Merck takes aim at Sanofi with a Lantus biosimilar of its own

Sanofi ($SNY) and its top-selling Lantus may have bought some time last month with a legal wrench in Eli Lilly's ($LLY) spokes, but now Merck ($MRK) has bulldozed its way into the conversation with plans to kick off late-stage studies for its own knockoff of the blockbuster drug, further complicating an already heated fight.

Under an expanded agreement with Samsung Bioepis, a joint venture between the South Korean giant and Biogen Idec ($BIIB), Merck plans to develop MK-1293, an insulin glargine candidate that, much like Lantus, provides long-acting relief for patients with Types 1 and 2 diabetes. The pair said it plans to get started on Phase III trials for MK-1293 soon, but a Merck spokeswoman declined to provide a more detailed timeline of the drug's development path.

Merck's entré further complicates the battle over Lantus, a drug whose sales grew 20% last year to bring in about $7.8 billion for Sanofi. The French drugmaker's patent doesn't expire until 2015, but the promise of a blockbuster biosimilar has competitors queuing up to take a shot. Eli Lilly appeared to be first in line as it raced to the FDA with its Lantus generic, but Sanofi's January patent infringement suit triggered a 30-month FDA delay that will likely put off Lilly's launch well into 2016. And that could be the break Sanofi needs to polish up Lantus' successor, the promising U300, and pull off a seamless transition.

But if Merck can make its way to market on time for Lantus' patent loss, it'll wipe away Sanofi's previous victory and further dilute the market by the time Lilly makes its way through the regulatory process. Of course, that's assuming Sanofi and its legal team don't set their sights on MK-1293 next; the company didn't respond to a request for comment on Merck's announcement.

For Merck, the effort dovetails with its focus on diabetes as an area for R&D growth, bolstered by a recent $60 million deal with Pfizer ($PFE) on the SGLT2 blocker ertugliflozin and a $430 million discovery tie-up with startup Abide Therapeutics.

As for Samsung and Biogen, the duo's JV has expanded from collaborative development to solo commercialization, looking to launch some rheumatoid arthritis and Crohn's disease biosimilars in Europe. Bioepis' latest deal with Merck follows a 2013 agreement between the two to develop other undisclosed biologic knockoffs.

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