Lundbeck is working to find replacements for its key anti-depressant, Cipralex, which is sold as Lexapro in the United States and Japan, as it comes off patent protection. The company has warned earnings will stall until 2015 due to cheap generic competition, meaning new products are key for future revenue growth.

The application "represents an important step in the evaluation of a potentially new treatment option for this debilitating disease," said Anders Gersel Pedersen, head of research and development at Lundbeck.

Last week, Lundbeck filed for regulatory approval in Europe for vortioxetine, the first filing of a non-copy antidepressant in Europe in five years.

In September 2007, Lundbeck and Takeda formed a strategic alliance for the exclusive co-development and co-commercialization in the United States and Japan of several compounds in Lundbeck's pipeline for the treatment of mood and anxiety disorders.

(Reporting by Mette Fraende; Editing by Matt Driskill)

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