The reissuance of a drug patent for Barr Pharmaceuticals' Seasonale might trigger an infringement lawsuit to block sales of the generic extended-cycle oral contraceptive launched by Watson Pharmaceuticals late last year, according to Barr.
"The reissued patent confirms our position that we have the exclusive right to market Seasonale," Barr President and CEO Bruce Downey said.
Barr received a notice of allowance April 9 from U.S. patent authorities regarding its application for reissuance of the '032 patent covering Seasonale (ethinyl estradiol/levonorgestrel) tablets in 0.03- and 0.15-mg strengths. The patent expires in June 2017.
The request came after Watson Pharmaceuticals filed a Paragraph IV abbreviated new drug application seeking FDA approval to market generic Seasonale tablets and challenging the validity and enforceability of the '032 patent.
Barr did not file patent litigation with respect to Watson's challenge.
"[We] amended the claims to address the patent examiner's concerns regarding the patent. We believe that the claims allowed in the reissue application cover the Seasonale product," Barr's Senior Vice President of Corporate Communications Carol Cox said.