Pharmacotherapeutic group: Drugs used in diabetes, combinations of blood glucose lowering drugs, ATC code: A10BD16.
Mechanism of action
Vokanamet combines two oral glucose-lowering medicinal products with different and complementary mechanisms of action to improve glycaemic control in patients with type 2 diabetes: canagliflozin, an inhibitor of SGLT2 transporter, and metformin hydrochloride, a member of the biguanide class.
Canagliflozin
The SGLT2 transporter, expressed in the proximal renal tubules, is responsible for the majority of the reabsorption of filtered glucose from the tubular lumen. Patients with diabetes have been shown to have elevated renal glucose reabsorption which may contribute to persistent elevated blood glucose concentrations. Canagliflozin is an orally-active inhibitor of SGLT2. By inhibiting SGLT2, canagliflozin reduces reabsorption of filtered glucose and lowers the renal threshold for glucose (RTG), and thereby increases UGE, lowering elevated plasma glucose concentrations by this insulin-independent mechanism in patients with type 2 diabetes. The increased UGE with SGLT2 inhibition also translates to an osmotic diuresis, with the diuretic effect leading to a reduction in systolic blood pressure; the increase in UGE results in a loss of calories and therefore a reduction in body weight, as has been demonstrated in studies of patients with type 2 diabetes.
Canagliflozin's action to increase UGE directly lowering plasma glucose is independent of insulin. Improvement in homeostasis model assessment for beta-cell function (HOMA beta-cell) and improved beta-cell insulin secretion response to a mixed-meal challenge has been observed in clinical studies with canagliflozin.
In phase 3 studies, pre-meal administration of canagliflozin 300 mg once daily provided a greater reduction in postprandial glucose excursion than observed with the 100 mg once daily dose. This effect at the 300 mg dose of canagliflozin may, in part, be due to local inhibition of intestinal SGLT1 (an important intestinal glucose transporter) related to transient high concentrations of canagliflozin in the intestinal lumen prior to medicinal product absorption (canagliflozin is a low potency inhibitor of the SGLT1 transporter). Studies have shown no glucose malabsorption with canagliflozin.
Metformin
Metformin is a biguanide with antihyperglycaemic effects, lowering both basal and postprandial plasma glucose. It does not stimulate insulin secretion and therefore does not produce hypoglycaemia.
Metformin may act via three mechanisms:
• by reduction of hepatic glucose production by inhibiting gluconeogenesis and glycogenolysis
• in muscle, by increasing insulin sensitivity, improving peripheral glucose uptake and utilisation
• and delay of intestinal glucose absorption.
Metformin stimulates intracellular glycogen synthesis by acting on glycogen synthase. Metformin increases the transport capacity of the membrane glucose transporters GLUT-1 and GLUT-4.
In humans, independently of its action on glycaemia, metformin has favourable effects on lipid metabolism. This has been shown at therapeutic doses in controlled, medium-term, or long-term clinical studies: metformin reduces total cholesterol, LDL-C, and triglyceride levels.
Pharmacodynamic effects of canagliflozin
Following single and multiple oral doses of canagliflozin to patients with type 2 diabetes, dose-dependent decreases in RTG and increases in UGE were observed. From a starting value of RTG of approximately 13 mmol/L, maximal suppression of 24-hour mean RTG was seen with the 300 mg daily dose to approximately 4 mmol/L to 5 mmol/L in patients with type 2 diabetes in phase 1 studies, suggesting a low risk for treatment-induced hypoglycaemia. The reductions in RTG led to increased UGE in subjects with type 2 diabetes treated with either 100 mg or 300 mg once daily of canagliflozin ranging from 77 g/day to 119 g/day across the phase 1 studies; the UGE observed translates to a loss of 308 kcal/day to 476 kcal/day. The reductions in RTG and increases in UGE were sustained over a 26-week dosing period in patients with type 2 diabetes. Moderate increases (generally < 400 mL to 500 mL) in daily urine volume were seen that attenuated over several days of dosing. Urinary uric acid excretion was transiently increased by canagliflozin (increased by 19% compared to baseline on day 1 and then attenuating to 6% on day 2 and 1% on day 13). This was accompanied by a sustained reduction in serum uric acid concentration of approximately 20%.
In a single-dose study in patients with type 2 diabetes, treatment with 300 mg before a mixed meal delayed intestinal glucose absorption and reduced postprandial glucose through both a renal and a non-renal mechanism.
Clinical efficacy and safety
Both improvement in glycaemic control and reduction of cardiovascular morbidity and mortality are an integral part of the treatment of type 2 diabetes.
The co-administration of canagliflozin and metformin has been studied in patients with type 2 diabetes inadequately controlled on metformin either alone or in combination with other glucose-lowering medicinal products.
There have been no clinical efficacy studies conducted with Vokanamet; however, bioequivalence of Vokanamet to canagliflozin and metformin co-administered as individual tablets was demonstrated in healthy subjects.
Canagliflozin
Glycaemic efficacy and safety
A total of 10,501 patients with type 2 diabetes participated in ten double-blind, controlled clinical efficacy and safety studies conducted to evaluate the effects of canagliflozin on glycaemic control, including 5,151 patients treated with canagliflozin in combination with metformin. The racial distribution of patients who received canagliflozin was 72% White, 16% Asian, 5% Black, and 8% other groups. 17% of patients were Hispanic. 58% of patients were male. Patients had an overall mean age of 59.5 years (range 21 years to 96 years), with 3,135 patients ≥ 65 years of age and 513 patients ≥ 75 years of age. 58% of patients had a body mass index (BMI) ≥ 30 kg/m2. In the clinical development programme, 1,085 patients with a baseline eGFR 30 mL/min/1.73 m2 to < 60 mL/min/1.73 m2 were evaluated.
Placebo-controlled studies
Canagliflozin was studied as dual therapy with metformin, dual therapy with a sulphonylurea, triple therapy with metformin and a sulphonylurea, triple therapy with metformin and pioglitazone, as an add-on therapy with insulin, and as monotherapy (table 5). In general, canagliflozin produced clinically and statistically significant (p < 0.001) results relative to placebo in glycaemic control, including glycosylated haemoglobin (HbA1c), the percentage of patients achieving HbA1c < 7%, change from baseline fasting plasma glucose (FPG), and 2-hour postprandial glucose (PPG). In addition, reductions in body weight and systolic blood pressure relative to placebo were observed.
Furthermore, canagliflozin was studied as triple therapy with metformin and sitagliptin and dosed with a titration regimen, using a starting dose of 100 mg and titrated to 300 mg as early as week 6 in patients requiring additional glycaemic control who had appropriate eGFR and were tolerating canagliflozin 100 mg (table 5). Canagliflozin dosed with a titration regimen produced clinically and statistically significant (p < 0.001) results relative to placebo in glycaemic control, including HbA1c and change from baseline FPG, and a statistically significant (p < 0.01) improvement in the percentage of patients achieving HbA1c < 7%. In addition, reductions in body weight and systolic blood pressure relative to placebo were observed.
| Table 5: Efficacy results from placebo-controlled clinical studiesa |
| Dual therapy with metformin (26 weeks) |
| | Canagliflozin + metformin | Placebo + metformin (N = 183) |
| 100 mg (N = 368) | 300 mg (N = 367) |
| HbA1c (%) |
| Baseline (mean) | 7.94 | 7.95 | 7.96 |
| Change from baseline (adjusted mean) | -0.79 | -0.94 | -0.17 |
| Difference from placebo (adjusted mean) (95% CI) | -0.62b (-0.76; -0.48) | -0.77b (-0.91; -0.64) | N/Ac |
| Patients (%) achieving HbA1c < 7% | 45.5b | 57.8b | 29.8 |
| Body weight |
| Baseline (mean) in kg | 88.7 | 85.4 | 86.7 |
| % change from baseline (adjusted mean) | -3.7 | -4.2 | -1.2 |
| Difference from placebo (adjusted mean) (95% CI) | -2.5b (-3.1; -1.9) | -2.9b (-3.5; -2.3) | N/Ac |
| Triple therapy with metformin and sulphonylurea (26 weeks) |
| | Canagliflozin + metformin and sulphonylurea | Placebo + metformin and sulphonylurea (N = 156) |
| 100 mg (N = 157) | 300 mg (N = 156) |
| HbA1c (%) |
| Baseline (mean) | 8.13 | 8.13 | 8.12 |
| Change from baseline (adjusted mean) | -0.85 | -1.06 | -0.13 |
| Difference from placebo (adjusted mean) (95% CI) | -0.71b (-0.90; -0.52) | -0.92b (-1.11; -0.73) | N/Ac |
| Patients (%) achieving HbA1c < 7% | 43.2b | 56.6b | 18.0 |
| Body weight |
| Baseline (mean) in kg | 93.5 | 93.5 | 90.8 |
| % change from baseline (adjusted mean) | -2.1 | -2.6 | -0.7 |
| Difference from placebo (adjusted mean) (95% CI) | -1.4b (-2.1; -0.7) | -2.0b (-2.7; -1.3) | N/Ac |
| Add-on therapy with insulind (18 weeks) |
| | Canagliflozin + insulin | Placebo + insulin (N = 565) |
| 100 mg (N = 566) | 300 mg (N = 587) |
| HbA1c (%) |
| Baseline (mean) | 8.33 | 8.27 | 8.20 |
| Change from baseline (adjusted mean) | -0.63 | -0.72 | 0.01 |
| Difference from placebo (adjusted mean) (95% CI) | -0.65b (-0.73; -0.56) | -0.73b (-0.82; -0.65) | N/Ac |
| Patients (%) achieving HbA1c < 7% | 19.8b | 24.7b | 7.7 |
| Body weight |
| Baseline (mean) in kg | 96.9 | 96.7 | 97.7 |
| % change from baseline (adjusted mean) | -1.8 | -2.3 | 0.1 |
| Difference from placebo (adjusted mean) (97.5% CI) | -1.9b (-2.2; -1.5) | -2.4b (-2.8; -2.0) | N/Ac |
| Triple therapy with metformin and sitagliptine (26 weeks) |
| | Canagliflozin + metformin and sitaglipting (N = 107) | Placebo + metformin and sitagliptin (N = 106) |
| HbA1c (%) |
| Baseline (mean) | 8.53 | 8.38 |
| Change from baseline (adjusted mean) | -0.91 | -0.01 |
| Difference from placebo (adjusted mean) (95% CI) | -0.89b (-1.19; -0.59) | |
| Patients (%) achieving HbA1c < 7% | 32f | 12 |
| Fasting plasma glucose (mg/dL) |
| Baseline (mean) | 186 | 180 |
| Change from baseline (adjusted mean) | -30 | -3 |
| Difference from placebo (adjusted mean) (95% CI) | -27b (-40; -14) | |
| Body weight |
| Baseline (mean) in kg | 93.8 | 89.9 |
| % change from baseline (adjusted mean) | -3.4 | -1.6 |
| Difference from placebo (adjusted mean) (95% CI) | -1.8b (-2.7; -0.9) | |
| a Intent-to-treat population using last observation in study prior to glycaemic rescue therapy. b p < 0.001 compared to placebo. c Not applicable. d Canagliflozin as add-on therapy to insulin (with or without other glucose-lowering medicinal products). e Canagliflozin 100 mg uptitrated to 300 mg f p < 0.01 compared to placebo g 90.7% of subjects in the canagliflozin group uptitrated to 300 mg |
In addition to the studies presented above, glycaemic efficacy results observed in an 18-week dual therapy sub-study with a sulphonylurea and a 26-week triple therapy study with metformin and pioglitazone were generally comparable with those observed in other studies.
A dedicated study demonstrated that co-administration of canagliflozin 50 mg and 150 mg dosed twice daily as dual therapy with metformin produced clinically and statistically significant results relative to placebo in glycaemic control, including HbA1c, the percentage of patients achieving HbA1c < 7%, change from baseline FPG, and in reductions in body weight as shown in table 6.
| Table 6: Efficacy results from placebo-controlled clinical study of canagliflozin dosed twice dailya |
| | Canagliflozin | Placebo (N = 93) |
| 50 mg twice daily (N = 93) | 150 mg twice daily (N = 93) |
| HbA1c (%) |
| Baseline (mean) | 7.63 | 7.53 | 7.66 |
| Change from baseline (adjusted mean) | -0.45 | -0.61 | -0.01 |
| Difference from placebo (adjusted mean) (95% CI) | -0.44b (-0.637; -0.251) | -0.60b (-0.792; -0.407) | N/Ac |
| Patients (%) achieving HbA1c < 7% | 47.8d | 57.1b | 31.5 |
| Body weight |
| Baseline (mean) in kg | 90.59 | 90.44 | 90.37 |
| % change from baseline (adjusted mean) | -2.8 | -3.2 | -0.6 |
| Difference from placebo (adjusted mean) (95% CI) | -2.2b (-3.1; -1.3) | -2.6b (-3.5; -1.7) | N/Ac |
| a Intent-to-treat population using last observation in study. b p < 0.001 compared to placebo. c Not applicable. d p = 0.013 compared to placebo. |
Active-controlled studies
Canagliflozin was compared to glimepiride as dual therapy with metformin and compared to sitagliptin as triple therapy with metformin and a sulphonylurea (table 7). Canagliflozin 100 mg once daily as dual therapy with metformin produced similar reductions in HbA1c from baseline and 300 mg produced superior (p < 0.05) reductions in HbA1c compared to glimepiride, thus demonstrating non-inferiority. A lower proportion of patients treated with canagliflozin 100 mg once daily (5.6%) and canagliflozin 300 mg once daily (4.9%) experienced at least one episode/event of hypoglycaemia over 52 weeks of treatment compared to the group treated with glimepiride (34.2%). In a study comparing canagliflozin 300 mg once daily to sitagliptin 100 mg in triple therapy with metformin and a sulphonylurea, canagliflozin demonstrated non-inferior (p < 0.05) and superior (p < 0.05) reduction in HbA1c relative to sitagliptin. The incidence of hypoglycaemia episodes/events with canagliflozin 300 mg once daily and sitagliptin 100 mg was 40.7% and 43.2%, respectively. Significant improvements in body weight and reductions in systolic blood pressure compared to both glimepiride and sitagliptin were also observed.
| Table 7: Efficacy results from active-controlled clinical studiesa |
| Compared to glimepiride as dual therapy with metformin (52 weeks) |
| | Canagliflozin + metformin | Glimepiride (titrated) + metformin (N = 482) |
| 100 mg (N = 483) | 300 mg (N = 485) |
| HbA1c (%) |
| Baseline (mean) | 7.78 | 7.79 | 7.83 |
| Change from baseline (adjusted mean) | -0.82 | -0.93 | -0.81 |
| Difference from glimepiride (adjusted mean) (95% CI) | -0.01b (−0.11; 0.09) | -0.12b (−0.22; −0.02) | N/Ac |
| Patients (%) achieving HbA1c < 7% | 53.6 | 60.1 | 55.8 |
| Body weight |
| Baseline (mean) in kg | 86.8 | 86.6 | 86.6 |
| % change from baseline (adjusted mean) | -4.2 | -4.7 | 1.0 |
| Difference from glimepiride (adjusted mean) (95% CI) | -5.2b (−5.7; −4.7) | -5.7b (−6.2; −5.1) | N/Ac |
| Compared to sitagliptin as triple therapy with metformin and sulphonylurea (52 weeks) |
| | Canagliflozin 300 mg + metformin and sulphonylurea (N = 377) | Sitagliptin 100 mg + metformin and sulphonylurea (N = 378) |
| HbA1c (%) |
| Baseline (mean) | 8.12 | 8.13 |
| Change from baseline (adjusted mean) | -1.03 | -0.66 |
| Difference from sitagliptin (adjusted mean) (95% CI) | -0.37b (-0.50; -0.25) | N/A |
| Patients (%) achieving HbA1c < 7% | 47.6 | 35.3 |
| Body weight |
| Baseline (mean) in kg | 87.6 | 89.6 |
| % change from baseline (adjusted mean) | -2.5 | 0.3 |
| Difference from sitagliptin (adjusted mean) (95% CI) | -2.8d (-3.3; -2.2) | N/A |
| a Intent-to-treat population using last observation in study prior to glycaemic rescue therapy. b p < 0.05. c Not applicable. d p < 0.001. |
Canagliflozin as initial combination therapy with metformin
Canagliflozin was evaluated in combination with metformin as initial combination therapy in patients with type 2 diabetes failing diet and exercise. Canagliflozin 100 mg and canagliflozin 300 mg in combination with metformin XR resulted in a statistically significant greater improvement in HbA1c compared to their respective canagliflozin doses (100 mg and 300 mg) alone or metformin XR alone (table 8).
| Table 8: Results from 26-week active-controlled clinical study of canagliflozin as initial combination therapy with metformin* |
| Efficacy parameter | Metformin XR (N = 237) | Canagliflozin 100 mg (N = 237) | Canagliflozin 300 mg (N = 238) | Canagliflozin 100 mg + metformin XR (N = 237) | Canagliflozin 300 mg + metformin XR (N = 237) |
| HbA1c (%) |
| Baseline (mean) | 8.81 | 8.78 | 8.77 | 8.83 | 8.90 |
| Change from baseline (adjusted mean) | -1.30 | -1.37 | -1.42 | -1.77 | -1.78 |
| Difference from canagliflozin 100 mg (adjusted mean) (95% CI) † | | | | -0.40‡ (-0.59, -0.21) | |
| Difference from canagliflozin 300 mg (adjusted mean) (95% CI) † | | | | | -0.36‡ (-0.56, -0.17) |
| Difference from metformin XR (adjusted mean) (95% CI) † | | -0.06‡ (-0.26, 0.13) | -0.11‡ (-0.31, 0.08) | -0.46‡ (-0.66, -0.27) | -0.48‡ (-0.67, -0.28) |
| Percent of patients achieving HbA1c < 7% | 43 | 39 | 43 | 50§§ | 57§§ |
| Body weight |
| Baseline (mean) in kg | 92.1 | 90.3 | 93.0 | 88.3 | 91.5 |
| % change from baseline (adjusted mean) | -2.1 | -3.0 | -3.9 | -3.5 | -4.2 |
| Difference from metformin XR (adjusted mean) (95% CI)† | | -0.9§§ (-1.6, -0.2) | -1.8§ (-2.6, -1.1) | -1.4‡ (-2.1, -0.6) | -2.1‡ (-2.9, -1.4) |
| * Intent-to-treat population † Least squares mean adjusted for covariates including baseline value and stratification factor ‡ Adjusted p = 0.001 § Adjusted p < 0.01 §§ Adjusted p < 0.05 |
Special populations
In three studies conducted in special populations (elderly patients, patients with an eGFR of 30 mL/min/1.73 m2 to < 50 mL/min/1.73 m2 and patients with or at high risk for cardiovascular disease), canagliflozin was added to patients' current stable diabetes treatments (diet, monotherapy, or combination therapy).
Elderly
A total of 714 patients ≥ 55 years of age to ≤ 80 years of age (227 patients 65 years of age to < 75 years of age and 46 patients 75 years of age to ≤ 80 years of age) with inadequate glycaemic control on current diabetes treatment (glucose-lowering medicinal products and/or diet and exercise) participated in a double-blind, placebo-controlled study over 26 weeks. Statistically significant (p < 0.001) changes from baseline HbA1c relative to placebo of -0.57% and -0.70% were observed for 100 mg once daily and 300 mg once daily, respectively (see sections 4.2 and 4.8).
Patients with eGFR 45 mL/min/1.73 m2 to < 60 mL/min/1.73 m2
In a pooled analysis of patients (N = 721) with a baseline eGFR 45 mL/min/1.73 m2 to < 60 mL/min/1.73 m2, canagliflozin provided clinically meaningful reduction in HbA1c compared to placebo, with -0.47% for canagliflozin 100 mg and -0.52% for canagliflozin 300 mg. Patients with a baseline eGFR 45 mL/min/1.73 m2 to < 60 mL/min/1.73 m2 treated with canagliflozin 100 mg and 300 mg exhibited mean improvements in percent change in body weight relative to placebo of -1.8% and -2.0%, respectively.
The majority of patients with a baseline eGFR 45 mL/min/1.73 m2 to < 60 mL/min/1.73 m2 were on insulin and/or a sulphonylurea (85% [614/721]). Consistent with the expected increase of hypoglycaemia when a medicinal product not associated with hypoglycaemia is added to insulin and/or sulphonylurea, an increase in hypoglycaemia episodes/events was seen when canagliflozin was added to insulin and/or a sulphonylurea (see section 4.8).
Fasting plasma glucose
In four placebo-controlled studies, treatment with canagliflozin as monotherapy or add-on therapy with one or two oral glucose-lowering medicinal products resulted in mean changes from baseline relative to placebo in FPG of -1.2 mmol/L to -1.9 mmol/L for canagliflozin 100 mg once daily and -1.9 mmol/L to -2.4 mmol/L for canagliflozin 300 mg once daily, respectively. These reductions were sustained over the treatment period and near maximal after the first day of treatment.
Postprandial glucose
Using a mixed-meal challenge, canagliflozin as monotherapy or add-on therapy with one or two oral glucose-lowering medicinal products reduced postprandial glucose from baseline relative to placebo by -1.5 mmol/L to -2.7 mmol/L for canagliflozin 100 mg once daily and -2.1 mmol/L to -3.5 mmol/L for canagliflozin 300 mg once daily, respectively, due to reductions in the pre-meal glucose concentration and reduced postprandial glucose excursions.
Body weight
Canagliflozin 100 mg and 300 mg once daily in dual or triple add-on therapy with metformin resulted in statistically significant reductions in the percentage of body weight at 26 weeks relative to placebo. In two 52-week active-controlled studies comparing canagliflozin to glimepiride and sitagliptin, sustained and statistically significant mean reductions in the percentage of body weight for canagliflozin as add-on therapy to metformin were -4.2% and -4.7% for canagliflozin 100 mg and 300 mg once daily, respectively, compared to the combination of glimepiride and metformin (1.0%) and -2.5% for canagliflozin 300 mg once daily in combination with metformin and a sulphonylurea compared to sitagliptin in combination with metformin and a sulphonylurea (0.3%).
A subset of patients (N = 208) from the active-controlled dual therapy study with metformin who underwent dual energy X-ray densitometry (DXA) and abdominal computed tomography (CT) scans for evaluation of body composition demonstrated that approximately two-thirds of the weight loss with canagliflozin was due to loss of fat mass with similar amounts of visceral and abdominal subcutaneous fat being lost. 211 patients from the clinical study in older patients participated in a body composition substudy using DXA body composition analysis. This demonstrated that approximately two-thirds of the weight loss associated with canagliflozin was due to loss of fat mass relative to placebo. There were no meaningful changes in bone density in trabecular and cortical regions.
Blood pressure
In placebo-controlled studies, treatment with canagliflozin 100 mg and 300 mg resulted in mean reductions in systolic blood pressure of -3.9 mmHg and -5.3 mmHg, respectively, compared to placebo (-0.1 mmHg) and a smaller effect on diastolic blood pressure with mean changes for canagliflozin 100 mg and 300 mg of -2.1 mmHg and -2.5 mmHg, respectively, compared to placebo (-0.3 mmHg). There was no notable change in heart rate.
Patients with baseline HbA1c > 10% to ≤ 12%
A substudy of patients with baseline HbA1c > 10% to ≤ 12% with canagliflozin as monotherapy resulted in reductions from baseline in HbA1c (not placebo-adjusted) of -2.13% and -2.56% for canagliflozin 100 mg and 300 mg, respectively.
Cardiovascular outcomes in the CANVAS Program
The effect of canagliflozin on cardiovascular events in adults with type 2 diabetes who had established cardiovascular (CV) disease or were at risk for CVD (two or more CV risk factors), was evaluated in the CANVAS Program (integrated analysis of the CANVAS and the CANVAS-R study). These studies were multi-centre, multi-national, randomised, double-blind, parallel group, with similar inclusion and exclusion criteria and patient populations. The CANVAS Program compared the risk of experiencing a Major Adverse Cardiovascular Event (MACE) defined as the composite of cardiovascular death, nonfatal myocardial infarction and nonfatal stroke, between canagliflozin and placebo on a background of standard of care treatments for diabetes and atherosclerotic cardiovascular disease.
In CANVAS, subjects were randomly assigned 1:1:1 to canagliflozin 100 mg, canagliflozin 300 mg, or matching placebo. In CANVAS-R, subjects were randomly assigned 1:1 to canagliflozin 100 mg or matching placebo, and titration to 300 mg was permitted (based on tolerability and glycaemic needs) after Week 13. Concomitant antidiabetic and atherosclerotic therapies could be adjusted, according to the standard care for these diseases.
A total of 10,134 patients were treated (4,327 in CANVAS and 5,807 in CANVAS-R; total of 4,344 randomly assigned to placebo and 5,790 to canagliflozin) for a mean exposure duration of 149 weeks (223 weeks in CANVAS and 94 weeks in CANVAS-R). Vital status was obtained for 99.6% of subjects across the studies. The mean age was 63 years and 64% were male. Sixty-six percent of subjects had a history of established cardiovascular disease, with 56% having a history of coronary disease, 19% with cerebrovascular disease, and 21% with peripheral vascular disease; 14% had a history of heart failure.
The mean HbA1c at baseline was 8.2% and mean duration of diabetes was 13.5 years.
Baseline renal function was normal or mildly impaired in 80% of patients and moderately impaired in 20% of patients (mean eGFR 77 mL/min/1.73 m2). At baseline, patients were treated with one or more antidiabetic medicinal products including metformin (77%), insulin (50%), and sulfonylurea (43%).
The primary endpoint in the CANVAS Program was the time to first occurrence of a MACE. Secondary endpoints within a sequential conditional hypothesis testing were all-cause mortality and cardiovascular mortality.
Patients in the pooled canagliflozin groups (pooled analysis of canagliflozin 100 mg, canagliflozin 300 mg, and canagliflozin up-titrated from 100 mg to 300 mg) had a lower rate of MACE as compared to placebo: 2.69 versus 3.15 patients per 100 patient-years (HR of the pooled analysis: 0.86; 95% CI (0.75, 0.97).
Based on the Kaplan-Meier plot for the first occurrence of MACE, shown below, the reduction in MACE in the canagliflozin group was observed as early as Week 26 and was maintained throughout the remainder of the study (see Figure 1).
Figure 1: Time to first occurrence of MACE
There were 2,011 patients with eGFR 30 to < 60 mL/min/1.73 m2. The MACE findings in this subgroup were consistent with the overall findings.
Each MACE component positively contributed to the overall composite, as shown in Figure 2. Results for the 100 mg and 300 mg canagliflozin doses were consistent with results for the combined dose groups.
Figure 2: Treatment effect for the primary composite endpoint and its components
1 P value for superiority (2-sided) = 0.0158.
All-cause mortality
In the combined canagliflozin group, the HR for all-cause mortality versus placebo was 0.87 (0.74, 1.01).
Heart failure requiring hospitalisation
Canagliflozin reduced the risk for heart failure requiring hospitalisation compared to placebo (HR: 0.67; 95% CI (0.52, 0.87)).
Renal endpoints
In the CANVAS Program, for time to first adjudicated nephropathy event (doubling of serum creatinine, need for renal-replacement therapy, and renal death), the HR was 0.53 (95% CI: 0.33, 0.84) for canagliflozin (0.15 events per 100 patient-years) versus placebo (0.28 events per 100 patient-years). In addition, canagliflozin reduced progression of albuminuria 25.8% versus placebo 29.2% (HR: 0.73; 95% CI: 0.67, 0.79) in patients with baseline normo- or micro-albuminuria.
Canagliflozin 100 mg has also been studied in adults with type 2 diabetes and diabetic kidney disease with estimated glomerular filtration rate (eGFR) 30 to < 90 mL/min/1.73 m2 and albuminuria (˃ 33.9 to 565.6 mg/mmol of creatinine). No information in this patient population is available for the canagliflozin/metformin fixed dose combination.
Metformin
The prospective randomised (UKPDS) study has established the long-term benefit of intensive blood glucose control in type 2 diabetes. Analysis of the results for overweight patients treated with metformin after failure of diet alone showed:
• a significant reduction of the absolute risk of any diabetes-related complication in the metformin group (29.8 events/1,000 patient-years) versus diet alone (43.3 events/1,000 patient-years), p = 0.0023, and versus the combined sulphonylurea and insulin monotherapy groups (40.1 events/1,000 patient-years), p = 0.0034
• a significant reduction of the absolute risk of any diabetes-related mortality: metformin 7.5 events/1,000 patient-years, diet alone 12.7 events/1,000 patient-years, p = 0.017
• a significant reduction of the absolute risk of overall mortality: metformin 13.5 events/1,000 patient-years versus diet alone 20.6 events/1,000 patient-years, (p = 0.011), and versus the combined sulphonylurea and insulin monotherapy groups 18.9 events/1,000 patient-years (p = 0.021)
• a significant reduction in the absolute risk of myocardial infarction: metformin 11 events/1,000 patient-years, diet alone 18 events/1,000 patient-years, (p = 0.01).
Paediatric population
The European Medicines Agency has waived the obligation to submit the results of studies with Vokanamet in all subsets of the paediatric population in type 2 diabetes (see section 4.2 for information on paediatric use).