The European Medicines Agency's Committee for Medicinal Products for Human Use (CHMP) on Friday recommended that the European Commission approve Pfizer's (NYSE:PFE) drug Ruxience, a biosimilar to MabThera, which to Roche (OTC:RHHBY) and Biogen (NASDAQ:BIIB) sell in the U.S. as Rituxan.

CHMP's positive opinion was based on a clinical trial, dubbed Reflections B3281006, which compared Ruxience to the branded biologic drug MabThera in patients with a specific type of follicular lymphoma. Both drugs produced similar overall response rates.

Biologics are large-molecule drugs that are produced using living organisms, as opposed to via chemical processes like conventional, small-molecule medications. This difference in how they're manufactured means that while another company may be able to develop a biologic that does essentially the same thing as a previously approved drug, that new version -- the biosimilar -- will not be not quite the same as the original -- thus the "similar" in the name.

Doctor showing a report to a patient in a hospital bed

Image source: Getty Images.

While Pfizer is better known for its branded drugs, the pharmaceutical company has jumped on the biosimilar bandwagon; it has already developed four other oncology biosimilars that are available in Europe. The company sold $911 million worth of biosimilar drugs last year, with those revenues split almost equally between the U.S. and the rest of the world. Pfizer has also gotten a taste of its own medicine on this front: Sales of its anti-inflammatory biologic Enbrel were down 18% in the fourth quarter due to biosimilar competition. When Pfizer hives off its Upjohn generic drug unit later this year, its biosimilars will stay with the branded drug division.

Before Pfizer can start selling Ruxience in the EU, CHMP's positive opinion will need to be finalized by the European Commission. That decision is expected to be handed down in the first half of this year.