DCT
1:15-cv-04524
Reckitt Benckiser LLC v. DR Reddys Laboratories Inc
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Reckitt Benckiser LLC (Delaware)
- Defendant: Dr. Reddy’s Laboratories, Inc. (New Jersey) and Dr. Reddy’s Laboratories, Ltd. (India)
- Plaintiff’s Counsel: SAUL EWING LLP; FITZPATRICK, CELLA, HARPER & SCINTO
- Case Identification: 1:15-cv-04524, D.N.J., 06/26/2015
- Venue Allegations: Plaintiff alleges venue is proper in the District of New Jersey because Defendant Dr. Reddy's Laboratories, Inc. is a New Jersey corporation with its principal place of business in the state, and because both defendants have previously submitted to the jurisdiction of the court in prior litigation.
- Core Dispute: Plaintiff alleges that Defendants’ filing of an Abbreviated New Drug Application (ANDA) to market generic versions of Plaintiff's Mucinex® D product constitutes an act of infringement of three patents related to extended-release guaifenesin formulations.
- Technical Context: The technology concerns oral pharmaceutical tablets designed to provide both immediate and sustained release of the expectorant guaifenesin, often in combination with other active ingredients, over a twelve-hour period.
- Key Procedural History: The lawsuit was initiated under the Hatch-Waxman Act following Defendants' submission of ANDA No. 208369 to the FDA and subsequent notification to Plaintiff via a Paragraph IV Certification letter dated May 18, 2015, asserting that the patents-in-suit are invalid, unenforceable, or would not be infringed by the proposed generic products.
Case Timeline
| Date | Event |
|---|---|
| 2000-04-28 | Earliest Patent Priority Date ('252, '821, '032 Patents) |
| 2002-04-16 | U.S. Patent No. 6,372,252 Issues |
| 2004-06-22 | FDA approves NDA for Mucinex® D |
| 2005-10-18 | U.S. Patent No. 6,955,821 Issues |
| 2010-11-23 | U.S. Patent No. 7,838,032 Issues |
| 2015-05-18 | Defendant sends Paragraph IV Notice Letter to Plaintiff |
| 2015-06-26 | Complaint for Patent Infringement Filed |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 6,372,252 - “Guaifenesin Sustained Release Formulation and Tablets”
- Patent Identification: U.S. Patent No. 6,372,252, “Guaifenesin Sustained Release Formulation and Tablets,” issued April 16, 2002 (’252 Patent, cover; Compl. ¶24).
The Invention Explained
- Problem Addressed: Guaifenesin, an expectorant, has a very short plasma half-life of approximately one hour, requiring frequent dosing with immediate-release tablets. This leads to a "series of three serum concentration profiles" with rapid increases and decreases in drug levels, providing only a "short window of therapeutic effectiveness" (’252 Patent, col. 2:20-35, col. 3:5-9). Existing sustained-release technologies at the time failed to provide effective relief for a full twelve hours.
- The Patented Solution: The patent describes a bi-layer tablet that combines two different release mechanisms. A first layer provides an "immediate release formulation" to quickly achieve a therapeutic blood concentration. A second, "sustained release" layer employs a specific matrix of a hydrophilic polymer (e.g., hydroxypropyl methylcellulose) and a water-insoluble polymer (e.g., an acrylic resin) that gels in the stomach and dissolves slowly in the intestines, maintaining the therapeutic effect for at least twelve hours (’252 Patent, Abstract; col. 3:42-55; Fig. 3). This combination is designed to achieve a maximum serum concentration (Cmax) comparable to an immediate-release tablet while providing a long duration of action.
- Technical Importance: This approach enabled the development of a twice-daily guaifenesin dosage form, intended to improve patient compliance and provide more consistent therapeutic effects compared to immediate-release products requiring dosing every four hours (’252 Patent, col. 2:14-30).
Key Claims at a Glance
- The complaint asserts infringement of one or more unspecified claims; independent claim 1 is representative of the core invention (Compl. ¶38; Prayer for Relief ¶A).
- Independent Claim 1:
- A modified release tablet having two portions,
- wherein a first portion comprises a first quantity of guaifenesin in an immediate release form which becomes fully bioavailable in the subject's stomach,
- and a second portion comprises a second quantity of guaifenesin and a release-delaying matrix comprising a hydrophilic polymer and a water-insoluble polymer,
- wherein the weight ratio of said hydrophilic polymer to said water-insoluble polymer is in the range of from about 1:1 to about 6.8:1,
- wherein said tablet demonstrates a maximum serum concentration (Cmax) in a human subject equivalent to the Cmax obtained when the first of three doses of a standard immediate release formulation...is dosed,
- and wherein said tablet also provides therapeutically effective bioavailability for at least twelve hours.
- The complaint's prayer for relief on "one or more claims" implicitly reserves the right to assert dependent claims (Compl. Prayer for Relief ¶A).
U.S. Patent No. 6,955,821 - “Sustained release formulations of guaifenesin and additional drug ingredients”
- Patent Identification: U.S. Patent No. 6,955,821, “Sustained release formulations of guaifenesin and additional drug ingredients,” issued October 18, 2005 (’821 Patent, cover; Compl. ¶26).
The Invention Explained
- Problem Addressed: The patent addresses the challenge of creating a single, twice-daily oral tablet that combines guaifenesin with at least one other active pharmaceutical ingredient (e.g., a decongestant) while ensuring both drugs are released appropriately to provide effective, long-lasting relief (’821 Patent, col. 1:15-28).
- The Patented Solution: The invention extends the bi-layer tablet technology of the parent ’252 Patent. It describes a formulation where at least one additional drug ingredient is incorporated into either the immediate-release layer, the sustained-release layer, or both, alongside guaifenesin. The underlying polymer matrix for controlling the sustained release remains a key component of the solution (’821 Patent, Abstract; col. 4:1-17). The patent's Figure 9, for example, illustrates the plasma concentration profile of the modified-release bi-layer tablet compared to an immediate-release version, showing both a rapid onset and sustained effect (’821 Patent, Fig. 9).
- Technical Importance: This technology facilitated the development of multi-symptom cold and cough remedies, such as Mucinex® D, in a convenient twice-daily dosage form, which was a significant advance in the over-the-counter market (’821 Patent, col. 1:15-28; Compl. ¶22).
Key Claims at a Glance
- The complaint asserts infringement of one or more unspecified claims; independent claim 1 is representative (Compl. ¶43; Prayer for Relief ¶E).
- Independent Claim 1:
- A modified release drug product comprising a first quantity of guaifenesin in an immediate release formulation...;
- a second quantity of guaifenesin in a release-delaying matrix; and at least one additional drug,
- wherein the release-delaying matrix comprises a hydrophilic polymer and a water-insoluble polymer in a weight ratio...from about 1:1 to about 9:1,
- wherein the immediate release formulation guaifenesin has a Cmax in a human subject equivalent to the Cmax obtained when...a standard immediate release formulation...is dosed,
- and wherein the drug product releases a therapeutically effective bioavailable guaifenesin dose for at least twelve hours.
- The complaint implicitly reserves the right to assert dependent claims (Compl. Prayer for Relief ¶E).
U.S. Patent No. 7,838,032 - “Sustained Release of Guaifenesin”
- Patent Identification: U.S. Patent No. 7,838,032, “Sustained Release of Guaifenesin,” issued November 23, 2010 (’032 Patent, cover; Compl. ¶28).
- Technology Synopsis: This patent, part of the same family as the ’252 and ’821 Patents, further details and claims specific pharmacokinetic (PK) outcomes for the bi-layer guaifenesin/pseudoephedrine tablet. It moves beyond the general formulation to claim specific quantitative results, such as achieving a Cmax and AUC (area under the curve) that fall within the FDA's bioequivalence window (80% to 125%) compared to separate doses of reference immediate-release products, while still providing at least twelve-hour effectiveness (’032 Patent, Abstract; col. 21:20-67).
- Asserted Claims: The complaint asserts infringement of unspecified claims; independent claims 1 and 5 are representative of the core technology claimed (’032 Patent, col. 60:8-67; Compl. ¶48).
- Accused Features: The DRL ANDA Products, as generic versions of Mucinex® D, are alleged to be formulated to produce the same claimed PK profiles, thereby infringing the patent (Compl. ¶¶ 23, 48).
III. The Accused Instrumentality
- Product Identification: The accused instrumentalities are Defendants’ proposed generic "guaifenesin and pseudoephedrine hydrochloride extended-release tablets, 600 mg/60 mg and 1.2 g/120 mg," for which they filed ANDA No. 208369 (Compl. ¶¶ 7, 30).
- Functionality and Market Context: The complaint alleges that "DRL's ANDA Products are copies of Plaintiff's Mucinex® D products" (Compl. ¶23). As such, they are intended to be bioequivalent versions of the branded drug, providing both immediate and sustained release of the active ingredients for use as an "expectorant and nasal decongestant" (Compl. ¶¶ 22, 33). By filing the ANDA, Defendants seek FDA approval to "engage in the commercial manufacture, use, or sell" these generic products in the United States before the expiration of the patents-in-suit, positioning them as direct competitors to Plaintiff's Mucinex® D (Compl. ¶7).
IV. Analysis of Infringement Allegations
The complaint alleges that by submitting ANDA No. 208369, Defendants committed a statutory act of infringement under 35 U.S.C. § 271(e)(2) (Compl. ¶¶ 38, 43, 48). The core of this allegation is that the product described in the ANDA, if commercially manufactured and sold, would meet all the limitations of the asserted patent claims. The complaint does not provide a detailed element-by-element infringement analysis but bases its allegations on the assertion that the accused products are "copies" of the commercial embodiment of the patents, Mucinex® D (Compl. ¶23).
'252 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| a modified release tablet having two portions, | DRL’s ANDA Product is alleged to be a bi-layer tablet formulation. | ¶23 | col. 3:42-44 |
| wherein a first portion comprises a first quantity of guaifenesin in an immediate release form... | DRL's ANDA Product allegedly contains an immediate release layer with guaifenesin designed for rapid dissolution. | ¶23, ¶36 | col. 9:31-36 |
| and a second portion comprises a second quantity of guaifenesin and a release-delaying matrix comprising a hydrophilic polymer and a water-insoluble polymer... | DRL's ANDA Product allegedly contains a sustained release layer with a polymer matrix matching the patent's description. | ¶23, ¶36 | col. 7:22-34 |
| wherein said tablet demonstrates a maximum serum concentration (Cmax)... equivalent to the Cmax obtained when... a standard immediate release formulation...is dosed... | DRL's ANDA Product is designed to be bioequivalent to Mucinex® D, which the patent asserts achieves this pharmacokinetic profile. | ¶23, ¶36 | col. 10:54-59 |
| and wherein said tablet also provides therapeutically effective bioavailability for at least twelve hours... | DRL's ANDA Product is an extended-release formulation intended to provide 12-hour relief. | ¶7, ¶33 | col. 3:15-18 |
'821 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| A modified release drug product comprising a first quantity of guaifenesin in an immediate release formulation... | DRL’s ANDA Product is alleged to be a bi-layer tablet with an immediate release layer containing guaifenesin. | ¶23, ¶36 | col. 12:13-21 |
| a second quantity of guaifenesin in a release-delaying matrix... | DRL's ANDA Product allegedly has a sustained release layer with guaifenesin in a polymer matrix. | ¶23, ¶36 | col. 8:62-67 |
| and at least one additional drug, | DRL's ANDA Product contains pseudoephedrine hydrochloride as the additional active ingredient. | ¶7 | col. 3:1-4 |
| wherein the immediate release formulation guaifenesin has a Cmax in a human subject equivalent to the Cmax obtained when...a standard immediate release formulation...is dosed... | DRL's ANDA Product is designed to be bioequivalent to Mucinex® D, which the patent asserts achieves this PK profile. | ¶23, ¶36 | col. 4:11-15 |
- Identified Points of Contention:
- Scope Questions: The infringement analysis may turn on the construction of several claim terms. For example, a question for the court could be whether the term "equivalent to" requires statistical identity with the Cmax of an immediate-release tablet or if it allows for bioequivalence within the standard 80-125% range used by the FDA. Similarly, the scope of the polymer weight ratios (e.g., "from about 1:1 to about 9:1" in the ’821 Patent) will be critical, as Defendants may argue their formulation falls outside this range.
- Technical Questions: A central evidentiary question will be whether the specific formulation detailed in Defendants' ANDA actually performs as claimed. For instance, what clinical or laboratory data exists to show that the DRL ANDA Product achieves both a Cmax "equivalent to" an immediate-release product and "therapeutically effective bioavailability for at least twelve hours" as required by claim 1 of the ’252 Patent?
V. Key Claim Terms for Construction
The Term: "a Cmax... equivalent to the Cmax obtained when... a standard immediate release formulation...is dosed" (from claim 1 of the ’252 and ’821 Patents).
Context and Importance: This term defines a key performance characteristic of the bi-layer tablet—that it must deliver a peak drug concentration comparable to a fast-acting tablet, thereby ensuring rapid relief. The definition of "equivalent" is central to the infringement analysis, as it sets the standard against which the accused product's performance will be measured.
Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The specification explains that a goal is to "improve the Cmax" over prior sustained-release forms, not necessarily to create a perfect replica of the immediate-release Cmax (’252 Patent, col. 2:42-49). Figure 9 of the ’252 Patent graphically depicts the Cmax of the modified-release product as being comparable to, but not identical to, the immediate-release peak, which may support a construction allowing for some deviation.
- Evidence for a Narrower Interpretation: A defendant might argue that the patentees chose the specific word "equivalent" to require a high degree of similarity, potentially approaching statistical identity, to distinguish their invention from prior art that failed to achieve such a rapid onset. The patent does not, however, provide an explicit numerical or statistical definition for the term.
The Term: "fully bioavailable in the subject's stomach" (from claim 1 of the ’252 Patent).
Context and Importance: This limitation describes the function of the immediate-release layer. Practitioners may focus on this term because its construction will determine what evidence is required to prove infringement. A dispute may arise over whether "in the subject's stomach" requires the drug to be absorbed from the stomach itself, or simply to be released and ready for absorption upon entering the small intestine.
Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The specification describes the immediate release portion as being "formulated to dissolve in aqueous acidic medium, such as that found in the stomach, to quickly release the guaifenesin" (’252 Patent, col. 10:48-52). This language focuses on the dissolution in stomach-like conditions, which may support a broader functional interpretation rather than requiring proof of absorption from the stomach organ itself.
- Evidence for a Narrower Interpretation: The plain language of the claim requires the drug to become "fully bioavailable" in the stomach. A defendant could argue this imposes a strict anatomical and physiological requirement that is distinct from simple dissolution, and may argue that most drug absorption occurs in the intestine, not the stomach, making the claim difficult to meet literally.
VI. Other Allegations
- Indirect Infringement: The complaint includes allegations that if Defendants commercialize their products, they will induce and contribute to infringement under 35 U.S.C. §§ 271(b) and (c) (Compl. ¶¶ 40, 45, 50). The alleged basis for inducement would be the product labeling and instructions, which would direct medical professionals and patients to administer the tablets in a manner that directly infringes the method claims of the patents.
- Willful Infringement: The complaint does not contain an explicit allegation of willful infringement.
VII. Analyst’s Conclusion: Key Questions for the Case
- A core issue will be one of definitional scope: How will the court construe the pharmacokinetic limitation "Cmax... equivalent to" that of an immediate-release standard? The case may turn on whether this requires near-identical performance or falls within the broader FDA bioequivalence guidelines, a distinction that will directly impact the infringement analysis.
- A key evidentiary question will be one of factual performance: Assuming a claim construction, will the specific formulation disclosed in Dr. Reddy’s ANDA, upon actual testing, produce the combination of rapid Cmax and 12-hour sustained bioavailability required by the claims, or will there be a demonstrable mismatch in its technical operation compared to the patented profiles?