Simultaneous quantitation of IC87114, roflumilast and its active metabolite roflumilast N‐oxide in plasma by LC‐MS/MS: application for a pharmacokinetic study

Abstract

A sensitive and reliable high-performance liquid chromatography-mass spectrometry (LC-MS/MS) was developed and validated for simultaneous quantification IC87114, roflumilast (RFM), and its active metabolite roflumilast N-oxide (RFN) using tolbutamide as an internal standard. The analytes were extracted by using liquid-liquid extraction and separated on a reverse phase C(18) column (50 mm × 3 mm i.d., 4.6 µ) using methanol: 2 mM ammonium acetate buffer, pH 4.0 as mobile phase at a flow rate 1 mL/min in gradient mode. Selective reaction monitoring was performed using the transitions m/z 398.3 > 145.9, 403.1 >186.9, 419.1 > 187.0 and 271.1 > 155.0 to quantify quantification IC87114, RFM, RFN and tolbutamide, respectively. The method was validated over the concentration range of 0.1-60 ng.mL(-1) for RFM and RFN and 6 to 2980 ng.mL(-1) for IC87114. Intra- and inter-day accuracy and precision of validated method were within the acceptable limits of <15% at all concentrations. Coefficients of correlation (r(2) ) for the calibration curves were >0.99 for all analytes. The quantitation method was successfully applied for simultaneous estimation of IC87114, RFM and RFN in a pharmacokinetic drug-drug interaction study in Wistar rats.

Phosphoinositide 3-Kinase δ Regulates Dectin-2 Signaling and the Generation of Th2 and Th17 Immunity

“…Because of the short half life of the PI3Kδ inhibitor used (53), the results of PI3Kδ inhibition in vivo are likely due to proximal effects on DC-mediated sensitization which occurs over the first 24 - 72 h (54), but additional effects on the activation of T cells or B cells cannot be excluded. Several previous studies have demonstrated a role for PI3Kδ in the effector phase of antigen-induced allergic pulmonary inflammation.…”

Safety and Pharmacodynamics of the PDE4 Inhibitor Roflumilast in Advanced B-cell Malignancies

“…Quantification of roflumilast and its metabolite was performed by liquid chromatography tandem mass spectrometry (LC-MS-MS) using the analytical procedures and conditions previously described(23). In addition, in a subset of patients, 543 single nucleotide polymorphisms (SNPs) from 69 distinct genes involved in drug absorption, distribution, metabolism, and excretion (ADME) were analyzed by massively parallel sequencing.…”

Phosphodiesterase-4 inhibitors ameliorates cognitive deficits in deoxycorticosterone acetate induced hypertensive rats via cAMP/CREB signaling system

“…Plasma and brain were frozen at À80 1C until compound level determination took place. The concentrations of roflumilast and roflumilast N-oxide in plasma and brain were measured using a gradient LC/MS/MS procedure as described previously (Thappali et al, 2012). For rolipram, 200 ml plasma/brain homogenate (80:20 acetonitrile and water) were vortexed with 200 ml of acetonitrile for 60 sec.…”