Dr. Reddy's Laboratories (DRL) has announced that the Company had filed an Abbreviated New Drug Application (ANDA) with the US Food and Drug Administration for Fexofenadine HCl Tablets, equivalent to 30 mg, 60 mg and 180 mg of base, with Paragraph IV certifications on all seven Orange Book patents listed for tablets Allegra of Aventis Pharmaceuticals Inc.

DRL has notified Aventis upon which the latter filed a lawsuit against the Company in the United States District Court for the District of New Jersey alleging patent infringement on six Orange Book patents.

Fexofenadine HCl Tablets are the generic version of Aventis' Allegra tablets. The product is indicated for the relief of symptoms associated with seasonal allergic rhinitis. The brand has annual sales in the United States of approximately $1.35 billion according IMS 2002 audit.