Prior art — US Patent 11738124

Analysis of Prior Art for U.S. Patent 11,738,124

This analysis identifies and evaluates the most relevant prior art cited during the prosecution of U.S. Patent 11,738,124 ("the '124 patent"). The focus is on references that could potentially anticipate the patent's claims under 35 U.S.C. § 102, which pertains to novelty. The '124 patent, assigned to Haemonetics Corporation, claims a system and method for collecting a target volume of "pure plasma" by calculating and subtracting the volume of anticoagulant from the total collected volume, based on the donor's hematocrit.

The following prior art references are deemed most relevant to the core inventive concept of the '124 patent. This is not an exhaustive list of all citations but represents the patents that most closely describe the claimed invention.

1. U.S. Patent 5,681,273 A (Loken et al.)

Full Citation: US 5,681,273 A, "Systems and methods for predicting blood processing parameters"
Assignee: Baxter International Inc.
Filing Date: December 23, 1991
Publication Date: October 28, 1997
Brief Description: This patent describes systems and methods for predicting blood processing parameters for an individual subject before an apheresis procedure begins. It discloses inputting subject-specific data, including hematocrit and weight, into a controller. The system then uses this data to predict outcomes like the time required to collect a desired quantity of a blood component (e.g., plasma) and the total volume of anticoagulant that will be required. The goal is to optimize the procedure for the specific donor.
Potential Anticipation of Claims:
- Claim 1 (Method): The '273 patent discloses many elements of claim 1, including determining a donor's weight and hematocrit (claim 1a, 1b), withdrawing blood (1d), introducing anticoagulant (1e), and separating blood components (1f). However, Loken's system is primarily for predicting parameters before the procedure, rather than actively calculating the volume of "pure plasma" during the procedure and stopping based on that real-time calculation. While it uses hematocrit to calculate the total required anticoagulant, it does not explicitly teach the step of calculating the volume of anticoagulant in the collected plasma component and then calculating the volume of pure plasma to control the collection process in real-time as recited in claims 1(h) and 1(i).
- Claim 11 (System): Similarly, the '273 patent discloses a system with a controller that uses hematocrit and weight data. However, the controller is configured to predict outcomes, not necessarily to perform the specific real-time calculation of pure plasma volume and stop the blood draw pump based on reaching a "target volume of pure plasma" as recited in claim 11. The inventive step of the '124 patent appears to be the real-time calculation and control based on pure plasma volume, which is not explicitly detailed in the '273 patent.

2. U.S. Patent 4,086,924 A (Latham, Jr.)

Full Citation: US 4,086,924 A, "Plasmapheresis apparatus"
Assignee: Haemonetics Corporation
Filing Date: October 6, 1976
Publication Date: May 2, 1978
Brief Description: This is a foundational patent for Haemonetics' plasmapheresis technology. It describes an apparatus for separating blood into components, specifically for collecting plasma and returning red blood cells to the donor. The system includes a centrifuge bowl, pumps for whole blood and anticoagulant, and controls for managing the process. The process involves cycles of drawing and returning blood components.
Potential Anticipation of Claims:
- Claim 1 (Method) & Claim 11 (System): The '924 patent discloses the fundamental components and steps of a plasmapheresis system: a venous-access device, drawing blood, introducing anticoagulant, separating components in a centrifuge, collecting plasma, and returning other components (Claims 1c-g, 1j). It provides the basic hardware foundation described in claim 11. However, the '924 patent does not teach or suggest using the donor's hematocrit to calculate the volume of anticoagulant in the collected product or to determine a "pure plasma" volume as the endpoint for collection. The control system described is focused on managing the draw/return cycles and detecting interfaces between blood components (e.g., using optical sensors), not on standardizing the collected product volume by accounting for anticoagulant.

3. U.S. Patent 5,494,592 A (Latham, Jr. et al.)

Full Citation: US 5,494,592 A, "Apheresis apparatus and method"
Assignee: Haemonetics Corporation
Filing Date: April 27, 1993
Publication Date: February 27, 1996
Brief Description: This patent describes an apheresis system with an improved control method that allows for the collection of multiple blood products (e.g., plasma and platelets) concurrently or sequentially. It details a system that monitors the volume of collected components, for example, by weighing the collection bags. The controller adjusts the process based on these collected volumes and can switch between collection modes.
Potential Anticipation of Claims:
- Claim 1 (Method): The '592 patent discloses monitoring the volume/weight of the collected plasma component (relevant to dependent claims 5 and 6 of the '124 patent). It teaches a sophisticated control system that stops collection based on achieving a target volume. However, this target volume is for the total collected fluid (plasma plus anticoagulant). The patent does not disclose the crucial steps of using the donor's hematocrit to calculate the percentage of anticoagulant in the collected plasma and then calculating the "pure plasma" volume to use as the collection target (claims 1h, 1i).
- Claim 11 (System): This patent describes a system with a controller and weight sensors that is functionally very similar to the system in claim 11. The key difference remains in the programming of the controller. The '592 patent's controller stops collection based on the weight of the anticoagulated plasma, whereas the '124 patent's controller is specifically configured to perform the "pure plasma" calculation based on hematocrit and stop based on that calculated value.

Summary of Analysis

The key innovation claimed in U.S. Patent 11,738,124 is not the physical apparatus for plasmapheresis, which is well-established in the prior art cited. Instead, the inventive concept lies in the specific method of process control: the real-time calculation of "pure plasma" volume by accounting for the volume of anticoagulant (which varies based on donor hematocrit) and using this calculated "pure plasma" volume as the definitive endpoint for the collection procedure.

While the cited prior art, particularly US 5,681,273, discloses using donor-specific information like hematocrit to plan and optimize a procedure, it does not appear to describe the specific, dynamic calculation and control loop claimed in the '124 patent. Other references like US 4,086,924 and US 5,494,592 describe the necessary hardware and basic control of stopping collection based on a target volume, but this target is for the total mixture of plasma and anticoagulant, not for a standardized volume of pure plasma.

Therefore, under a 35 U.S.C. § 102 analysis, none of these single references appear to explicitly disclose all limitations of independent claims 1 and 11, particularly the calculation of pure plasma volume based on hematocrit and using that calculated value to terminate the collection. An argument for obviousness under 35 U.S.C. § 103, combining the teachings of these references, would be the more likely avenue for a validity challenge, as is being pursued in the instituted IPR (IPR2025-01374).