UPDATED: Baxter, Momenta team up in potential $452M biosimilars deal

Drugmakers and biotech groups continue to partner up in the biosimilars game. With plans to develop up to 6 knockoffs of biologic drugs, Baxter International ($BAX) has agreed to pay Momenta Pharmaceuticals ($MNTA) $33 million in cash and potentially more than $419 million in milestone payments and other fees, according to a representative for Momenta.

Baxter has tapped Momenta, which specializes in making copycat versions of complex drugs, for its expertise in analytics and characterizing biologics, as well as its process development capabilities, according to the companies' release. For its part, Baxter brings to the alliance its strengths in clinical development, manufacturing and commercialization. Biosimilars are generic versions of branded biologics, but the complex structures of biologics present technical challenges to replicating them, making the biosimilars game potentially risker than copying small molecule drugs.

Cambridge, MA-based Momenta has a track record of making difficult-to-copy drugs and has already won FDA approval of a generic version of the clot-buster Lovenox, which is made of thousands of sugar chains. The company says its program focused on biosimilars, or follow-on biologics, stretches the use of its technology for analyzing complex sugars to aid in the development of drugs made of proteins and sugars, or glycoproteins. That said, Baxter and Momenta didn't reveal the specific drugs they plan to develop in their alliance in today's release.

"Baxter's global footprint and extensive development, manufacturing and commercial expertise are exactly what we need to succeed in building a leading follow-on biologics business," Momenta CEO Craig Wheeler said in a statement. Baxter and Momenta plan to close their alliance deal in the first quarter of 2012.

Biosimilar development alliances have been popular this month. First Biogen Idec ($BIIB) and a unit of Samsung announced Dec. 6 a $300 million pact to bring knockoff versions of branded biologics to market, and then Amgen ($AMGN) and Watson Pharmaceuticals ($WPI) revealed plans to develop copycat versions of antibody drugs against cancer on Monday, with Watson agreeing to invest up to $400 million into the effort.

At least in the Amgen-Watson deal, Watson executives said the tie-up would reduce the risks that both companies face in entering the biosimilars business. In the U.S., regulators have yet to provide clear clinical-development requirements for biosimilars.

- here's Momenta and Baxter's release

Correction: This story was updated and corrected to say that potential milestones and payments in the deal total more than $419 million, not more than $470 million, the erroneous sum that a representative of Momenta gave to FierceBiotech Thursday afternoon. We regret the error. Here's a link to the company's SEC filing on the deal.