Determination of vericiguat in rat plasma by UPLC-MS/MS and its application to drug interaction.

• Develop and validate a UPLC-MS/MS method for the identification of vericiguat • Astragaloside IV significantly reduces C max of vericiguat • Drug-drug interaction might happen between vericiguat and astragaloside IV • Astragaloside IV might decrease vericiguat exposure via P-glycoprotein Vericiguat (VER) is a novel soluble guanylate cyclase stimulator treating symptomatic chronic heart failure (HF), and it is a substrate of both transporters P-glycoprotein and breast cancer resistance protein (BCRP). Astragaloside IV (ASIV) is the main active ingredient in Radix Astragali (Huangqi), a traditional Chinese medicine widely used for HF treatment in China. ASIV's effect on the protein expression of P-glycoprotein and BCRP has been observed, its impact on VER metabolism remain uncertain. In the present study, male Sprague-Dawley rats were administered with 20 mg/kg ASIV and 1 mg/kg VER to study their pharmacokinetics. Blood samples were subject to liquid-liquid extraction, and riociguat was employed as the internal standard (IS). The analytical method involved a C18 column (XSelect® HSS T3 column, 2.1 × 100 mm, 2.5 μm) with a mobile phase of 0.1% formic acid and acetonitrile for gradient elution. The flow rate of the mobile phase was set at 0.2 mL/min, and 5 µL of the sample was used for analysis. The positive ion multi-response monitoring mode was utilized with a transition of m/z 427.4→109.1 for VER and m/z 423.3→109.1 for the IS. The method exhibited good linearity within the concentration range of 0.1 to 300 ng/mL (r = 0.9987), and all the validation processes were conducted in accordance with the requirements of biological analysis. The pharmacokinetic results revealed that ASIV did not significantly alter the main parameters of VER, except for C max , which decreased by 33.2% (P < 0.05). Overall, our study successfully established a selective, sensitive and repeatable ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) analysis for detecting VER in rat plasma. [ABSTRACT FROM AUTHOR]