Pyrotinibin vitrometabolite profiling via rat, dog and human hepatocytes using liquid chromatography–quadrupole/orbitrap mass spectrometry

Abstract

Rationale Pyrotinib is an irreversible EGFR/HER2 inhibitor that has shown antitumor activity and tolerance in the treatment of breast cancer. Studies focused on its metabolic pathways and major metabolites are insufficient. In the evaluation of drug safety and therapeutic use, metabolite characterization is critical. The metabolism of pyrotinib in vitro was studied utilizing rat, dog and human hepatocytes in this study. Methods Pyrotinib (10 μM) was incubated with hepatocytes in Williams' E medium. The metabolites were examined and profiled using ultrahigh‐performance liquid chromatography coupled with quadrupole/orbitrap high‐resolution mass spectrometry. The metabolite structures were deduced by comparing their precise molecular weights, fragment ions and retention times with those of the parent drug. Results A total of 16 metabolites, including 6 novel ones, were discovered and structurally described under the present conditions. Oxidation, demethylation, dehydrogenation, O‐dealkylation and glutathione (GSH) conjugation were all involved in the metabolism of pyrotinib in hepatocytes. The most predominant metabolic route was identified as GSH conjugation (M5). Conclusions This study generated valuable metabolite profiles of pyrotinib in several species, which will aid in the understanding of the drug's disposition in various species and in evaluating the contribution of metabolites to overall effectiveness and toxicity of pyrotinib.

Characterization of the metabolites of tirabrutinib generated from rat, dog and human liver microsomes using ultra‐high‐performance liquid chromatography combined with high‐resolution mass spectrometry

“…The proposed elemental composition was C 35 H 39 N 9 O 9 S, suggesting that M17 and M18 were GSH conjugates. MS/MS spectrum (Figure 6B) displayed two characteristic product ions at m/z 687.2336 (C 33 H 35 N 8 O 7 S + ) and 633.2231 (C 30 H 33 N 8 O 6 S + ), which were formed by the cleavage of glycinyl (−75 Da) and glutamyl (−129 Da), respectively, two characteristic neutral losses of GSH‐associated metabolites 13,14 . The product ion at m/z 389.1714 (C 21 H 20 N 6 O 2 + ) was identical to that of the parent.…”

“…MS/MS spectrum (Figure 6A) displayed characteristic neutral loss of glycinyl (−75 Da) and glutamyl (−129 Da), resulting in the product ions at m/z 703.2283 (C 33 H 35 N 8 O 8 S + ) and 649.2180 (C 30 H 33 N 8 O 7 S + ), respectively. Both characteristic ions demonstrated that M15 and M16 were GSH‐associated metabolites 13,14 . In addition, the product ion at m/z 389.1714 (C 21 H 20 N 6 O 2 + ) was identical to that of the parent, which indicated that oxygenation occurred at 1‐propynyl moiety.…”

“…À129 Da), respectively, two characteristic neutral losses of GSH-associated metabolites 13,14. The product ion at m/z 389.1714 (C 21 H 20 N 6 O 2…”