Sitagliptin and other ‘gliptins’ - why prescribe them?

Introduction In 2008, the Federal Drug Administration (FDA) required all new glucose-lowering therapies to show cardiovascular safety, and this applies to the dipeptidyl peptidase (DPP)-4 inhibitors (‘gliptins’). At present, there is contradictory evidence on whether the gliptins increase hospitalizations for heart failure. Areas covered This is an evaluation of the Trial Evaluating Cardiovascular Outcomes with Sitagliptin (TECOS) in high risk cardiovascular subjects with type 2 diabetes [1]. TECOS demonstrated non-inferiority for sitagliptin over placebo for the primary outcome, which was cardiovascular death, nonfatal myocardial infarction, nonfatal stroke, or hospitalization for unstable angina. There was no difference in the rate of hospitalization for heart failure between sitagliptin and placebo. Expert Opinion Despite the results of TECOS, debate over the effects of sitagliptin on the rates of hospitalizations for heart failure continues with some recent studies suggesting increased rates. Recently, empagliflozin (an inhibitor of sodium-glucose cotransporter 2) has been shown to reduce cardiovascular outcomes in subjects with type 2 diabetes, including the rates of hospitalization for heart failure. In our opinion, these positive findings with empagliflozin suggest that it should be prescribed in preference to the gliptins, including sitagliptin, unless any positive cardiovascular outcomes are reported for the gliptins.

Inibidores do co-transportador renal de sódio-glicose 2

Projeto de Pós-Graduação/Dissertação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Ciências Farmacêuticas

SGLT inhibitors in management of diabetes

The two main sodium-glucose cotransporters (SGLTs), SGLT1 and SGLT2, provide new therapeutic targets to reduce hyperglycaemia in patients with diabetes. SGLT1 enables the small intestine to absorb glucose and contributes to the reabsorption of glucose filtered by the kidney. SGLT2 is responsible for reabsorption of most of the glucose filtered by the kidney. Inhibitors with varying specificities for these transporters (eg, dapagliflozin, canagliflozin, and empagliflozin) can slow the rate of intestinal glucose absorption and increase the renal elimination of glucose into the urine. Results of randomised clinical trials have shown the blood glucose-lowering efficacy of SGLT inhibitors in type 2 diabetes when administered as monotherapy or in addition to other glucose-lowering therapies including insulin. Increased renal glucose elimination also assists weight loss and could help to reduce blood pressure. Effective SGLT2 inhibition needs adequate glomerular filtration and might increase risk of urinary tract and genital infection, and excessive inhibition of SGLT1 can cause gastro-intestinal symptoms. However, the insulin-independent mechanism of action of SGLT inhibitors seems to offer durable glucose-lowering efficacy with low risk of clinically significant hypoglycaemia at any stage in the natural history of type 2 diabetes. SGLT inhibition might also be considered in conjunction with insulin therapy in type 1 diabetes. © 2013 Elsevier Ltd.

Pharmacotherapies to manage diabesity:an update

Several pharmacotherapies have recently become available for addition to lifestyle measures to assist the management of coexistent type 2 diabetes and obesity. These are mostly administered as add-on to metformin or as alternative therapies if metformin is not appropriate. The sodium–glucose cotransporter 2 inhibitors (dapagliflozin, canagliflozin and empagliflozin) act by eliminating excess glucose in the urine. These agents provide a non-insulin-dependent mechanism to reduce hyperglycaemia and facilitate weight loss without causing frank hypoglycaemia. Their efficacy requires the individual to have adequate renal function. The glucagon-like peptide-1 (GLP-1) receptor agonists (exenatide, liraglutide, lixisenatide, dulaglutide and albiglutide [the last at the pre-launch stage at the time of writing]) are injected subcutaneously. Different members of the class offer different time courses for their onset and duration of action. Each potentiates insulin secretion and reduces glucagon secretion in a glucose-dependent manner to address prandial glycaemic excursions while avoiding interprandial hypoglycaemia. A satiety effect of these agents assists weight reduction, but delayed gastric emptying can cause initial nausea. The dipeptidyl peptidase-4 inhibitor class now comprises sitagliptin, vildagliptin, saxagliptin, linagliptin and alogliptin. These agents offer similar glucose-lowering efficacy without weight gain or hypoglycaemia by boosting the half-life of endogenous incretins, particularly GLP-1. A fixed-ratio injected combination of insulin degludec with liraglutide (IDegLira) has recently been launched and further agents to address hyperglycaemia and assist weight loss are advancing in development.