Court of Appeal for Federal Circuit (CAFC) in a hearing en banc decision has upheld district court’s earlier decisions on motion for grant of summary Judgment of non-infringement (on appeal from Lupin) and refusal of preliminary injunction against various generic players w.r.t litigation on Cefdinir (Omnicef) 300 mg capsules, between innovator Abbott and Astellas against generic player Sandoz, Ranbaxy, Par and Lupin.
The following patent was at issue in Cefdinir litigation:
US4935507 (Assignee: Fujisawa Pharma, Date of Grant: June 19, 1990, Expiry: Dec 4, 2011):
The said patent has following independent claims:
1. Crystalline 7-[2-(2-aminothiazol-4-yl)-2-hydroxyiminoacetamido]-3-vinyl-3-cephem.-4-ca rboxylic acid (syn isomer) which shows the peaks at the diffraction angles about 14.7 about 17.8 about 21.5 about 22.0 about 23.4 about 24.5 about 28.1 in its powder X-ray diffraction pattern.
2. Crystalline 7-[2-(2-aminothiazol-4-yl)-2-hydroxyiminoacetamido]-3-vinyl-3-cephem-4-car boxylic acid (syn isomer) which is obtainable by acidifying a solution containing 7-[2-(2-aminothiazol-4-yl)-2-hydroxyiminoacetamido]-3-vinyl-3-cephem-4-car boxylic acid (syn isomer) at room temperature or under warming.
5. Crystalline 7-[2-(2-aminothiazol-4-yl)-2-hydroxyiminoacetamido]-3-vinyl-3-cephem-4-car boxylic acid (syn isomer) which is obtainable by dissolving 7-[2-(2-aminothiazol-4-yl)-2-hydroxyiminoacetamido]-3-vinyl-3-cephem-4-car boxylic acid (syn isomer) in an alcohol, continuing to stir the solution slowly under warming, then cooling the solution to room temperature and allowing the solution to stand.
Further, innovator’s patent ‘507 claims priority from Japanese patent application JP62-206199 (‘199 patent). The ‘199 patent disclosed crystalline form B (Cefdinir monohydrate) and crystalline form A (Cefdinir anhydrate), however, innovator claimed ‘507 patent broadly than ‘199 patent and used words like 'crystalline' to cover all crystalline forms in product-by-process claims 2-5 .
Generic players developed their non-infringing formulation using crystalline form B (Cefdinir monohydrate). Innovator Abbot’s marketed formulation contains crystalline form A (Cefdinir anhydrate). Also, generic players successfully designed around against the process limitation of product-by-process claims 2 to 5.
After filing ANDA on Cefdinir (Omnicef) 300 mg capsules, innovator sued various generic players. The district court construed the claims in the light of specification and prosecution history and other extrinsic evidences. Further, claim construction by district court suggested that ‘507 patent covers only form A.
The district court concluded that innovator’s ‘507 patent do not cover Form B (which innovator intentionally missed in ‘507 patent, although, priority patent application JP‘199 has disclosed both forms), accordingly, there is no infringement either literally or under the doctorine of equivalence.
The District Courts of Eastern Virginia granted summary Judgment of non-infringement motion by Lupin and District Courts of Illinois refused preliminary injunction against various generic players.
In the May 18, 2009 decision, the CAFC upheld the claim contruction and various elements decided by district courts in this decision. Also, court opined that infringement of a product-by-process claim (claim 2 and 5) requires practicing the claimed process step limitation in the accused product. Importantly, generic players are not using process element of claim 2 and 5 in the generic Cefdinir product, accordingly, there is no infringement.
Cefdinir is chemically 8-[2-(2-amino-1,3-thiazol-4-yl)-1-hydroxy-2-nitroso-ethenyl]amino-4-ethenyl-7-oxo-2-thia-6-azabicyclo[4.2.0]oct-4-ene-5-carboxylic acid and is a broad spectrum semisynthetic antibiotic. Innovator got approval from USFDA to market this drug on Dec 4, 1997
Opinion of the court Here
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