Purepac Challenges Andrx Cardia XT Exclusivity On Reformulation Grounds

A first-to-file ANDA applicant should lose its eligibility for 180-day exclusivity if it makes major changes to the application at a later date, Purepac asserts in a petition to FDA requesting that Andrx be stripped of its exclusivity for generic sustained-release diltiazem, equivalent to Hoechst Marion Roussel's Cardizem CD.