Warner Chilcott Limited announced that one of its subsidiaries and Mayne Pharma International Pty Ltd (Mayne), a subsidiary of Hospira, Inc, have filed lawsuits against each of Mutual Pharmaceutical Company, Inc (Mutual), Mylan Pharmaceuticals Inc (Mylan) and Impax Laboratories, Inc (Impax) in the District Court for the District of New Jersey for infringement of Mayne's US Patent No. 6,958,161 (the 161 Patent) which covers Doryx, a tetracycline-class oral antibiotic. Warner Chilcott markets and sells Doryx delayed-release tablets in 150, 100 and 75 mg strengths under a license agreement with Mayne.

The lawsuits are in response to the submission of Abbreviated New Drug Applications (ANDAs) to the US Food and Drug Administration (FDA) by each of Mutual, Mylan and Impax requesting approval to manufacture and sell generic versions of Doryx 100 and 75 mg delayed-release tablets prior to the expiration in 2022 of the '161 Patent. Warner Chilcott and Mayne intend to vigorously defend the '161 Patent and pursue their legal rights.

Warner Chilcott is a specialty pharmaceutical company focused on developing, manufacturing, marketing and selling branded prescription pharmaceutical products in women's healthcare and dermatology in the U.S. WCRX-G.