Mixed-effects modelling to quantify the effect of empagliflozin on renal glucose reabsorption in patients with type 2 diabetes.

AIMS: To quantify the effect of the sodium-glucose co-transporter 2 inhibitor, empagliflozin, on renal glucose reabsorption in patients with type 2 diabetes, and to evaluate covariate effects, using a mechanistic population pharmacokinetic-pharmacodynamic (PK-PD) model. METHODS: Four phase I/II trials were used for model development. Empagliflozin's PK characteristics were characterized by a two-compartmental model with sequential zero- and first-order absorption. Urinary glucose excretion (UGE) was described as dependent on renal glucose filtration and reabsorption; splay of the glucose reabsorption/excretion curves was considered. The modelling assumed that empagliflozin lowers the maximum renal glucose reabsorption capacity and, thereby, the renal threshold for glucose (RTg). Covariate effects were investigated using a full covariate modelling approach, emphasizing parameter estimation. RESULTS: The PK-PD model provided a reasonable description of the PK characteristics of empagliflozin and its effects on UGE across a range of renal function levels. Its parameters are consistent with reported values for renal physiology. Using this model, the effect of empagliflozin on renal glucose reabsorption was quantified. Steady-state empagliflozin doses (1, 5, 10 and 25 mg) reduced RTg from 12.5 mmol/L [95% confidence interval (CI) 12.0, 13.1] to 5.66 (95% CI 4.62, 6.72), 3.01 (95% CI 2.33, 3.69), 2.53 (95% CI 1.83, 3.14) and 2.21 (95% CI 1.47, 2.84) mg/dl, respectively. Covariate analysis showed the effect of empagliflozin on UGE was not influenced, to a clinically relevant extent, by sex, age or race. CONCLUSIONS: A method for characterizing renal glucose reabsorption was developed that does not require complex glucose clamp experiments. These analyses indicate that empagliflozin provided concentration-dependent RTg reductions, with 10 and 25 mg providing near-maximum RTg-lowering.

Bioequivalence of Linagliptin 5 mg once daily and 2.5 mg twice daily: pharmacokinetics and pharmacodynamics in an open-label crossover trial.

Linagliptin is an oral antihyperglycemic drug that acts by inhibiting the dipeptidyl peptidase-4 enzyme. A 5-mg once-daily regimen is available, but an alternative regimen was needed for twice-daily fixed-dose combinations. Although linagliptin has non-linear pharmacokinetics, simulation suggested 2.5 mg twice-daily would provide bioequivalent exposure and comparable plasma dipeptidyl peptidase-4 inhibition to 5 mg once-daily.This crossover study compared steady-state pharmacokinetics and pharmacodynamics of linagliptin 5 mg once-daily and 2.5 mg twice-daily, both administered for 7 days.In total, 16 healthy volunteers entered the study, and 15 completed both treatment periods. Exposure over 24-h at steady state (AUC0-24,ss) was similar for linagliptin 5 mg once-daily and 2.5 mg twice-daily (132 vs. 124 nmol · h/L), and the 90% confidence interval of the adjusted geometric mean ratio of AUC0-24,ss was well within the acceptance range for bioequivalence (ratio 93.9%; 90% confidence interval 89.5, 98.5). Median dipeptidyl peptidase-4 inhibition over a 24-h interval at steady state was 85.9% with linagliptin 5 mg once-daily and 86.5% with 2.5 mg twice-daily, and median dipeptidyl peptidase-4 inhibition values were approximately 80.0% at trough. Most subjects had no adverse events and there were no serious adverse events.Linagliptin 5 mg once-daily and 2.5 mg twice-daily provided bioequivalent exposure and similar inhibition of dipeptidyl peptidase-4 over the whole dosing interval.

Effect of renal impairment on the pharmacokinetics of the dipeptidyl peptidase-4 inhibitor linagliptin(*).

AIM: This study assessed the influence of various degrees of renal impairment on the exposure of linagliptin, a dipeptidyl peptidase-4 (DPP-4) inhibitor with a primarily non-renal route of excretion, in subjects with type 2 diabetes mellitus (T2DM). METHODS: Linagliptin pharmacokinetics was studied under single-dose and steady-state conditions in subjects with mild, moderate and severe renal impairment (with and without T2DM) and end-stage renal disease and compared with the pharmacokinetics in subjects with normal renal function (with and without T2DM). RESULTS: Renal excretion of unchanged linagliptin was <7% in all groups. Under single-dose conditions, the degree of renal impairment did not affect mean plasma linagliptin concentration-time profiles. These showed a similar decline and almost identical plasma concentrations 24 h postdosing in subjects with mild, moderate or severe renal impairment and in subjects with T2DM with and without renal impairment. Although there was a tendency towards slightly higher (20-60%) exposure in renally impaired subjects (with and without T2DM) compared with subjects with normal renal function, the steady-state AUC and C(max) values showed a large overlap and were not affected by the degree of renal impairment. The accumulation half-life of linagliptin ranged from 14-15 h in subjects with normal renal function to 18 h in severe renal impairment. Only a weak correlation (r(2) = 0.18) was seen between creatinine clearance and steady-state exposure. CONCLUSIONS: Renal impairment has only a minor effect on linagliptin pharmacokinetics. Consequently, there will be no need for adjusting the linagliptin dose in renally impaired patients with T2DM.