Astra sues as more firms threaten Crestor

By Ben Hirschler

LONDON (Reuters) - AstraZeneca (AZN.L) has filed patent infringement actions in the United States against seven generic drugmakers aiming to sell generic versions of its blockbuster cholesterol pill Crestor, it said on Wednesday.

Britain's second-biggest drugs group first announced last month it faced a generic challenge from Cobalt Pharmaceuticals. But since then it has received similar challenges from another eight generic drug manufacturers.

The speed at which rivals have joined the fray highlights the intense pressure on makers of branded pharmaceuticals as generic companies race to find loopholes in their patent protection.

The challenge to Crestor represents a further blow for AstraZeneca, which is already fighting generic threats to its two biggest revenue generators, Nexium for stomach ulcers and the anti-psychotic drug Seroquel.

AstraZeneca shares were 1.3 percent lower at 22.69 pounds by 0835 GMT.

The active ingredient in Crestor, which had worldwide sales of $691 million (338.2 million pounds) in the third quarter, is covered by a key patent that is valid until January 2016.

Generic drugmakers aim to get their copycat versions to market well before then, although it will not happen overnight.

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