An Open-Label, Single-Period, Two-Stage, Single Oral Dose Pharmacokinetic Study of Remogliflozin Etabonate Tablet 100 and 250 mg in Healthy Asian Indian Male Subjects Under Fasting and Fed Conditions.

BACKGROUND AND OBJECTIVE: Remogliflozin etabonate is an orally available prodrug of remogliflozin, an inhibitor of renal sodium glucose co-transporter-2 (SGLT2) with antihyperglycemic activity. The present study was conducted to characterize the pharmacokinetic and safety profile of remogliflozin etabonate under fasting and fed conditions at single oral doses of 100 and 250 mg in healthy Asian Indian adults. METHODS: Sixty-five healthy, adult Asian Indian male subjects were enrolled in an open-label, two-stage, single-period pharmacokinetic study. Remogliflozin was given under fasting and/or fed conditions as a single oral dose of 100 or 250 mg. The plasma concentrations of remogliflozin etabonate, remogliflozin, and the metabolite GSK279782 were quantified by validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) method. Pharmacokinetic parameters were determined from the plasma concentration-time profile by non-compartmental analysis. Safety was assessed through monitoring of adverse events. Descriptive statistics were calculated and reported for all parameters. RESULTS: The plasma concentration profiles showed rapid absorption of the prodrug remogliflozin etabonate and rapid conversion to the active moiety, remogliflozin, which is then further metabolized to another active metabolite, GSK279782. The geometric mean maximum concentration (Cmax) and area under the plasma concentration-time curve (AUC) were comparable for all three analytes between the fasted and fed state. The fed/fasted ratio for Cmax ranged from 0.77 to 1.44 at the 100 mg dose, and from 0.80 to 1.12 at the 250 mg dose. The fed/fasted ratio for AUC was 1.22 and 1.35 at 100 and 250 mg, respectively. An early time to Cmax (tmax) was observed for all three analytes while being administered in the fasted state. Both the Cmax and AUClast of all the three analytes increased in a dose-proportional manner under the fasted and fed states. The terminal half-life for remogliflozin ranged from 1.53 to 2.07 h. All three analytes had comparable terminal half-lives irrespective of dose levels or dietary conditions. CONCLUSIONS: Following single oral administration at 100 and 250 mg, remogliflozin etabonate showed favorable, linear pharmacokinetics. There were no clinically relevant food effects on the pharmacokinetics at both the 100 and 250 mg dose levels. Remogliflozin etabonate was well-tolerated without any safety concerns or hypoglycemic events. CLINICAL TRIAL REGISTRATION: Clinical Trial Registry-India identifier number CTRI/2017/10/010043.

Validation and Analysis of Numerical Results for a Two-Pass Trapezoidal Channel With Different Cooling Configurations of Trailing Edge.

High inlet temperatures in a gas turbine lead to an increase in the thermal efficiency of the gas turbine. This results in the requirement of cooling of gas turbine blades/vanes. Internal cooling of the gas turbine blade/vanes with the help of two-pass channels is one of the effective methods to reduce the metal temperatures. In particular, the trailing edge of a turbine vane is a critical area, where effective cooling is required. The trailing edge can be modeled as a trapezoidal channel. This paper describes the numerical validation of the heat transfer and pressure drop in a trapezoidal channel with and without orthogonal ribs at the bottom surface. A new concept of ribbed trailing edge has been introduced in this paper which presents a numerical study of several trailing edge cooling configurations based on the placement of ribs at different walls. The baseline geometries are two-pass trapezoidal channels with and without orthogonal ribs at the bottom surface of the channel. Ribs induce secondary flow which results in enhancement of heat transfer; therefore, for enhancement of heat transfer at the trailing edge, ribs are placed at the trailing edge surface in three different configurations: first without ribs at the bottom surface, then ribs at the trailing edge surface in-line with the ribs at the bottom surface, and finally staggered ribs. Heat transfer and pressure drop is calculated at Reynolds number equal to 9400 for all configurations. Different turbulent models are used for the validation of the numerical results. For the smooth channel low-Re k-ɛ model, realizable k-ɛ model, the RNG k-ω model, low-Re k-ω model, and SST k-ω models are compared, whereas for ribbed channel, low-Re k-ɛ model and SST k-ω models are compared. The results show that the low-Re k-ɛ model, which predicts the heat transfer in outlet pass of the smooth channels with difference of +7%, underpredicts the heat transfer by -17% in case of ribbed channel compared to experimental data. Using the same turbulence model shows that the height of ribs used in the study is not suitable for inducing secondary flow. Also, the orthogonal rib does not strengthen the secondary flow rotational momentum. The comparison between the new designs for trailing edge shows that if pressure drop is acceptable, staggered arrangement is suitable for the outlet pass heat transfer. For the trailing edge wall, the thermal performance for the ribbed trailing edge only was found about 8% better than other configurations.