DCT
1:22-cv-01648
Mallinckrodt Pharma Ireland Ltd v. Airgas Therap LLC
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Mallinckrodt Pharmaceuticals Ireland Limited and Mallinckrodt Hospital Products IP Unlimited Company (Ireland)
- Defendant: Airgas Therapeutics LLC, Airgas USA LLC (Delaware), and Air Liquide SA (France)
- Plaintiff’s Counsel: Richards Layton & Finger PA
- Case Identification: 1:22-cv-01648, D. Del., 12/30/2022
- Venue Allegations: Venue is alleged to be proper in the District of Delaware because Defendants Airgas Therapeutics LLC and Airgas USA LLC are organized under the laws of Delaware and reside in the district. Venue over Air Liquide S.A., a French company, is alleged to be proper as it may be sued in any judicial district.
- Core Dispute: Plaintiff alleges that Defendants' filing of an Abbreviated New Drug Application (ANDA) to market a generic version of Plaintiff's INOmax® (nitric oxide) therapy constitutes an act of infringement of eleven patents related to methods of treatment and systems for delivering nitric oxide gas.
- Technical Context: The technology relates to the administration of inhaled nitric oxide gas, a therapy used to treat hypoxic respiratory failure in neonates, and the specialized systems and methods designed to ensure its safe and accurate delivery.
- Key Procedural History: The complaint notes that several related patents were previously asserted in Mallinckrodt v. Praxair, where certain claims of U.S. Patent Nos. 8,282,966; 8,293,284; 8,431,163; and 8795741 were found invalid under 35 U.S.C. § 101. Plaintiff explicitly states that the claims of the ’741 Patent asserted in the current action were not subject to the Praxair judgment.
Case Timeline
| Date | Event |
|---|---|
| 1999-12-22 | FDA approves INOmax® New Drug Application |
| 2006-12-01 | FDA begins approving INOmax® specialized delivery systems (DS, DSIR, DSIR Plus) |
| 2011-01-06 | Earliest Priority Date ('904, '209, '210, '794, '795, '911, '802, '993 Patents) |
| 2011-07-01 | Earliest Priority Date ('741 Patent) |
| 2011-11-07 | Earliest Priority Date ('570 Patent) |
| 2012-10-23 | U.S. Patent No. 8291904 Issues |
| 2013-11-05 | U.S. Patent No. 8573209 Issues |
| 2013-11-05 | U.S. Patent No. 8573210 Issues |
| 2014-02-19 | Earliest Priority Date ('9,794 Patent) |
| 2014-07-15 | U.S. Patent No. 8776794 Issues |
| 2014-07-15 | U.S. Patent No. 8776795 Issues |
| 2014-08-05 | U.S. Patent No. 8,795,741 Issues |
| 2016-02-23 | U.S. Patent No. 9265911 Issues |
| 2016-03-08 | U.S. Patent No. 9279794 Issues |
| 2016-03-29 | U.S. Patent No. 9295802 Issues |
| 2016-08-09 | U.S. Patent No. 9408993 Issues |
| 2017-09-26 | U.S. Patent No. 9770570 Issues |
| 2022-11-18 | Plaintiff receives Defendants' Paragraph IV Notice Letter |
| 2022-12-30 | Complaint Filed |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 9,770,570 - "Apparatus and method for monitoring nitric oxide delivery"
The Invention Explained
- Problem Addressed: The patent addresses the need to monitor and display the flow of therapeutic gas to ensure safe and accurate delivery, as variability in the flow from a support device like a ventilator can lead to shutdown of the delivery apparatus, potentially causing patient harm (US 9770570, col. 1:40-49).
- The Patented Solution: The invention is a method for monitoring gas delivery that involves measuring the flow rate of both the breathing gas and the therapeutic gas, using those values to calculate the actual delivered concentration of the therapeutic gas, and then presenting a visual indication on a display that compares this calculated concentration to the desired concentration (US 9,770,570, col. 2:48-67; Claim 1). This provides real-time feedback to the clinician.
- Technical Importance: This method provides clinicians with direct, calculated feedback on dosing accuracy, which may reduce the risk of over- or under-delivery of a potent medication like nitric oxide.
Key Claims at a Glance
- The complaint recites independent claim 1 (Compl. ¶40).
- Essential elements of Claim 1 include:
- receiving a desired concentration of therapeutic gas;
- providing a flow of breathing gas and a flow of therapeutic gas comprising nitric oxide;
- delivering a combined flow to a patient;
- measuring the flow rate of the breathing gas;
- obtaining the flow rate of the therapeutic gas;
- determining, using the flow rates, a calculated delivered concentration of the therapeutic gas; and
- presenting on a display a visual indication of the calculated concentration as a percentage comparison to the desired concentration, where the visual indication includes a first region for over delivery and a second for under delivery.
- The complaint asserts infringement of "one or more claims" of the ’570 patent, reserving the right to assert other claims (Compl. ¶114).
U.S. Patent No. 8,291,904 - "Gas delivery device and system"
The Invention Explained
- Problem Addressed: The patent background describes the importance of verifying the correct type and concentration of gas when administering therapy, noting that known computerized systems often do not communicate with the gas flow control valve, creating a risk of mismatch between the patient's required therapy and the gas being delivered (US 8291904, col. 1:21-46).
- The Patented Solution: The invention is a "smart" valve assembly that attaches to a gas container. The assembly includes a circuit with a memory to store "gas data" (e.g., gas concentration) and a transceiver that wirelessly communicates this data to a control module using "optical line-of-sight signals" (US 8,291,904, col. 2:4-21; Claim 1). This creates an integrated system where the control module can verify that the gas source matches the intended therapy.
- Technical Importance: This system automates a critical safety check by electronically linking the gas container's identity to the delivery system, reducing the potential for human error in administering a specific medical gas.
Key Claims at a Glance
- The complaint recites independent claim 1 (Compl. ¶61).
- Essential elements of Claim 1 include:
- A valve assembly to deliver gas from a container;
- The assembly comprises a valve attachable to the container and a circuit;
- The circuit includes a valve memory to store gas data (e.g., gas concentration); and
- The circuit also includes a valve processor and transceiver to send "wireless optical line-of-sight signals" to a control module to communicate the gas data.
- The complaint asserts infringement of "one or more claims" of the ’904 patent (Compl. ¶134).
U.S. Patent No. 8,573,209 - "Gas delivery device and system"
- Patent Identification: U.S. Patent No. 8573209, "Gas delivery device and system", issued November 5, 2013 (Compl. ¶62).
- Technology Synopsis: This patent is directed to a gas delivery device with a valve attachable to a gas source. The device includes a circuit with memory to store gas data (e.g., identification, expiration date, concentration) and a wireless transceiver to communicate that data to a control module to verify the correct gas is being used and is not expired (US 8,573,209, Abstract; Compl. ¶65).
- Asserted Claims: The complaint recites independent claim 1 (Compl. ¶65).
- Accused Features: The accused features are the Defendants' proposed generic nitric oxide product and the delivery system with which it is intended to be used (Compl. ¶17, 154).
U.S. Patent No. 8,573,210 - "Nitric oxide delivery device"
- Patent Identification: U.S. Patent No. 8573210, "Nitric oxide delivery device", issued November 5, 2013 (Compl. ¶66).
- Technology Synopsis: The patent claims a nitric oxide delivery device comprising a control module and a valve assembly. The valve assembly contains a circuit with memory to store gas data and a transceiver to send and receive wireless optical line-of-sight signals to communicate the data and verify the gas is correct and unexpired (US 8,573,210, Abstract; Compl. ¶69).
- Asserted Claims: The complaint recites independent claim 1 (Compl. ¶69).
- Accused Features: The accused features are the Defendants' proposed generic nitric oxide product and its associated delivery system (Compl. ¶17, 174).
U.S. Patent No. 8,776,794 - "Nitric oxide delivery device"
- Patent Identification: U.S. Patent No. 8776794, "Nitric oxide delivery device", issued July 15, 2014 (Compl. ¶70).
- Technology Synopsis: This patent describes a gas delivery device with a gas source and a valve that allows gas flow to a control module. The device includes a circuit with memory and a transceiver to communicate gas data (identification, expiration date, concentration) to the control module for verification (US 8,776,794, Abstract; Compl. ¶73).
- Asserted Claims: The complaint recites independent claim 1 (Compl. ¶73).
- Accused Features: The accused features are the Defendants' proposed generic nitric oxide product and its associated delivery system (Compl. ¶17, 194).
U.S. Patent No. 8,776,795 - "Gas delivery device and system"
- Patent Identification: U.S. Patent No. 8776795, "Gas delivery device and system", issued July 15, 2014 (Compl. ¶74).
- Technology Synopsis: This patent claims a gas delivery device for administering therapy gas from a source. It includes a valve and a circuit with a memory and a transceiver to send and receive signals, communicating gas data to a control module for verification of gas identity, concentration, and expiration date (US 8,776,795, Abstract; Compl. ¶77).
- Asserted Claims: The complaint recites independent claim 1 (Compl. ¶77).
- Accused Features: The accused features are the Defendants' proposed generic nitric oxide product and its associated delivery system (Compl. ¶17, 214).
U.S. Patent No. 9,265,911 - "Gas delivery device and system"
- Patent Identification: U.S. Patent No. 9265911, "Gas delivery device and system", issued February 23, 2016 (Compl. ¶78).
- Technology Synopsis: This patent covers a therapy gas delivery system with a device (comprising a drug source and a first circuit with memory/transceiver) and a control module (comprising a second memory/transceiver). The two transceivers communicate drug data to verify the drug's identity, concentration, and expiration status before delivery to a ventilator circuit (US 9,265,911, Abstract; Compl. ¶81).
- Asserted Claims: The complaint recites independent claim 1 (Compl. ¶81).
- Accused Features: The accused features are the Defendants' proposed generic nitric oxide product and its associated delivery system (Compl. ¶17, 234).
U.S. Patent No. 9,279,794 - "Systems and methods for compensating long term sensitivity drift of electrochemical gas sensors exposed to nitric oxide"
- Patent Identification: U.S. Patent No. 9279794, "Systems and methods for compensating long term sensitivity drift of electrochemical gas sensors exposed to nitric oxide", issued March 8, 2016 (Compl. ¶82).
- Technology Synopsis: The patent addresses the problem of sensor "drift" in devices that monitor nitric oxide delivery. It claims a method for compensating for this drift by identifying changes in the dosage setting, implementing a sensor recalibration schedule, and postponing calibration if an alarm is active to ensure accuracy (US 9,279,794, Abstract; Compl. ¶85).
- Asserted Claims: The complaint recites independent claim 1 (Compl. ¶85).
- Accused Features: The accused features are the methods of use of the Defendants' proposed generic nitric oxide product with an associated delivery and monitoring system (Compl. ¶17, 254).
U.S. Patent No. 9,295,802 - "Gas delivery device and system"
- Patent Identification: U.S. Patent No. 9295802, "Gas delivery device and system", issued March 29, 2016 (Compl. ¶86).
- Technology Synopsis: The patent claims a therapy gas delivery system with a device (drug source, memory, transceiver) and a control module. The components communicate to verify drug identification, expiration, and concentration before delivery to a subject via a ventilator circuit (US 9,295,802, Abstract; Compl. ¶89).
- Asserted Claims: The complaint recites independent claim 1 (Compl. ¶89).
- Accused Features: The accused features are the Defendants' proposed generic nitric oxide product and its associated delivery system (Compl. ¶17, 274).
U.S. Patent No. 9,408,993 - "Nitric oxide delivery device"
- Patent Identification: U.S. Patent No. 9408993, "Nitric oxide delivery device", issued August 9, 2016 (Compl. ¶90).
- Technology Synopsis: This patent covers a therapy gas delivery system with a device (drug source, circuit with memory/transceiver) and a control module. The system communicates drug data between the device and module to verify drug identity, concentration, and expiration before delivering nitric oxide to treat or prevent hypoxic respiratory failure (US 9,408,993, Abstract; Compl. ¶93).
- Asserted Claims: The complaint recites independent claim 1 (Compl. ¶93).
- Accused Features: The accused features are the Defendants' proposed generic nitric oxide product and its associated delivery system (Compl. ¶17, 294).
U.S. Patent No. 8,795,741 - "Methods for treating patients who are candidates for inhaled nitric oxide treatment"
- Patent Identification: U.S. Patent No. 8795741, "Methods for treating patients who are candidates for inhaled nitric oxide treatment", issued August 5, 2014 (Compl. ¶53).
- Technology Synopsis: This patent is directed to a method of treating neonatal patients that reduces the risk of pulmonary edema. The method involves identifying patients, determining whether they have pre-existing left ventricular dysfunction (LVD), and administering different treatment regimens based on that determination (US 8,795,741, Abstract; Compl. ¶56). Plaintiff alleges the asserted claims were not subject to the adverse judgment in the Praxair litigation (Compl. ¶36, 314).
- Asserted Claims: The complaint recites independent claim 24 (Compl. ¶56) and asserts claims 24-30 and 33 (Compl. ¶315).
- Accused Features: The accused features are the methods of use described in the proposed label for Defendants' generic nitric oxide product (Compl. ¶102, 315).
III. The Accused Instrumentality
Product Identification
- The accused instrumentality is Defendants' proposed generic "Nitric Oxide Gas for Inhalation, 800 ppm" product, for which Defendants filed ANDA No. 203144 seeking FDA approval (Compl. ¶1, 17).
Functionality and Market Context
- The complaint alleges that the Defendants' Proposed ANDA Product is a generic version of Mallinckrodt Inc's INOmax® product (Compl. ¶95). As such, it is alleged to have the same active pharmaceutical ingredient, dosage form, strength, and to be bioequivalent to INOmax® (Compl. ¶98-100). The product is intended for the same approved medical indication as INOmax®—treatment of hypoxic respiratory failure in neonates—and will be administered using a delivery system (Compl. ¶101, 31-32). No probative visual evidence provided in complaint.
IV. Analysis of Infringement Allegations
The complaint does not provide a detailed claim chart or narrative infringement theory beyond conclusory allegations. The following analysis is based on the implied infringement theory in an ANDA case: that the proposed generic product, when used as instructed by its proposed label, will infringe the asserted claims.
U.S. Patent No. 9,770,570 - Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| A method of monitoring the delivery of therapeutic gas to a patient comprising: receiving to a gas delivery device a desired concentration of therapeutic gas; | The use of Defendants' Proposed ANDA Product with a delivery system where a clinician sets a desired dose of nitric oxide. | ¶114 | col. 9:1-5 |
| providing a flow of breathing gas; providing a flow of therapeutic gas comprising nitric oxide; delivering a combined flow...to a patient; | The administration of the accused product via a ventilator or similar device that provides breathing gas and combines it with the therapeutic nitric oxide gas for delivery to the patient. | ¶114 | col. 9:6-14 |
| measuring via a first flow sensor a measured flow rate of the breathing gas; obtaining a flow rate of the therapeutic gas...; | Use of a delivery system that employs flow sensors to monitor both the breathing gas circuit and the therapeutic gas flow. | ¶114 | col. 10:1-3 |
| determining, using the flow rate of the therapeutic gas and the flow rate of the breathing gas, a calculated delivered concentration of therapeutic gas...; and | A delivery system controller that executes an algorithm to calculate the real-time concentration of nitric oxide being delivered to the patient based on the measured flow rates. | ¶114 | col. 10:4-11 |
| presenting on a display a visual indication of the calculated delivery concentration...wherein the visual indication includes a first region representing over delivery and a second region representing under delivery... | A user interface on the delivery system that displays the calculated concentration relative to the target concentration, visually indicating whether the dose is accurate, too high, or too low. | ¶114 | col. 10:12-23 |
Identified Points of Contention
- Scope Questions: A central question may be whether the term "visual indication" requires the specific graphical representation shown in the patent's figures (e.g., a bar graph with "over" and "under" regions) or if it can be read more broadly to cover any numerical or symbolic display that conveys the same information.
- Technical Questions: The analysis will depend on the specific functionality of the delivery system Defendants intend to use with their product. A key factual question will be what evidence shows that the system actually performs the claimed "determining" step using the specified inputs, as opposed to simply monitoring inputs without calculating a real-time delivered concentration.
U.S. Patent No. 8,291,904 - Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| A valve assembly to deliver a gas comprising NO from a gas container... the valve assembly comprising: a valve attachable to the gas container... | A valve assembly provided with or for use with Defendants' proposed nitric oxide gas cylinder. | ¶134 | col. 1:53-62 |
| a circuit supported within the valve assembly and disposed between the actuator and a cap, the circuit including: a valve memory to store gas data comprising gas concentration in the gas container and... | An electronic circuit integrated into the valve assembly that contains a non-volatile memory chip storing data about the gas in the cylinder. | ¶134 | col. 2:11-16 |
| a valve processor and a valve transceiver in communication with the valve memory to send wireless optical line-of-sight signals to communicate the gas data to the control module that controls gas delivery... | A microprocessor and an optical transmitter (e.g., infrared) within the valve assembly that wirelessly sends the stored gas data to the main delivery system controller. | ¶134 | col. 2:16-21 |
Identified Points of Contention
- Scope Questions: The term "wireless optical line-of-sight signals" is highly specific. A primary point of contention will be whether this term can be construed to read on other forms of short-range wireless communication, such as RFID or NFC, that do not strictly require line-of-sight. The prosecution history may be informative on this point.
- Technical Questions: Infringement will depend on the physical construction of the valve assembly used with Defendants' product. The presence of an on-board memory and a wireless transmitter, particularly an optical one, will be a critical factual issue.
V. Key Claim Terms for Construction
"visual indication... representing over delivery and... under delivery" (’570 Patent, Claim 1)
- Context and Importance: This term is central to the monitoring method. The infringement analysis will depend on whether the display on the accused system meets this limitation. Practitioners may focus on this term because its scope will determine whether a simple numerical readout of deviation from a target constitutes infringement, or if a more specific graphical interface is required.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The claim language itself does not specify the form of the visual indication, only its function—to represent over and under delivery. This may support a construction covering a range of user interfaces that achieve this function.
- Evidence for a Narrower Interpretation: Figure 5 of the patent depicts a specific graphical user interface with a vertical bar graph clearly demarcated with "Over Delivery" and "Under Delivery" regions (’570 Patent, Fig. 5). A defendant may argue this embodiment limits the claim scope to such graphical representations.
"wireless optical line-of-sight signals" (’904 Patent, Claim 1)
- Context and Importance: This term defines the specific communication protocol between the "smart valve" and the control module, a core feature of the claimed safety system. The case may turn on whether the accused system uses this exact technology. Practitioners may focus on this term because it appears to be a narrow technical limitation that could be a key point of non-infringement if the accused system uses a different wireless technology (e.g., radio frequency).
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The specification mentions that wired signals, such as an "optical cable," are an alternative, suggesting the invention is not strictly limited to one communication method (’904 Patent, col. 2:16-19). However, this may not broaden the scope of a claim that explicitly recites "wireless optical."
- Evidence for a Narrower Interpretation: The claim language is explicit and technical. The patent repeatedly emphasizes this specific communication method, describing it as a "wireless optical line-of-sight connection" (’904 Patent, col. 6:2-3). The term "optical" itself suggests communication via light (e.g., infrared), which inherently requires a line of sight, potentially excluding radio-frequency-based methods like RFID or Bluetooth.
VI. Other Allegations
- Indirect Infringement: The complaint alleges that Defendants will induce infringement by providing a product with instructions and a label that will inevitably cause physicians and healthcare providers to use it in a manner that practices the claimed methods (Compl. ¶126, 146, 327). It also alleges contributory infringement, stating that nitric oxide delivery systems are not staple articles of commerce suitable for substantial noninfringing use (Compl. ¶127, 147, 328).
- Willful Infringement: Willfulness is alleged based on Defendants' knowledge of the patents-in-suit prior to and upon filing their ANDA, as evidenced by the Paragraph IV certification letter sent to Plaintiff (Compl. ¶108, 117, 129, 137). The complaint alleges Defendants acted without a reasonable basis for believing they would not be liable for infringement (Compl. ¶119, 130, 139).
VII. Analyst’s Conclusion: Key Questions for the Case
- A core issue will be one of technical correspondence: Do the specific gas delivery and monitoring systems that Defendants will market for use with their generic drug actually incorporate the hardware and software features recited in the apparatus claims, particularly the "wireless optical line-of-sight" communication protocol of the '904 patent family and the specific "over/under delivery" display of the '570 patent?
- A second key issue will be one of induced infringement and claim scope: For the method of treatment claims (e.g., '741 patent), does the language of the Defendants' proposed label actively instruct clinicians to perform the specific patient-selection and differential-treatment steps required by the claims, and are those asserted claims patentably distinct from related claims previously invalidated in the Praxair litigation?
- A final evidentiary question will be one of commercial practice: Since the infringement allegation is based on the filing of an ANDA, the ultimate determination will depend on the precise characteristics of the product and the exact language of the product label that the FDA eventually approves for commercial sale.