Validated HPLC-MS/MS method for quantitation of AMG 510, a KRAS G12C inhibitor, in mouse plasma and its application to a pharmacokinetic study in mice

AMG 510 is the first-in-class KRAS(G12C) inhibitor, currently in phase 2 clinical trials as an orphan drug to treat non-small cell lung cancer patients. We developed and validated a sensitive, selective, and high-throughput HPLC-MS/MS method for the quantitation of AMG 510 in mouse plasma per the regulatory guideline of the US Food and Drug and Administration. AMG 510 and the IS (MRTX-1257) were extracted from mouse plasma using tert-butyl methyl ether and chromatographed using an isocratic mobile phase (0.2% formic acid:acetonitrile; 25:75, v/v) at a flow rate of 0.65 mL/min on an Atlantis dC(18) column. AMG 510 and the IS eluted at similar to 0.95 and 0.73 min, respectively. AMG 510 and the IS were detected by positive electrospray ionization in multiple reaction monitoring using transition pair (Q1 -> Q3) m/z 561.1 -> 134.1 and m/z 566.5 -> 98.2, respectively. Excellent linearity was achieved in the concentration range of 1.08-5040 ng/mL (r > 0.0996). No matrix effect and carryover were observed. Intra- and inter-day accuracies and precisions were within the acceptance range. AMG 510 was demonstrated to be stable under the tested storage conditions. This novel method has been applied to a pharmacokinetic study in mice.

Automated summary

AMG 510, the first-in-class KRAS(G12C) inhibitor, is currently in phase 2 clinical trials for treating non-small cell lung cancer patients. A sensitive, selective, and high-throughput HPLC-MS/MS method was developed and validated for the quantitation of AMG 510 in mouse plasma, and successfully applied in a pharmacokinetic study in mice.