Quantification of the anti-influenza drug zanamivir in plasma using high-throughput HILIC-MS/MS.
Lindegardh N., Hanpithakpong W., Kamanikom B., Farrar J., Hien TT., Singhasivanon P., White NJ., Day NPJ.
BACKGROUND: parenteral zanamivir is a promising drug for the treatment of severe influenza. However, quantification of this polar drug in biological matrices has traditionally been difficult and the methods developed have been relatively insensitive. RESULTS: a high-throughput bioanalytical method for the analysis of zanamivir in human plasma using SPE in the 96-well plate format and LC coupled to positive MS/MS has been developed and validated according to US FDA guidelines. The method uses 50 microl of plasma and covers a large working range from 1-50, 000 ng/ml with a LOD of 0.50 ng/ml. CONCLUSION: this new LC-MS/MS assay is more sensitive than previous methods despite using a small plasma volume sample. It is particularly suitable for clinical studies on both parenteral and inhaled zanamivir.