Takeda/Sucampo seek wider use of constipation drug

TOKYO, July 13 (Reuters) - A supplemental new drug application has been filed for a constipation drug sold by Takeda Pharmaceutical Co. Ltd. (4502.T) that could take more market share after Novartis (NOVN.VX) pulled a rival drug from U.S. shelves this year.

Sucampo Pharmaceuticals Inc., the drug's developer, said it had filed with the U.S. Food and Drug Administration for its chronic constipation drug Amitiza to also be used to treat constipation-related irritable bowel syndrome.

Sucampo, which is not listed, and Takeda, Japan's biggest drugmaker, co-market the drug in the United States.

The filing is for a lower strength version of Amitiza, which is known generically as lubiprostone.

Amitiza has gained significant market share -- although Takeda has declined to say how much -- since Novartis was asked to pull its Zelnorm drug after clinical trial data indicated a possible link to heart attacks and strokes.

Swiss authorities have also ordered the withdrawal of Zelnorm for the same reasons.

Zelnorm had total sales of $561 million in 2006, of which $488 million was generated in the United States.

An estimated 58 million Americans have irritable bowel syndrome (IBS), with constipation-related IBS accounting for one-third of these cases.

That compares with around 33 million U.S. sufferers of chronic idiopathic constipation, for which Amitiza is currently approved.

U.S. authorities have said Zelnorm might be able to return on a limited basis but only if a group of patients could be identified for whom the benefits outweighed the risks.