DCT
2:10-cv-00534
Endo Pharma INC. v. Roxane LABORATORIES, INC.
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Endo Pharmaceuticals Inc. (Delaware) and Penwest Pharmaceuticals Co. (Washington)
- Defendant: Roxane Laboratories, Inc. (Nevada)
- Plaintiff’s Counsel: Dechert LLP
- Case Identification: 2:10-cv-00534, D.N.J., 01/29/2010
- Venue Allegations: Defendant Roxane is registered to do business in New Jersey and maintains a registered agent for service of process in the state.
- Core Dispute: Plaintiffs allege that Defendant’s filing of an Abbreviated New Drug Application (ANDA) for a generic version of the pain medication OPANA® ER constitutes an act of infringement of a patent related to controlled-release pharmaceutical formulations.
- Technical Context: The lawsuit concerns technology for oral solid-dose drug formulations that control the release of a medicament over an extended period, which is critical for maintaining consistent therapeutic blood levels and improving patient compliance.
- Key Procedural History: This action arises under the Hatch-Waxman Act, triggered by Roxane's filing of an ANDA with a "Paragraph IV certification," asserting its proposed generic product would not infringe the patent-in-suit. The '456 Patent is listed in the FDA's "Orange Book" for Plaintiffs' OPANA® ER product. The patent is subject to a terminal disclaimer. The complaint also certifies that Plaintiffs have filed separate infringement suits against Impax Laboratories, Sandoz, and Barr Laboratories over the same patent, suggesting a broad effort to enforce its patent rights against multiple generic challengers.
Case Timeline
| Date | Event |
|---|---|
| 1993-09-09 | '456 Patent Priority Date |
| 1999-09-28 | '456 Patent Issue Date |
| 2006-06-22 | FDA Approval for Plaintiff's OPANA® ER Tablets |
| 2007-10-19 | '456 Patent Listed in Orange Book for OPANA® ER |
| Prior to 2009-12-28 | Defendant Roxane Submits ANDA No. 200822 to FDA |
| c. 2009-12-28 | Defendant Roxane Sends Paragraph IV Notice to Plaintiffs |
| 2010-01-29 | Complaint Filing Date |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 5,958,456 - "Controlled Release Formulation (Albuterol)"
- Issued: September 28, 1999
The Invention Explained
- Problem Addressed: The patent describes a need for oral controlled-release drug delivery systems that can be adapted to match physiological requirements, maintain desired blood levels over extended periods (e.g., 12 or 24 hours), and are not susceptible to variable drug release. (’456 Patent, col. 1:21-34). Specifically, it notes that prior art excipients using only gelling agents like xanthan gum and locust bean gum "may not be sufficient to provide a suitable sustained release" for a 12 or 24-hour formulation. (’456 Patent, col. 5:20-29).
- The Patented Solution: The invention is a pharmaceutical formulation that combines a gelling agent with an inert pharmaceutical diluent and a "pharmaceutically acceptable hydrophobic material." (’456 Patent, Abstract; col. 2:1-6). The inclusion of the hydrophobic material, which can "slow the hydration of the gelling agent," provides an improved mechanism for controlling the rate of drug release from the tablet matrix when it is exposed to an environmental fluid like gastrointestinal fluid. (’456 Patent, col. 3:9-11; col. 5:30-41).
- Technical Importance: This formulation technology enabled the creation of oral tablets that provide a sustained therapeutic effect over a 12- or 24-hour period, potentially reducing the impact of food on drug absorption and allowing for manufacture using conventional methods. (’456 Patent, col. 2:25-34; col. 20:56-65).
Key Claims at a Glance
- The complaint does not identify specific asserted claims. Claim 1 is the broadest independent composition claim.
- Claim 1 (paraphrased elements):
- A controlled release solid dosage form for oral administration comprising:
- A therapeutically effective amount of a medicament;
- A sustained release excipient comprising a gelling agent;
- A pharmaceutically acceptable hydrophobic material; and
- An inert pharmaceutical diluent, where the ratio of the diluent to the gelling agent is from about 1:8 to about 8:1;
- Wherein the dosage form provides sustained release of the medicament when exposed to an environmental fluid.
- The complaint does not reserve the right to assert any other claims.
III. The Accused Instrumentality
Product Identification
The accused instrumentality is Defendant Roxane's proposed generic "oxymorphone hydrochloride extended-release oral tablets in a 40 mg strength" (Compl. ¶11). The act of infringement is the submission of Abbreviated New Drug Application (ANDA) No. 200822 to the FDA seeking approval to market this product. (Compl. ¶11, ¶16).
Functionality and Market Context
The complaint describes the accused product as a "generic version of OPANA® ER tablets" (Compl. ¶11). OPANA® ER is approved for the relief of "moderate-to-severe pain in patients requiring continuous, around-the-clock opioid treatment for an extended period of time" (Compl. ¶9). The complaint does not provide specific technical details of the accused product's formulation, grounding its infringement theory on the product's status as a generic equivalent to the Plaintiffs' patented product.
IV. Analysis of Infringement Allegations
The complaint alleges that the submission of the ANDA is a direct infringement under 35 U.S.C. § 271(e)(2)(A) but does not contain a claim chart or specific, element-by-element factual allegations. (Compl. ¶16). The infringement theory appears to be that because Roxane's product is a proposed generic version of OPANA® ER, its formulation must necessarily fall within the scope of the claims of the ’456 Patent.
No probative visual evidence provided in complaint.
'456 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| A controlled release solid dosage form for oral administration... comprising: a pharmaceutically effective amount of a medicament... | The proposed generic oxymorphone hydrochloride extended-release oral tablet, described as a 40 mg strength dosage form. | ¶11 | col. 21:7-12 |
| a sustained release excipient comprising a gelling agent; | The formulation for the proposed generic tablet, as detailed in ANDA No. 200822, which allegedly contains a gelling agent to achieve controlled release. | ¶11, ¶16 | col. 21:13 |
| a pharmaceutically acceptable hydrophobic material; | The formulation for the proposed generic tablet allegedly contains a hydrophobic material to control the drug release rate. | ¶11, ¶16 | col. 21:14 |
| and an inert pharmaceutical diluent wherein the ratio of said inert diluent to said gelling agent is from about 1:8 to about 8:1... | The formulation for the proposed generic tablet allegedly contains an inert diluent at the claimed ratio relative to the gelling agent. | ¶11, ¶16 | col. 21:15-18 |
| said dosage form providing a sustained release of said medicament when exposed to an environmental fluid. | The proposed generic tablet is an extended-release formulation designed to provide sustained release of oxymorphone hydrochloride. | ¶11 | col. 21:18-20 |
Identified Points of Contention
- Scope Questions: A primary dispute may concern whether the excipients in Roxane's formulation meet the definitions of "gelling agent" and "hydrophobic material" as those terms are used in the patent. The case will likely turn on whether Roxane has designed its formulation to achieve controlled release through a mechanism that avoids this specific combination of components.
- Technical Questions: A key question for discovery and trial will be the exact composition of Roxane's proposed product. The litigation will require a detailed comparison of the materials used in Roxane's formulation against the materials and functions described and claimed in the ’456 patent specification.
V. Key Claim Terms for Construction
Claim Term: "hydrophobic material"
- Context and Importance: This element appears to be a key point of novelty for the claimed formulation. Roxane’s non-infringement defense may argue that its formulation does not contain a "hydrophobic material" as defined by the patent, or that a component in its formulation does not function "to slow the hydration of the gelling agent" as described in the specification. (’456 Patent, col. 3:9-11).
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The specification provides a long, non-limiting list of candidate substances, including various celluloses, polymers, waxes, and oils, suggesting the term is meant to be capacious. (’456 Patent, col. 3:1-7).
- Evidence for a Narrower Interpretation: Parties may argue the term should be limited by its stated function of slowing the gelling agent's hydration or by the examples, which incorporate specific types of hydrophobic materials (e.g., carboxymethylcellulose, ethylcellulose) in specific ways (e.g., by granulating with the excipient). (’456 Patent, col. 5:30-41; col. 18:3-6).
Claim Term: "gelling agent"
- Context and Importance: The definition of "gelling agent" is central because the patent heavily emphasizes a "synergistic" combination of heteropolysaccharide and homopolysaccharide gums (e.g., xanthan gum and locust bean gum). (’456 Patent, col. 5:14-19). Practitioners may focus on this term because a non-infringement argument could be that the accused product uses a single polymer or a non-synergistic combination of polymers that falls outside the patent's definition of a "gelling agent."
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: Claim 1 recites the term in the singular ("a gelling agent"), which could support an interpretation that covers a single-component agent. The specification also provides a list of "other acceptable gelling agents" beyond the synergistic gums, such as alginates, carrageenan, and pectin. (’456 Patent, col. 6:37-44).
- Evidence for a Narrower Interpretation: The specification repeatedly highlights the "synergistic combination" as a core aspect of the technology, which could support a narrower construction limited to such combinations. (’456 Patent, col. 1:39-49).
VI. Other Allegations
Indirect Infringement
The complaint does not plead counts for indirect or contributory infringement. The sole infringement allegation is based on the statutory act of filing the ANDA under 35 U.S.C. § 271(e)(2)(A).
Willful Infringement
The complaint alleges that Roxane was aware of the ’456 Patent "as demonstrated by its reference to that patent in its ANDA" and that the filing of the Paragraph IV certification constitutes infringement. (Compl. ¶18). Plaintiffs also request a declaration that the case is "exceptional" and seek an award of attorneys' fees, which is the remedy for a finding of willful infringement. (Compl. Prayer ¶D).
VII. Analyst’s Conclusion: Key Questions for the Case
- A central issue will be one of compositional identity and claim construction: does the specific formulation disclosed in Roxane's ANDA contain components that meet the definitions of a "gelling agent" and a "hydrophobic material" as construed from the patent's specification? The case will likely depend on whether Roxane has successfully designed a controlled-release mechanism that avoids infringing the patent's claimed combination of excipients.
- A key procedural and strategic question will be one of validity: although the complaint states Roxane did not challenge the patent's validity in its notice letter, invalidity is a standard defense in ANDA litigation. If raised, the court will have to determine if the claimed formulation would have been obvious to a skilled pharmaceutical formulator in light of prior art controlled-release technologies existing before September 1993.