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 tirzepatide (Mounjaro – Lilly), a peptide hormone with activity at both glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) receptors, to improve glycemic control in adults with type 2 diabetes. Tirzepatide, which is injected subcutaneously once weekly, is the first dual GIP/GLP-1 receptor agonist to become available in the US. Selective GIP receptor agonists are not available in the US; GLP-1 receptor agonists have been available for years.

Insulin glargine-yfgn (Semglee – Viatris), a follow-on insulin glargine product, has now received interchangeability status with the reference product Lantus from the FDA. It is the first biosimilar insulin product to receive this designation in the US. Now a pharmacist can substitute Semglee for Lantus as a lower-cost alternative without permission from the prescriber.

The FDA has approved Semglee (Mylan), an insulin glargine product similar to Lantus, for treatment of type 1 diabetes in children and adults and type 2 diabetes in adults. Semglee is the second "follow-on" insulin glargine product to become available in the US; Basaglar, which is also similar to Lantus, was the first. Lantus is a recombinant analog of human insulin that forms microprecipitates in subcutaneous tissue, prolonging its duration of action to a mean of about 24 hours with no pronounced peak effect.

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.

The goal of drug therapy for type 2 diabetes is to achieve and maintain a near-normal glycated hemoglobin (A1C) concentration without inducing hypoglycemia; for most patients, the target A1C is <7%. Metformin is the preferred first-line treatment, but most patients with type 2 diabetes eventually require multidrug therapy and/or insulin to achieve glycemic control.

View the Expanded Table: Some Available Insulins

The FDA has approved semaglutide (Ozempic – Novo Nordisk), a long-acting injectable GLP-1 (glucagon-like peptide-1) receptor agonist, for once-weekly treatment of adults with type 2 diabetes. It is the sixth GLP-1 receptor agonist to be approved in the US.

The FDA has approved Fiasp (Novo Nordisk), a new formulation of insulin aspart, to improve glycemic control in adults with diabetes. Fiasp is described by the manufacturer as faster-acting than conventional insulin aspart (Novolog).

The FDA has approved Xultophy 100/3.6 (Novo Nordisk), a fixed-ratio combination of insulin degludec and the GLP-1 (glucagon-like peptide-1) receptor agonist liraglutide, for once-daily treatment of adults with type 2 diabetes inadequately controlled on basal insulin (<50 units daily) or liraglutide (≤1.8 mg daily).

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.

Per capita spending on prescription drugs in the US is higher than in other industrialized nations, including Canada.

The FDA has approved lixisenatide (Sanofi), a short-acting injectable GLP-1 (glucagon-like peptide-1) receptor agonist, for once-daily treatment of adults with type 2 diabetes, both alone (Adlyxin) and in a fixed-ratio combination with insulin glargine (Soliqua 100/33). Lixisenatide has been available since 2013 in many other countries as Lyxumia. It is the fifth GLP-1 receptor agonist to be approved in the US.

The FDA has approved infliximab-dyyb (Inflectra – Pfizer; marketed as Remsima in some countries), as a biosimilar of the TNF inhibitor infliximab (Remicade). Infliximab-dyyb was approved in the European Union (EU) in 2013 and in Canada in 2014. It is the second biosimilar to be approved by the FDA. Filgastrim-sndz (Zarxio), a recombinant human granulocyte colony-stimulating factor, was the first.

The FDA has approved Basaglar (Lilly/Boehringer Ingelheim), a "follow-on" 100 units/mL insulin glargine product similar to Lantus (Sanofi), which recently went off patent. A 300 units/mL formulation of insulin glargine (Toujeo) was approved in 2015.

The FDA has approved insulin degludec (Tresiba – Novo Nordisk) for treatment of adults with type 1 or type 2 diabetes. Insulin degludec is the third long-acting human insulin analog to be approved by the FDA; insulin detemir (Levemir) and insulin glargine (Lantus, Toujeo) were approved earlier.

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.

Several large European observational studies published on-line this summer have raised questions about whether use of insulin glargine increases the risk of cancer.

The development of hyperglycemia in type 2 diabetes results from a combination of metabolic abnormalities including 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.

Insulin glulisine (Apidra - Sanofi Aventis) is the third rapid-acting insulin analog to be marketed in the US, following insulin lispro (Humalog) and insulin aspart (Novolog). All three have a more rapid onset and shorter duration of action than regular human insulin. Rapid-acting insulin analogs are generally taken immediately before meals and are usually combined with a long-acting basal insulin.

The development of hyperglycemia in type 2 diabetes results from a combination of metabolic abnormalities including insulin resistance, excess hepatic glucose production and diminished insulin secretion. In many patients, diet and regular exercise can improve glucose control. Most drugs currently available for management of type 2 diabetes increase insulin supply (sulfonylureas, other secretagogues and insulin itself), decrease insulin resistance (thiazolidinediones) or improve the effectiveness of insulin (biguanides). Alpha-glucosidase inhibitors reduce the rate of glucose absorption. Newer agents such as pramlintide (Symlin) and exenatide (Byetta) have multiple effects to increase satiety and reduce postprandial hyperglycemia.

The development of hyperglycemia in type 2 diabetes results from a combination of metabolic abnormalities including insulin resistance, excess hepatic glucose production and diminished insulin secretion. Most drugs currently available for management of type 2 diabetes fall into 2 categories: those that increase insulin supply (sulfonylureas, other secretagogues and insulin itself) and those that decrease insulin resistance or improve its effectiveness (biguanides, thiazolidinediones). Alpha-glucosidase inhibitors reduce the rate of glucose absorption.