Innovator Shire announced (in a press release Here ) that it has filed a lawsuit in the U.S. District Court of the Southern District of New York against Barr Labs for infringement of following Orange Book listed patents for Lanthanum Carbonate (Fosrenol) Chewable tablets 500mg, 750mg and 1gm:
US5968976 (Expiry: Oct 26, 2018): Which coves a pharmaceutical composition for the treatment of hyperphosphataemia comprising lanthanum carbonate
US7381428 (Expiry: Aug 26, 2024): Which coves a stabilized Lanthanum Carbonate Compositions against substantial decarboxylation to lanthanum hydroxycarbonate before administration by admixing the lanthanum carbonate in an amount of from 13.4-13.9% to 32.2-33.3% by weight of the composition as elemental lanthanum with a monosaccharide or disaccharide in an amount from 20 to 80% by weight of the composition, wherein the monosaccharide or disaccharide is dextrates, mannitol, sorbitol, or a mixture thereof and the amount of the monosaccharide or disaccharide is such that lanthanum hydroxycarbonate is not observed in an x-ray powder diffraction (XRPD) pattern of the lanthanum carbonate composition after it has been exposed to 60 degree C and 95% relative humidity for at least 7 days.
US7465465 (Expiry: Aug 26, 2024): Which coves a lanthanum carbonate pharmaceutical formulation in a chewable tablet, comprising lanthanum carbonate in an amount of from about 200 mg to about 1000 mg elemental lanthanum in the proportion of about 10 to about 40 wt % of the formulation as elemental lanthanum and pharmaceutically acceptable excipients comprising a diluent in an amount from about 40 to about 80 wt % of the formulation and a flow agent in an amount from about 0.1 to about 5.0 wt % of the formulation, produced by a process which comprises the steps of: a. blending the lanthanum carbonate and the pharmaceutically acceptable excipients to form a mixture; or b. blending the lanthanum carbonate and the pharmaceutically acceptable excipients, compressing the resulting combination into a slug material or roller compacting the resulting combination into a strand material, and milling the prepared material into a free flowing mixture; and c. compressing the mixture formed in steps a or b into a tablet, wherein the process is performed without wet granulation or drying, the diluent is dextrates, corn syrup, oligosaccharide, isomaltooligosaccharide, glucose, lycasin, xylitol, lactitol, erythritol, mannitol, isomaltose, polydextrose, dextrin, starch, fructose, xylitol, maltodextrin, maltitol, isomalt, lactose, sorbitol, microcrystalline cellulose, sucrose based diluent-binders, confectioner's sugar, calcium sulfate dihydrate, calcium lactate trihydrate, hydrolysed starches, dextrose, inositol, hydrolyzed cereal solids, amylase, or glycine, and the flow agent is magnesium stearate, talc, polyethylene glycol, silica, colloidal anhydrous silica, hydrogenated vegetable oils, glyceryl behenate, or glyceryl monostearate.
The lawsuit was filed in response to an ANDA (Abbreviated New Drug Applications) filed by Barr seeking USFDA approval to market and sell generic versions of Shire’s 500 mg, 750 mg, and 1 g FOSRENOL® (Lanthanum Carbonate) products.Under the Hatch-Waxman Act, because Shire filed its patent infringement lawsuit within 45 days of receiving Barr’s Paragraph IV notification letter, the FDA must refrain from approving Barr's ANDA for 30 months, or until a district court decision finding that the patents are invalid or not infringed, whichever occurs earlier. The stay on generic approval will expire on April 26, 2012 unless terminated earlier.Shire is confident in its intellectual property portfolio protecting FOSRENOL®, and will enforce its patents against infringers to the fullest extent allowed by law.
Innovator got approval for Lanthanum carbonate (Fosrenol) Chewable tablets 500mg on Oct 26, 2004, while, 750mg and 1gm were approved by USFDA on Nov 23, 2005
Earlier, Ippharmadoc reported Here that innovator confirmed receipt of Paragraph IV notice letter from Barr and Mylan.