Explanations for Shire plc's decision to withdraw its BLA for Replagal agalsidase alfa two weeks ahead of an advisory committee meeting boil down to a classic "he said, she said" controversy, with the company and FDA pointing fingers at each other - and Fabry's disease patients caught in the middle.

Shire says it withdrew the BLA because briefing documents prepared for the planned March 27 meeting of FDA's Cardiovascular and Renal Drugs Advisory Committee made clear the agency's approval of the Replagal BLA would be contingent on the company running additional pre-market trials.