PTAB

IPR2015-01490

Pharmacosmos AS v. Luitpold Pharmaceuticals Inc

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1. Case Identification

2. Patent Overview

  • Title: Methods and Compositions for Administration of Iron
  • Brief Description: The ’702 patent discloses methods for treating iron deficiency by administering a single, high dose (at least 0.6 grams) of an iron carbohydrate complex. The invention is presented as an improvement over prior art iron dextran therapies, which were associated with anaphylactoid-type reactions, by using complexes that are substantially non-immunogenic and do not cross-react with anti-dextran antibodies.

3. Grounds for Unpatentability

Ground 1: Anticipation of Claims 1-3, 10-13, 23, 25-27, and 41-43 by Geisser

  • Prior Art Relied Upon: Geisser (International Publication No. WO2004037865).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Geisser discloses every limitation of the challenged claims. Geisser teaches water-soluble iron carbohydrate complexes for treating iron-deficiency anemia, specifically noting that they can be administered parenterally in a single dose of 500-1000 mg (1.0 g), which satisfies the dosage requirements of independent claim 1 and its dependent claims. The complexes in Geisser are iron carboxymaltose, made from oxidized maltodextrin, which is one of the species explicitly recited in claim 1. Petitioner asserted that because Geisser’s complex is not a dextran derivative, it inherently has the claimed properties of being substantially non-immunogenic and having substantially no cross-reactivity with anti-dextran antibodies.
    • Key Aspects: Petitioner highlighted that the Patent Owner and the owner of Geisser’s U.S. counterpart (’109 patent) have effectively conceded Geisser’s relevance. Both the ’702 patent and the ’109 patent are listed in the FDA Orange Book as covering the same commercial product (Injectafer®), and in prosecuting a related patent, the Patent Owner amended claims to add a rate of administration limitation to overcome a rejection based on Geisser.

Ground 2: Anticipation of Claim 28 by Groman

  • Prior Art Relied Upon: Groman (Application # 2003/0232084).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner contended that claim 28, which depends from claim 1 and specifies an "iron polyglucose sorbitol carboxymethyl ether complex," is anticipated by Groman. Groman discloses administering these exact complexes (referred to as "carboxymethyl reduced dextran" or "CMRD") in single doses up to 0.6 grams for treating anemia. Groman explicitly teaches that its complexes are "immunosilent" and have a "minimal incidence of anaphylaxis," directly corresponding to the "substantially non-immunogenic" limitation. Furthermore, Groman provides data showing its complex exhibits minimal cross-reactivity (11%) with anti-dextran antibodies compared to a traditional iron dextran product (467%), satisfying the final limitation of the claim.

Ground 3: Obviousness of Claims 17, 34, and 47 over Geisser in view of Groman

  • Prior Art Relied Upon: Geisser (WO2004037865) and Groman (Application # 2003/0232084).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Geisser teaches the base method of claim 1, and Groman supplies the additional limitations of claims 17, 34, and 47. Claim 17 requires administration in "about 15 minutes or less," which Groman teaches for its structurally similar iron complex. Claim 34 requires a mean particle size no greater than 35 nm; Groman discloses complexes with mean volume diameters of 12-21 nm. Claim 47 requires intravenous injection as a bolus, a method of administration explicitly taught in Groman.
    • Motivation to Combine: A Person of Ordinary Skill in the Art (POSITA) would combine these references because both disclose advanced, safer parenteral iron therapies intended for high-dose administration. A POSITA would have looked to Groman’s teachings on administration rates (bolus, rapid infusion) and physical properties (particle size) to optimize the delivery of Geisser’s structurally analogous iron carboxymaltose complex.
    • Expectation of Success: A POSITA would have a high expectation of success because the carboxymaltose in Geisser and the carboxymethylated reduced dextran in Groman are structurally and functionally similar. Both are designed to form stable complexes with iron to allow for safe, high-dose administration, making Groman’s administration parameters directly applicable to Geisser’s compound.
  • Additional Grounds: Petitioner asserted additional challenges, including that claims 14 and 15 are anticipated by Van Zyl-Smit (a 2002 journal article) and that claim 30 is obvious over Van Zyl-Smit in view of Funk (a 2001 journal article). These grounds focused on the administration of iron polymaltose and specific iron core sizes.

4. Key Claim Construction Positions

  • "iron carboxymaltose complex": Petitioner proposed this term includes an iron carbohydrate complex obtained from oxidizing one or more maltodextrins with an aqueous hypochlorite solution. This construction was critical to map the claims onto the process disclosed in Geisser.
  • "iron polyglucose sorbitol carboxymethyl ether complex": Petitioner argued this term encompasses ferumoxytol and the "carboxymethyl reduced dextran" disclosed in Groman. This construction was necessary to establish that Groman teaches the specific complex required by claim 28.
  • "substantially no cross-reactivity with anti-dextran antibodies": Petitioner construed this to mean the level of cross-reactivity exhibited by a carbohydrate that is not a dextran, such as carboxymaltose. This interpretation supports the argument that Geisser’s non-dextran complex inherently meets this limitation.

5. Relief Requested

  • Petitioner requested institution of an inter partes review and cancellation of claims 1-3, 10-15, 17, 23, 25-28, 30, 34, 41-43, and 47 of Patent 7,754,702 as unpatentable.