AstraZeneca asthma drug faces U.S. patent crunch

LONDON, Sept 22 (Reuters) - AstraZeneca's (AZN.L) asthma drug Pulmicort could lose U.S. patent protection as early as Tuesday if a court backs generic challenger Teva Pharmaceutical Industries (TEVA.O). A summary judgment hearing is scheduled for Sept. 23. If Teva wins there will be no need for the case to go to full trial, potentially paving the way for a generic launch in the second half of the year, some industry analysts believe.

However, the Israeli-based company would not be able to put its version of the medicine on sale immediately, since it has yet to win U.S. Food and Drug Administration approval -- but this regulatory green light could come at any time.

At stake are some $900 million of annual sales. Full-year U.S. sales for Pulmicort in 2007 totalled $964 million and about 90 percent of this was accounted for by Pulmicort Respules, the form of the drug being disputed in the case.

Pulmicort Respules is a suspension of the active ingredient budesonide, which is designed for use with a nebuliser.

The Anglo-Swedish drugmaker has had a successful run in various patent battles this year, after seeing off a challenge to its blockbuster schizophrenia drug Seroquel and settling a case over its top-selling acid reflux medicine Nexium.

But industry analysts say it has a lower chance of winning the Pulmicort battle because the product is only covered by patents describing its method of use rather than its composition.

AstraZeneca first sued Ivax Pharmaceuticals -- now part of Teva -- for infringing patents covering Pulmicort Respules in October 2005 in the U.S. District Court for the District of New Jersey. (Reporting by Ben Hirschler; editing by Andy Bruce)