Clinical Pharmacology for Jentadueto XR
Mechanism Of Action
JENTADUETO
JENTADUETO contains: linagliptin, a dipeptidyl peptidase-4 (DPP-4) inhibitor, and metformin, a biguanide.
Linagliptin
Linagliptin is an inhibitor of DPP-4, an enzyme that degrades the incretin hormones glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP). Thus, linagliptin increases the concentrations of active incretin hormones, stimulating the release of insulin in a glucose-dependent manner and decreasing the levels of glucagon in the circulation. Both incretin hormones are involved in the physiological regulation of glucose homeostasis. Incretin hormones are secreted at a low basal level throughout the day and levels rise immediately after meal intake. GLP-1 and GIP increase insulin biosynthesis and secretion from pancreatic beta cells in the presence of normal and elevated blood glucose levels. Furthermore, GLP-1 also reduces glucagon secretion from pancreatic alpha cells, resulting in a reduction in hepatic glucose output.
Metformin HCl
Metformin is an antihyperglycemic agent which improves glucose tolerance in patients with type 2 diabetes mellitus, lowering both basal and postprandial plasma glucose. Metformin decreases hepatic glucose production, decreases intestinal absorption of glucose, and improves insulin sensitivity by increasing peripheral glucose uptake and utilization. With metformin therapy, insulin secretion remains unchanged while fasting insulin levels and day-long plasma insulin response may decrease.
Pharmacodynamics
Linagliptin
Linagliptin binds to DPP-4 in a reversible manner and increases the concentrations of incretin hormones. Linagliptin glucose-dependently increases insulin secretion and lowers glucagon secretion, thus resulting in a better regulation of the glucose homeostasis. Linagliptin binds selectively to DPP-4 and selectively inhibits DPP-4, but not DPP-8 or DPP-9 activity in vitro at concentrations approximating therapeutic exposures.
Cardiac Electrophysiology
In a randomized, placebo-controlled, active-comparator, 4-way crossover study, 36 healthy subjects were administered a single oral dose of linagliptin 5 mg, linagliptin 100 mg (20 times the recommended dose), moxifloxacin, and placebo. No increase in QTc was observed with either the recommended dose of 5 mg or the 100 mg dose. At the 100 mg dose, peak linagliptin plasma concentrations were approximately 38-fold higher than the peak concentrations following a 5 mg dose.
Pharmacokinetics
JENTADUETO
Administration of linagliptin 2.5 mg/metformin HCl 1,000 mg fixed-dose combination with food resulted in no change in overall exposure of linagliptin. There was no change in metformin AUC; however, mean peak serum concentration of metformin was decreased by 18% when administered with food. A delayed time-to-peak serum concentrations by 2 hours was observed for metformin under fed conditions. These changes are not likely to be clinically significant.
Absorption
Linagliptin
The absolute bioavailability of linagliptin is approximately 30%. Following oral administration, plasma concentrations of linagliptin decline in at least a biphasic manner with a long terminal half-life (>100 hours), related to the saturable binding of linagliptin to DPP-4. However, the prolonged elimination does not contribute to the accumulation of the drug. The effective half-life for accumulation of linagliptin, as determined from oral administration of multiple doses of linagliptin 5 mg, is approximately 12 hours. After once-daily dosing, steady-state plasma concentrations of linagliptin 5 mg are reached by the third dose, and Cmax and AUC increased by a factor of 1.3 at steady-state compared with the first dose. Plasma AUC of linagliptin increased in a less than dose-proportional manner in the dose range of 1 to 10 mg. The pharmacokinetics of linagliptin is similar in healthy subjects and in patients with type 2 diabetes mellitus.
Metformin HCl
The absolute bioavailability of a metformin HCl 500 mg tablet given under fasting conditions is approximately 50% to 60%. Studies using single oral doses of metformin tablets 500 mg to 1,500 mg, and 850 mg to 2,550 mg, indicate that there is a lack of dose proportionality with increasing doses, which is due to decreased absorption rather than an alteration in elimination.
Distribution
Linagliptin
The mean apparent volume of distribution at steady-state following a single intravenous dose of linagliptin 5 mg to healthy subjects is approximately 1,110 L, indicating that linagliptin extensively distributes to the tissues. Plasma protein binding of linagliptin is concentration-dependent decreasing from about 99% at 1 nmol/L to 75% to 89% at ≥30 nmol/L, reflecting saturation of binding to DPP-4 with increasing concentration of linagliptin. At high concentrations, where DPP-4 is fully saturated, 70% to 80% of linagliptin remains bound to plasma proteins and 20% to 30% is unbound in plasma. Plasma binding is not altered in patients with renal or hepatic impairment.
Metformin HCl
The apparent volume of distribution (V/F) of metformin following single oral doses of immediate-release metformin HCl tablets 850 mg averaged 654±358 L. Metformin is negligibly bound to plasma proteins. Metformin partitions into erythrocytes, most likely as a function of time.
Elimination
Linagliptin
Linagliptin has a terminal half-life of about 200 hours at steady-state, though the accumulation half-life is about 11 hours. Renal clearance at steady-state was approximately 70 mL/min.
Metformin HCl
Metformin has a plasma elimination half-life of approximately 6.2 hours. In blood, the elimination half-life is approximately 17.6 hours, suggesting that the erythrocyte mass may be a compartment of distribution.
Metabolism
Linagliptin
Following oral administration, the majority (about 90%) of linagliptin is excreted unchanged, indicating that metabolism represents a minor elimination pathway. A small fraction of absorbed linagliptin is metabolized to a pharmacologically inactive metabolite, which shows a steady-state exposure of 13.3% relative to linagliptin.
Metformin HCl
Intravenous single-dose studies in normal subjects demonstrate that metformin does not undergo hepatic metabolism (no metabolites have been identified in humans), nor biliary excretion.
Excretion
Linagliptin
Following administration of an oral [14C] linagliptin dose to healthy subjects, approximately 85% of the administered radioactivity was eliminated via the enterohepatic system (80%) or urine (5%) within 4 days of dosing.
Metformin HCl
Following oral administration, approximately 90% of the absorbed drug is excreted via the renal route within the first 24 hours. Renal clearance is approximately 3.5 times greater than creatinine clearance, which indicates that tubular secretion is the major route of metformin elimination.
Specific Populations
Renal Impairment
JENTADUETO
Studies characterizing the pharmacokinetics of linagliptin and metformin after administration of JENTADUETO in renally impaired patients have not been performed.
Linagliptin
Under steady-state conditions, linagliptin exposure in patients with mild renal impairment was comparable to healthy subjects. In patients with moderate renal impairment under steady-state conditions, mean exposure of linagliptin increased (AUCτ,ss by 71% and Cmax by 46%) compared with healthy subjects. This increase was not associated with a prolonged accumulation half-life, terminal half-life, or an increased accumulation factor. Renal excretion of linagliptin was below 5% of the administered dose and was not affected by decreased renal function.
Patients with type 2 diabetes mellitus and severe renal impairment showed steady-state exposure approximately 40% higher than that of patients with type 2 diabetes mellitus and normal renal function (increase in AUC by 42% and Cmax by 35%). For both type 2 diabetes mellitus groups, renal excretion was below 7% of the administered dose.
These findings were further supported by the results of population pharmacokinetic analyses.
Metformin HCl
In patients with decreased renal function, the plasma and blood half-life of metformin is prolonged and the renal clearance is decreased [see CONTRAINDICATIONS and WARNINGS AND PRECAUTIONS].
Hepatic Impairment
JENTADUETO
Studies characterizing the pharmacokinetics of linagliptin and metformin after administration of JENTADUETO in hepatically impaired patients have not been performed [see WARNINGS AND PRECAUTIONS].
Linagliptin
In patients with mild hepatic impairment (Child-Pugh class A) steady-state exposure (AUCτ,ss) of linagliptin was approximately 25% lower and Cmax,ss was approximately 36% lower than in healthy subjects. In patients with moderate hepatic impairment (Child-Pugh class B), AUCss of linagliptin was about 14% lower and Cmax,ss was approximately 8% lower than in healthy subjects. Patients with severe hepatic impairment (Child-Pugh class C) had comparable exposure of linagliptin in terms of AUC0-24 and approximately 23% lower Cmax compared with healthy subjects. Reductions in the pharmacokinetic parameters seen in patients with hepatic impairment did not result in reductions in DPP-4 inhibition.
Metformin HCl
No pharmacokinetic studies of metformin have been conducted in patients with hepatic impairment.
Effects Of Age, Body Mass Index (Bmi), Gender, And Race
Linagliptin
Based on the population pharmacokinetic analysis, age, BMI, gender, and race do not have a clinically meaningful effect on pharmacokinetics of linagliptin [see Use In Specific Populations].
Metformin HCl
Metformin pharmacokinetic parameters did not differ significantly between normal subjects and patients with type 2 diabetes mellitus when analyzed according to gender. Similarly, in controlled clinical studies in patients with type 2 diabetes mellitus, the antihyperglycemic effect of metformin was comparable in males and females.
Limited data from controlled pharmacokinetic studies of metformin in healthy elderly subjects suggest that total plasma clearance of metformin is decreased, the halflife is prolonged, and Cmax is increased, compared with healthy young subjects. From these data, it appears that the change in metformin pharmacokinetics with aging is primarily accounted for by a change in renal function.
No studies of metformin pharmacokinetic parameters according to race have been performed. In controlled clinical studies of metformin HCl in patients with type 2 diabetes mellitus, the antihyperglycemic effect was comparable in Caucasians (n=249), Blacks (n=51), and Hispanics (n=24).
Drug Interactions
Pharmacokinetic drug interaction studies with JENTADUETO have not been performed; however, such studies have been conducted with the individual components of JENTADUETO (linagliptin and metformin HCl).
Linagliptin
In vitro Assessment of Drug Interactions
Linagliptin is a weak to moderate inhibitor of CYP isozyme CYP3A4, but does not inhibit other CYP isozymes and is not an inducer of CYP isozymes, including CYP1A2, 2A6, 2B6, 2C8, 2C9, 2C19, 2D6, 2E1, and 4A11.
Linagliptin is a P-glycoprotein (P-gp) substrate, and inhibits P-gp mediated transport of digoxin at high concentrations. Based on these results and in vivo drug interaction studies, linagliptin is considered unlikely to cause interactions with other P-gp substrates at therapeutic concentrations.
In vivo Assessment of Drug Interactions
Strong inducers of CYP3A4 or P-gp (e.g., rifampin) decrease exposure to linagliptin to subtherapeutic and likely ineffective concentrations [see DRUG INTERACTIONS].
In vivo studies indicated evidence of a low propensity for causing drug interactions with substrates of CYP3A4, CYP2C9, CYP2C8, P-gp, and organic cationic transporter (OCT).
Table 3 describes the effect of coadministered drugs on systemic exposure of linagliptin.
Table 3: Effect of Coadministered Drugs on Systemic Exposure of Linagliptin
| Coadministered Drug |
Dosing of Coadministered Drug* |
Dosing of Linagliptin* |
Geometric Mean Ratio
(ratio with/without coadministered drug)
No effect=1.0 |
| AUC† |
Cmax |
| Metformin |
850 mg TID |
10 mg QD |
1.20 |
1.03 |
| Glyburide |
1.75 mg# |
5 mg QD |
1.02 |
1.01 |
| Pioglitazone |
45 mg QD |
10 mg QD |
1.13 |
1.07 |
| Ritonavir |
200 mg BID |
5 mg# |
2.01 |
2.96 |
| Rifampin** |
600 mg QD |
5 mg QD |
0.60 |
0.56 |
*Multiple dose (steady-state) unless otherwise noted
**For information regarding clinical recommendations [see DRUG INTERACTIONS].
#Single dose
†AUC = AUC(0 to 24 hours) for single-dose treatments and AUC = AUC(TAU) for multiple-dose treatments
QD=once daily
BID=twice daily
TID=three times daily |
Table 4 describes the effect of linagliptin on systemic exposure of coadministered drugs.
Table 4: Effect of Linagliptin on Systemic Exposure of Coadministered Drugs
| Coadministered Drug |
Dosing of Coadministered Drug* |
Dosing of Linagliptin* |
Geometric Mean Ratio
(ratio with/without coadministered drug)
No effect=1.0 |
|
AUC† |
Cmax |
| Metformin |
850 mg TID |
10 mg QD |
metformin |
1.01 |
0.89 |
| Glyburide |
1.75 mg# |
5 mg QD |
glyburide |
0.86 |
0.86 |
| Pioglitazone |
45 mg QD |
10 mg QD |
pioglitazone |
0.94 |
0.86 |
|
|
|
metabolite M-III |
0.98 |
0.96 |
|
|
|
metabolite M-IV |
1.04 |
1.05 |
| Digoxin |
0.25 mg QD |
5 mg QD |
digoxin |
1.02 |
0.94 |
| Simvastatin |
40 mg QD |
10 mg QD |
simvastatin |
1.34 |
1.10 |
|
|
|
simvastatin acid |
1.33 |
1.21 |
| Warfarin |
10 mg# |
5 mg QD |
R-warfarin |
0.99 |
1.00 |
|
|
|
S-warfarin |
1.03 |
1.01 |
|
|
|
INR |
0.93** |
1.04** |
|
|
|
PT |
1.03** |
1.15** |
Ethinylestradiol and
levonorgestrel |
ethinylestradiol 0.03 mg and
levonorgestrel 0.150 mg QD |
5 mg QD |
ethinylestradiol |
1.01 |
1.08 |
|
|
|
levonorgestrel |
1.09 |
1.13 |
*Multiple dose (steady-state) unless otherwise noted
#Single dose
†AUC = AUC(INF) for single-dose treatments and AUC = AUC(TAU) for multiple-dose treatments
**AUC=AUC(0-168) and Cmax=Emax for pharmacodynamic end points
INR=International Normalized Ratio
PT=Prothrombin Time
QD=once daily
TID=three times daily |
Metformin HCl
Table 5 describes the effect of coadministered drugs on plasma metformin systemic exposure.
Table 5: Effect of Coadministered Drugs on Plasma Metformin Systemic Exposure
| Coadministered Drug |
Dosing of Coadministered Drug* |
Dosing of Metformin* |
Geometric Mean Ratio
(ratio with/without coadministered drug)
No effect=1.0 |
|
AUC† |
Cmax |
| Glyburide |
5 mg |
850 mg |
metformin |
0.91‡ |
0.93‡ |
| Furosemide |
40 mg |
850 mg |
metformin |
1.09‡ |
1.22‡ |
| Nifedipine |
10 mg |
850 mg |
metformin |
1.16 |
1.21 |
| Propranolol |
40 mg |
850 mg |
metformin |
0.90 |
0.94 |
| Ibuprofen |
400 mg |
850 mg |
metformin |
1.05‡ |
1.07‡ |
| Cationic drugs eliminated by renal tubular secretion may reduce metformin elimination [see DRUG INTERACTIONS]. |
| Cimetidine |
400 mg |
850 mg |
metformin |
1.40 |
1.61 |
| Carbonic anhydrase inhibitors may cause metabolic acidosis [see DRUG INTERACTIONS]. |
| Topiramate** |
100 mg |
500 mg |
metformin |
1.25 |
1.17 |
*All metformin and coadministered drugs were given as single doses
†AUC=AUC(INF)
‡Ratio of arithmetic means
**At steady-state with topiramate 100 mg every 12 hours and metformin 500 mg every 12 hours; AUC = AUC(0-12 hours) |
Table 6 describes the effect of metformin on coadministered drug systemic exposure.
Table 6: Effect of Metformin on Coadministered Drug Systemic Exposure
| Coadministered Drug |
Dosing of Coadministered Drug* |
Dosing of Metformin* |
Geometric Mean Ratio
(ratio with/without metformin)
No effect=1.0 |
|
AUC† |
Cmax |
| Glyburide |
5 mg |
850 mg |
glyburide |
0.78‡ |
0.63‡ |
| Furosemide |
40 mg |
850 mg |
furosemide |
0.87‡ |
0.69‡ |
| Nifedipine |
10 mg |
850 mg |
nifedipine |
1.10§ |
1.08 |
| Propranolol |
40 mg |
850 mg |
propranolol |
1.01§ |
1.02 |
| Ibuprofen |
400 mg |
850 mg |
ibuprofen |
0.97¶ |
1.01¶ |
| Cimetidine |
400 mg |
850 mg |
cimetidine |
0.95§ |
1.01 |
*All metformin and coadministered drugs were given as single doses
†AUC=AUC(INF) unless otherwise noted
‡Ratio of arithmetic means, p-value of difference <0.05
§AUC(0-24 hours) reported
¶Ratio of arithmetic means |
Clinical Studies
Glycemic Control Trials In Adults With Type 2 Diabetes Mellitus
Initial Combination Therapy With Linagliptin And Metformin
A total of 791 patients with type 2 diabetes mellitus and inadequate glycemic control on diet and exercise participated in the 24-week, randomized, double-blind, portion of this placebo-controlled factorial trial designed to assess the efficacy of linagliptin as initial therapy with metformin. Patients on an antihyperglycemic agent (52%) underwent a drug washout period of 4 weeks’ duration. After the washout period and after completing a 2-week single-blind placebo run-in period, patients with inadequate glycemic control (A1C ≥7.0% to ≤10.5%) were randomized. Patients with inadequate glycemic control (A1C ≥7.5% to <11.0%) not on antihyperglycemic agents at trial entry (48%) immediately entered the 2-week single-blind placebo run-in period and then were randomized. Randomization was stratified by baseline A1C (<8.5% vs ≥8.5%) and use of a prior oral antidiabetic drug (none vs monotherapy). Patients were randomized in a 1:2:2:2:2:2 ratio to either placebo or one of 5 activetreatment arms. Approximately equal numbers of patients were randomized to receive initial therapy with 5 mg of linagliptin once daily, 500 mg or 1,000 mg of metformin twice daily, or 2.5 mg of linagliptin twice daily in combination with 500 mg or 1,000 mg of metformin twice daily. Patients who failed to meet specific glycemic goals during the trial were treated with sulfonylurea, thiazolidinedione, or insulin rescue therapy.
Initial therapy with the combination of linagliptin and metformin provided significant improvements in A1C, and fasting plasma glucose (FPG) compared to placebo, to metformin alone, and to linagliptin alone (Table 7, Figure 1). The adjusted mean treatment difference in A1C from baseline to week 24 (LOCF) was -0.5% (95% CI -0.7, -0.3; p<0.0001) for linagliptin 2.5 mg/metformin 1,000 mg twice daily compared to metformin 1,000 mg twice daily; -1.1% (95% CI -1.4, -0.9; p<0.0001) for linagliptin 2.5 mg/metformin 1,000 mg twice daily compared to linagliptin 5 mg once daily; -0.6% (95% CI -0.8, -0.4; p<0.0001) for linagliptin 2.5 mg/metformin 500 mg twice daily compared to metformin 500 mg twice daily; and -0.8% (95% CI -1.0, -0.6; p<0.0001) for linagliptin 2.5 mg/metformin 500 mg twice daily compared to linagliptin 5 mg once daily.
Lipid effects were generally neutral. No meaningful change in body weight was noted in any of the 6 treatment groups.
Table 7 Glycemic Parameters at Final Visit (24-Week Trial) for Linagliptin and Metformin, Alone and in Combination in Randomized Patients with Type 2 Diabetes Mellitus Inadequately Controlled on Diet and Exercise**
|
Placebo |
Linagliptin 5 mg
Once Daily* |
Metformin 500 mg
Twice Daily |
Linagliptin 2.5 mg
Twice Daily* +
Metformin 500 mg
Twice Daily |
Metformin
1,000 mg
Twice Daily |
Linagliptin 2.5 mg
Twice Daily* +
Metformin 1,000 mg
Twice Daily |
| A1C (%) |
|
|
|
|
|
|
| Number of patients |
n=65 |
n=135 |
n=141 |
n=137 |
n=138 |
n=140 |
| Baseline (mean) |
8.7 |
8.7 |
8.7 |
8.7 |
8.7 |
8.7 |
Change from baseline (adjusted
mean****) |
0.1 |
-0.5 |
-0.6 |
-1.2 |
-1.1 |
-1.6 |
Difference from placebo (adjusted
mean) (95% CI) |
-- |
-0.6
(-0.9, -0.3) |
-0.8
(-1.0, -0.5) |
-1.3
(-1.6, -1.1) |
-1.2
(-1.5, -0.9) |
-1.7
(-2.0, -1.4) |
Patients [n (%)] achieving A1C
<7%*** |
7 (10.8) |
14 (10.4) |
26 (18.6) |
41 (30.1) |
42 (30.7) |
74 (53.6) |
Patients (%) receiving rescue
medication |
29.2 |
11.1 |
13.5 |
7.3 |
8.0 |
4.3 |
| FPG (mg/dL) |
|
|
|
|
|
|
| Number of patients |
n=61 |
n=134 |
n=136 |
n=135 |
n=132 |
n=132 |
| Baseline (mean) |
203 |
195 |
191 |
199 |
191 |
196 |
Change from baseline (adjusted
mean****) |
10 |
-9 |
-16 |
-33 |
-32 |
-49 |
Difference from placebo (adjusted
mean) (95% CI) |
-- |
-19
(-31, -6) |
-26
(-38, -14) |
-43
(-56, -31) |
-42
(-55, -30) |
-60
(-72, -47) |
*Total daily dosage of linagliptin is equal to 5 mg
**Full analysis population using last observation on trial
***Metformin 500 mg twice daily, n=140; Linagliptin 2.5 mg twice daily + Metformin 500 mg twice daily, n=136; Metformin 1,000 mg twice daily, n=137; Linagliptin 2.5 mg twice daily + Metformin 1,000 mg twice daily, n=138
****HbA1c: ANCOVA model included treatment and number of prior OADs as class-effects, as well as baseline HbA1c as continuous covariates. FPG: ANCOVA model included treatment and number of prior OADs as class-effects, as well as baseline HbA1c and baseline FPG as continuous covariates. |
Figure 1: Adjusted Mean Change from Baseline for A1C (%) over 24 Weeks with Linagliptin and Metformin, Alone and in Combination in Patients with Type 2 Diabetes Mellitus Inadequately Controlled with Diet and Exercise - FAS completers
Initial Combination Therapy With Linagliptin And Metformin Vs Linagliptin In Treatment-Naïve Patients
A total of 316 patients with type 2 diabetes mellitus diagnosed within the previous 12 months and treatment-naïve (no antidiabetic therapy for 12 weeks prior to randomization) and inadequate glycemic control (A1C ≥8.5% to ≤12.0%) participated in a 24-week, randomized, double-blind, trial designed to assess the efficacy of linagliptin in combination with metformin vs linagliptin. Patients were randomized (1:1), after a 2-week run-in period, to either linagliptin 5 mg plus metformin (1,500 to 2,000 mg per day, n=159) or linagliptin 5 mg plus placebo, (n=157) administered once daily. Patients in the linagliptin and metformin treatment group were uptitrated to a maximum tolerated dosage of metformin (1,000 to 2,000 mg per day) over a three-week period.
Initial therapy with the combination of linagliptin and metformin provided statistically significant improvements in A1C compared to linagliptin (Table 8). The mean difference between groups in A1C change from baseline was -0.8% with 2-sided 95% confidence interval (-1.23%, -0.45%).
Table 8 Glycemic Parameters at 24 Weeks in Trial Comparing Linagliptin in Combination with Metformin to Linagliptin in Treatment-Naïve Patients*
|
Linagliptin 5 mg + Metformin |
Linagliptin 5 mg + Placebo |
| A1C (%)* |
| Number of patients |
n=153 |
n=150 |
| Baseline (mean) |
9.8 |
9.9 |
| Change from baseline (adjusted mean) |
-2.9 |
-2 |
| Difference from linagliptin (adjusted mean**) (95% CI) |
-0.84†
(-1.23, -0.45) -- |
|
| Patients [n (%)] achieving A1C <7%* |
82 (53.6) |
45 (30) |
| FPG (mg/dL)* |
| Number of patients |
n=153 |
n=150 |
| Baseline (mean) |
196 |
198 |
| Change from baseline (adjusted mean) |
-54 |
-35 |
| Difference from linagliptin (adjusted mean**) (95% CI) |
-18†† (-31, -5.5) |
-- |
†p<0.0001 compared to linagliptin, ††p=0.0054 compared to linagliptin
*Full analysis set population
**A1C: MMRM model included treatment, continuous baseline A1C, baseline A1C by visit interaction, visit by treatment interaction, baseline renal impairment by treatment interaction and baseline renal impairment by treatment by visit interaction. FPG: MMRM model included treatment, continuous baseline A1C, continuous baseline FPG, baseline FPG by visit interaction, visit by treatment interaction, baseline renal impairment by treatment interaction and baseline renal impairment by treatment by visit interaction. |
The adjusted mean changes for A1C (%) from baseline over time for linagliptin and metformin as compared to linagliptin alone were maintained throughout the 24- week treatment period. Using the completers analysis the respective adjusted means for A1C (%) changes from baseline for linagliptin and metformin as compared to linagliptin alone were -1.9 and -1.3 at week 6, -2.6 and -1.8 at week 12, -2.7 and -1.9 at week 18, and -2.7 and -1.9 at week 24. Changes in body weight from baseline were not clinically significant in either treatment group.
Add-On Combination Therapy With Metformin
A total of 701 patients with type 2 diabetes mellitus participated in a 24-week, randomized, double-blind, placebo-controlled trial designed to assess the efficacy of linagliptin in combination with metformin. Patients already on metformin (n=491) at a dosage of at least 1,500 mg per day were randomized after completing a 2-week, open-label, placebo run-in period. Patients on metformin and another antihyperglycemic agent (n=207) were randomized after a run-in period of approximately 6 weeks on metformin (at a dosage of at least 1,500 mg per day) in monotherapy. Patients were randomized to the addition of either linagliptin 5 mg or placebo, administered once daily. Patients who failed to meet specific glycemic goals during the studies were treated with glimepiride rescue.
In combination with metformin, linagliptin provided statistically significant improvements in A1C, FPG, and 2-hour PPG compared with placebo (Table 9). Rescue glycemic therapy was used in 7.8% of patients treated with linagliptin 5 mg and in 18.9% of patients treated with placebo. A similar decrease in body weight was observed for both treatment groups.
Table 9 Glycemic Parameters in Placebo-Controlled Trial for Linagliptin in Combination with Metformin*
|
Linagliptin 5 mg + Metformin |
Placebo + Metformin |
| A1C (%) |
| Number of patients |
n=513 |
n=175 |
| Baseline (mean) |
8.1 |
8.0 |
| Change from baseline (adjusted mean***) |
-0.5 |
0.15 |
| Difference from placebo + metformin (adjusted mean) (95% CI) |
-0.6 (-0.8, -0.5) |
-- |
| Patients [n (%)] achieving A1C <7%** |
127 (26.2) |
15 (9.2) |
| FPG (mg/dL) |
| Number of patients |
n=495 |
n=159 |
| Baseline (mean) |
169 |
164 |
| Change from baseline (adjusted mean***) |
-11 |
11 |
| Difference from placebo + metformin (adjusted mean) (95% CI) |
-21 (-27, -15) |
-- |
| 2-hour PPG (mg/dL) |
|
|
| Number of patients |
n=78 |
n=21 |
| Baseline (mean) |
270 |
274 |
| Change from baseline (adjusted mean***) |
-49 |
18 |
| Difference from placebo + metformin (adjusted mean) (95% CI) |
-67 (-95, -40) |
-- |
* Full analysis population using last observation on trial
**Linagliptin 5 mg + Metformin, n=485; Placebo + Metformin, n=163
***HbA1c: ANCOVA model included treatment and number of prior oral OADs as class-effects, as well as baseline HbA1c as continuous covariates. FPG:
ANCOVA model included treatment and number of prior OADs as class-effects, as well as baseline HbA1c and baseline FPG as continuous covariates. PPG:
ANCOVA model included treatment and number of prior OADs as class-effects, as well as baseline HbA1c and baseline postprandial glucose after two hours as covariate. |
Active-Controlled Trial Vs Glimepiride In Combination With Metformin
The efficacy of linagliptin was evaluated in a 104-week, double-blind, glimepiride-controlled non-inferiority trial in type 2 diabetic patients with insufficient glycemic control despite metformin therapy. Patients being treated with metformin only entered a run-in period of 2 weeks’ duration, whereas patients pretreated with metformin and one additional antihyperglycemic agent entered a run-in treatment period of 6 weeks’ duration with metformin monotherapy (dosage of ≥1,500 mg per day) and washout of the other agent. After an additional 2-week placebo run-in period, those with inadequate glycemic control (A1C 6.5% to 10%) were randomized 1:1 to the addition of linagliptin 5 mg once daily or glimepiride. Randomization was stratified by baseline HbA1c (<8.5% vs ≥8.5%), and the previous use of antidiabetic drugs (metformin alone vs metformin plus one other OAD). Patients receiving glimepiride were given an initial dosage of 1 mg/day and then electively titrated over the next 12 weeks to a maximum dosage of 4 mg/day as needed to optimize glycemic control. Thereafter, the glimepiride dosage was to be kept constant, except for downtitration to prevent hypoglycemia.
After 52 weeks and 104 weeks, linagliptin and glimepiride both had reductions from baseline in A1C (52 weeks: -0.4% for linagliptin, -0.6% for glimepiride; 104 weeks: -0.2% for linagliptin, -0.4% for glimepiride) from a baseline mean of 7.7% (Table 10). The mean difference between groups in A1C change from baseline was 0.2% with 2-sided 97.5% confidence interval (0.1%, 0.3%) for the intent-to-treat population using last observation carried forward. These results were consistent with the completers analysis.
Table 10 Glycemic Parameters at 52 and 104 Weeks in Trial Comparing Linagliptin to Glimepiride as Add-On Therapy in Patients Inadequately Controlled on Metformin**
|
Week 52 |
Week 104 |
Linagliptin 5 mg +
Metformin |
Glimepiride + Metformin
(mean glimepiride dosage 3
mg) |
Linagliptin 5 mg +
Metformin |
Glimepiride + Metformin
(mean glimepiride dosage 3
mg) |
| A1C (%) |
| Number of patients |
n=764 |
n=755 |
n=764 |
n=755 |
| Baseline (mean) |
7.7 |
7.7 |
7.7 |
7.7 |
| Change from baseline (adjusted mean***) |
-0.4 |
-0.6 |
-0.2 |
-0.4 |
Difference from glimepiride (adjusted mean)
(97.5% CI) |
0.2 (0.1, 0.3) |
-- |
0.2 (0.1, 0.3) |
-- |
| FPG (mg/dL) |
| Number of patients |
n=733 |
n=725 |
n=733 |
n=725 |
| Baseline (mean) |
164 |
166 |
164 |
166 |
| Change from baseline (adjusted mean***) |
-8* |
-15 |
-2† |
-9 |
*p<0.0001 vs glimepiride;
†p=0.0012 vs glimepiride
**Full analysis population using last observation on trial
***HbA1c: ANCOVA model included treatment and number of prior OADs as class-effects, as well as baseline HbA1c as continuous covariates. FPG: ANCOVA model included treatment and number of prior OADs as class-effects, as well as baseline HbA1c and baseline FPG as continuous covariates. |
Patients treated with linagliptin had a mean baseline body weight of 86 kg and were observed to have an adjusted mean decrease in body weight of 1.1 kg at 52 weeks and 1.4 kg at 104 weeks. Patients on glimepiride had a mean baseline body weight of 87 kg and were observed to have an adjusted mean increase from baseline in body weight of 1.4 kg at 52 weeks and 1.3 kg at 104 weeks (treatment difference p<0.0001 for both timepoints).
Add-On Combination Therapy With Metformin And A Sulfonylurea
A total of 1,058 patients with type 2 diabetes mellitus participated in a 24-week, randomized, double-blind, placebo-controlled trial designed to assess the efficacy of linagliptin in combination with a sulfonylurea and metformin. The most common sulfonylureas used by patients in the trial were glimepiride (31%), glibenclamide (26%), and gliclazide (26% [not available in the United States]). Patients on a sulfonylurea and metformin were randomized to receive linagliptin 5 mg or placebo, each administered once daily. Patients who failed to meet specific glycemic goals during the trial were treated with pioglitazone rescue. Glycemic end points measured included A1C and FPG.
In combination with a sulfonylurea and metformin, linagliptin provided statistically significant improvements in A1C and FPG compared with placebo (Table 11). In the entire trial population (patients on linagliptin in combination with a sulfonylurea and metformin), a mean reduction from baseline relative to placebo in A1C of -0.6% and in FPG of -13 mg/dL was seen. Rescue therapy was used in 5.4% of patients treated with linagliptin 5 mg and in 13% of patients treated with placebo. Change from baseline in body weight did not differ significantly between the groups.
Table 11 Glycemic Parameters at Final Visit (24-Week Trial) for Linagliptin in Combination with Metformin and Sulfonylurea*
|
Linagliptin 5 mg + Metformin + SU |
Placebo + Metformin + SU |
| A1C (%) |
| Number of patients |
n=778 |
n=262 |
| Baseline (mean) |
8.2 |
8.1 |
| Change from baseline (adjusted mean***) |
-0.7 |
-0.1 |
| Difference from placebo (adjusted mean) (95% CI) |
-0.6 (-0.7, -0.5) |
-- |
| Patients [n (%)] achieving A1C <7%** |
217 (29.2) |
20 (8.1) |
| FPG (mg/dL) |
|
|
| Number of patients |
n=739 |
n=248 |
| Baseline (mean) |
159 |
163 |
| Change from baseline (adjusted mean***) |
-5 |
8 |
| Difference from placebo (adjusted mean) (95% CI) |
-13 (-18, -7) |
-- |
SU=sulfonylurea
*Full analysis population using last observation on trial
**Linagliptin 5 mg + Metformin + SU, n=742; Placebo + Metformin + SU, n=247
***HbA1c: ANCOVA model included treatment as class-effects and baseline HbA1c as continuous covariates. FPG: ANCOVA model included treatment as classeffects, as well as baseline HbA1c and baseline FPG as continuous covariates. |
Linagliptin Cardiovascular Safety Trials In Patients With Type 2 Diabetes Mellitus
CARMELINA
The cardiovascular risk of linagliptin was evaluated in CARMELINA, a multi-national, multi-center, placebo-controlled, double-blind, parallel group trial comparing linagliptin (N=3,494) to placebo (N=3,485) in adult patients with type 2 diabetes mellitus and a history of established macrovascular and/or renal disease. The trial compared the risk of major adverse cardiovascular events (MACE) between linagliptin and placebo when these were added to standard of care treatments for diabetes mellitus and other cardiovascular risk factors. The trial was event driven, the median duration of follow-up was 2.2 years and vital status was obtained for 99.7% of patients.
Patients were eligible to enter the trial if they were adults with type 2 diabetes mellitus, with HbA1c of 6.5% to 10%, and had either albuminuria and previous macrovascular disease (39% of enrolled population), or evidence of impaired renal function by eGFR and Urinary Albumin Creatinine Ratio (UACR) criteria (42% of enrolled population), or both (18% of enrolled population).
At baseline the mean age was 66 years and the population was 63% male, 80% White, 9% Asian, 6% Black or African American and 36% were of Hispanic or Latino ethnicity. Mean HbA1c was 8.0% and mean duration of type 2 diabetes mellitus was 15 years. The trial population included 17% patients ≥75 years of age and 62% patients with renal impairment defined as eGFR <60 mL/min/1.73 m2. The mean eGFR was 55 mL/min/1.73 m2 and 27% of patients had mild renal impairment (eGFR 60 to 90 mL/min/1.73 m2), 47% of patients had moderate renal impairment (eGFR 30 to <60 mL/min/1.73 m2) and 15% of patients had severe renal impairment (eGFR <30 mL/min/1.73 m2). Patients were taking at least one antidiabetic drug (97%), and the most common were insulin and analogues (57%), metformin (54%) and sulfonylurea (32%). Patients were also taking antihypertensives (96%), lipid lowering drugs (76%) with 72% on statin, and aspirin (62%).
The primary endpoint, MACE, was the time to first occurrence of one of three composite outcomes which included cardiovascular death, non-fatal myocardial infarction or non-fatal stroke. The trial was designed as a non-inferiority trial with a pre-specified risk margin of 1.3 for the hazard ratio of MACE.
The results of CARMELINA, including the contribution of each component to the primary composite endpoint, are shown in Table 12. The estimated hazard ratio for MACE associated with linagliptin relative to placebo was 1.02 with a 95% confidence interval of (0.89, 1.17). The upper bound of this confidence interval, 1.17, excluded the risk margin of 1.3. The Kaplan-Meier curve depicting time to first occurrence of MACE is shown in Figure 2.
Table 12: Major Adverse Cardiovascular Events (MACE) by Treatment Group in the CARMELINA Trial
|
Linagliptin 5 mg
n = 3,494 |
Placebo
n = 3,485 |
Hazard Ratio |
| Number of Subjects (%) |
Incidence Rate per 1,000 PY* |
Number of Subjects (%) |
Incidence Rate per 1,000 PY* |
(95% CI) |
| Composite of first event of CV death, nonfatal myocardial infarction (MI), or non-fatal stroke (MACE) |
434 (12.4) |
57.7 |
420 (12.1) |
56.3 |
1.02
(0.89, 1.17) |
| CV death** |
255 (7.3) |
32.6 |
264 (7.6) |
34.0 |
0.96
(0.81, 1.14) |
| Non-fatal MI** |
156 (4.5) |
20.6 |
135 (3.9) |
18.0 |
1.15
(0.91, 1.45) |
| Non-fatal stroke** |
65 (1.9) |
8.5 |
73 (2.1) |
9.6 |
0.88
(0.63, 1.23) |
*PY=patient years
**A patient may have experienced more than one component; therefore, the sum of the components is larger than the number of patients who experienced the composite outcome. |
Figure 2 Kaplan-Meier: Time to First Occurrence of MACE in the CARMELINA Trial
CAROLINA
The cardiovascular risk of linagliptin was evaluated in CAROLINA, a multi-center, multi-national, randomized, double-blind, parallel group trial comparing linagliptin (N=3,023) to glimepiride (N=3,010) in adult patients with type 2 diabetes mellitus and a history of established cardiovascular disease and/or multiple cardiovascular risk factors. The trial compared the risk of major adverse cardiovascular events (MACE) between linagliptin and glimepiride when these were added to standard of care treatments for diabetes mellitus and other cardiovascular risk factors. The trial was event driven, the median duration of follow-up was 6.23 years and vital status was obtained for 99.3% of patients.
Patients were eligible to enter the trial if they were adults with type 2 diabetes mellitus with insufficient glycemic control (defined as HbA1c of 6.5% to 8.5% or 6.5% to 7.5% depending on whether treatment-naïve, on monotherapy or on combination therapy), and were defined to be at high cardiovascular risk with previous vascular disease, evidence of vascular related end-organ damage, age ≥70 years, and/or two cardiovascular risk factors (duration of diabetes mellitus >10 years, systolic blood pressure >140 mmHg, current smoker, LDL cholesterol ≥135 mg/dL).
At baseline, the mean age was 64 years and the population was 60% male, 73% White, 18% Asian, 5% Black or African American, and 17% were of Hispanic or Latino ethnicity. The mean HbA1c was 7.15% and mean duration of type 2 diabetes mellitus was 7.6 years. The trial population included 34% patients ≥70 years of age and 19% patients with renal impairment defined as eGFR <60 mL/min/1.73 m2. The mean eGFR was 77 mL/min/1.73 m2. Patients were taking at least one antidiabetic drug (91%) and the most common were metformin (83%) and sulfonylurea (28%). Patients were also taking antihypertensives (89%), lipid lowering drugs (70%) with 65% on statin, and aspirin (47%).
The primary endpoint, MACE, was the time to first occurrence of one of three composite outcomes which included cardiovascular death, non-fatal myocardial infarction or non-fatal stroke. The trial was designed as a non-inferiority trial with a pre-specified risk margin of 1.3 for the upper bound of the 95% CI for the hazard ratio of MACE.
The results of CAROLINA, including the contribution of each component to the primary composite endpoint, are shown in Table 13. The Kaplan-Meier curve depicting time to first occurrence of MACE is shown in Figure 3.
Table 13: Major Adverse Cardiovascular Events (MACE) by Treatment Group in the CAROLINA Trial
|
Linagliptin 5 mg
n=3,023 |
Glimepiride (1 mg to 4 mg)
n=3,010 |
Hazard Ratio |
|
Number of Subjects (%) |
Incidence Rate per 1,000 PY* |
Number of Subjects (%) |
Incidence Rate per 1,000 PY* |
(95% CI) |
| Composite of first event of CV death, non-fatal myocardial infarction (MI), or non-fatal stroke (MACE) |
356 (11.8) |
20.7 |
362 (12.0) |
21.2 |
0.98
(0.84, 1.14) |
| CV death** |
169 (5.6) |
9.2 |
168 (5.6) |
9.2 |
1.00
(0.81, 1.24) |
| Non-fatal MI** |
145 (4.8) |
8.3 |
142 (4.7) |
8.2 |
1.01
(0.80, 1.28) |
| Non-fatal stroke** |
91 (3.0) |
5.2 |
104 (3.5) |
6.0 |
0.87
(0.66, 1.15) |
*PY=patient years
**A patient may have experienced more than one component; therefore, the sum of the components is larger than the number of patients who experienced the composite outcome |
Figure 3 Time to First Occurrence of 3P-MACE in CAROLINA