DCT
1:25-cv-00743
Pfizer Inc v. Orient Pharma Co Ltd
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Pfizer Inc. (Delaware) and related entities
- Defendant: Orient Pharma Co., Ltd. (Taiwan)
- Plaintiff’s Counsel: Morris, Nichols, Arsht & Tunnell LLP
- Case Identification: 1:25-cv-00743, D. Del., 06/16/2025
- Venue Allegations: Plaintiff alleges venue is proper as Defendant is a foreign corporation, which may be sued in any judicial district.
- Core Dispute: Plaintiff alleges that Defendant’s filing of an Abbreviated New Drug Application (ANDA) to market generic versions of Pfizer's Xeljanz® XR product constitutes an act of infringement of three patents related to sustained-release pharmaceutical formulations of tofacitinib.
- Technical Context: The technology concerns oral dosage forms of tofacitinib, a Janus kinase (JAK) inhibitor, formulated for once-daily sustained release to treat autoimmune diseases such as rheumatoid arthritis.
- Key Procedural History: This is a Hatch-Waxman action initiated in response to Defendant's submission of ANDA No. 219830 to the U.S. FDA. Defendant’s ANDA included a "Paragraph IV" certification asserting that the patents-in-suit are invalid, unenforceable, or will not be infringed by its proposed generic products. The complaint notes the patents-in-suit are listed in the FDA's "Orange Book" for Xeljanz XR.
Case Timeline
| Date | Event |
|---|---|
| 2013-03-16 | Earliest Priority Date for '181, '309, and '523 Patents |
| 2018-04-10 | U.S. Patent No. 9,937,181 Issues |
| 2020-05-05 | U.S. Patent No. 10,639,309 Issues |
| 2022-02-22 | U.S. Patent No. 11,253,523 Issues |
| 2025-04-30 | Orient sends Notice Letter regarding its ANDA filing |
| 2025-05-01 | Pfizer receives Orient's Notice Letter (on or around this date) |
| 2025-06-16 | Complaint Filed |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 9,937,181 - “Tofacitinib Oral Sustained Release Dosage Forms”
- Issued: April 10, 2018.
The Invention Explained
- Problem Addressed: The patent addresses the challenge of converting a twice-daily (BID) immediate-release drug, tofacitinib, into a convenient once-daily (QD) sustained-release formulation without compromising its therapeutic effect ('181 Patent, col. 2:21-29). The background notes that simply prolonging the drug's release duration can reduce its bioavailability and eliminate the beneficial "drug holiday"—periods where the drug concentration falls below the therapeutic threshold—which is a feature of the BID dosing profile and may be important for the drug's safety ('181 Patent, col. 3:1-9).
- The Patented Solution: The invention is a specific oral sustained-release dosage form of tofacitinib designed to provide an optimal pharmacokinetic profile for once-daily administration ('181 Patent, col. 3:10-20). The solution is not merely sustained release, but a formulation with a particular in vitro dissolution rate, achieved through an osmotic-pressure delivery mechanism, that aims to replicate the therapeutic benefits of the twice-daily regimen in a once-daily pill ('181 Patent, Abstract; col. 4:51-64).
- Technical Importance: This approach provides the patient convenience of a once-daily dose while seeking to maintain the established efficacy and safety profile of the original twice-daily immediate-release product ('181 Patent, col. 2:25-29).
Key Claims at a Glance
- The complaint asserts at least independent claim 1 (Compl. ¶46).
- Essential elements of claim 1:
- A once daily pharmaceutical dosage form comprising a core with 11 mg of tofacitinib (or equivalent salt) and an osmagen.
- A semi-permeable membrane coating around the core, which comprises a water-insoluble polymer.
- The form provides sustained release and has a specific in vitro dissolution profile: not more than 30% dissolved in 1 hour; 35-75% in 2.5 hours; and not less than 75% in 5 hours.
- The dosage form delivers the drug "primarily by osmotic pressure."
- The water-insoluble polymer is a cellulose derivative that sustains the release.
- The complaint does not explicitly reserve the right to assert dependent claims.
U.S. Patent No. 10,639,309 - “Tofacitinib Oral Sustained Release Dosage Forms”
- Issued: May 5, 2020.
The Invention Explained
- Problem Addressed: This patent, part of the same family as the '181 patent, addresses the same technical problem: designing a once-daily tofacitinib formulation that avoids the reduction in bioavailability and loss of the "drug holiday" associated with merely prolonging the release duration ('309 Patent, col. 3:1-20).
- The Patented Solution: Rather than defining the invention by its in vitro dissolution profile, this patent claims a once-daily sustained-release dosage form by its in vivo pharmacokinetic (PK) performance in a subject ('309 Patent, col. 5:1-12). The claims require the QD formulation to achieve an Area Under the Curve (AUC) that is 80% to 125% of the AUC of a 10 mg twice-daily immediate-release formulation, along with a specific ratio of maximum to minimum plasma concentration (Cmax to Cmin) ('309 Patent, claim 1).
- Technical Importance: Claiming the invention by its PK profile directly links the formulation to the desired therapeutic effect in the body, providing a different, performance-based scope of protection compared to the formulation-based claims of the '181 patent ('309 Patent, col. 3:10-20).
Key Claims at a Glance
- The complaint asserts at least independent claim 1 (Compl. ¶53).
- Essential elements of claim 1:
- A once daily pharmaceutical dosage form comprising 22 mg of tofacitinib (or equivalent salt).
- The dosage form is sustained release.
- When administered orally, it provides an AUC in the range of 80% to 125% of the AUC of a 10 mg tofacitinib immediate-release formulation administered twice daily.
- It provides a ratio of geometric mean plasma Cmax to Cmin from about 10 to about 100.
- The complaint does not explicitly reserve the right to assert dependent claims.
U.S. Patent No. 11,253,523 - “Tofacitinib Oral Sustained Release Dosage Forms”
- Issued: February 22, 2022.
Technology Synopsis
This patent is also from the same family as the '181 and '309 patents and addresses the same underlying technical problem of creating a once-daily tofacitinib formulation with a desired pharmacokinetic profile ('523 Patent, col. 2:21-29). The claims of the '523 patent are directed to methods of treating specific immunological disorders, such as rheumatoid arthritis, by administering the claimed once-daily, sustained-release tofacitinib dosage forms ('523 Patent, claim 1, claim 50).
Asserted Claims
The complaint asserts at least claim 1 (related to an 11 mg dose) and at least claim 50 (related to a 22 mg dose) (Compl. ¶60, ¶74).
Accused Features
The accused features are the intended uses of Orient's proposed generic 11 mg and 22 mg XR tablets for the treatment of diseases like rheumatoid arthritis, psoriatic arthritis, and ulcerative colitis, as will allegedly be directed by the product's labeling (Compl. ¶63, ¶77).
III. The Accused Instrumentality
Product Identification
The accused products are "Orient Generic 11 mg XR Tablets" and "Orient Generic 22 mg XR Tablets" (Compl. ¶2).
Functionality and Market Context
The accused products are proposed generic versions of Pfizer’s Xeljanz® XR extended-release tablets, intended for once-daily oral administration (Compl. ¶2). They contain tofacitinib citrate in amounts equivalent to 11 mg and 22 mg of tofacitinib base (Compl. ¶15, ¶38). The complaint alleges that Orient seeks FDA approval to market these products for the same indications as Xeljanz® XR, including the treatment of rheumatoid arthritis, psoriatic arthritis, ankylosing spondylitis, and ulcerative colitis (Compl. ¶17, ¶63, ¶77). Orient's filing of ANDA No. 219830 for these products is the basis of the lawsuit (Compl. ¶2).
No probative visual evidence provided in complaint.
IV. Analysis of Infringement Allegations
'181 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| A once daily pharmaceutical dosage form comprising a core comprising 11 mg of tofacitinib, or an equivalent amount of tofacitinib in the form of a pharmaceutically acceptable salt thereof, and an osmagen, | The complaint alleges that Orient's proposed 11 mg extended-release tofacitinib citrate product is a once-daily dosage form that infringes this claim. | ¶2, ¶38, ¶46 | col. 41:2-4 |
| and a semi-permeable membrane coating surrounding the core wherein said coating comprises a water-insoluble polymer, | The complaint alleges that Orient’s proposed generic product, by being a copy of Xeljanz® XR, will meet this limitation. | ¶2, ¶46 | col. 41:5-8 |
| wherein said dosage form is a sustained release dosage form, and when added to a test medium...dissolves not more than 30%...in 1 hour, and not less than 35% and not more than 75%...in 2.5 hours and not less than 75%...in 5 hours, | The complaint alleges Orient's ANDA filing for its proposed generic 11 mg extended-release tablet constitutes an act of infringement of this claim, implying the product will have the claimed dissolution profile. | ¶46, ¶48, ¶49 | col. 41:9-20 |
| and wherein said dosage form delivers the tofacitinib...primarily by osmotic pressure and wherein the water-insoluble polymer is a cellulose derivative that sustains release of the tofacitinib... | The complaint alleges Orient's ANDA filing constitutes an act of infringement, implying the product will have the claimed release mechanism. | ¶46, ¶48 | col. 41:21-26 |
Identified Points of Contention
- Technical Questions: A primary factual question will be whether Orient’s proposed 11 mg product actually exhibits the specific in vitro dissolution profile recited in claim 1. A second key technical question is whether Orient's formulation delivers tofacitinib "primarily by osmotic pressure" or if it achieves sustained release through a different mechanism, such as matrix erosion. The complaint does not contain technical data from Orient's ANDA to resolve these questions.
'309 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| A once daily pharmaceutical dosage form comprising 22 mg of tofacitinib, or an equivalent amount of tofacitinib in the form of a pharmaceutically acceptable salt thereof, wherein the dosage form is a sustained release dosage form, | The complaint alleges that Orient's proposed 22 mg extended-release tofacitinib citrate product is a once-daily, sustained-release dosage form that infringes this claim. | ¶2, ¶38, ¶53 | col. 5:1-4 |
| and when administered orally to a subject provides an AUC in the range of 80% to 125% of the AUC of 10 mg of tofacitinib...administered as an immediate release formulation BID, | The complaint alleges that Orient’s filing of an ANDA for a generic version of Xeljanz® XR, which is intended to be bioequivalent, constitutes an act of infringement, implying the product will meet the claimed AUC range. | ¶53, ¶55 | col. 5:4-8 |
| and wherein the sustained release dosage form provides a ratio of geometric mean plasma Cmax to Cmin from about 10 to about 100... | The complaint's allegation of infringement implies that Orient's proposed product will, upon administration, exhibit a Cmax to Cmin ratio falling within this claimed range. | ¶53, ¶55 | col. 5:8-12 |
Identified Points of Contention
- Scope Questions: A central question for the '309 Patent will be one of pharmacokinetic equivalence: does Orient’s proposed 22 mg product, upon administration to a subject, actually produce an AUC and a Cmax/Cmin ratio that fall within the ranges required by claim 1? The complaint lacks the bioequivalence data from Orient's ANDA that would be necessary to evaluate this.
- Legal Questions: The construction of the term "about" preceding the numerical range for the Cmax/Cmin ratio may become a point of contention if Orient’s product exhibits a PK profile near the boundary of the claimed range.
V. Key Claim Terms for Construction
"delivers the tofacitinib... primarily by osmotic pressure" (’181 Patent, claim 1)
- Context and Importance: This term is critical because it defines the mechanism of action for the claimed dosage form. Practitioners may focus on this term because infringement will depend on whether Orient's generic product uses this specific controlled-release mechanism. If Orient's product achieves sustained release through a different technology (e.g., a hydrophilic matrix system), it may not infringe.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The patent specification discloses multiple types of sustained-release technologies, including osmotic forms, matrix forms, and multiparticulate forms, suggesting the inventors contemplated various mechanisms for achieving sustained release ('181 Patent, col. 3:26-30). A party could argue "primarily" does not require the mechanism to be exclusively osmotic.
- Evidence for a Narrower Interpretation: The patent provides numerous, detailed examples of "Extrudable Core System Osmotic Tablets" ('181 Patent, col. 45:47-col. 58:49). A party could argue that these specific embodiments define the scope of the term and limit it to the types of osmotic pump systems described.
"a ratio of geometric mean plasma Cmax to Cmin from about 10 to about 100" (’309 Patent, claim 1)
- Context and Importance: This pharmacokinetic parameter is a central limitation defining the required in vivo performance of the accused product. While the infringement analysis will be a factual question of whether Orient's product meets this ratio, the construction of the word "about" could be dispositive.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The specification discloses this broad range of 10-100, while also identifying preferred narrower ranges of 20-40 and 20-30 ('309 Patent, col. 5:7-12). The use of "about" and the recitation of progressively narrower preferred ranges may suggest that the patentees intended the term to have some flexibility to account for experimental variability.
- Evidence for a Narrower Interpretation: The patent's stated objective is to create a QD profile that provides "drug holiday periods comparable to the PK profile of the BID immediate release tablets" ('309 Patent, col. 3:6-8). A party might argue that the term "about" should be construed narrowly to encompass only those values that are consistent with achieving this specific technical goal, as illustrated in the patent's examples.
VI. Other Allegations
Indirect Infringement
The complaint alleges both induced and contributory infringement of the '523 patent, which contains method-of-treatment claims. The complaint alleges Orient intends to induce infringement by providing a product with a label that instructs physicians and patients to administer it for the patented methods (Compl. ¶65-66, ¶79-80). Contributory infringement is alleged on the basis that Orient’s product is especially made for an infringing use and is not suitable for a substantial non-infringing use (Compl. ¶67-68, ¶81-82).
Willful Infringement
The complaint does not contain an explicit allegation of willful infringement. However, it does allege that Orient had knowledge of each of the patents-in-suit when it submitted its ANDA to the FDA, which could form the basis for a later willfulness claim based on post-suit conduct (Compl. ¶47, ¶54, ¶61, ¶75).
VII. Analyst’s Conclusion: Key Questions for the Case
- A core issue will be one of infringement on the merits: will Orient’s proposed generic products, upon manufacture and administration, actually practice the specific limitations of the asserted claims? This will require factual evidence from Orient's ANDA concerning its formulation's in vitro dissolution profile (for the ’181 patent) and its in vivo pharmacokinetic performance (for the ’309 and ’523 patents).
- A key technical question will be one of mechanism of action: does Orient's formulation achieve sustained release "primarily by osmotic pressure" as required by the ’181 patent, or does it employ a non-infringing alternative, such as a hydrophilic matrix system?
- A central legal question may be one of claim scope: how will the court construe functional and numerical limitations in the claims, such as the term "about" qualifying the pharmacokinetic ratios, which could determine the outcome if Orient's product performs at the edge of the claimed ranges?