DCT

3:16-cv-05079

Aurobindo Pharma Ltd v. AstraZeneca Ab

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Key Events
Complaint

I. Executive Summary and Procedural Information

  • Parties & Counsel:
  • Case Identification: 3:16-cv-05079, D.N.J., 08/18/2016
  • Venue Allegations: Venue is alleged to be proper as Defendants have consented to jurisdiction in the district by previously filing patent infringement lawsuits there and conduct substantial business within the district, including marketing and sales of the brand-name drug at issue.
  • Core Dispute: Plaintiff, a generic drug manufacturer, seeks a declaratory judgment that its proposed generic version of Prilosec OTC does not infringe two patents owned by Defendant and that one of the patents is invalid.
  • Technical Context: The technology concerns pharmaceutical processes and formulations for omeprazole, a widely used proton pump inhibitor for treating gastric acid-related conditions, marketed by Defendant as Prilosec OTC.
  • Key Procedural History: This is a declaratory judgment action filed under the Hatch-Waxman Act. Plaintiff Aurobindo provided Defendant AstraZeneca with a Paragraph IV certification asserting non-infringement of the patents-in-suit. AstraZeneca did not file an infringement suit within the statutory 45-day period, which creates the basis for this action. The complaint alleges that another generic manufacturer, Perrigo, holds a 180-day first-to-file marketing exclusivity which it has "parked" by not launching its product, thereby blocking subsequent filers like Aurobindo from entering the market. This lawsuit seeks a court decision of non-infringement, which could act as a "triggering event" to start a 75-day clock for Perrigo to either launch its product or forfeit its exclusivity.

Case Timeline

Date Event
1998-11-05 U.S. Patent No. 6,428,810 Priority Date
1998-11-18 U.S. Patent No. 6,403,616 Priority Date
2002-06-11 U.S. Patent No. 6,403,616 Issued
2002-08-06 U.S. Patent No. 6,428,810 Issued
2014-12-22 Aurobindo sends Paragraph IV notice letter to AstraZeneca
2015-07-30 Perrigo receives final FDA approval for its generic omeprazole product
2016-06-16 Aurobindo receives tentative FDA approval for its ANDA product
2016-08-18 Complaint for Declaratory Judgment Filed

II. Technology and Patent(s)-in-Suit Analysis

U.S. Patent No. 6,403,616 - “Chemical Process and Pharmaceutical Formulation,” issued June 11, 2002

The Invention Explained

  • Problem Addressed: The patent addresses the need for industrial processes that produce active pharmaceutical ingredients, specifically proton pump inhibitors like omeprazole, with properties that ensure good stability and suitability for manufacturing into final dosage forms (’616 Patent, col. 1:33-44).
  • The Patented Solution: The patent claims an improved process for manufacturing alkaline salts of proton pump inhibitors. The process involves reacting the base compound (e.g., omeprazole) with a cation source (e.g., a magnesium source) and is distinguished by a specific final step: washing the prepared alkaline salt with a "basic aqueous solvent mixture" (’616 Patent, col. 4:35-42). This washing step is intended to adjust the pH of the final bulk substance, which the patent suggests improves the dissolution characteristics of the final drug product (’616 Patent, Abstract; col. 2:20-28).
  • Technical Importance: For oral drugs like omeprazole, controlling the physico-chemical properties of the bulk substance is critical for ensuring consistent release and absorption profiles in the final dosage form, which is a key requirement for regulatory approval (’616 Patent, col.2:20-28).

Key Claims at a Glance

  • The complaint focuses on independent claim 1 (Compl. ¶59).
  • The essential elements of independent claim 1 are:
    • A process for manufacturing slightly soluble or less soluble alkaline salts of a specified chemical compound (substituted sulphinyl heterocycles like omeprazole).
    • The process comprises reacting the compound with a cation source in the presence of a base.
    • The process includes a "washing step" where the prepared alkaline salt is "washed with a basic aqueous solvent mixture."
  • The complaint alleges non-infringement of all claims, which depend from claim 1 (Compl. ¶¶ 57, 59).

U.S. Patent No. 6,428,810 - “Pharmaceutical Formulation Comprising Omeprazole,” issued August 6, 2002

The Invention Explained

  • Problem Addressed: Omeprazole is highly susceptible to degradation in acidic environments and must be protected by an enteric coating. However, the stability of the final formulation's release profile can be inconsistent, potentially shortening the product's shelf-life. The patent identifies that different batches of a common excipient, hydroxypropyl cellulose (HPC), can cause this variability (’810 Patent, col. 2:39-47).
  • The Patented Solution: The patent describes a multi-layered oral formulation for omeprazole. The formulation has a core containing the active drug, an intermediate "separating layer," and an outer enteric coating layer. The invention's key feature is the use of a specific quality of HPC in the separating layer, defined as having a "cloud point of at least 38° C." under specified test conditions (’810 Patent, Abstract; col. 3:1-14). This specific HPC is claimed to ensure a stable drug release rate over time, thereby extending the product's viable shelf life (’810 Patent, col. 2:60-66).
  • Technical Importance: Ensuring long-term stability and consistent drug release is a significant challenge in pharmaceutical formulation and is critical for both patient safety and the commercial viability of a drug product (’810 Patent, col. 2:32-39).

Key Claims at a Glance

  • The complaint focuses on independent claim 1 and challenges the validity of claims 1-22 (Compl. ¶¶ 76, 98).
  • The essential elements of independent claim 1 are:
    • An enteric coated oral pharmaceutical formulation.
    • Comprising (a) a core material with the active ingredient (e.g., omeprazole), (b) a separating layer, and (c) an enteric coating layer.
    • The separating layer comprises a hydroxypropyl cellulose (HPC).
    • The HPC has "a cloud point of at least 38° C." as measured by a specific test.
  • The complaint reserves the right to raise defenses against all claims (Compl. ¶42).

III. The Accused Instrumentality

Product Identification

The accused instrumentality is Plaintiff's "Proposed ANDA Product," identified as "omeprazole magnesium delayed-release tablets (OTC), eq. 20 mg base" (Compl. ¶42). This product is the subject of Plaintiff's Abbreviated New Drug Application (ANDA) No. 206877 (Compl. ¶39).

Functionality and Market Context

The product is a generic equivalent of Defendant's Prilosec OTC drug product (Compl. ¶1). It is an oral tablet designed for delayed release, intended to treat gastric acid-related conditions. The complaint positions the product as a lower-cost alternative to the brand-name drug, whose market entry is currently blocked by the patents-in-suit and by a first-to-file generic competitor's 180-day exclusivity period (Compl. ¶¶ 34, 49-50).

IV. Analysis of Infringement Allegations

No probative visual evidence provided in complaint.

’616 Patent Infringement Allegations

The complaint seeks a declaratory judgment of non-infringement. Its theory is that its manufacturing process omits a required step of the asserted claims.

Claim Element (from Independent Claim 1) Alleged Non-Infringing Functionality Complaint Citation Patent Citation
A process for the manufacturing of slightly soluble or less soluble alkaline salts of substituted sulphinyl... Plaintiff manufactures omeprazole magnesium, an alkaline salt of a substituted sulphinyl compound (Compl. ¶58). ¶58 col. 1:6-13
a washing step in which the prepared alkaline salt of the substituted sulphinyl compound is washed with a basic aqueous solvent mixture. Plaintiff alleges that its manufacturing process "do[es] not employ a washing step in which the prepared alkaline salt... is washed with a basic aqueous solvent mixture" (Compl. ¶60). ¶60 col. 4:38-42
  • Identified Points of Contention:
    • Factual Question: The central dispute will be a factual comparison of Aurobindo's actual manufacturing process (as detailed in its confidential ANDA) with the claim language. The key question is whether any step in Aurobindo's process constitutes washing with a "basic aqueous solvent mixture", either literally or under the doctrine of equivalents.
    • Scope Question: A potential dispute may arise over the definition of "basic aqueous solvent mixture." The patentee may argue for a broad interpretation, while the plaintiff may argue for a narrower one limited by the patent's examples, such as those containing sodium hydroxide or ammonia (’616 Patent, col. 4:40-42).

’810 Patent Infringement Allegations

The complaint does not provide sufficient detail for a non-infringement analysis of the ’810 Patent. Instead, the complaint's second count focuses almost exclusively on invalidating the patent, asserting that its claims are invalid for lack of enablement, lack of written description, anticipation, and obviousness (Compl. ¶¶ 77-98, 112-114). The implicit non-infringement argument is that the product does not use the claimed HPC, but the primary legal attack is on the patent's validity.

V. Key Claim Terms for Construction

  • ’616 Patent: "basic aqueous solvent mixture"

    • Context and Importance: This term is the sole basis for the non-infringement argument articulated in the complaint. The entire non-infringement case for the '616 patent hinges on whether Aurobindo's process uses a "washing step" with a solvent mixture that falls within the scope of this term.
    • Intrinsic Evidence for Interpretation:
      • Evidence for a Broader Interpretation: The patent uses the general term "base" and "solvent mixture," which could be argued to encompass a wide range of basic solutions beyond the specific examples (’616 Patent, col. 4:38-39).
      • Evidence for a Narrower Interpretation: The specification provides specific examples of suitable bases, namely "sodium hydroxide or ammonia," and a preferred mixture comprising "an alcohol, sodium hydroxide and water" (’616 Patent, col. 4:40-42). A party could argue the term should be construed in light of these specific disclosures.

  • ’810 Patent: "a cloud point of at least 38° C."

    • Context and Importance: This term is the central technical limitation of the invention. Its definition and validity are critical to both infringement and enablement/written description. Practitioners may focus on this term because the complaint alleges the patent fails to enable the full scope of the claim, particularly for HPC with higher cloud points (Compl. ¶¶ 83-86).
    • Intrinsic Evidence for Interpretation:
      • Evidence for a Broader Interpretation: The claim uses the plain language "at least 38° C.," which on its face covers any temperature at or above that threshold. The patentee would likely argue for this plain and ordinary meaning.
      • Evidence for a Narrower Interpretation: The patent defines "cloud point" very specifically as the temperature where light transmission is 96% under a specific test protocol using a Mettler instrument (’810 Patent, col. 8:1-14). An opponent might argue that the term's meaning is strictly tied to this explicit definition and the examples provided, and that the patent fails to enable the full, open-ended range of "at least 38° C" (Compl. ¶¶ 82-83).

VI. Other Allegations

Invalidity Allegations (primarily for the ’810 Patent)

The complaint forwards several arguments that the ’810 patent is invalid.

  • Lack of Enablement & Written Description: The complaint alleges the ’810 patent is invalid because its specification fails to teach a person of ordinary skill how to make and use the full scope of the claimed invention without undue experimentation. Specific allegations include that the patent provides no technical instruction on how to make the required HPC, gives no examples of HPC with a cloud point higher than 43°C, and provides only three working examples (Compl. ¶¶ 77-87).
  • Anticipation and Obviousness: The complaint asserts that claims of the ’810 patent are anticipated by prior art and that all claims are obvious over prior art references (Compl. ¶¶ 88, 93-94). The alleged theory is that prior art disclosed formulations with all the claimed elements except for the specific "cloud point" limitation, and that it would have been obvious to modify the prior art to include this feature to improve stability (Compl. ¶¶ 89, 96).

VII. Analyst’s Conclusion: Key Questions for the Case

  • A central issue for the ’616 patent will be one of factual comparison: Does Aurobindo’s confidential manufacturing process include a step that is functionally a "washing step" using a "basic aqueous solvent mixture" as defined by the claims, or does its process design successfully circumvent this limitation?
  • A key question for the ’810 patent will be one of patent validity: Does the patent’s specification provide adequate written description and an enabling disclosure for the full scope of a formulation containing HPC with "a cloud point of at least 38° C," or are the claims invalid for failing to teach the public how to practice the invention across that range?
  • The case also presents a significant procedural and commercial question under the Hatch-Waxman framework: Can this declaratory judgment action serve as the "triggering event" to force the forfeiture of a first-filer's 180-day marketing exclusivity, potentially accelerating generic competition for Prilosec OTC?