Tolerability of saxagliptin in patients with inadequately controlled type 2 diabetes: results from 6 phase III studies

The Use of Saxagliptin in People with Type 2 Diabetes in France: The Diapazon Epidemiological Study

INTRODUCTION

Saxagliptin is a potent, reversible inhibitor of dipeptidyl peptidase-4 that is indicated for the treatment of type 2 diabetes. The DIAPAZON study was a multicenter observational study intended to document the effectiveness, safety and patterns of saxagliptin use in France, including the saxagliptin retention rate, over 2 years of follow-up.

METHODS

A geographically representative sample of 304 French physicians (general practitioners and specialist endocrinologists or diabetologists) recruited 1131 adults with type 2 diabetes into an ambispective cohort; 1033 fulfilled the inclusion criteria. All had started saxagliptin during the previous 6 months or at study inclusion, and follow-up was for 24 ± 3 months after starting saxagliptin.

RESULTS

The mean age of the study population when starting saxagliptin was 61 years, and the mean HbA1c level was 8.0%; 79% had an HbA1c level ≥7%. Prior to starting saxagliptin treatment, most participants (91%) were receiving treatment with oral glucose-lowering drugs alone. The most commonly prescribed regimen at starting saxagliptin (53% of participants) was a combination of saxagliptin and metformin. The overall saxagliptin retention rate at 2 years was 79%, as estimated by the Kaplan-Meier method. The most common reasons for discontinuation were inadequate glycemic control (52%) and intolerance (22%). During the course of the study, the mean HbA1c level decreased to 7.0%, and the percentage of people with HbA1c <7% increased from 21% to 49%. The mean change in body weight was -1.8 kg. A total of 294 hypoglycemic episodes were reported in 70 participants (6.8%) during the follow-up period. Of these, 143 episodes in 41 participants (4.0%) occurred when saxagliptin was used in combination with agents associated with hypoglycemia, such as insulin, sulfonylureas or glinides.

CONCLUSION

Saxagliptin is efficacious and well tolerated in a real-world practice setting, with almost 80% of participants remaining on treatment after 2 years.

FUNDING

AstraZeneca, France.

Targeting orphan G protein-coupled receptors for the treatment of diabetes and its complications: C-peptide and GPR146

G protein-coupled receptors (GPCRs) are the most abundant receptor family encoded by the human genome and are the targets of a high percentage of drugs currently in use or in clinical trials for the treatment of diseases such as diabetes and its associated complications. Thus, orphan GPCRs, for which the ligand is unknown, represent an important untapped source of therapeutic potential for the treatment of many diseases. We have identified the previously orphan GPCR, GPR146, as the putative receptor of proinsulin C-peptide, which may prove to be an effective treatment for diabetes-associated complications. For example, we have found a potential role of C-peptide and GPR146 in regulating the function of the retinal pigment epithelium, a monolayer of cells in the retina that serves as part of the blood-retinal barrier and is disrupted in diabetic macular oedema. However, C-peptide signalling in this cell type appears to depend at least in part on extracellular glucose concentration and its interaction with insulin. In this review, we discuss the therapeutic potential of orphan GPCRs with a special focus on C-peptide and GPR146, including past and current strategies used to 'deorphanize' this diverse family of receptors, past successes and the inherent difficulties of this process.

Saxagliptin for the treatment of diabetes - a focus on safety

INTRODUCTION

The safety of agents used to treat type 2 diabetes (T2D), a chronic disease requiring life-long intervention, is of particular interest. Saxagliptin is a potent and selective DPP-4 inhibitor that has emerged as a therapeutic option for T2D.

AREAS COVERED

Its safety was assessed in a development program of 20 phase 2/3 randomized clinical trials and in SAVOR-TIMI 53 trial that evaluated the cardiovascular outcomes. In order to capture any further safety signals, mainly in the long-term, a post-marketing safety surveillance is ongoing. This paper discusses the tolerability and safety profile of the agent, including cardiovascular, renal, pancreatic, hepatic and bone adverse events.

EXPERT OPINION

Saxagliptin is a safe therapeutic option for patients with T2D, with low risk of hypoglycemia and good tolerability. It demonstrated cardiovascular safety (including in patients with pre-existing cardiovascular disease and/or HF) and safety with respect to all-cause mortality and adverse events of special interest. In SAVOR-TIMI53, saxagliptin was associated with an unexpected increased risk of HF hospitalization, mainly in the first 12 months; a mechanistic explanation for this has not been found. Further research needs to elucidate the effect of antidiabetic drugs on the heart, by including biomarkers and echocardiographic sub-studies within large outcome trials.

Pharmacokinetic, pharmacodynamic and clinical evaluation of saxagliptin in type 2 diabetes

INTRODUCTION

Dipeptide peptidase-4 (DPP-4) inhibitors such as saxagliptin are established and efficacious oral therapies in the management of type 2 diabetes. These agents have the potential to confer significant benefits in glycemic control without the risk of weight gain and hypoglycemia, which may be associated with other medications used to treat type 2 diabetes.

AREAS COVERED

This review examines the pharmacokinetics, efficacy and tolerability of saxagliptin for the management of type 2 diabetes.

EXPERT OPINION

Saxagliptin is routinely used in the management of type 2 diabetes as monotherapy, and in combination with other oral agents and insulin. Robust clinical trials have shown consistent improvements in glycated hemoglobin, fasting and postprandial glucose levels, with few adverse effects. The agent is well tolerated with low rates of hypoglycemia in the absence of insulin or sulphonylurea therapy.

Safety of dipeptidyl peptidase-4 inhibitors for treating type 2 diabetes

INTRODUCTION

Dipeptidyl peptidase-4 (DPP-4) inhibitors (gliptins) occupy a growing place in the armamentarium of drugs used for the management of hyperglycemia in type 2 diabetes, although some safety concerns have been raised in recent years.

AREAS COVERED

An updated review providing an analysis of available safety data (meta-analyses, randomized controlled trials, observational cohort and case-control studies and pharmacovigilance reports) with five commercialized DPP-4 inhibitors (sitagliptin, vildagliptin, saxagliptin, alogliptin, linagliptin). A special focus is given to overall safety profile; pancreatic adverse events (AEs) (acute pancreatitis, pancreatic cancer); overall cardiovascular safety (myocardial infarction and stroke); congestive heart failure concern and finally, safety in special populations (elderly, renal impairment).

EXPERT OPINION

The good tolerance/safety profile of DPP-4 inhibitors has been largely confirmed, including in more fragile populations (elderly, renal impairment) with almost no increased risk of infection or gastrointestinal AEs, no weight gain and a minimal risk of hypoglycemia. Although an increased risk of acute pancreatitis and pancreatic cancer was suspected, the complete set of available data appears reassuring so far. Cardiovascular safety of DPP-4 inhibitors has been proven but an unexpected increased risk of heart failure has been reported which should be confirmed in ongoing trials and better understood. Further postmarketing surveillance is recommended.