DCT
2:17-cv-05169
Cedars Sinai Medical Center v. Quest Diagnostic Inc
Key Events
Complaint
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Cedars-Sinai Medical Center (California)
- Defendant: Quest Diagnostics Incorporated (Delaware)
- Plaintiff’s Counsel: Wilson Sonsini Goodrich & Rosati
- Case Identification: 2:17-cv-05169, C.D. Cal., 07/13/2017
- Venue Allegations: Plaintiff alleges venue is proper because Defendant has committed acts of patent infringement in the Central District of California and maintains numerous regular and established places of business, including laboratories, within the district.
- Core Dispute: Plaintiff alleges that Defendant’s IBSDETEX diagnostic service infringes two patents related to diagnosing Irritable Bowel Syndrome (IBS) by detecting specific biomarkers, and further alleges that Defendant developed this service using trade secrets obtained during prior licensing negotiations under a confidentiality agreement.
- Technical Context: The technology provides a method for diagnosing post-infectious IBS, an organic subtype of the condition, by detecting antibodies to a bacterial toxin (CdtB) and a human protein (vinculin) involved in an autoimmune response.
- Key Procedural History: The complaint alleges that the parties engaged in licensing discussions under a confidentiality agreement starting in 2013, during which Plaintiff shared proprietary technical information and unpublished patent applications. After Defendant declined a license in late 2014, it allegedly used this information to launch its own competing diagnostic service in 2017.
Case Timeline
| Date | Event |
|---|---|
| 2009-02-11 | ’081 Patent Priority Date |
| 2012-09-17 | ’884 Patent Priority Date |
| 2013-11-24 | Parties allegedly entered into Confidentiality Obligations |
| 2014-12-23 | Quest informed Cedars-Sinai it was not interested in a license |
| 2015-08-18 | ’081 Patent Issue Date |
| 2017-04-01 | Quest allegedly began commercializing its IBSDETEX services (approx.) |
| 2017-07-11 | ’884 Patent Issue Date |
| 2017-07-13 | Complaint Filing Date |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 9,110,081 - Antibody to cytolethal distending toxin of campylobacter jejuni
- Patent Identification: U.S. Patent No. 9,110,081, "Antibody to cytolethal distending toxin of campylobacter jejuni," issued August 18, 2015.
- The Invention Explained:
- Problem Addressed: The patent’s background section notes that Irritable Bowel Syndrome (IBS) is a common disorder with an unclear pathophysiology, and that recent evidence suggests acute gastroenteritis (food poisoning) can precipitate the condition (’081 Patent, col. 1:49-59). This created a need for better diagnostic methods beyond those based on symptom exclusion (’081 Patent, col. 2:11-14).
- The Patented Solution: The invention provides a method for diagnosing IBS by detecting, in a biological sample, the presence of antibodies to cytolethal distending toxin (CDT), a toxin produced by bacteria that cause gastroenteritis (’081 Patent, Abstract). The presence of these antibodies, specifically to the CdtB subunit, indicates a prior infection and is correlated with a likely diagnosis of post-infectious IBS, thereby providing a direct biological marker for the condition (’081 Patent, col. 2:25-54).
- Technical Importance: The technology provided an objective, biomarker-based method for diagnosing at least a subset of IBS cases, challenging the prevailing view of IBS as a primarily functional or psychological disorder without a clear organic cause (Compl. ¶3, ¶18).
- Key Claims at a Glance:
- The complaint asserts independent claim 1 (Compl. ¶65).
- The essential elements of claim 1 are:
- Obtaining a biological sample from a subject with an IBS symptom.
- Using cytolethal distending toxin B (CdtB) or a fragment thereof to assay the sample and detect an antibody that binds specifically to CdtB.
- Determining the presence of IBS when the antibody is detected.
- Directing the subject to an IBS treatment when the antibody is detected.
U.S. Patent No. 9,702,884 - Methods for Detecting the Presence of Irritable Bowel Syndrome and System for Diagnosing Same
- Patent Identification: U.S. Patent No. 9,702,884, "Methods for Detecting the Presence of Irritable Bowel Syndrome and System for Diagnosing Same," issued July 11, 2017.
- The Invention Explained:
- Problem Addressed: While a link between bacterial infection and IBS was emerging, the specific biological mechanism connecting the two was not fully understood, creating a need for more precise diagnostics that could identify the cause of IBS and related motility disorders (’884 Patent, col. 1:30-54).
- The Patented Solution: The invention is based on the discovery of a specific autoimmune pathway. It explains that antibodies produced in response to bacterial CdtB toxin can, through molecular mimicry, cross-react with and create an autoimmune response against vinculin, a human protein (’884 Patent, col. 5:25-45). The patented method involves detecting these anti-vinculin antibodies in a patient's sample and comparing their level to a control to diagnose IBS (’884 Patent, Abstract).
- Technical Importance: This invention identified a specific autoimmune mechanism as a cause of post-infectious IBS, providing a more refined diagnostic target and further establishing an organic basis for the condition (Compl. ¶22).
- Key Claims at a Glance:
- The complaint asserts independent claim 1 (Compl. ¶69).
- The essential elements of claim 1 are:
- Providing a biological sample from a subject desiring an IBS diagnosis.
- Detecting a level of an anti-vinculin antibody using vinculin or a fragment thereof.
- Determining a presence or likely presence of IBS if the antibody level is higher than an established control level, which is determined from specific patient cohorts (e.g., healthy subjects or subjects with inflammatory bowel disease).
- Selecting a therapy for IBS if the presence of IBS is determined.
III. The Accused Instrumentality
Product Identification
- Quest Diagnostics' "IBSDETEX" diagnostic services (Compl. ¶25, ¶41).
Functionality and Market Context
- The IBSDETEX service is a blood test for diagnosing certain types of IBS (Compl. ¶25). The complaint includes a graphic from a Quest marketing brochure that outlines the "IBS-D/IBS-M pathophysiologic sequence" that the test is based on (Compl. ¶25). This sequence explicitly identifies "Bacterial toxin Cytolethal distending toxin B (CdtB)" and an "Autoimmunity response Vinculin" as key steps in the development of IBS (Compl. ¶25). The complaint alleges that Quest has been planning to provide these "lucrative services" for a significant time (Compl. ¶42). The complaint also presents a nearly identical diagram that it alleges was created by Plaintiff and shared with Quest under confidentiality obligations, suggesting the IBSDETEX service is based on Plaintiff's discoveries (Compl. ¶24).
IV. Analysis of Infringement Allegations
U.S. Patent No. 9,110,081 Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| obtaining a biological sample from a subject in need of a diagnosis regarding irritable bowel syndrome (IBS), wherein the subject has an IBS symptom; | Quest's IBSDETEX service requires obtaining a biological sample from a patient seeking an IBS diagnosis. | ¶65 | col. 25:5-8 |
| using cytolethal distending toxin B or a fragment thereof to assay the biological sample to detect the presence or absence of an antibody capable of binding specifically to CdtB or the fragment thereof; | Quest's service allegedly assays the sample to detect antibodies to CdtB, as evidenced by its marketing materials that identify CdtB as part of the disease pathway. | ¶25; ¶65 | col. 25:9-14 |
| determining the presence of IBS when the presence of the antibody capable of binding specifically to CdtB or the fragment thereof is detected; and | The IBSDETEX service provides a diagnostic result, thereby determining the presence of IBS. | ¶65 | col. 25:15-18 |
| directing the subject to an IBS treatment when the presence of the antibody capable of binding specifically to CdtB or the fragment thereof is detected. | The complaint alleges Quest performs this step by providing the diagnostic result, which informs and guides the subsequent treatment decision. | ¶65 | col. 25:19-22 |
- Identified Points of Contention:
- Scope Questions: A central question may be whether Quest, as a diagnostic testing provider, performs the step of "directing the subject to an IBS treatment." Quest may argue that it only provides a test result and that the patient's physician performs this step, raising a potential defense of non-infringement or an issue of divided infringement.
- Technical Questions: The complaint provides strong visual evidence from a Quest brochure that explicitly shows "Cytolethal distending toxin B (CdtB)" as a key component of the pathophysiological sequence underlying its IBSDETEX test (Compl. ¶25). This graphic directly supports the allegation that Quest's test assays for antibodies related to CdtB as required by the claim.
U.S. Patent No. 9,702,884 Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| providing a biological sample from a subject desiring diagnosis regarding irritable bowel syndrome (IBS); | Quest's IBSDETEX service is for subjects seeking an IBS diagnosis and requires a biological sample. | ¶69 | col. 43:1-3 |
| detecting in the biological sample, a level of an anti-vinculin antibody, wherein detecting comprises using vinculin, SEQ ID NO:1 or a fragment thereof to detect the anti-vinculin antibody; | Quest's marketing materials for the IBSDETEX service explicitly list an "Autoimmunity response Vinculin" as a step in the disease pathway, which the complaint alleges corresponds to detecting an anti-vinculin antibody. | ¶25; ¶69 | col. 43:4-8 |
| determining a presence or likely presence of IBS if the level of the anti-vinculin antibody is higher than an established control level... | The service allegedly determines the presence of IBS by comparing a detected antibody level to a control threshold. | ¶69 | col. 43:9-19 |
| selecting a therapy for IBS if the presence or likely presence of IBS is determined. | The complaint alleges Quest performs this step when its diagnostic result is used to guide therapy selection. | ¶69 | col. 43:20-22 |
- Identified Points of Contention:
- Scope Questions: Similar to the ’081 Patent, a key dispute will likely surround the "selecting a therapy" step. Quest may argue that this selection is performed by the physician, not the laboratory, presenting a divided infringement issue for the court.
- Technical Questions: The complaint's visual evidence is particularly pointed for this patent. The Quest brochure graphic features the term "Vinculin" under the heading "Autoimmunity response" (Compl. ¶25). This provides a direct link between the accused service and the central, novel element of the ’884 Patent's asserted claim.
V. Key Claim Terms for Construction
The Term: "directing the subject to an IBS treatment" (’081 Patent, claim 1) and "selecting a therapy" (’884 Patent, claim 1)
Context and Importance: These terms are critical because they define the final, active step of each asserted method claim. Practitioners may focus on these terms because their construction will be dispositive of the divided infringement issue. If construed to mean an action that only a physician can perform, Quest may not be liable for direct infringement. If construed more broadly to include providing the determinative information that dictates a course of treatment, Quest's actions may fall within the claim scope.
Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The patents frame the inventions as providing a definitive diagnosis that enables specific treatments (e.g., antibiotics for SIBO, which is a consequence of the detected biomarkers) (’081 Patent, col. 2:11-19; ’884 Patent, col. 2:11-15). A party could argue that providing the result that confirms this specific etiology is tantamount to "directing" or "selecting" the appropriate corresponding therapy.
- Evidence for a Narrower Interpretation: The claims use active verbs ("directing," "selecting"). A party could argue that the plain and ordinary meaning of these words requires an affirmative instruction or choice, an action not taken by a lab that merely reports a value. The specifications do not appear to provide an express definition that deviates from this plain meaning.
The Term: "established control level" (’884 Patent, claim 1)
Context and Importance: Infringement of claim 1 of the ’884 Patent requires comparing the detected anti-vinculin antibody level to a specific type of control level. Practitioners may focus on this term because Plaintiff must prove that the control methodology used by Quest's IBSDETEX service falls within the claim's specific definition.
Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The claim language "determined from a group of healthy subjects, a group of subjects with inflammatory bowel disease, or a group of subjects who are either healthy or have inflammatory bowel disease" provides several alternative bases for the control. A party could argue this disjunctive phrasing is broad enough to cover various standard methodologies for setting diagnostic thresholds.
- Evidence for a Narrower Interpretation: A party could argue that this language requires the control to be based directly on samples from these specific populations, as opposed to a more general statistical or commercially-derived threshold. The prosecution history, if examined, might reveal further limitations on how this level must be established.
VI. Other Allegations
- Indirect Infringement: The complaint alleges direct infringement under 35 U.S.C. § 271(a) and does not plead separate counts for indirect or contributory infringement (Compl. ¶65, ¶69).
- Willful Infringement: The complaint alleges that Quest's infringement has been willful for both patents (Compl. ¶66, ¶70). The basis for this allegation is Quest's alleged pre-suit knowledge of the patent applications, which it purportedly received during confidential licensing discussions on or before October 28, 2014, and its knowledge of the issued patents as of their respective issuance dates (Compl. ¶66, ¶70).
VII. Analyst’s Conclusion: Key Questions for the Case
- A central legal issue will be one of divided infringement: can Cedars-Sinai prove that Quest, as the diagnostic test provider, performs every step of the asserted method claims, including the final action steps of "directing...treatment" or "selecting a therapy," or will the court find that those steps are performed only by the ordering physician, thereby precluding a finding of direct infringement by Quest?
- A key evidentiary question will be one of technical and commercial linkage: how successfully can Cedars-Sinai connect the confidential information it allegedly shared with Quest during licensing negotiations to the specific technical implementation and marketing of the accused IBSDETEX service? The striking similarity between the "IBS Pathophysiologic Sequence" diagram (Compl. ¶24) and Quest's promotional graphic (Compl. ¶25) will be a focal point for both the patent infringement and trade secret misappropriation claims.
- The resolution of the case may also turn on a question of claim scope: can the term "vinculin" in the context of the ’884 patent, which is described as a human protein, be read to cover the "Autoimmunity response Vinculin" step advertised in Quest's service, and does Quest's method for determining its diagnostic thresholds align with the specific definition of an "established control level" recited in the claim?