* FDA likely to require additional trials
* Shire had expected quick approval process
March 14 (Reuters) - Shire Plc has withdrawn its U.S. Food and Drug application for its rare disease drug Replagal, citing the agency's need for more clinical studies, the company said on Wednesday.
Replagal is an enzyme replacement therapy for Fabry disease, a rare genetic disorder in which fat builds up in the body.
Shire had been supplying the drug to the U.S. market due to manufacturing problems in 2009 that lead to short supplies of Fabrazyme, which is made by Genzyme, now owned by Sanofi SA . Replagal has been on the market in Europe since 2001.
Shire had filed in November for FDA approval for Replagal, "in anticipation of a quick review process," the company said.
Shire said the agency did not express concerns over the product's safety, but will likely require additional controlled trials for approval.
The company said the "likely additional studies would cause a significant delay, and an approval of Replagal for U.S. patients would only be possible in the distant future."