DCT
1:25-cv-12118
Braintree Laboratories Inc v. Alkem Laboratories Ltd
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Braintree Laboratories, Inc. (Massachusetts) and Sebela US Inc. (Delaware)
- Defendant: Alkem Laboratories Ltd. (India)
- Plaintiff’s Counsel: ROBINSON MILLER LLC
- Case Identification: 1:25-cv-12118, D.N.J., 06/25/2025
- Venue Allegations: Venue is alleged based on Defendant’s regular business in New Jersey, placement of products into the stream of commerce for distribution in the district, and Defendant’s prior submission to the Court's jurisdiction in other actions.
- Core Dispute: Plaintiffs allege that Defendant’s Abbreviated New Drug Application (ANDA) to market a generic version of Plaintiffs’ SUTAB® product constitutes an act of infringement of four patents related to solid oral sulfate salt formulations for colon cleansing.
- Technical Context: The technology concerns solid oral dosage formulations (tablets) for colon cleansing prior to procedures like colonoscopies, offered as an alternative to large-volume liquid preparations.
- Key Procedural History: This Hatch-Waxman litigation was triggered by Defendant Alkem’s submission of ANDA No. 220426 to the FDA and its subsequent notice letter, dated May 15, 2025, containing a Paragraph IV certification against the asserted patents, which are listed in the FDA's Orange Book for SUTAB®. The complaint also notes related litigations against other generic pharmaceutical manufacturers.
Case Timeline
| Date | Event |
|---|---|
| 2017-08-04 | Earliest Priority Date for all Asserted Patents |
| 2018-12-04 | U.S. Patent No. 10,143,656 Issues |
| 2020-11-10 | FDA Approves New Drug Application for SUTAB® |
| 2021-06-15 | U.S. Patent No. 11,033,498 Issues |
| 2022-07-12 | U.S. Patent No. 11,382,864 Issues |
| 2023-05-02 | U.S. Patent No. 11,638,697 Issues |
| 2025-05-15 | Defendant's Notice Letter Sent to Plaintiffs |
| 2025-06-25 | Complaint Filed |
II. Technology and Patent(s)-in-Suit Analysis
No probative visual evidence provided in complaint.
U.S. Patent No. 10,143,656 - “Solid Oral Sulfate Salt Formulations For Cleansing A Colon And Methods Of Using Same”
- Issued: December 4, 2018
The Invention Explained
- Problem Addressed: The patent describes the challenge of inadequate colon cleansing due to poor patient compliance with existing preparations. Large-volume liquid solutions are unpalatable, and prior solid-form alternatives, such as those based on phosphate salts, were associated with safety risks like renal failure (’656 Patent, col. 1:12-56).
- The Patented Solution: The invention is a solid oral dosage formulation—a tablet—that combines specific quantities of sodium sulfate, magnesium sulfate, and potassium chloride. This combination of poorly-absorbed sulfate salts creates an osmotic effect, inducing colon purgation effectively while being balanced to "reduce the likelihood of electrolyte shifts" (’656 Patent, col. 2:7-14; col. 5:36-55).
- Technical Importance: The formulation sought to provide the convenience and improved patient tolerance of a tablet-based colonoscopy prep without the significant safety concerns that had arisen with previous solid oral formulations.
Key Claims at a Glance
- The complaint asserts infringement of at least Claim 1 (Compl. ¶37).
- Independent Claim 1 requires:
- A solid oral formulation for cleansing a colon of a subject;
- The formulation comprises from about 34.0 grams to about 38.0 grams of sodium sulfate;
- The formulation comprises about 4.0 grams to about 8.5 grams of magnesium sulfate; and
- The formulation comprises about 3.0 grams to about 5.0 grams of potassium chloride.
- The complaint does not explicitly reserve the right to assert dependent claims, but alleges infringement of "one or more claims" (Compl. ¶37).
U.S. Patent No. 11,033,498 - “Solid Oral Sulfate Salt Formulations For Cleansing A Colon And Method Of Using Same”
- Issued: June 15, 2021
The Invention Explained
- Problem Addressed: The patent addresses the same patient compliance and safety issues as its parent, the ’656 Patent (’498 Patent, col. 1:21-59).
- The Patented Solution: Rather than claiming the formulation itself, this patent claims a method for cleansing the colon. The method requires administering the solid oral sulfate salt composition in a specific split-dose regimen, where a first dose is followed by a second dose, with each dose having a defined composition and being accompanied by administration of liquid (’498 Patent, Abstract; col. 11:1-21).
- Technical Importance: The invention defines a structured therapeutic regimen for the solid formulation, standardizing its administration to help ensure both efficacy and safety.
Key Claims at a Glance
- The complaint asserts infringement of at least Claim 1 (Compl. ¶45).
- Independent Claim 1 requires:
- A method of cleansing the colon, comprising:
- a) administering a first dose of a colon cleansing composition consisting essentially of an oral dosage form comprising about 17.75 g of sodium sulfate, about 2.7 g of magnesium sulfate, and about 2.25 g of potassium chloride;
- b) administering a first volume of liquid within two hours of the first dose;
- c) administering a second dose of the same composition; and
- d) administering a second volume of liquid within two hours of the second dose.
- The complaint alleges infringement of "one or more claims" (Compl. ¶47).
U.S. Patent No. 11,382,864 - “Solid Oral Sulfate Salt Formulations For Cleansing A Colon And Methods Of Using Same”
- Issued: July 12, 2022
- Technology Synopsis: This patent claims a method for colon cleansing by administering a specific solid oral sulfate formulation in a split-dose regimen. The claims focus on a highly structured schedule for co-administering six distinct volumes of water with the two doses of the formulation, aiming to ensure proper hydration and efficacy (’864 Patent, Claim 1).
- Asserted Claims: At least Claim 1 (Compl. ¶53).
- Accused Features: The proposed instructions for use in the labeling of Alkem’s generic product, which allegedly direct users to perform the patented method of administration (Compl. ¶¶52-53).
U.S. Patent No. 11,638,697 - “Solid Oral Sulfate Salt Formulations For Cleansing A Colon And Methods Of Using Same”
- Issued: May 2, 2023
- Technology Synopsis: This patent claims a solid oral formulation for colon cleansing defined by a specific composition. The claims recite precise quantities of sodium sulfate, magnesium sulfate, and potassium chloride and may also encompass specific excipients (’697 Patent, Claim 1).
- Asserted Claims: At least Claim 1 (Compl. ¶61).
- Accused Features: The specific chemical composition of Alkem’s proposed generic product as described in its ANDA filing (Compl. ¶¶60-61).
III. The Accused Instrumentality
Product Identification
- Defendant Alkem's proposed generic drug product that is the subject of ANDA No. 220426 (Compl. ¶30).
Functionality and Market Context
- The accused product is a generic version of Plaintiffs' SUTAB®, which is an osmotic laxative in tablet form used for cleansing the colon before a colonoscopy (Compl. ¶¶1, 12). The complaint alleges that Alkem has represented to the FDA that its product has the "same active ingredients, the same route of administration, the same dosage form, and the same strengths" as SUTAB®, and that it is bioequivalent (Compl. ¶¶31-32). The product is intended to compete directly with SUTAB® upon receiving FDA approval (Compl. ¶30).
IV. Analysis of Infringement Allegations
’656 Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| A solid oral formulation for cleansing a colon of a subject; the formulation comprising from about 34.0 grams to about 38.0 grams of sodium sulfate, | The total dosage of Alkem's proposed product allegedly contains a total amount of sodium sulfate that falls within the claimed range. | ¶¶31, 37 | col. 21:1-8 |
| about 4.0 grams to about 8.5 grams of magnesium sulfate, | The total dosage of Alkem's proposed product allegedly contains a total amount of magnesium sulfate that falls within the claimed range. | ¶¶31, 37 | col. 21:1-8 |
| and about 3.0 grams to about 5.0 grams of potassium chloride. | The total dosage of Alkem's proposed product allegedly contains a total amount of potassium chloride that falls within the claimed range. | ¶¶31, 37 | col. 21:1-8 |
’498 Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| A method of cleansing the colon, the method comprising: a) administering a first dose of a colon cleansing composition consisting essentially of an oral dosage form that comprises about 17.75 grams of sodium sulfate, about 2.7 grams of magnesium sulfate, and about 2.25 grams of potassium chloride; | The proposed labeling for Alkem's product allegedly instructs users to administer a first dose (e.g., 12 tablets) containing amounts of active ingredients that meet these limitations. | ¶¶45, 48 | col. 21:2-9 |
| b) administering a first volume of liquid within two hours of the first dose; | The proposed labeling allegedly instructs users to take the first dose with a volume of liquid within the specified timeframe. | ¶48 | col. 21:10-11 |
| c) administering a second dose of the colon cleansing composition...; and | The proposed labeling allegedly instructs users to administer a second dose with the same composition as the first. | ¶48 | col. 21:12-18 |
| d) administering a second volume of a liquid within two hours of the second dose... | The proposed labeling allegedly instructs users to take the second dose with a volume of liquid within the specified timeframe to cleanse the colon. | ¶48 | col. 21:19-21 |
Identified Points of Contention
- Scope Questions: A central question for the method claims (e.g., in the ’498 and ’864 Patents) is whether the specific instructions in Alkem's proposed product labeling will direct users to perform each and every step of the claimed methods. For the formulation claims (e.g., in the ’656 and ’697 Patents), the question is whether the precise quantitative composition of the manufactured generic product will fall within the claimed ranges.
- Technical Questions: For the formulation claims, a potential dispute may arise over whether Alkem's product meets the claimed weight ranges for the three active ingredients. For the method claims, a key question will be one of induced infringement: does the language of the proposed label actively encourage or instruct the specific dosing and liquid administration schedules required by the claims?
V. Key Claim Terms for Construction
The Term: "about"
- Patent Reference: e.g., ’656 Patent, Claim 1
- Context and Importance: The term "about" modifies all quantitative limitations in the asserted claims and is therefore critical for determining the boundary of literal infringement. The dispute will center on how much deviation from the recited gram amounts is permissible for Alkem's formulation to still be considered infringing.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The specification provides an explicit definition, stating, "As used herein, the term 'about' means within +/-10% of the recited value" (’656 Patent, col. 2:50-52). Plaintiffs may argue this definition is controlling and sets a clear, broad scope.
- Evidence for a Narrower Interpretation: A defendant could argue that, notwithstanding the specification's definition, the term should be interpreted more narrowly in the context of the specific examples, which disclose precise formulations (e.g., Table 1 showing 35.5 g of sodium sulfate) (’656 Patent, col. 13:Table 1).
The Term: "consisting essentially of"
- Patent Reference: ’498 Patent, Claim 1
- Context and Importance: This transitional phrase is crucial for the method claims, as it permits the presence of unlisted ingredients or steps so long as they do not materially affect the basic and novel properties of the invention. The infringement analysis will turn on whether any differences in Alkem's formulation (e.g., different excipients) or instructions materially alter the claimed colon cleansing method.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: A plaintiff would likely argue the "basic and novel" characteristic is simply osmotic colon cleansing, and therefore only the addition of other active laxative agents would be excluded. The patent does not explicitly define the term, favoring a broader interpretation based on the overall purpose.
- Evidence for a Narrower Interpretation: A defendant might argue that characteristics such as the safety profile, patient tolerability, or the specific electrolyte balance are also "basic and novel," and that different excipients or instructions could materially affect these properties, thereby placing the accused method outside the claim scope.
VI. Other Allegations
Indirect Infringement
- The complaint alleges both induced and contributory infringement for all four patents. The allegations are based on the premise that Alkem's proposed generic product and its labeling are "especially made or adapted for use in infringing" the patents, are unsuitable for any "substantial noninfringing use," and that Alkem's instructions will actively induce physicians and patients to perform the claimed methods (Compl. ¶¶40, 48, 56, 64).
Willful Infringement
- The complaint does not use the term "willful" but alleges for each patent that Alkem had "actual and constructive knowledge" of the patent prior to filing its ANDA and was aware that the filing itself "constituted an act of infringement" (Compl. ¶¶38, 46, 54, 62). These allegations establish a basis for a potential claim of post-filing willfulness.
VII. Analyst’s Conclusion: Key Questions for the Case
- A primary issue will be one of compositional identity: Does the formulation detailed in Alkem's ANDA contain quantities of sodium sulfate, magnesium sulfate, and potassium chloride that fall within the specific ranges recited in the asserted composition claims, particularly when the term "about" is construed?
- A key legal question will be one of induced infringement: Will the instructions on Alkem's FDA-approved label direct or inevitably lead medical providers and patients to administer the generic product according to the specific split-dosing and liquid-intake schedules required by the asserted method claims?
- A central underlying question, common to ANDA litigation, will be one of patent validity: Can Alkem prove by clear and convincing evidence that the asserted claims, which are directed to specific quantitative ranges and methods of using known salts, are invalid as obvious in light of prior art related to colon cleansing formulations?