Study background: The objective of this collated research paper is to highlight the anti-diabetic effects and mode of action of imeglimin, the first in a new tetrahydrotriazine-containing class of oral anti-diabetic agents: the glimins. Imeglimin acts on both insulin resistant organs (liver and muscle) and pancreatic β-cells (insulin secretion in response to glucose and protection against apoptosis). Methods:The aim of the investigations reported here is to present data on the mode of action of imeglimin and its anti-diabetic effects, demonstrating that it represents a promising treatment for type 2 diabetes by acting on the three key pathological defects of the disease, namely excessive hepatic glucose production, impaired peripheral glucose uptake by skeletal muscle, and insufficient insulin secretion.Results: Imeglimin significantly lowered fasting plasma glucose concentrations in a dose-dependent manner in STZ rats. HbA1c was significantly reduced (P<0.01) by imeglimin (6.2%) compared with controls (9.83%). At a 150 mg·kg -1 dose, imeglimin significantly improved glucose tolerance compared with controls (AUC 0-3h 2,402 vs 3,449 mmol·L·h -1 respectively). With regards to its mode of action, imeglimin significantly decreased the rate of hepatic gluconeogenesis, stimulated muscle glucose uptake, induced a potentiation of glucose-dependent insulin secretion, and decreased β-cell apoptosis. Conclusion:Our investigations found that imeglimin uniquely targets the three key defects of type 2 diabetes. It could provide more durable, sustained glycemic control than currently achieved with oral anti-diabetics and has the potential to be used at any stage in the disease continuum. Imeglimin's potential for combination with other oral antidiabetics is also under investigation.

The results from both studies confirm that imeglimin displays a superior benefit : risk profile compared with metformin in type 2 diabetes patients. The encouraging tolerability profile of imeglimin could make it suitable for combination with other classes of antidiabetic agents and may increase availability to a wider patient population.

Imeglimin is an investigational first‐in‐class novel oral agent for the treatment of type 2 diabetes (T2D). Several pivotal phase III trials have been completed with evidence of statistically significant glucose lowering and a generally favourable safety and tolerability profile, including the lack of severe hypoglycaemia. Imeglimin's mechanism of action involves dual effects: (a) amplification of glucose‐stimulated insulin secretion (GSIS) and preservation of β‐cell mass; and (b) enhanced insulin action, including the potential for inhibition of hepatic glucose output and improvement in insulin signalling in both liver and skeletal muscle. At a cellular and molecular level, Imeglimin's underlying mechanism may involve correction of mitochondrial dysfunction, a common underlying element of T2D pathogenesis. It has been observed to rebalance respiratory chain activity (partial inhibition of Complex I and correction of deficient Complex III activity), resulting in reduced reactive oxygen species formation (decreasing oxidative stress) and prevention of mitochondrial permeability transition pore opening (implicated in preventing cell death). In islets derived from diseased rodents with T2D, Imeglimin also enhances glucose‐stimulated ATP generation and induces the synthesis of nicotinamide adenine dinucleotide (NAD+) via the ‘salvage pathway’. In addition to playing a key role as a mitochondrial co‐factor, NAD+ metabolites may contribute to the increase in GSIS (via enhanced Ca++ mobilization). Imeglimin has also been shown to preserve β‐cell mass in rodents with T2D. Overall, Imeglimin appears to target a key root cause of T2D: defective cellular energy metabolism. This potential mode of action is unique and has been shown to differ from that of other major therapeutic classes, including biguanides, sulphonylureas and glucagon‐like peptide‐1 receptor agonists.

OBJECTIVEA 12-week study assessed the efficacy and safety of a new oral antidiabetic agent, imeglimin, as add-on therapy in type 2 diabetes patients inadequately controlled with metformin alone.RESEARCH DESIGN AND METHODSA total of 156 patients were randomized 1:1 to receive imeglimin (1,500 mg twice a day) or placebo added to a stable dose of metformin (1,500–2,000 mg/day). Change in A1C from baseline was the primary efficacy outcome; secondary outcomes included fasting plasma glucose (FPG) and proinsulin/insulin ratio.RESULTSAfter 12 weeks, the placebo-subtracted decrease in A1C with metformin-imeglimin was −0.44% (P < 0.001). Metformin-imeglimin also significantly improved FPG and the proinsulin/insulin ratio from baseline (−0.91 mg/dL and −7.5, respectively) compared with metformin-placebo (0.36 mg/dL and 11.81). Metformin-imeglimin therapy was generally well-tolerated with a comparable safety profile to metformin-placebo.CONCLUSIONSAddition of imeglimin to metformin improved glycemic control and offers potential as a new treatment for type 2 diabetes.

Aim To assess the efficacy and safety of imeglimin monotherapy compared with placebo for 24 weeks in Japanese patients with type 2 diabetes (T2D). Materials and Methods In this 24‐week, randomized, double‐blind, placebo‐controlled, parallel‐group, dose‐ranging, phase 2b clinical trial, Japanese adults (age ≥ 20 years) with T2D either treatment‐naïve or previously treated with one oral antidiabetes agent were eligible for participation. Patients were randomly assigned (1:1:1:1) to receive orally imeglimin 500, 1000 or 1500 mg, or placebo twice‐daily over a 24‐week period. The primary endpoint was the placebo‐adjusted change at week 24 in HbA1c. Safety outcomes were assessed in all patients who received at least one dose of study drug. Results A total of 299 patients were randomized to receive double‐blind treatment with orally twice‐daily placebo (n = 75), imeglimin 500 mg (n = 75), 1000 mg (n = 74) or 1500 mg (n = 75). At week 24, imeglimin significantly decreased HbA1c (difference vs. placebo: imeglimin 500 mg −0.52% [95% CI: −0.77%, −0.27%], imeglimin 1000 mg −0.94% [95% CI: −1.19%, −0.68%], imeglimin 1500 mg −1.00% [95% CI: −1.26%, −0.75%]; P < .0001 for all). Treatment‐emergent adverse events were reported for 68.0%, 62.2%, 73.3% and 68.0% of patients receiving imeglimin 500, 1000 or 1500 mg and placebo, respectively. A small increase in gastrointestinal adverse effects (e.g. diarrhoea) occurred with the 1500 mg dose level. Hypoglycaemia was balanced among groups. Conclusions Imeglimin as monotherapy in Japanese patients with T2D was well tolerated and significantly improved glycaemic control with no significant increase in hypoglycaemic events versus placebo. Given the marginal increase in efficacy with the 1500 versus 1000 mg dose (along with the potential for gastrointestinal tolerability issues), a dose of 1000 mg twice‐daily was selected for subsequent phase 3 studies.