Insulin is a standard of care for the treatment of diabetes and accounts for a large amount of sales in the diabetic drug therapy space. There is often confusion on when an insulin product can be substituted by a pharmacist. Unbranded insulin products are packaged and marketed without a brand-name under the same Biologics License Application as the brand-name product and are considered equivalent and interchangeable. This includes Novolog®/ Insulin Aspart (unbranded), Humalog®/ Insulin Lispro (unbranded), and Semglee (yfgn)®/Insulin Glargine (yfgn) (unbranded).
In the short acting insulin space, Admelog is a brand copy of Insulin Lispro and is not interchangeable with Humalog® or Insulin Lispro. In the long acting insulin space, Lantus is a brand copy of Insulin Glargine but is considered interchangeable with Semglee and Insulin Glargine (yfgn). Basaglar (insulin glargine) is a long acting insulin that is not considered interchangeable with other insulin glargine products. Pharmacists will have to continue to pay attention to formularies, as this class is often impacted by manufacturer discounts and, although an insulin may be interchangeable, it may not be a covered or preferred formulary option for the patient.
The Purple Book database contains information on all FDA-licensed (approved) biological products regulated by the Center for Drug Evaluation and Research (CDER), including licensed biosimilar and interchangeable products, and their reference products. The Purple Book also contains information about all FDA-licensed allergenic, cellular and gene therapy, hematologic, and vaccine products regulated by the Center for Biologics Evaluation and Research (CBER). https://purplebooksearch.fda.gov/