Diet, exercise, and weight loss can improve glycemic control, but almost all patients with type 2 diabetes require antihyperglycemic drug therapy. Treating to a target A1C of <7% while minimizing hypoglycemia is recommended to prevent microvascular complications of diabetes (retinopathy, nephropathy, and neuropathy). An A1C target of <8% may be appropriate for some older patients.

The FDA has approved Trijardy XR (Boehringer Ingelheim/Lilly), a fixed-dose combination of the sodium-glucose cotransporter 2 (SGLT2) inhibitor empagliflozin, the dipeptidyl peptidase-4 (DPP-4) inhibitor linagliptin, and extended-release metformin, for oral treatment of type 2 diabetes in adults. Empagliflozin and linagliptin have been available in a fixed-dose combination as Glyxambi since 2015, and both have been available in 2-drug combinations with extended-release metformin for years (see Table 1).

Diet, exercise, and weight loss can improve glycemic control, but almost all patients with type 2 diabetes eventually require drug therapy. Treating to a glycated hemoglobin (A1C) concentration of <7% can prevent microvascular complications (retinopathy, nephropathy, and neuropathy), but whether it prevents macrovascular complications and death is unclear. An A1C target of <8% may be appropriate for older patients and those with underlying cardiovascular disease (CVD), a history of severe hypoglycemia, diabetes-related complications, a limited life expectancy, or a long duration of disease.

For many years, the goal of drug therapy for most patients with type 2 diabetes has been to achieve and maintain an A1C of <7%. Achieving that goal can prevent microvascular complications (diabetic retinopathy, nephropathy, neuropathy), but whether it prevents macrovascular complications (myocardial infarction [MI], stroke) has been less clear. The FDA now requires that cardiovascular safety studies be performed for all new drugs for type 2 diabetes.1 Recent findings that some of the newer second-line drugs for type 2 diabetes have cardiovascular benefits have led to new interest in the cardiovascular efficacy and safety of all antidiabetic drugs.

The goal of drug therapy for type 2 diabetes is to achieve and maintain a near-normal glycated hemoglobin (A1C) concentration without inducing hypoglycemia; the target is generally an A1C of ≤7%. Treating to this target has been shown to prevent microvascular complications (retinopathy, nephropathy, and neuropathy), but whether it prevents macrovascular outcomes is unclear. An A1C target of <8% may be appropriate for older patients and those with underlying cardiovascular disease, a history of severe hypoglycemia, diabetes-related complications or comorbidities, or a long duration of disease.

The FDA has approved Jentadueto XR (Boehringer Ingelheim/Lilly), a once-daily extended-release formulation of the dipeptidyl peptidase-4 (DPP-4) inhibitor linagliptin and the biguanide metformin, for oral treatment of type 2 diabetes. Linagliptin and metformin have been available for years in a twice-daily immediate-release combination (Jentadueto). Once-daily extended-release formulations combining metformin with the DPP-4 inhibitors saxagliptin (Kombiglyze XR) and sitagliptin (Janumet XR) are also available.

The FDA has approved Glyxambi (Boehringer Ingelheim/Lilly), a fixed-dose combination of empagliflozin (Jardiance) and linagliptin (Tradjenta), for oral treatment of type 2 diabetes in adults. It is the first combination of a sodium-glucose co-transporter 2 (SGLT2) inhibitor and a dipeptidyl peptidase-4 (DPP-4) inhibitor to be approved in the US.

The goal of drug therapy for type 2 diabetes is to achieve and maintain a near-normal A1C concentration without inducing hypoglycemia; the target is generally an A1C of <7.0%. Treating to this target has been shown to prevent the microvascular complications of retinopathy and nephropathy, but whether it prevents macrovascular outcomes remains unclear. Three large trials found that intensive glucose control did not reduce the incidence of macrovascular events. One of these trials (ACCORD) in >10,000 patients with type 2 diabetes, with or at high-risk for cardiovascular disease, found that treating patients intensively with antihyperglycemic drugs to an A1C target of 6.0% for a mean of 3.7 years did not significantly reduce the incidence of major cardiovascular events (the primary endpoint) and was associated with increased all-cause mortality compared to patients treated to an A1C target of 7.0-7.9%. An A1C target of 7-8% may be prudent in older patients and in those with underlying cardiovascular disease, severe hypoglycemia, or multiple diabetes-related complications or co-morbidities.

The FDA has approved the dipeptidyl peptidase-4 (DPP-4) inhibitor alogliptin (Nesina – Takeda) for treatment of type 2 diabetes. In addition to the single-ingredient product, the FDA also approved fixed-dose combinations of alogliptin/metformin (Kazano) and alogliptin/pioglitazone (Oseni) for the same indication. Alogliptin is the fourth DPP-4 inhibitor to become available in the US. The other three – saxagliptin (Onglyza), sitagliptin (Januvia), and linagliptin (Tradjenta) – are also available in fixed-dose combinations with metformin.

Canagliflozin (kan" a gli floe' zin; Invokana – Janssen), a sodium-glucose co-transporter 2 (SGLT2) inhibitor, has been approved by the FDA for oral treatment of type 2 diabetes.

Most experts agree that lifestyle modifications and metformin (Glucophage, and others) should be used first to treat patients with type 2 diabetes. If metformin alone fails to control hyperglycemia, there is no general agreement on which drug should be added next. A recent article in The Medical Letter offered some support for a sulfonylurea. Three recent trials published in The Lancet favored the long-acting basal insulin glargine, the glucagon-like peptide (GLP-1) analog exenatide, and the dipeptidyl peptidase-4 (DPP-4) inhibitor linagliptin, respectively. Some of the advantages and disadvantages of these and other available agents are listed in Table 1 on the opposite page.

Linagliptin (Tradjenta) and metformin (Glucophage, and others) are now available as a fixed-dose combination (Jentadueto – Boehringer Ingelheim/Lilly) for oral treatment of type 2 diabetes in adults. Metformin is generally the preferred first-line agent for treatment of type 2 diabetes, but most patients eventually require treatment with multiple drugs. Linagliptin is a dipeptidyl peptidase-4 (DDP-4) inhibitor like sitagliptin (Januvia) and saxagliptin (Onglyza). Both sitagliptin and saxagliptin are also available in fixed-dose combinations with metformin.

The development of hyperglycemia in type 2 diabetes results from a combination of metabolic abnormalities that includes insulin resistance, diminished insulin secretion and excess hepatic glucose production. Diet, exercise and weight loss are helpful in improving glucose control, but most patients ultimately require drug therapy.

Linagliptin (Tradjenta – Boehringer Ingelheim/Lilly), a third oral dipeptidyl peptidase-4 (DPP-4) enzyme inhibitor, was recently approved by the FDA for treatment of type 2 diabetes, either alone or in combination with metformin, a sulfonylurea or pioglitazone