Development of an UPLC-MS/MS Method for the Quantitative Analysis of Upadacitinib in Beagle Dog Plasma and Pharmacokinetics Study.

BACKGROUND: Upadacitinib, a novel selective Janus kinase 1 (JAK1) inhibitor, has been recently approved by the US FDA for the treatment of adult patients with moderately to severely active rheumatoid arthritis (RA). An ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method for the quantitative analysis of upadacitinib in beagle dog plasma was developed and validated. METHODS: Upadacitinib and fedratinib (internal standard, IS) were extracted with ethyl acetate under alkaline condition and then separated and detected. The chromatographic column was Waters Acquity UPLC BEH C18 column (2.1 mm × 50 mm, 1.7 µm), the mobile phase was acetonitrile and 0.1% formic acid in water with gradient elution procedure, and the flow rate was 0.40 mL/min. Under the positive ion mode, upadacitinib and IS were monitored by multiple reaction monitoring (MRM) as the following mass transition pairs: m/z 447.00 → 361.94 for upadacitinib and m/z 529.82 → 141.01 for IS. RESULTS: In the concentration range of 1-500 ng/mL, upadacitinib had good linearity, and the lower limit of quantification (LLOQ) was 1 ng/mL. The RSD of the intra- and inter-day precision was less than 10.03%, and the RE of accuracy was -3.79% to 2.58%. The extraction recovery of upadacitinib was more than 80%, the matrix effect was around 100%, and upadacitinib was found to be stable. CONCLUSION: The novel optimized UPLC-MS/MS assay was an effective tool for the determination of upadacitinib and had been successfully applied to the pharmacokinetic study of upadacitinib in beagle dogs, and this method would also be used to study DDIs.

Relationship between procalcitonin serum levels and functional outcome in stroke patients.

To determine whether serum procalcitonin (PCT) levels at admission were associated with short-term functional outcome after acute ischemic stroke (AIS) in a cohort Chinese sample. We prospectively studied 378 patients with AIS who were admitted within 24 h after the onset of symptoms. PCT and NIH stroke scale (NIHSS) were measured at the time of admission. Short-term functional outcome was measured by modified Rankin scale (mRS) 90 days after admission. The results indicated that the serum PCT levels were significantly higher in AIS patients as compared to normal controls (P < 0.0001). In the 114 patients with an unfavorable functional outcome, serum PCT levels were higher compared with those in patients with a favorable outcome (2.40 (IQR, 1.10-3.69) ng/mL and 0.42 (IQR, 0.10-1.05) ng/mL, respectively, P < 0.001). PCT was an independent prognostic marker of functional outcome [odds ratio (OR) 3.45 (2.29-4.77), adjusted for the NIHSS and other possible confounders] in patients with ischemic stroke, added significant additional predictive value to the clinical NIHSS score. In receiver operating characteristic curve analysis, the prognostic accuracy of PCT was higher compared to Hs-CRP and NIHSS score. PCT is an independent predictor of short-term functional outcome after ischemic stroke in Chinese sample even after correcting for possible confounding factors.