Safety, tolerability, pharmacokinetics and pharmacokinetic-pharmacodynamic modeling of cetagliptin in patients with type 2 diabetes mellitus

Aims

To evaluate the safety, tolerability, pharmacokinetics (PK), and pharmacodynamics (PD) of cetagliptin (CAS number:2243737-33-7) in Chinese patients with type 2 diabetes mellitus (T2DM). A population PK/PD model was developed to quantify the PK and PD characteristics of cetagliptin in patients.

Materials and methods

32 Chinese adults with T2DM were enrolled in this study. The subjects were randomly assigned to receive either cetagliptin (50 mg or 100 mg), placebo, or sitagliptin (100 mg) once daily for 14 days. Blood samples were collected for PK and PD analysis. Effects on glucose, insulin, C-peptide, and glucagon were evaluated following an oral glucose tolerance test (OGTT) (day15). Effects on HbA1c and glycated albumin (GA), and safety assessments were also conducted. Meanwhile, a population PK/PD model was developed by a sequential two-step analysis approach using Phoenix.

Results

Following multiple oral doses, cetagliptin was rapidly absorbed and the mean half-life were 34.9-41.9 h. Steady-state conditions were achieved after 1 week of daily dosing and the accumulation was modest. The intensity and duration of DPP-4 inhibition induced by 50 mg cetagliptin were comparable with those induced by sitagliptin, and 100 mg cetagliptin showed a much longer sustained DPP-4 inhibition (≥80%) than sitagliptin. Compared with placebo group, plasma active GLP-1 AUEC0-24h increased by 2.20- and 3.36-fold in the 50 mg and 100 mg cetagliptin groups. A decrease of plasma glucose and increase of insulin and C-peptide were observed following OGTT in cetagliptin groups. Meanwhile, a tendency of reduced GA was observed, whereas no decreasing trend was observed in HbA1c. All adverse events related to cetagliptin and sitagliptin were assessed as mild. A population PK/PD model was successfully established. The two-compartment model and Sigmoid-Emax model could fit the observed data well. Total bilirubin (TBIL) was a covariate of volume of peripheral compartment distribution (V2), and V2 increased with the increase of TBIL.

Conclusions

Cetagliptin was well tolerated, inhibited plasma DPP-4 activity, increased plasma active GLP-1 levels, and exhibited a certain trend of glucose-lowering effect in patients with T2DM. The established population PK/PD model adequately described the PK and PD characteristics of cetagliptin.

A randomized, double-blind, placebo controlled, phase 3 trial to evaluate the efficacy and safety of cetagliptin added to ongoing metformin therapy in patients with uncontrolled type 2 diabetes with metformin monotherapy

AIM

This trial was designed to assess the efficacy and safety of cetagliptin added to metformin in Chinese patients with type 2 diabetes who had inadequate glycaemic control with metformin monotherapy.

METHODS

In total, 446 patients with type 2 diabetes on metformin monotherapy were randomized to receive the addition of once-daily cetagliptin 100 mg, cetagliptin 50 mg and placebo in a 2:2:1 ratio for 24-week double-blind treatment. At week 24, patients initially randomized to cetagliptin 50 mg and placebo were switched to cetagliptin 100 mg for 28 weeks open-label treatment. The primary endpoint was the change in haemoglobin A1c (HbA1c) from baseline, and the efficacy analyses were based on an all-patients-treated population using an analysis of co-variance.

RESULTS

After 24 weeks, both add-on therapies led to greater glycaemic control. Reductions in HbA1c from baseline were -1.17 ± 0.794%, -1.23 ± 0.896% in cetagliptin 100 mg and 50 mg plus metformin group, respectively. No difference was observed between the cetagliptin 100 mg and 50 mg plus metformin group. Patients with higher baseline HbA1c levels (≥8.5%) experienced greater reductions in HbA1c. A significantly greater proportion of patients achieved an HbA1c <7.0% with cetagliptin 100 mg (49.4%) and cetagliptin 50 mg (51.1%) plus metformin than metformin monotherapy (14.4%). Both combination therapies also improved the homeostasis model assessment β-function index and decreased systolic blood pressure. There was no increased risk of adverse effects with combination therapy, and both combination therapies were generally well tolerated.

CONCLUSIONS

The addition of cetagliptin once daily to metformin was more efficacious and well tolerated than metformin monotherapy in Chinese patients with type 2 diabetes who had inadequate glycaemic control with metformin monotherapy.

Efficacy and safety of cetagliptin as monotherapy in patients with type 2 diabetes: A randomized, double-blind, placebo-controlled phase 3 trial

AIM

To assess the efficacy and safety of the dipeptidyl peptidase-4 inhibitor, cetagliptin, as monotherapy in Chinese patients with type 2 diabetes (T2D) and inadequate glycaemic control.

MATERIALS AND METHODS

In total, 504 eligible patients with T2D were enrolled and randomized to cetagliptin 50 mg once daily, cetagliptin 100 mg once daily or placebo at a ratio of 2:2:1 for 24 weeks of double-blind treatment, then all patients received cetagliptin 100 mg once daily for 28 weeks of open-label treatment. The primary efficacy endpoint was the change in HbA1c level from baseline at week 24.

RESULTS

After 24 weeks, HbA1c from baseline was significantly reduced with cetagliptin 50 mg (-1.08%) and cetagliptin 100 mg (-1.07%) compared with placebo (-0.35%). The placebo-subtracted HbA1c reduction was -0.72% with cetagliptin 50 mg and 100 mg. Patients with a baseline HbA1c of 8.5% or higher had a greater HbA1c reduction with cetagliptin than those patients with a baseline HbA1c of less than 8.5%. Both doses studied led to a significantly higher proportion of patients (42.3% with 100 mg and 45.0% with 50 mg) achieving an HbA1c of less than 7.0% compared with placebo (12.9%). Cetagliptin also significantly lowered fasting plasma glucose and 2-hour postmeal plasma glucose relative to placebo. The incidence of adverse experiences was similar between cetagliptin and placebo. No drug-related hypoglycaemia was reported.

CONCLUSIONS

Cetagliptin monotherapy was effective and well tolerated in Chinese patients with T2D who had inadequate glycaemic control on exercise and diet.

A Double-Blind, Randomized, Placebo and Positive-Controlled Study in Healthy Volunteers to Evaluate Pharmacokinetic and Pharmacodynamic Properties of Multiple Oral Doses of Cetagliptin

AIMS

This study investigated the pharmacokinetics and pharmacodynamics properties, safety and tolerability of cetagliptin.

METHODS

Forty-eight healthy subjects were enrolled in this study. Three cohorts were investigated in sequential order: 50, 100 and 200 mg cetagliptin. Positive control (sitagliptin 100mg) was designed as open label. Blood samples were collected and analyzed for pharmacokinetics and pharmacodynamics properties. Safety and tolerability were assessed throughout the study.

RESULTS

Following multiple oral doses, cetagliptin was rapidly absorbed and reached peak plasma concentrations after approximately 1.0-1.5 h. Plasma cetagliptin concentrations increased at a rate greater than dose. Accumulation of cetagliptin was modest, and steady state was generally achieved at day 5. Doses ≥ 50 mg of cetagliptin administered once daily will result in sustained DPP-4 inhibition (≥ 80%). The EC₅₀ of DPP-4 inhibition for cetagliptin (5.29 ng/mL) was lower than that of sitagliptin (7.03 ng/mL). Active GLP-1 concentrations were significantly increased in the cetagliptin groups by 2.3 to 3.1fold at day 1 and 3.1 to 3.6 fold at steady state compared with that of placebo, and active GLP-1 concentrations were increased with increasing dose. Compared with sitagliptin, doses ≥ 100 mg QD of cetagliptin produced postprandial increases in active GLP-1 level and induced to long-lasting glucose-lowering efficacy. Across all doses of cetagliptin studied, cetagliptin was well tolerated.

CONCLUSION

Cetagliptin demonstrates the great potential for treatment with type 2 diabetes patients based on the inhibition of DPP-4, the increase in GLP-1 and insulin, the decrease in glucose, and might more effective in DPP-4 inhibition than sitagliptin.

The Metabolism and Excretion of the Dipeptidyl Peptidase 4 Inhibitor [14C] Cetagliptin in Healthy Volunteers

1. The metabolism and excretion of cetagliptin were investigated in healthy male subjects after a single oral dose of 100mg/50μCi [¹⁴C] cetagliptin.2. The mean concentration-time profile of cetagliptin was similar to that of total radioactivity in plasma after oral administration of [¹⁴C] cetagliptin in healthy male subjects. Cetagliptin was rapidly absorbed after oral administration. Unchanged cetagliptin was the most abundant radioactive component in all matrices investigated. Approximately 53.13% of plasma AUC of total radioactivity was accounted for by cetagliptin. Each metabolite plasma AUC was not higher than 2.93% of plasma AUC of total radioactivity. By 336 h after administration, 91.68% of the administered radioactivity was excreted, and the cumulative excretion in the urine and feces was 72.88% and 18.81%, respectively. The primary route of excretion of radioactivity was via the kidneys.3. Four metabolites were detected at trace levels, and it involved hydroxylated (M436-1 and M436-3), N- sulfate (M500), and N-carbamoyl glucuronic acid conjugates (M640B) of cetagliptin. These metabolites were detected also in plasma, urine, and feces at low levels, except that metabolite M640B was not detected in feces. All metabolites were observed with < 10% of parent compound systemic exposure after oral administration.

Development and validation of an ultrasensitive LC-MS/MS method for the quantification of cetagliptin in human plasma and its application in a microdose clinical trial

This study established and validated an LC-MS/MS method for the ultrasensitive determination of cetagliptin in human plasma. Sample pretreatment was achieved by liquid-liquid extraction with ethyl acetate, and chromatographic separation was performed on an XB-C₁₈ analytical column (50 × 2.1 mm, 5 μm) with gradient elution (0.1% formic acid in acetonitrile and 0.1% formic acid) at a flow rate of 1.0 mL/min. For mass spectrometric detection, multiple reaction monitoring was used, and the ion transitions monitored were m/z 421.2-86.0 for cetagliptin and m/z 424.2-88.0 for cetagliptin-d3. Method validation was performed according to the U.S. Food and Drug Administration Bioanalytical Method Validation Guidance, for which the calibration curve was linear in the range of 50.0-2000 pg/mL. All of the other results, such as selectivity, lower limit of quantitation, precision, accuracy, matrix effect, recovery, and stability, met the acceptance criteria. The validated method was successfully applied in a microdose clinical trial to systematically investigate the pharmacokinetic profile of cetagliptin in healthy subjects. Both rapid absorption and prolonged duration demonstrate the potential value of cetagliptin for diabetes treatment.