Braintree Laboratories Inc v. Appco Pharma LLC

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Braintree Laboratories, Inc. (Massachusetts) and Sebela US Inc. (Delaware)
  • Defendant: Appco Pharma LLC (Delaware) and Somerset Therapeutics LLC (Delaware)
  • Plaintiff’s Counsel: Robinson Miller LLC
• Case Identification: 1:25-cv-10876, D.N.J., 06/13/2025
• Venue Allegations: Venue is alleged to be proper in the District of New Jersey because Defendants maintain regular and established places of business in the state, conduct business there, and the acts of infringement will have a substantial effect in New Jersey.
• Core Dispute: Plaintiffs allege that Defendants' filing of an Abbreviated New Drug Application (ANDA) to market a generic version of Plaintiffs' SUTAB® drug product constitutes an act of infringement of four patents covering solid oral formulations for colon cleansing.
• Technical Context: The technology concerns osmotic laxatives in tablet form, which are designed to offer a more tolerable alternative to traditional large-volume liquid preparations for cleansing the colon prior to a colonoscopy.
• Key Procedural History: The complaint notes that the asserted patents are listed in the FDA's "Orange Book" for SUTAB®. Plaintiffs also reference another pending litigation in the district involving Braintree and a different defendant, which may suggest a pattern of enforcement for this patent portfolio.

Case Timeline

Date	Event
2017-08-04	Earliest Priority Date for all Asserted Patents
2018-12-04	U.S. Patent No. 10,143,656 Issued
2020-11-10	SUTAB® (NDA No. 213135) Approved by FDA
2021-06-15	U.S. Patent No. 11,033,498 Issued
2022-07-12	U.S. Patent No. 11,382,864 Issued
2023-05-02	U.S. Patent No. 11,638,697 Issued
2025-05-02	Defendants' Notice Letter Sent to Plaintiffs
2025-06-13	Complaint Filed

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

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 historical difficulty patients have with colon cleansing preparations, citing poor compliance with large-volume, salty-tasting liquid solutions and the safety risks (e.g., renal failure) associated with earlier hypertonic tablet formulations based on phosphate salts (’656 Patent, col. 1:12-58).
• The Patented Solution: The invention is a solid oral dosage formulation (a tablet) that uses a specific combination of three sulfate salts—sodium sulfate, magnesium sulfate, and potassium chloride—to induce colon cleansing. This combination is designed to be osmotically active to purge the colon while balancing electrolyte levels to avoid clinically significant shifts in the patient's body (’656 Patent, col. 2:7-14; col. 4:43-54).
• Technical Importance: This approach provided a method for colon cleansing that avoided large liquid volumes, potentially improving patient tolerance and compliance, while using sulfate salts to mitigate the safety risks associated with phosphate-based tablets (’656 Patent, col. 1:46-58).

Key Claims at a Glance

• The complaint asserts at least independent claim 1 (Compl. ¶40).
• Claim 1 requires:
  • A solid oral formulation for cleansing a colon of a subject
  • comprising from about 34.0 grams to about 38.0 grams of sodium sulfate
  • about 4.0 grams to about 8.0 grams of magnesium sulfate, and
  • 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 infringement is alleged for "one or more claims" (Compl. ¶40).

U.S. Patent No. 11,033,498 - "Solid Oral Sulfate Salt Formulations For Cleansing A Colon And Methods Of Using Same"

Issued June 15, 2021

The Invention Explained

• Problem Addressed: As with the ’656 Patent, this patent addresses the need for a safe and effective solid oral formulation for colon cleansing that improves upon prior liquid and phosphate-based options (’498 Patent, col. 1:21-col. 2:14).
• The Patented Solution: This patent claims a specific method of cleansing the colon using a split-dosing regimen. The method involves administering a first dose of the sulfate salt composition, followed by liquid, and then later administering a second dose of the composition, also followed by liquid, to cleanse the colon (’498 Patent, col. 11:1-20). The specific amounts of each salt per dose are claimed.
• Technical Importance: The split-dosing methodology is a clinically important aspect of colon preparation, often believed to improve both the quality of the cleansing and patient tolerance compared to a single large dose (’498 Patent, col. 11:40-50).

Key Claims at a Glance

• The complaint asserts at least independent claim 1 (Compl. ¶48).
• 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 that comprises about 17.75 grams of sodium sulfate, about 2.7 grams of magnesium sulfate, and about 2.25 grams 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 a liquid within two hours of the second dose.
• The complaint alleges infringement of "one or more claims" (Compl. ¶48).

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, a continuation of the family, claims a method of cleansing the colon using a specific split-dosing regimen where defined amounts of the three-sulfate-salt composition are administered along with six distinct volumes of water administered at specific times relative to the solid doses (’864 Patent, claim 1). This claims a more granular and specific method of administration than the ’498 Patent.
• Asserted Claims: The complaint asserts at least independent claim 1 (Compl. ¶56).
• Accused Features: The accused features are the anticipated use of the Defendants' proposed generic drug product according to its instructions for use, which Plaintiffs allege will meet the specific dosing and liquid administration steps of the claims (Compl. ¶¶ 56, 59).

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 dosage formulation comprising specific amounts of sodium sulfate, magnesium sulfate, and potassium chloride, and further requires the inclusion of polyethylene glycol (PEG) (’697 Patent, claims 1, 2). This patent adds an additional required ingredient to the composition claimed in the ’656 patent.
• Asserted Claims: The complaint asserts at least independent claim 1 (Compl. ¶¶ 64, 66).
• Accused Features: The accused feature is the composition of the Defendants' proposed generic drug product itself, which the complaint alleges contains the claimed combination of three sulfate salts and will infringe if marketed (Compl. ¶¶ 64, 67). The complaint does not explicitly allege the presence of PEG in the accused product.

III. The Accused Instrumentality

Product Identification

• Defendants' proposed generic drug product that is the subject of Abbreviated New Drug Application (ANDA) No. 220327 (Compl. ¶1).

Functionality and Market Context

• The complaint alleges the accused product is a generic version of Braintree's SUTAB®, an osmotic laxative in tablet form indicated for cleansing the colon in preparation for a colonoscopy (Compl. ¶15).
• The product is alleged to contain 1.479 g sodium sulfate, 0.225 g magnesium sulfate, and 0.188 g potassium chloride per tablet (Compl. ¶33).
• The complaint asserts that the proposed generic has the same active ingredients, dosage form, and route of administration as SUTAB®, and is intended to be bioequivalent (Compl. ¶34).
• The filing of the ANDA itself represents a bid to enter the market with a lower-cost alternative to the branded SUTAB® product upon patent expiry or a finding of invalidity/non-infringement.

IV. Analysis of Infringement Allegations

No probative visual evidence provided in complaint.

'656 Patent 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...	Defendants' ANDA seeks approval for a solid oral tablet formulation for colon cleansing. The full cleansing regimen requires administration of 24 tablets.	¶¶34, 40	col. 4:1-10
...from about 34.0 grams to about 38.0 grams of sodium sulfate...	The total dosage of 24 tablets contains 35.5 g of sodium sulfate (1.479 g/tablet x 24), which falls within the claimed range.	¶¶33, 40	col. 4:55-61
...about 4.0 grams to about 8.0 grams of magnesium sulfate...	The total dosage of 24 tablets contains 5.4 g of magnesium sulfate (0.225 g/tablet x 24), which falls within the claimed range.	¶¶33, 40	col. 4:55-61
...and about 3.0 grams to about 5.0 grams of potassium chloride.	The total dosage of 24 tablets contains approximately 4.5 g of potassium chloride (0.188 g/tablet x 24), which falls within the claimed range.	¶¶33, 40	col. 4:55-61

'498 Patent 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... consisting essentially of an oral dosage form that comprises about 17.75 grams of sodium sulfate...	The proposed product's labeling is alleged to instruct a split-dosing regimen. The first dose of 12 tablets contains 17.75 g of sodium sulfate (1.479 g/tablet x 12).	¶¶48, 51	col. 11:40-50
...about 2.7 grams of magnesium sulfate...	The first dose of 12 tablets contains 2.7 g of magnesium sulfate (0.225 g/tablet x 12).	¶¶48, 51	col. 11:40-50
...and about 2.25 grams of potassium chloride;	The first dose of 12 tablets contains approximately 2.26 g of potassium chloride (0.188 g/tablet x 12).	¶¶48, 51	col. 11:40-50
c) administering a second dose of the colon cleansing composition...	The proposed labeling allegedly instructs administering a second dose of 12 tablets with the same composition as the first dose.	¶¶48, 51	col. 11:40-50

Identified Points of Contention

• Scope Questions: The method claims in the ’498 and ’864 Patents use the transitional phrase "consisting essentially of." A potential dispute is whether any different or additional excipients in the Defendants' generic product materially alter the basic and novel characteristics of the claimed method, which could be a route to argue non-infringement.
• Evidentiary Questions: For the method claims, infringement will depend entirely on the instructions for use included in the proposed labeling of the ANDA product. A central question for the court will be whether the Defendants' proposed label instructs users to perform each and every step of the claimed methods. For the ’697 Patent, the complaint does not allege that the accused product contains PEG, which is a required element of the asserted claim, raising a significant question about the basis for that infringement allegation.

V. Key Claim Terms for Construction

The Term: "about"

• Context and Importance: This term appears in the compositional claims of the ’656 Patent and the method claims of the ’498 Patent, defining the required weight ranges for the active ingredients. The scope of "about" is critical, as it determines the literal boundaries of the claims. A narrow interpretation could potentially allow a competitor to design around the patent by using amounts just outside the numerical ranges, while a broad interpretation could expand the patent's coverage.
• Intrinsic Evidence for Interpretation:
  • Evidence for a Broader Interpretation (or Defined Scope): The patent specification provides an explicit definition: "As used herein, the term 'about' means within +/-10% of the recited value" (’656 Patent, col. 2:50-52; ’498 Patent, col. 2:55-57). This provides a specific, quantifiable boundary that both parties will likely rely on, potentially simplifying the construction issue.
  • Evidence for a Narrower Interpretation: A party seeking a narrower scope might argue that the specific embodiments tested in the clinical trials, which use precise values (e.g., 35.5 g of sodium sulfate) (’656 Patent, Table 1), should limit the term's scope to a range closer to those exemplified values, despite the explicit definition.

The Term: "consisting essentially of"

• Context and Importance: This term, used in the method claims of the ’498 Patent, is a legal term of art that is open to interpretation. It is narrower than "comprising" but broader than "consisting of." The infringement analysis hinges on whether any unlisted ingredients in the Defendants' generic formulation (e.g., different binders, fillers, or lubricants) materially affect the "basic and novel properties" of the invention—namely, its ability to cleanse the colon safely and effectively via a split-dosing regimen.
• Intrinsic Evidence for Interpretation:
  • Evidence for a Broader Interpretation: Plaintiffs may argue that the "basic and novel" property is simply osmotic purgation from the specific combination of sulfate salts, and that standard pharmaceutical excipients do not materially affect this property.
  • Evidence for a Narrower Interpretation: Defendants may argue that properties like dissolution rate, palatability, or tablet stability are also "basic and novel" characteristics, and that their choice of different excipients materially affects these properties, thereby placing their product outside the scope of the claim.

VI. Other Allegations

Indirect Infringement

• The complaint alleges that Defendants will induce and contribute to infringement of the method patents (’498 and ’864 Patents) (Compl. ¶¶ 51, 59). This allegation is based on the assertion that Defendants' proposed product labeling will instruct physicians and patients to administer the generic drug in a manner that directly practices the steps of the claimed methods, and that the product is especially made for this infringing use and not suitable for a substantial non-infringing use (Compl. ¶¶ 43, 51).

Willful Infringement

• The complaint includes allegations that could support a willfulness claim. It asserts that Defendants had "actual and constructive knowledge" of the patents prior to filing the ANDA and were aware that the filing constituted an act of infringement (Compl. ¶¶ 41, 49, 57, 65). This is a standard allegation in an initial complaint that, if substantiated with evidence of pre-suit knowledge and egregious conduct, could form the basis for enhanced damages.

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

• A key evidentiary question will be one of compositional identity: Does the Defendants' proposed generic formulation, as described in its ANDA, contain elements (such as different excipients) that materially alter the basic and novel properties of the claimed invention, thereby taking it outside the scope of claims using the "consisting essentially of" transitional phrase?
• A second central issue will be one of instructional infringement: Will the final, FDA-approved label for the Defendants' generic product contain instructions that direct users to perform all the steps of the asserted method claims in the ’498 and ’864 patents, including the specific dosing amounts and liquid administration timing?
• A fundamental question of claim coverage exists for the ’697 patent: Given that the asserted claim requires polyethylene glycol (PEG) and the complaint does not allege its presence in the accused product, what is the factual basis for the allegation that the Defendants' ANDA submission infringes this specific patent?