direction, the transfer of vancomycin (9.6 ± 4%) and telavancin (6.5 ± 2%) were low; however, telavancin retention by the perfused lobule was greater than that of vancomycin (P <.01). The normalized transplacental transfer of telavancin across the placental lobule in the fetal to maternal direction was higher than in the M→F direction (P <.01), suggesting the involvement of placental efflux transporters. Conclusion: The ex vivo perfusion experiments revealed low transfer of vancomycin and telavancin to the fetal circuit.