Sanofi has fired a salvo at another rival seeking to invade the fortress that is its diabetes treatment Lantus.
On Sept. 16, the French drug company filed a lawsuit against Merck & Co. in the U.S. District Court for the District of Delaware claiming that Merck infringed 10 patents related to Lantus, a long-acting insulin known generically as insulin glargine. The suit followed Merck’s filing of a New Drug Application with the U.S. Food & Drug Administration for a biosimilar version of the Sanofi drug. That application challenges all 10 of the patents.
Lantus is Sanofi’s biggest selling product, racking up sales last year of $7.1 billion globally and $4.5 billion in the U.S. It’s also the world’s number one selling insulin brand.
Merck developed its follow-on version of Lantus through a biosimilars partnership it established in 2013 with the South Korean firm Samsung Bioepis. FDA approval would mark Merck’s entry into the insulin field.
Sanofi’s U.S. compound patent on Lantus expired in February 2015, but the company maintains other patents on the drug’s formulation and devices that deliver it. Two of the patents at issue relate to preparations with improved stability; the other eight are on delivery pens. Merck says it is confident that its application does not infringe any patents for Lantus.
Merck is one of at least three companies developing follow-on insulin glargine products. In August 2014, Sanofi filed a lawsuit against Eli Lilly & Co. similarly claiming infringement of patents related to Lantus. Lilly and its partner Boehringer Ingelheim had won tentative FDA approval for their product, Basaglar, that same month.
A little more than a year later, Sanofi and Lilly announced a settlement of the suit in the U.S. in which Lilly agreed not to sell its insulin glargine before Dec. 15, 2016.
Meanwhile, in July, India’s Biocon launched an insulin glargine product in Japan with partner Fujifilm Pharma. Biocon is working with the U.S. generics firm Mylan to enter markets outside of Japan. The two firms have said they plan to submit an insulin application in the U.S. and Europe this year.