Mylan NV said the U.S. Patent and Trademark Appeal Board initiated inter partes review proceedings on two patents owned by France-based Sanofi for its diabetes drug Lantus.
The inter partes review is a trial proceeding conducted to review the patentability of claims of an issued patent.
Lantus, or insulin glargine, is a long-acting basal insulin analogue, used to help control the blood sugar level of patients with diabetes.
The U.S. Food and Drug Administration is reviewing a new drug application filed by Mylan for insulin glargine in vial and pen dosage forms.
Previously, Sanofi sued Mylan in a New Jersey court alleging infringement of 18 patents related to Lantus and Lantus SoloStar.
Sanofi has also filed a lawsuit against Merck & Co. Inc. for infringing on two of Lantus patents, after the U.S. drugmaker submitted a new drug application for an insulin glargine vial drug product.
Eli Lilly and Co. and Boehringer Ingelheim Pharmaceuticals Inc. already market an insulin glargine injection under the name Basaglar, which has an identical amino acid sequence to Lantus.
Lilly and Sanofi have signed a patent settlement agreement that allowed Basaglar to be available in the U.S. in 2016.