The detection of photodegradation products of irinotecan (CPT-11, Campto, Camptosar), in clinical studies, using high-performance liquid chromatography/atmospheric pressure chemical ionisation/mass spectrometry.

摘要

A method for the detection of the photodegradation products of irinotecan (CPT-11, Campto, Camptosar) was developed using high-performance liquid chromatography (HPLC) with fluorescence detection and HPLC/atmospheric pressure chemical ionisation/mass spectrometry (HPLC/APCI/MS). Remnants of infusion solution as well as samples of urine and plasma collected at the end of the infusion of CPT-11 to cancer patients were screened for the five principal known photodegradation products (PDPs) of CPT-11. The concurrent use of standards of the PDPs with ion-extract HPLC/APCI/MS chromatograms enabled the identification of trace quantities of two PDPs in most samples analysed. However, similar analyses of fresh clinical drug solutions revealed that the PDPs were not generated significantly by exposure to light during the infusion period, but were already present in the drug ampoules. Furthermore, this appears to be the source of traces of PDPs detectable in urine and plasma of patients rather than metabolism, per se.