Indian generic firm sun Pharma has settled a patent infringement lawsuit Alzheimer’s medication adamantane (Namenda) with Forest Laboratories.
Forest Labs has been suing several generic companies, including firms from India, alleging that their abbreviated new drug applications (ANDA) under Para IV were infringing its patent on adamantane (Namenda).
The District of Delaware, US has signed off on a stipulation and order resolving the patent dispute between Sun India Pharmaceuticals and Forest Laboratories, Inc. over alleged infringement of U.S. Patent No. 5,061,703 (’703).
US Patent ’709 owned by Forest Labs and assigned to Germany-based Merz Pharma GmbH & Co. KGaA, covers formulations of adamantane derivatives that were manufactured and marketed as Namenda.
Forest has licensed the ’703 patent from Merz.
Forest has no other patents for Namenda listed in US FDA Orange Book.
Sun Pharma, which has been denying that the company had violated Forest’s patent ’703 through filing ANDA to market a generic version of adamantane (Namenda), has retreated from this position in the stipulation.
Sun Pharma has admitted in the stipulation that the company’s filing of generic application for adamantane (Namenda) with US FDA constituted a “technical act of infringement,” reports said.
In addition, Sun Pharma agreed that it will not market or manufacture 5-milligram or 10-milligram tablets during the life of the ’703 patent unless all asserted claims of the patent have been found to be invalid.
Forest’s ’703 patent on adamantane (Namenda) is set to expire in April 2010.
Forest said it also has applied for a patent extension that would prolong the life of the patent through September 2013.
The District Court’s order dismissed without prejudice all claims and counterclaims in the case.
In January 2008, Forest Laboratories and its partner Merz Pharma filed several lawsuits against generic firms including Lupin Ltd, Orchid Chemicals & Pharmaceuticals Ltd and Wockhardt Ltd, Cobalt Laboratories, Teva Pharmaceuticals, Upsher-Smith Laboratories, Ranbaxy, Mylan and Barr Laboratories in the U.S. District Court for the District of Delaware as these companies tried to obtain marketing approval for adamantane (Namenda).
Alzheimer’s and dementia drug Namenda posted sales of $738 million for the 12 months leading up to Sept. 30, 2007.
Namenda helped boost Forest’s fiscal third-quarter net by 21 percent to $301 million, or 96 cents a share. Revenue was up by 12 percent to $998 million in the fiscal year 2008.
In July, Sun Parma and its US subsidiary Caraco Pharmaceutical Laboratories entered into agreements with Forest Laboratories and H. Lundbeck A/S to settle the legal proceedings related to escitalopram oxalate (Lexapro) tablets out of court.
As per the settlement, Sun Pharma will license to Lundbeck on a worldwide basis certain patent applications related to the synthesis of escitalopram and citalopram in exchange for an upfront payment and, if the technology is used, royalties on sales.
Caraco filed an Abbreviated New Drug Application (ANDA No. 78-219) with the FDA seeking generic approval for 5, 10, and 20 mg tablets of escitalopram oxalate in March 2006.
Forest laboratories and Lundbeck initiated legal action against Caraco on July 10, 2006 by filing a patent infringement lawsuit at United States District Court Eastern District Of Michigan Southern Division alleging that Caraco’s ANDA products would infringe their ‘712 patent.
Forest and Lundbeck, who listed the ‘712, ‘941, and ‘069 patents in the Orange Book, alleged that an infringement suit could reasonably be asserted against any generic ANDA applicant, including Caraco, that attempts to seek approval for, and market, a generic version of Lexapro before the expiration of the ‘712, ‘941, and ‘069 patents.
On February 20, 2007, Caraco filed a declaratory judgment action against Forest and Lundbeck seeking a declaration that Caraco’s ANDA Products will not infringe the ‘941 patent.
The companies resolved the dispute after reaching an agreement out of court.
Apart from licencing escitalopram rights to Forest and Lundbeck, the settlements require Forest provide licenses to Caraco for any patents related to Lexapro and with respect to the marketing of Caraco’s generic version of the product as of the date that any third party generic that has received final approval from the FDA enters the market other than an authorized generic or the first filer with Hatch-Waxman related exclusivity.
Caraco will take over the commercialization and sale of several products from Forest’s Inwood business. Caraco will pay Forest an undisclosed advance against royalties and royalties on net sales of these products.
Forest was expected reimburse Caraco for a portion of their costs related to this litigation.