Shares of Lannett Co. Inc. /zigman2/quotes/205623272/composite LCI +0.57% gained 7.3% in premarket trading on Wednesday after the company said it received feedback from the Food and Drug Administration about the ongoing development of a biosimilar version of insulin glargine. This type of long-acting insulin is considered a biologic and was initially developed by Sanofi /zigman2/quotes/201967021/composite SNY +1.55% under the brand name Lantus. Lannett said it submitted the clinical-trial protocol to the FDA in November and has since updated it with the regulator's feedback. The company plans to file an investigational new drug application sometime in 2021, with a goal to eventually launch the product in the market in 2023. Lannett's stock is down 15.3% over the past 12 months, while the S&p 500 /zigman2/quotes/210599714/realtime SPX -0.81% has gained 41.1%.