Warner Chilcott gone to court in the US to block Watson Pharmaceutical's attempt to market a generic version of its contraceptive Lo Loestrin Fe.
Ireland-based pharma firm Warner Chilcott filed a lawsuit in the New Jersey District Court following Waton's filing of an abbreviated new drug application with the US Food and Drug Administration (FDA) ahead of the drug's patent expiration.
Warner Chilcott told Bloomberg the Watson version would infringe two patents and it is seeking a court order to prevent sales until the separate patents expire in July 2014 and February 2029.
If the court does not rule in favour of Watson, the FDA would be prevented from granting a final approval for Waton's ANDA for 30 months.
Lo Loestrin Fe (norethindrone acetate and ethinyl estradiol), a loss dose contraceptive, had US sales of $86m for the 12 months ending March 31, 2012.
Warner Chilcott has been involved in previous lawsuits regarding its franchise of Loestrin contraceptives.
In 2010, the company settled with Lupin Pharmaceuticals over its bid to launch generic versions of Loestrin 24 Fe and Femcon Fe, with Lupin agreeing to hold off on launching Loestrin 24 Fe and being granted a nono-exclusive licence to sell Femcom Fe.
Both Watson and Warner Chilcott are also look set to undergo several changes over the next few years, with the latter announcing that it was in talks with potential buyers in May 2012.
Meanwhile, Watson is in the middle of taking over Iceland-headquartered Actavis in a €4.3bn deal, which will "dramatically enhance our commercial position on a global basis, and brings complementary products and capabilities in the US”, according to its CEO Paul Bisaro.