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

Insulin Glargine (Lantus) is a new long-acting human insulin analog approved by the FDA for treatment of both type 1 and type 2 diabetes. Synthesized by recombinant DNA technology, it differs from human insulin at position 21 in the A-chain where asparagine is replaced by glycine and at the C-terminus of the B-chain where two arginines are added.

Insulin detemir (Levemir - Novo Nordisk) is the second long-acting basal insulin analog to be marketed in the US for treatment of both type 1 and type 2 diabetes. Detemir differs from human insulin by the elimination of the amino acid threonine in position B30 and the addition of a 14-carbon fatty acid chain at position B29. Insulin glargine (Lantus), the first long-acting insulin analog, has been available since 2001 and is usually given once daily.1 NPH insulin is an intermediate-acting basal insulin given twice daily. Basal insulins are usually combined with prandial doses of a rapid-acting...

View the Expanded Table: Some Available Insulins

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.

The FDA has approved Toujeo (Sanofi), a more concentrated form of insulin glargine containing 300 IU/mL compared to the 100 IU/mL in Lantus (Sanofi). Lantus is nearing the end of its patent protection in the US, and biosimilars are expected to become available.

The NovolinPen (Squibb - Novo) is a device that uses prefilled cartridges to inject semisynthetic human insulin (Medical Letter, 25:63, 1983). Three formulations are available: regular insulin (Novolin R PenFill), NPH insulin isophane (Novolin N PenFill) and a mixture of 70% NPH and 30% regular (Novolin 70/30 PenFill). The NovolinPen is advertised as more accurate, more convenient and less expensive than conventional syringes and needles. The same device is marketed in Canada as the Novolin-Pen II (Connaught Novo). (An earlier device is also available as the Novolin-Pen in Canada and the...

Lispro insulin (Humalog - Lilly), a synthetic insulin analog, has been approved for marketing by the US Food and Drug Administration. Prepared by recombinant DNA methods using E. coli, lispro differs from human insulin in having lysine and proline at positions 28 and 29 on the beta-chain, reversed from their natural position. The new drug has biologic effects similar to unmodified insulin, but is absorbed more rapidly after subcutaneous injection.

Insulin aspart (Novolog - Novo Nordisk) is the second rapid-acting insulin analog to be approved by the FDA. The first was insulin lispro (Humalog). Insulin aspart differs from human insulin by substitution of aspartic acid for proline in position 28 on the beta-chain.

Three rapid-acting insulin analogs are currently available: insulin lispro, insulin aspart and insulin glulisine. 1-3 All three are approved for use in both type 1 and type 2 diabetes, either by subcutaneous injection, insulin pump or intravenous administration. All three cost more than regular insulin.