DCT

3:18-cv-11134

Gilead Sciences Inc v. Strides Pharma Inc

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Key Events
Complaint

I. Executive Summary and Procedural Information

  • Parties & Counsel:
  • Case Identification: 3:18-cv-11134, D.N.J., 06/27/2018
  • Venue Allegations: Venue is alleged to be proper in the District of New Jersey because Defendant Strides Pharma, Inc. is incorporated in New Jersey.
  • Core Dispute: Plaintiffs allege that Defendants’ filing of an Abbreviated New Drug Application (ANDA) for a generic version of the HIV treatment drug Truvada® constitutes an act of infringement of six U.S. patents related to the drug's active ingredients and combination formulations.
  • Technical Context: The patents relate to antiviral nucleoside analogues and fixed-dose combination tablets used for the treatment of Human Immunodeficiency Virus (HIV), a significant global public health issue.
  • Key Procedural History: This action was initiated under the Hatch-Waxman Act following Defendants' notification to Plaintiffs, via a letter dated May 15, 2018, of their submission of ANDA No. 091055 containing a Paragraph IV certification. This certification asserts that the patents-in-suit are invalid or will not be infringed by the proposed generic product, thereby triggering the statutory basis for this infringement suit.

Case Timeline

Date Event
1990-02-01 U.S. Patent 6,642,245 Priority Date
1991-03-06 U.S. Patent 6,703,396 Priority Date
2003-01-14 U.S. Patents 8,592,397; 8,716,264; 9,457,036; 9,744,181 Priority Date
2003-11-04 U.S. Patent 6,642,245 Issued
2004-03-09 U.S. Patent 6,703,396 Issued
2004-08-02 FDA approves NDA for Truvada® for HIV-1 treatment
2013-11-26 U.S. Patent 8,592,397 Issued
2014-05-06 U.S. Patent 8,716,264 Issued
2016-10-04 U.S. Patent 9,457,036 Issued
2017-08-29 U.S. Patent 9,744,181 Issued
2018-05-15 Defendants send Paragraph IV Notice Letter to Plaintiffs
2018-06-27 Complaint Filed

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

U.S. Patent No. 6,642,245 - "Antiviral Activity and Resolution of 2-Hydroxymethyl-5-(5-fluorocytosin-1-yl)-1,3-oxathiolane"

The Invention Explained

  • Problem Addressed: At the time of the invention, there was a significant need for new pharmaceutical agents to treat HIV and Hepatitis B Virus (HBV) infections, as existing treatments like AZT had limitations related to efficacy and toxicity. (ʼ245 Patent, col. 1:39-2:68).
  • The Patented Solution: The patent discloses the compound 2-hydroxymethyl-5-(5-fluorocytosin-1-yl)-1,3-oxathiolane (emtricitabine, or "FTC"), its enantiomers, and derivatives. The invention is based on the discovery that this compound, particularly its (-)-β-L enantiomer, possesses high antiviral activity against HIV with very low toxicity to host cells. (ʼ245 Patent, Abstract; col. 4:15-24).
  • Technical Importance: The invention provided a novel nucleoside analogue with a favorable therapeutic profile, offering a new tool in the pharmacological arsenal against retroviruses like HIV. (ʼ245 Patent, col. 4:15-24).

Key Claims at a Glance

  • The complaint asserts at least Claim 1. (Compl. ¶39).
  • Independent Claim 1 contains the following essential elements:
    • A method for treating HIV infection in humans
    • comprising administering an effective amount of (-)-β-L-2-hydroxymethyl-5-(5-fluorocytosin-1-yl)-1,3-oxathiolane [emtricitabine]
    • or its physiologically acceptable salt
    • optionally in a pharmaceutically acceptable carrier
  • The complaint alleges infringement of dependent Claims 2, 4, 6, 7, and 8. (Compl. ¶39).

U.S. Patent No. 6,703,396 - "Method of Resolution and Antiviral Activity of 1,3-Oxathiolane Nucleoside Enantiomers"

The Invention Explained

  • Problem Addressed: Synthetic nucleosides are often produced as racemic mixtures of enantiomers (mirror-image isomers), but frequently only one enantiomer possesses the desired therapeutic activity while the other may be inactive or cause unwanted side effects. Efficiently separating these enantiomers is a significant challenge in pharmaceutical manufacturing. (ʼ396 Patent, col. 2:42-3:15).
  • The Patented Solution: The patent discloses a method for resolving racemic mixtures of nucleoside enantiomers by using an enzyme that preferentially catalyzes a reaction in only one of the enantiomers, allowing for their separation. This process is applied to FTC, isolating the therapeutically potent (-)-enantiomer. (ʼ396 Patent, Abstract; col. 5:1-17).
  • Technical Importance: This enzymatic resolution process provided a commercially viable method to produce an enantiomerically pure form of the active drug, improving its therapeutic index. (ʼ396 Patent, col. 5:1-4).

Key Claims at a Glance

  • The complaint asserts at least Claim 2. (Compl. ¶50).
  • Independent Claim 2 contains the following essential elements:
    • The compound (-)-Cis-4-amino-5-fluoro-1-(2-hydroxymethyl-1,3-oxathiolane-5-yl)-(1H)-pyrimidin-2-one [emtricitabine]
    • or a pharmaceutically acceptable salt, ester or salt of an ester thereof
  • The complaint alleges infringement of Claims 1, 3-7, 11-16, 22, and 23. (Compl. ¶50).

U.S. Patent No. 8,592,397 - "Compositions and Methods for Combination Antiviral Therapy"

  • Technology Synopsis: The patent addresses the need for chemically stable combination therapies for HIV to improve patient compliance and efficacy. It discloses a fixed-dose pharmaceutical dosage form combining tenofovir disoproxil fumarate and emtricitabine with specific excipients (binders, disintegrants, lubricants) that exhibits a defined level of chemical stability under specific storage conditions. (ʼ397 Patent, col. 2:5-15; col. 12:1-12).
  • Asserted Claims: At least Claim 1. (Compl. ¶61).
  • Accused Features: The accused feature is Strides' proposed fixed-dose combination tablet containing 300 mg of tenofovir disoproxil fumarate and 200 mg of emtricitabine, which is alleged to be chemically stable and contain the claimed types of excipients. (Compl. ¶61).

U.S. Patent No. 8,716,264 - "Compositions and Methods for Combination Antiviral Therapy"

  • Technology Synopsis: This patent is directed to a chemically stable fixed-dose combination of tenofovir disoproxil fumarate and emtricitabine. The invention claims a specific stability profile, wherein the combination exhibits less than 10% degradation after six months under accelerated storage conditions (40° C./75% relative humidity) when packaged with a desiccant. (’264 Patent, col. 2:5-15; col. 12:1-6).
  • Asserted Claims: At least Claim 1. (Compl. ¶72).
  • Accused Features: The accused feature is Strides' proposed fixed-dose combination tablet containing 300 mg of tenofovir disoproxil fumarate and 200 mg of emtricitabine, which is alleged to meet the specific chemical stability requirements of the claim. (Compl. ¶72).

U.S. Patent No. 9,457,036 - "Compositions and Methods for Combination Antiviral Therapy"

  • Technology Synopsis: Similar to the '397 Patent, this invention discloses a fixed-dose tablet combining tenofovir disoproxil fumarate and emtricitabine with specific classes of excipients. It further claims a heightened stability requirement, exhibiting equal to or less than 5% degradation of the active ingredients after six months under accelerated storage conditions. (’036 Patent, Abstract; col. 31:1-11).
  • Asserted Claims: At least Claim 1. (Compl. ¶83).
  • Accused Features: The accused feature is Strides' proposed fixed-dose combination tablet, which is alleged to contain the claimed active ingredients and excipients and meet the heightened chemical stability profile. (Compl. ¶83).

U.S. Patent No. 9,744,181 - "Compositions and Methods for Combination Antiviral Therapy"

  • Technology Synopsis: This patent claims a fixed-dose combination tablet of tenofovir disoproxil fumarate and emtricitabine that meets a specific chemical stability profile. The claimed combination exhibits equal to or less than 5% degradation of the active ingredients after six months under accelerated storage conditions when packaged with a silica gel desiccant. (’181 Patent, Abstract; col. 29:50-61).
  • Asserted Claims: At least Claim 1. (Compl. ¶94).
  • Accused Features: The accused feature is Strides' proposed fixed-dose combination tablet containing 300 mg of tenofovir disoproxil fumarate and 200 mg of emtricitabine, which is alleged to be a tablet that meets the specific chemical stability requirements of the claim. (Compl. ¶94).

III. The Accused Instrumentality

  • Product Identification: The accused instrumentality is the proposed generic drug product for which Defendants seek FDA approval via ANDA No. 091055. (Compl. ¶31). The complaint provides a visual of the chemical structure of Emtricitabine, a key active ingredient in the accused product. (Compl. ¶23).
  • Functionality and Market Context: The product is a fixed-dose oral tablet containing 200 mg of emtricitabine and 300 mg of tenofovir disoproxil fumarate. (Compl. ¶31). Its intended function is the treatment of HIV infection in humans. (Compl. ¶31). The complaint alleges that this generic product is intended to compete directly with Plaintiffs' branded Truvada® product upon receiving FDA approval. (Compl. ¶13).

IV. Analysis of Infringement Allegations

'245 Patent Infringement Allegations

Claim Element (from Independent Claim 1) Alleged Infringing Functionality Complaint Citation Patent Citation
A method for treating HIV infection in humans Defendants' ANDA seeks approval for a product that will be labeled for and used to treat HIV infection in humans. ¶39 col. 32:1-2
comprising administering an effective amount of (-)-β-L-2-hydroxymethyl-5-(5-fluorocytosin-1-yl)-1,3-oxathiolane [emtricitabine], or its physiologically acceptable salt Defendants' proposed product contains 200 mg of emtricitabine, which is alleged to be an effective amount for treating HIV infection. ¶39 col. 32:3-7
optionally in a pharmaceutically acceptable carrier. Defendants' proposed product is a tablet formulation, which is a pharmaceutically acceptable carrier. ¶39 col. 32:7-8

'396 Patent Infringement Allegations

Claim Element (from Independent Claim 2) Alleged Infringing Functionality Complaint Citation Patent Citation
(-)-Cis-4-amino-5-fluoro-1-(2-hydroxymethyl-1,3-oxathiolane-5-yl)-(1H)-pyrimidin-2-one [emtricitabine] or a pharmaceutically acceptable salt, ester or salt of an ester thereof. Defendants' proposed product contains emtricitabine as an active ingredient. ¶50 col. 17:23-28

Identified Points of Contention

  • Scope Questions: For the method claims of the ’245 Patent, a central question is whether the instructions and intended use described in the proposed label for Defendants' product will induce physicians and patients to perform the steps of the claimed method. For the compound claim of the ’396 Patent, the primary question is whether the emtricitabine in the proposed generic product is the specific enantiomer claimed. The complaint alleges that it is. (Compl. ¶50).
  • Technical Questions: For the formulation patents ('397, '264, '036, '181), a key evidentiary question will be one of functional equivalence and composition: does the formulation submitted in ANDA No. 091055 meet the specific stability limitations (e.g., "less than 10% degradation" or "equal to or less than 5% degradation") under the precise conditions recited in the claims? (Compl. ¶¶61, 72, 83, 94). Another question relates to an alleged typographical error in Claim 1 of the ’264 Patent, which recites storage at "70% relative humidity" while the complaint asserts it should be "75% relative humidity." (Compl. ¶72, n.1). This raises the question of whether the court will correct the claim and how that correction would impact the infringement analysis.

V. Key Claim Terms for Construction

  • The Term: "effective amount" (from Claim 1 of the ’245 Patent)
  • Context and Importance: This term is critical because infringement of the method claim requires administering an amount of emtricitabine sufficient to achieve the therapeutic outcome of "treating HIV infection." The construction of this term will define the dosage levels covered by the patent, and practitioners may focus on whether the 200 mg dosage in the accused product falls within this scope.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The specification does not define a precise numerical range for an "effective amount," instead describing it functionally as an "inhibitory amount" sufficient to inhibit viral replication without causing serious toxic effects. (ʼ245 Patent, col. 30:26-34). This could support a broad interpretation covering any clinically effective dose.
    • Evidence for a Narrower Interpretation: The specification provides exemplary dosage ranges, such as "from about 1 to 50 mg/kg, preferably 1 to 20 mg/kg, of body weight per day." (ʼ245 Patent, col. 30:35-39). A party could argue that these examples limit the scope of "effective amount" to ranges consistent with those disclosed, potentially raising a factual dispute about whether the 200 mg fixed dose in the accused product falls within that scope for a typical patient.

VI. Other Allegations

  • Indirect Infringement: The complaint alleges that Defendants will induce infringement of the '245 method patent because the product's label will instruct physicians and patients to administer the drug to treat HIV, thereby performing the claimed steps. (Compl. ¶40). For the formulation patents, the complaint alleges Defendants will actively encourage, aid, and abet the manufacture and use of the infringing tablets. (Compl. ¶¶62, 73, 84, 95).
  • Willful Infringement: The complaint does not explicitly use the term "willful," but it alleges that by filing the ANDA with a Paragraph IV certification, Defendants admit knowledge of the patents-in-suit. (Compl. ¶¶40, 51, 62, 73, 84, 95). The prayer for relief seeks trebled damages pursuant to 35 U.S.C. § 284, the statutory remedy for willful infringement, for any commercial acts post-approval. (Compl. Prayer ¶(s)-(x)).

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

  • A central issue for the four formulation patents ('397, '264, '036, '181) will be one of evidentiary proof: can Plaintiffs demonstrate that Defendants' proposed generic product, as described in its ANDA, will necessarily meet the specific quantitative stability limitations (e.g., "equal to or less than 5% degradation") recited in the asserted claims under the specified test conditions?
  • A key question of claim scope will arise from the alleged typographical error in Claim 1 of the ’264 Patent. The case may turn on whether the court agrees to correct the claim from "70% relative humidity" to "75% relative humidity" and how that decision impacts the comparison of the claim to the accused product's stability data.
  • For the method of treatment claim in the ’245 Patent, a core issue of induced infringement will be whether the proposed product label for the ANDA product is sufficient evidence of Defendants' specific intent to encourage or instruct others to perform the patented method, thereby infringing the patent upon commercial launch.