Development and validation of an HPLC-MS/MS method for the quantification of Aficamten in human plasma and urine and
Xiaofei Wu1, Aijing Liu1, Adrienne Griffith2
1Clinical Pharmacology Research Center, Beijing Key Laboratory of Key Technologies for Early Clinical Trial Evaluation of Innovative Drugs for Major Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, No. 1 Shuaifuyuan, Dongcheng District, Beijing 100730, China.
Abstract:
Aficamten (CK-3773274) is a next-in-class selective cardiac myosin inhibitor now approved for use for chronic oral therapy in hypertrophic cardiomyopathy (HCM). The present study established an innovative, rapid, and highly sensitive HPLC-MS/MS approach for quantifying aficamten concentrations in human plasma and urine. Samples were prepared using protein precipitation with acetonitrile containing CK-3942912 (D5-labelled aficamten) as the internal standard (IS). Sample separation was achieved using a C18 analytical column, with a mobile phase comprising acetonitrile and ammonium acetate. A Xevo TQS tandem mass spectrometer performed the detection in electrospray ionization (ESI) positive mode. The following MRM ion transitions were monitored: m/z 338.2 → 213.2 for CK-3773274 and m/z 343.2 → 218.2 for IS. This method was validated with excellent selectivity and sensitivity. Linear calibration curves (1-500 ng/mL) demonstrated excellent accuracy (RE% ±15%) and precision (RSD% ≤15%) for both intra- and inter-run analyses. Furthermore, critical validation parameters including matrix effects, extraction recovery, carryover, and stability were also assessed. The validated method was subsequently utilized to quantify aficamten concentrations in a clinical pharmacokinetic study involving healthy Chinese adults.
