GLP-1 receptor agonists or DPP-4 inhibitors: how to guide the clinician?

DR10627, a Novel Dual Glucagon‑like Peptide‑1 and Gastric Inhibitory Polypeptide Receptor Agonist for the Treatment of Obesity and Type 2 Diabetes Mellitus

Introduction

Diabetes and obesity are momentous risk factors threatening people's lives and health. Currently available incretin analogue glucagon-like peptide 1 (GLP-1) possesses huge hypoglycemic effect with the unsatisfactory effect of weight loss. Co-agonists targeting GLP-1R plus glucagon receptor (GCGR) or gastric inhibitory polypeptide receptor (GIPR) show synergistic benefits in glycaemic control and weight loss. Here, we describe a novel dual GIP and GLP-1 receptor agonist, DR10627, and performed a preclinical assessment of it.

Methods

The agonistic ability of DR10627 was indirectly assessed by inducing cAMP accumulation in Chinese hamster ovary (CHO) cells transfected with GLP-1R or GIPR in vitro. The plasma pharmacokinetics of DR10627 were analysed in cynomolgus monkeys. The OGTTs were performed in Sprague‑Dawley (SD) rats. The glucose lowering effects were evaluated by repeated administration of DR10627 in diabetic (db/db) mice for 4 weeks. The effects of anti-obesity and improving metabolism of DR10627 were evaluated by repeated administration of DR10627 in diet-induced obesity (DIO) mice for 57 days.

Results

DR10627 had the capacity to activate both GLP-1R and GIPR in vitro. The terminal half-life of DR10627 was found to be approximately 4.19-5.8 h in cynomolgus monkeys. DR10627 had a great improvement in oral glucose tolerance in SD rats. Moreover, DR10627 had a potent glucose-lowering effect in db/db mice, and the hypoglycemic effect of 18 nmol/kg DR10627 was better than that of 50 nmol/kg liraglutide. In addition, 10 and 30 nmol/kg DR10627 possessed the ability of potentiating the weight-loss, lipid-lowing efficacy and improving metabolism to a greater extent than 80 nmol/kg liraglutide.

Conclusion

Preclinical assessment demonstrated that administration of DR10627 resulted in glucose lowering in SD rats and db/db mice, and substantial body weight reduction and metabolism improvement in DIO mice. DR10627 is a promising agent deserving further investigation for the treatment of type 2 diabetes and obesity.

Clinical pharmacology of antidiabetic drugs: What can be expected of their use?

The pharmacotherapy of type 2 diabetes mellitus (T2DM) has markedly evolved in the last two decades. Classical antidiabetic agents (sulphonylureas, metformin, insulin) are now in competition with new glucose-lowering medications. Alpha-glucosidase inhibitors and thiazolidinediones (glitazones) were not able to replace older agents, because of insufficient efficacy and/or poor tolerability/safety. In contrast, incretin-based therapies, both dipeptidyl peptidase-4 inhibitors (DPP-4is or gliptins, oral agents) and glucagon-like peptide-1 receptor agonists (GLP-1RAs, subcutaneous injections) are a major breakthrough in the management of T2DM. Because they are not associated with hypoglycaemia and weight gain, DPP-4is tend to replace sulphonylureas as add-on to metformin while GLP-1RAs tend to replace basal insulin therapy after failure of oral therapies. Furthermore, placebo-controlled cardiovascular outcome trials demonstrated neutrality for DPP-4is, but cardiovascular protection for GLP-1RAs in patients with T2DM at high cardiovascular risk. More recently sodium-glucose cotransporter 2 inhibitors (SGLT2is or gliflozins, oral agents) also showed cardiovascular protection, especially a reduction in hospitalization for heart failure, as well as a renal protection in patients with and without T2DM, at high cardiovascular risk, with established heart failure and/or with chronic kidney disease. Thus, GLP-1RAs and SGLT2is are now considered as preferred drugs in T2DM patients with or at high risk of atherosclerotic cardiovascular disease whereas SGLT2is are more specifically recommended in patients with or at risk of heart failure and renal (albuminuric) disease. The management of T2DM is moving from a glucocentric approach to a broader strategy focusing on all risk factors, including overweight/obesity, and to an organ-disease targeted personalized approach.

Dual GIP/GLP-1 receptor agonists: New advances for treating type-2 diabetes

Glucagon-like peptide-1 (GLP-1) receptor agonists currently occupy a privileged place in the management of type-2 diabetes (T2D). Dual glucose-dependent insulinotropic polypeptides (GIP/GLP-1) have been recently developed. Tirzepatide is the most advanced unimolecular dual GIP/GLP-1 receptor agonist to be used as once weekly subcutaneous injection in T2D and recently received approval by the European Medicines Agency. Because of the complementarity of action of the two incretins, tirzepatide showed better dose-dependent (5, 10 and 15mg) efficacy (greater reduction in HbA1c and body weight) than placebo, basal insulin or two GLP-1 analogues (dulaglutide and semaglutide) in the SURPASS program. Its cardiovascular protective effect is currently being assessed versus dulaglutide in the SURPASS-CVOT study. Finally, studies for the treatment of obesity (SURMOUNT program) and metabolic-associated fatty liver disease (MAFLD) are also ongoing. Gastrointestinal tolerance of tirzepatide appears comparable to that of GLP-1 analogues, except for higher incidence of diarrhea. Other original molecules have been built, including triple GIP/GLP-1/glucagon receptor agonists. The risk/benefit ratio will decide whether dual (or triple) receptor agonists should replace pure GLP-1 receptor agonists for the management of T2D in the near future, with a significant role in the pharmacotherapy of obesity.

Dulaglutide-induced cerebral venous thrombosis in a patient with type 2 diabetes mellitus

Though patients with diabetes mellitus are at a high risk of atherothrombotic events, every such event should not be attributed to the disease itself. We present a case of a patient with diabetes with headache and blurring of vision for 3 days. Brain imaging revealed right transverse sinus thrombosis and acute infarct of the right posterior parieto-occipital region, predominantly in the posterior cortical watershed zone. The patient was on subcutaneous dulaglutide for 3 weeks and was having nausea and vomiting. Various causes of cerebral venous thrombosis were ruled out with appropriate laboratory investigations. Finally, cerebral venous thrombosis was attributed to dulaglutide-induced nausea and vomiting which led to severe dehydration.

Cardiovascular outcome studies with incretin-based therapies: Comparison between DPP-4 inhibitors and GLP-1 receptor agonists

Dipeptidyl peptidase-4 inhibitors (DPP-4is) and glucagon-like peptide-1 receptor agonists (GLP-1RAs) represent two distinct classes of incretin-based therapies used for the treatment of type 2 diabetes. Non-inferiority versus placebo was shown in large prospective cardiovascular outcome trials in patients with high cardiovascular risk: SAVOR-TIMI 53 (saxagliptin), EXAMINE (alogliptin), and TECOS (sitagliptin); ELIXA (lixisenatide), LEADER (liraglutide) and SUSTAIN 6 (semaglutide). The promises raised by meta-analyses of phase 2-3 trials with DPP-4is were non confirmed as no cardiovascular protection could be evidenced. However, LEADER showed a significant reduction in major cardiovascular events, myocardial infarction, cardiovascular and all-cause mortality in patients treated by liraglutide compared to placebo. These positive results contrasted with the non-inferiority results with lixisenatide in ELIXA. They were partially confirmed with semaglutide in SUSTAIN 6 despite the absence of reduction in cardiovascular mortality. Hospitalisation for heart failure was not increased except with saxagliptin in SAVOR-TIMI 53. The reasons for different outcomes between trials remain largely unknown as well as the precise underlying mechanisms explaining the cardiovascular protection by liraglutide. The clinical relevance of results with DPP-4is and GLP-1RAs is discussed. Ongoing trials with linagliptin and several once-weekly GLP-1RAs should provide new insights into remaining fundamental questions.

Efficacy and Acceptability of Glycemic Control of Glucagon-Like Peptide-1 Receptor Agonists among Type 2 Diabetes: A Systematic Review and Network Meta-Analysis

Objective

To synthesize current evidence of the impact of Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) on hypoglycemia, treatment discontinuation and glycemic level in patients with type 2 diabetes.

Design

Systematic review and network meta-analysis.

Data Sources

Literature search (Medline, Embase, the Cochrane library), website of clinical trial, bibliographies of published systematic reviews.

Eligibility Criteria

Randomized controlled trials with available data comparing GLP-1 RAs with placebo or traditional anti-diabetic drugs in patients with type 2 diabetes.

Data Synthesis

Traditional pairwise meta-analyses within DerSimonian-Laird random effects model and network meta-analysis within a Bayesian framework were performed to calculate odds ratios for the incidence of hypoglycemia, treatment discontinuation, HbA1c<7.0% and HbA1c<6.5%. Ranking probabilities for all treatments were estimated to obtain a treatment hierarchy using the surface under the cumulative ranking curve (SUCRA) and mean ranks.

Results

78 trials with 13 treatments were included. Overall, all GLP-1 RAs except for albiglutide increased the risk of hypoglycemia when compared to placebo. Reduction in the incidence of hypoglycemia was found for all GLP-1 RAs versus insulin (except for dulaglutide) and sulphonylureas. For the incidence of treatment discontinuation, increase was found for exenatide, liraglutide, lixisenatide and taspoglutide versus placebo, insulin and sitagliptin. For glycemic level, decrease was found for all GLP-1 RAs versus placebo. Dulaglutide, exenatide long-acting release (exe_lar), liraglutide and taspoglutide had significant lowering effect when compared with sitagliptin (HbA1c<7.0%) and insulin (HbA1c<6.5%). Finally, according to SUCRAs, placebo, thiazolidinediones and albiglutide had the best decrease effect on hypoglycemia; sulphanylureas, sitagliptin and insulin decrease the incidence of treatment discontinuation most; exe_lar and dulaglutide had the highest impact on glycemic level among 13 treatments.

Conclusions

Among 13 treatments, GLP-1 RAs had a significant reduction with glycemic level but a slight increase effect on hypoglycemia and treatment discontinuation. While albiglutide had the best decrease effect on hypoglycemia and treatment discontinuation among all GLP-1 RAs. However, further evidence is necessary for more conclusive inferences on mechanisms underlying the rise in hypoglycemia.

Patient preference and tolerability of a DPP-4 inhibitor versus a GLP-1 analog in patients with type 2 diabetes mellitus inadequately controlled with metformin: a 24-week, randomized, multicenter, crossover study

OBJECTIVE

The present study aimed to assess the patient preference and tolerability of oral dipeptidyl peptidase-4 inhibitor (vildagliptin) versus injectable glucagon-like peptide-1 analog (liraglutide) in patients with type 2 diabetes mellitus inadequately controlled with metformin monotherapy.

METHODS

This 24-week, randomized, multicenter, crossover study, patients with type 2 diabetes mellitus inadequately controlled on metformin monotherapy with hemoglobin A1c (HbA1c) ⩾6.5% and ⩽9.0% were randomized in a crossover manner to receive either vildagliptin/metformin single-pill combination (SPC) 50/1000 mg twice daily (n = 32) or 1.2 mg liraglutide as an add-on to metformin (0.6 mg [weeks 0-1] followed by 1.2 mg [weeks 2-12] once daily/1000 mg twice daily) (n = 30) for the first 12 weeks.

RESULTS

Patient preference at week 24 was similar, with 51.7% (n = 31) patients preferring vildagliptin/metformin SPC compared with 48.3% (n = 29) preferring liraglutide as an add-on to metformin therapy (p = 0.449). Post hoc analyses showed that more elderly patients (⩾65 years) preferred vildagliptin (65%; n = 13) over liraglutide (35%; n = 7) therapy. Liraglutide was associated with better improvement in fasting plasma glucose (-21.5 mg/dl versus -3.4 mg/dl) and HbA1c (-0.5% versus -0.3%) levels. Fewer adverse events were reported with vildagliptin/metformin SPC (n = 16) compared with liraglutide as add-on to metformin treatment (n = 46).

CONCLUSIONS

In this pilot study, although both vildagliptin and liraglutide therapies were preferred similarly by the patients and showed effective control of glycemia over 12 weeks, vildagliptin was associated with fewer adverse events and was preferred more by elderly patients.

Dulaglutide: an evidence-based review of its potential in the treatment of type 2 diabetes

Introduction

As the prevalence of type 2 diabetes mellitus (T2DM) is anticipated to continue to rise worldwide, so too are the treatment options also continuing to expand. Current guidelines recommend individualized treatment plans which allow for provider choice and diversity of pharmacotherapeutic regimens. The glucagon-like peptide-1 receptor agonist (GLP-1 RA) class is rapidly expanding, with dulaglutide (Trulicity™) as a once-weekly agent recently approved.

Aims

This article examines the evidence currently available on the efficacy and safety of dulaglutide for use in T2DM.

Evidence review

Dulaglutide has been shown to have similar efficacy and safety to other newer GLP-1 RAs, and better glycemic control than placebo. It lowers glycated hemoglobin (A_1c), fasting and postprandial glucose levels, and promotes weight loss when used as first-, second-, or third-line therapy. It has also been shown to improve β-cell function and provide cardiovascular benefits, such as lower blood pressure and improved lipid levels. Dulaglutide also has a low risk for hypoglycemia and a similar adverse effect profile to other GLP-1 RAs in the class, with transient gastrointestinal problems and potential risk for pancreatitis.

Place in therapy

While long-term data on safety and efficacy are forthcoming, dulaglutide is positioned to be placed at the same level as other GLP-1 RAs in the class: as second-line therapy in addition to diet and exercise in those patients who cannot achieve glycemic control on monotherapy metformin. It may also be useful as first-line therapy instead of metformin.

Conclusion

Dulaglutide is a once-weekly GLP-1 RA approved for the treatment of T2DM that has shown similar efficacy to other agents in this class.

Alogliptin in combination with metformin and pioglitazone for the treatment of type 2 diabetes mellitus

Alogliptin is a selective dipeptidyl peptidase-4 inhibitor recently marketed for once-daily administration in the treatment of type 2 diabetes mellitus (T2DM). Fixed-dose combinations of alogliptin with both metformin and pioglitazone are also commercially available, providing a measure of convenience in addition to an effective mode of delivering combination therapy to improve glycemic control. Alogliptin has been studied clinically as initial therapy in treatment-naïve patients with T2DM and as initial therapy or add-on in combination with other antidiabetic agents. Clinical trial data with alogliptin demonstrate clinical efficacy in terms of glycosylated hemoglobin A1c and fasting plasma glucose reductions when used both as monotherapy and as a component of two- or three-drug combination regimens for the treatment of T2DM. Extensive Phase II and Phase III clinical trial data support the use of alogliptin in combination with metformin and pioglitazone. Glycemic reduction with both combinations is similar to the sum of the respective monotherapies, with adverse event rates similar - or more moderate - than those observed with up-titration of monotherapy or the addition of other antihyperglycemic agents.