UPDATE 1-Teva wins EU approval for biosimilar Neupogen

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LONDON, Sept 16 (Reuters) - European authorities have approved Teva Pharmaceutical Industries' TEVA.O biosimilar version of Neupogen, Amgen's (AMGN.O) best-selling treatment for neutropenia, the Israeli generic drugmaker said on Tuesday.

The approval marks a further opening of the European Union biotech drug market to generic copies.

The move had been expected, after Teva's product, TevaGrastim, won a positive opinion from the European Medicines Agency in February.

Teva said it would begin marketing the medicine throughout Europe in 2009, following the final clearance from the European Commission.

Neupogen, used to boost white blood cells in patients on chemotherapy, has annual sales of about $300 million in the European Union, according to data compiled by IMS Health, Teva said.

Neupogen is a biotechnology medicine and, as such, contains proteins that are much more difficult to replicate than conventional small-chemical pharmaceutical compounds.

Because of their complexity, regulators have been wary about approving generic versions of biotech drugs, although Europe has been more advanced in giving a green light than the United States.

European officials also approved biosimilar forms of EPO, an anaemia drug, and human growth hormone.

For generic drugmakers, biotech drugs represent an enticing market opportunity -- especially as prices for such products are expected to be only 25 to 40 percent below those of original brands, according to the European Generic Medicines Association.

The price of conventional easy-to-make generic drugs can quickly fall to a 90 percent discount to the original. (Reporting by Ben Hirschler; editing by Simon Jessop)