Effect of resveratrol on dipeptidyl peptidase-4 inhibitors pharmacokinetics: An in vitro and in vivo approach.

Diabetes mellitus (DM) is a metabolic disorder with hyperglycemia being its hallmark symptom. The secondary symptom of DM is oxidative stress, which leads to the generation of free radicals. Diabetic nephropathy and neuropathy is the long-term effect of oxidative stress caused in DM, which leads to damage of kidneys and neurons respectively. Resveratrol (RES) is a phytochemical, found to be effective in the treatment of diabetic nephropathy and neuropathy. Due to its antioxidant property, it reduces the oxidative stress caused by DM. Dipeptidyl peptidase-4 (DPP-4) inhibitors are used for the treatment of type 2 DM. In vitro and in vivo data depicted that the metabolism of alogliptin (ALO), saxagliptin (SAX) and sitagliptin (SIT) were decreased in presence of RES while metabolism of teneligliptin (TEN) was not affected in presence of RES. The results show that the alteration of the pharmacokinetics of ALO, SAX and SIT was due to inhibition of CYP P450 by RES. Thus, there was a significant pharmacokinetic interaction between RES-ALO, RES-SAX and RES-SIT. Hence, a dose reduction is required when RES therapy is taken in combination with ALO, SAX and SIT as there is an increase in drug exposure, which might lead to toxicity.

Pharmacokinetic interaction study of novel combination of palbociclib and sorafenib for hepatocellular carcinoma in SD rats.

Hepatocellular carcinoma (HCC) is a fatal oncogenic disorder with few therapeutic options. Novel therapeutic strategy with combination of a selective CDK4/6 inhibitor palbociclib (PAL) with a tyrosine kinase inhibitor (TKI) sorafenib (SOR) is reported to impair tumour growth and significantly increased survival in various preclinical models of HCC. In the current work a sensitive and rapid UHPLC-QTOF-MS method was established for the concurrent quantification of PAL and SOR in rat plasma using ibrutinib as internal standard (IS). Chromatographic separation was carried out on an Agilent Poroshell EC C18 (50 mm × 3 mm, 2.7 µm) using gradient mobile phase consisting of 0.1% formic acid and acetonitrile. Flow rate of 0. 45 mL/min with a run time of 5 min was used for separation. A simple sample preparation approach of protein precipitation was used in the current study. The mass spectrometric analysis of selective ions at [M + H]+m/z 448.2455 for PAL, m/z 465.0936 for SOR and m/z 441.2034 for IS was monitored with extracted ion chromatography. The LC-MS method meets the regulatory bio-analytical guidelines, exhibited good sensitivity and linearity over the range of 1.0-2000.0 ng/mL for PAL and SOR. The pharmacokinetic parameters of PAL remained unchanged when SOR was co-administered with PAL. The study pointed out that the co-intake of PAL with SOR resulted in a slight increment of Cmax (11.21%) and AUC (7.95%) levels of SOR when co-administered with PAL when compared to individual oral intake in SD rats. The current method provides a modern rapid and sensitive tool for pharmacokinetic studies of PAL and SOR in a pre-clinical set up.

Novel Bruton tyrosine kinase inhibitor acalabrutinib quantification by validated LC-MS/MS method: An application to pharmacokinetic study in Sprague Dawley rats.

USFDA has approved a novel Bruton tyrosine kinase (BTK) inhibitor acalabrutinib (ACA) for the treatment of mantle cell lymphoma in adults. ACA is more potent and selective with fewer side effects compared to other Bruton tyrosine kinase inhibitors. In the current work a highly sensitive, selective and specific LC-MS/MS method for the estimation of acalabrutinib (ACA) in rat plasma was developed. Agilent Eclipse Plus C 8 column (50 mm × 4.6 mm, µm), with gradient elution using 10 mM ammonium formate and acetonitrile as mobile phase at a flow rate of 0.6 mL/min was used for the chromatographic separation. The ion transitions were quantified in positive mode with MRM transition of 466.1→372.3 for ACA and 236.8→194.0 for internal standard (IS). Solid phase extraction process was used as sample preparation approach. The method was validated according to USFDA bioanalytical guidelines. The method provided good linearity over the range of 0.2-199.14 ng/mL for ACA with short run time of 4 min. The method offers very high sensitivity (0.2 ng/mL) and was free from matrix interferences. The validated LC-MS/MS method was successfully applied for in vivo pharmacokinetic study in Sprague Dawley rats. The Cmax of ACA was found to be 25.56 ng/mL reaching at time of 0.5 h. The developed analytical method can also be utilized for bioequivalence studies and/or for pharmacokinetic studies in clinics.

An assessment of the impact of green tea extract on palbociclib pharmacokinetics using a validated UHPLC-QTOF-MS method.

Green tea extracts (GTE) has been reported to be a kinase inhibitor and modulator for various drug metabolizing enzymes. It may give synergetic antioncogenic effect, but with a possibility of pharmacokinetic interactions with various co-administered anticancer agents like palbociclib (PAL), a selective inhibitor of CDK-4/6 primarily metabolized by CYP3A enzyme. To explore the impact of GTE on PAL pharmacokinetics in Sprague-Dawley rats, a rapid and sensitive UHPLC-QTOF-MS method was established. Chromatographic separation was carried out on an Acquity UPLC BEH C18 (100 × 2.1 mm, 1.7 µm) column using a gradient mobile phase system consisting of 0.1% formic acid and acetonitrile. Sample preparation was based on a simple protein precipitation method. Estimation of target ions [M + H]+ at m/z 448.2455 for PAL and m/z 441.2044 for ibrutinib (IS) was performed in selective ion mode ESI-HRMS. Good sensitivity (1.0 ng/mL) and linearity over a wide concentration range of 1-2000 ng/mL was exhibited by the method. The results indicated that the administration of GTE resulted in decreased oral bioavailability of PAL in both short- and long-term conditions. However, when both conditions were compared, the variation was less for the peak concentration and area under the concentration-time curve level of PAL.

Pharmacokinetics and brain uptake study of novel AMPA receptor antagonist perampanel in SD rats using a validated UHPLC-QTOF-MS method.

Perampanel (PER) is a novel AMPA receptor antagonist for antiepileptic therapy and is prospective for the treatment of other neurological disorders. A highly sensitive and rapid UHPLC-QTOF-MS method was developed for the quantification of PER in plasma/brain homogenate of SD rat with alogliptin as an internal standard (IS). Chromatographic separation was carried out on an Acquity UPLC HSS Cyano column (100mm×2.1mm, 1.8µm) using gradient mobile phase consisting of 0.1% formic acid and acetonitrile at a flow rate of 0. 4mL/min. Sample preparation was carried out by a simple protein precipitation method. The mass spectrometric analysis of target ions at [M+H]+m/z 350.1288 for PER and m/z 340.1779 for IS was monitored with extracted ion chromatography. The developed analytical method meets the US-FDA and EMA bioanalytical guidelines and was found to be precise, accurate, selective and rugged. It exhibited good sensitivity (0.4ng/mL) and linearity over a range of 0.4-400ng/mL in both the bio-matrices. The method was successfully applied to pharmacokinetics and brain uptake study of PER after oral administration to SD rats. The study results showed PER has penetrated the blood-brain barrier, brain to plasma ratio (Kp) was found to be 0.62±0.05 and its rapidly eliminated from the brain.

A validated LC-MS/MS method for the estimation of glimepiride and pitavastatin in rat plasma: Application to drug interaction studies.

Glimepiride (GLI) is prescribed for the management of type-2 diabetes where as pitavastatin (PIT) for the treatment of diabetes associated dyslipidemia. Both the drugs are metabolized by CYP2C9 and have the potential of altering the enzyme through either inhibition or induction. In this respect, we present a simple, fast and validated bioanalytical LC-MS/MS method for the simultaneous estimation of GLI and PIT from rat plasma. Waters XTerra RP HPLC column (4.6×100mm, 5µm) with mobile phase consisting of acetonitrile and 10mM ammonium acetate (pH-6.0) in the ratio 85:15 (v/v) at a flow rate of 1mL/min was used for the chromatographic separation. The negative ionization mode with MRM transitions: m/z 420.17→288.13 for PIT, m/z 489.59→350.12 for GLI and m/z 380.08→316.31for celecoxib as internal standard (IS). A total run time of 3min and LLOQ was found to be 5ng/mL for both PIT and GLI. The method was applied to study the drug interaction between GLI and PIT in rat liver microsomes. In vivo rat pharmacokinetics study showed there was a 1.29-fold increase in AUC0-∞ and 1.2-fold decrease in the clearance of PIT in presence of GLI. No notable difference in the pharmacokinetic profile of GLI was observed upon the intravenous co-administration of PIT.