An oral formulation of the glucagon-like peptide-1 (GLP-1) receptor agonist semaglutide (Rybelsus – Novo Nordisk) has been approved by the FDA for once-daily treatment of type 2 diabetes in adults. Semaglutide, which has been available in a subcutaneously-injected formulation (Ozempic) since 2017, is the first GLP-1 receptor agonist to become available for oral administration; the 4 other GLP-1 receptor agonists currently available in the US are administered by subcutaneous (SC) injection.

Troglitazone (Rezulin - Parke-Davis), the first of a new class of thiazolidinedione derivatives ('glitazones') for diabetes, has been marketed for oral treatment of noninsulin- dependent diabetes mellitus (NIDDM) in patients who take more than 30 units of insulin daily and still have a glycosylated hemoglobin concentration (HbA1c) of 8.5% or higher.

Exenatide injection (Byetta - Amylin/Lilly), a synthetic peptide that stimulates release of insulin from pancreatic beta cells, has been approved by the FDA as adjunctive therapy for patients with type 2 diabetes who have not achieved optimal glycemic control on metformin (Glucophage, and others), a sulfonylurea, such as glyburide (DiaBeta, and others), or both. Exenatide is not indicated for use with insulin.

Pioglitazone is the third thiazolidinedione ("glitazone") to be marketed in the USA for treatment of type 2 diabetes. Thiazolidinediones decrease resistance to insulin.

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 removed prescribing and dispensing restrictions placed on rosiglitazone (Avandia, and others) in 2010 because of concerns about its cardiovascular safety.1 The removal of restrictions was based on the results of an independent reevaluation of the RECORD trial, which found no significant difference between rosiglitazone and metformin/sulfonylurea in the risk of cardiovascular (or unknown cause) death, myocardial infarction, or stroke.21. FDA Drug Safety Communication: FDA requires removal of some prescribing and dispensing restrictions for rosiglitazone-containing diabetes...

Sitagliptin phosphate (Januvia - Merck) is the first dipeptidyl-peptidase-4 (DPP-4) inhibitor to be marketed for treatment of type 2 diabetes. It has been approved by the FDA for oral use as monotherapy or in combination with metformin (Glucophage, and others), pioglitazone (Actos) or rosiglitazone (Avandia).

The thiazolidinediones rosiglitazone (Avandia) and pioglitazone (Actos) are peripheral insulin sensitizing agents used to treat hyperglycemia in patients with type 2 diabetes; one or the other is often used as a second or third agent with metformin (Glucophage, and others) and/or a sulfonylurea such as glimepiride (Amaryl, and others). A recent report suggested that rosiglitazone may increase the incidence of myocardial infarction (MI) and cardiovascular mortality.

Glimepiride (Amaryl - Hoechst Marion Roussel), a new sulfonylurea similar to glyburide and glipizide (Medical Letter, 26:79, 1984), was recently marketed for treatment of patients with non-insulin-dependent diabetes mellitus (NIDDM) not controlled by diet and exercise. The new drug is the first sulfonylurea approved by the US Food and Drug Administration (FDA) for use concurrently with insulin.

Acarbose (Precose -Bayer), an oral alpha-glucosidase inhibitor that has been available in Europe for several years, was recently approved by the US Food and Drug Administration (FDA) for treatment of non-insulin-dependent diabetes mellitus (NIDDM).