Pfenex eyes a $75M IPO to bankroll its biosimilars

San Diego biotech Pfenex has evolved from helping Big Pharma craft large-molecule therapies to developing biosimilars of its own, and now the company is looking to raise about $74.8 million to cash in on the coming boom in biologic knockoffs.

The company, a spinoff of Dow Chemical, is using its proprietary protein expression technology to develop biosimilars. Its most advance candidate, a copy of Roche's ($RHHBY) Lucentis, is in midstage study with Phase III slated to kick off next year and data expected in 2017, the company said. Behind that, Pfenex is planning to begin Phase I development of a biosimilar of Bayer's Betaseron this year and do the same for a version of Roche's Pegasys in 2015, two programs partnered with Strides Arcolab.

If its IPO works out, Pfenex plans to trade under "PFNX," spending $40 million of its haul on the Lucentis biosimilar and earmarking $5 million for its Betaseron copy, with the rest going toward pipeline work and general expenditures. 

The key for Pfenex, as for all developers of biologic copies, will be establishing bioanalytical similarity for its candidates. PF582, the biotech's take on Lucentis, has so far compared well to its reference therapy, the company said, and, with the FDA's blessing, Pfenex is moving forward with a late-stage and has designs on a cut of the eye drug's $4.3 billion in annual sales.

And Pfenex figures its timing will work out perfectly. The market for biosimilars has steadily grown around the globe, but it's due for a boom over the next few years, according to the biotech. Pfenex estimates that $45 billion of 2010's aggregate biologics sales will be exposed to biosimilars by 2020, as 47 drugs will have come off patent.

"We expect the biologics market to shift toward biosimilars over the coming years, much like generic small-molecule drugs which now account for an estimated 80% of the dispensed prescription small-molecule drug market in the United States," the company said in a regulatory filing.

Pfenex, a 2011 Fierce 15 winner, began as contract partner for drug developers, providing process development services for the likes of Pfizer ($PFE), Merck ($MRK), Bristol-Myers Squibb ($BMY) and Sanofi ($SNY).

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Special Report: FierceBiotech's 2011 Fierce 15 - Pfenex