Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
DETAILED ACTION
Applicant’s request for continued examination filed July 22, 2026 is acknowledged. Claim 1 is amended and claims 2-3, 10-11, and 14-24 are canceled. Claims 1, 4-9, and 12-13 are pending and further considered on the merits.
Response to Amendment
In light of applicant’s amendment, the examiner modifies and the grounds of rejection set forth in the office action filed April 22, 2026.
Drawings
New corrected drawings in compliance with 37 CFR 1.121(d) are required in this application because element 2 referenced as a “feed tank” throughout the published specification (¶ 0027, 0029, 0031, etc.) is absent from any of the drawings. Applicant is advised to employ the services of a competent patent draftsperson outside the Office, as the U.S. Patent and Trademark Office no longer prepares new drawings. The corrected drawings are required in reply to the Office action to avoid abandonment of the application. The requirement for corrected drawings will not be held in abeyance.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claim 1 is rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Claim 1 recites a “feed vessel” and has been mapped to the “feed tank 2” within applicant’s published specification. However, element 2 is not present within any of the provided drawings. According to the specification, element 2 appears to coincide with the second buffer tank (REF 34 downstream from REF 32, fig. 1). It is unclear whether the recited “feed vessel” should be interpreted as the “feed tank” and/or “buffer tank” provided in the specification, whether the “feed vessel” should be interpreted as an additional (and omitted) component of the system, or some other alternative. For the purposes of examination, the examiner is interpreting the “feed vessel”, “feed tank”, and “buffer tank” to refer to the same component in applicant’s drawings (REF 34 downstream from REF 32). Appropriate correction in the claims and/or drawings is required.
Claim Rejections - 35 USC § 103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claim(s) 1, 4-9, and 12-13 is/are rejected under 35 U.S.C. 103 as being unpatentable over Goodrich et al., US 2021/0170336 (Goodrich, of record) in view of Rolinger et al., “Multi-attribute PAT for UF/DF of Proteins-Monitoring Concentration, particle sizes and Exchange” Analytical and bioanalytical chemistry, vol. 412, issue 9 (2020), pgs. 2123-2136 (Rolinger, IDS).
Regarding claim 1, Goodrich discloses a system for filtration of a feedstock (abstract, fig. 2, ¶ 0004) comprising:
A feed vessel (REF 102) containing a solution comprising a target biomolecule (see “bioproduction sample”, ¶ 0002, 0004);
A filter membrane (REF 124, ¶ 0032-0036, 0066) coupled to the feed vessel via a feed line (REF 126a), the filter membrane further coupled to the feed vessel via a retentate line (REF 128a);
A feed pump (REF 122, ¶ 0070) disposed in the feed line between the feed vessel and the filter membrane, the feed pump for moving solution from the feed vessel to the filter membrane;
A permeate line (see “PERMEATE” and fluidic coupling to REF 124) coupled to the filter membrane for delivering permeate to a permeate vessel;
A buffer vessel (REF 154, ¶ 0067) coupled to the feed vessel via a buffer supply line (REF 156a);
A diafiltration pump (REF 152, ¶ 0067) disposed in the buffer supply line for adding buffer from the buffer vessel to the feed vessel;
An ultraviolet sensor coupled to the feed line between the feed vessel and the feed pump (see “concentration readings of the sample”, and “sensors can be located at or near any component of the system”, ¶ 0070) configured to correlate in real time transmitted light with a concentration of a target biomolecule (figs. 7-8, ¶ 0096, 0105-0107, Table 2); and
A controller (REF 160, ¶ 0070) coupled to the ultraviolet sensor, the feed pump, and the diafiltration pump (¶ 0070) to receive information therefrom and to execute instructions for controlling the ultraviolet sensor, feed pump, and diafiltration pump to maintain a constant concentration of a target biomolecule throughout a diafiltration process (¶ 0070, 0095-0097, 0105-0107).
Goodrich does not disclose the ultraviolet sensor as a variable path-length instrument. However, Rolinger discloses a diafiltration system for filtration of biomolecule containing feedstocks (abstract, fig. 2) comprising a variable path-length instrument (see “variable pathlength (VP) ultraviolet and visible (UV/Vis) spectrometer, abstract, and “FlowVPE VP UV/Vis spectrometer”, Experimental setup, pg. 2124), the variable path-length instrument configured to transmit light through the solution and to correlate in realtime the transmitted light with a concentration of the target biomolecule in the solution (abstract, fig. 1).
At the time of invention, it would have been obvious to one having ordinary skill in the art to modify the system of Goodrich to utilize the variable path-length instrument described in Rolinger since it has been shown that alternate UV spectroscopy techniques are effective in diafiltration methods and that in-line variable path-length sensors are comparable to off-line HPLC analysis of product recovery streams with the added benefit of more reliable data acquisition (Rolinger, Results and discussion, pg. 2128)
Regarding claim 4, Goodrich (in view of Rolinger) discloses a system wherein the controller is programmed to execute instructions for receiving, from a user, input values for target concentration and/or diafiltration volume for the system to perform a combination of concentration and diafiltration steps (see “endpoint control”, ¶ 0096-0097).
Regarding claim 5, Goodrich (in view of Rolinger) discloses a system wherein the controller is programmed to execute instructions for periodically determining, based on information received from the variable path-length instrument, whether the concentration of the target biomolecule is within a predetermined range of the user input concentration (¶ 0094-0095).
Regarding claim 6, Goodrich (in view of Rolinger) discloses a system wherein the controller is programmed to execute instructions for periodically determining, based on information received from the variable path-length instrument, whether the concentration of the target biomolecule is equal to the user input final concentration (¶ 0094, 0096).
Regarding claims 7-8, Goodrich (in view of Rolinger) discloses a system wherein the filter membrane is a tangential flow filtration membrane comprising a TFF hollow-fiber cassette (¶ 0086-0087).
Regarding claim 9, Goodrich does not disclose a system wherein the controller provides a user-alert if the concentration departs from a user-specified range or user-specified predetermined amount. However, Rolinger discloses a system wherein a controller (see “custom made application”, Data acquisition and analysis, pg. 2126) is configured to provide a user-alert if the concentration of the target biomolecule, based on information provided by the variable path-length instrument, is determined to have departed from a user-specified range or user-specified value by a predetermined amount (see “small absolute deviations”, “most pronounced deviations”, In-line concentration measurements by VP UV/Vis spectroscopy, pg. 2128).
At the time of invention, it would have been obvious to one having ordinary skill in the art to modify the system of Goodrich to include the user-alert described in Rolinger in order to indicate sub-optimal or deviating process conditions to a user.
Regarding claim 12, Goodrich (in view of Rolinger) discloses a system further comprising a backpressure control valve (REF 139, ¶ 0070) disposed in the retentate line.
Regarding claim 13, Goodrich (in view of Rolinger) discloses a system further comprising pressure sensors in the feed line, the retentate line, and the permeate line (¶ 0070).
Response to Arguments
Applicant’s arguments with respect to the rejection(s) of claim(s) 1 under 35 U.S.C. 103 have been fully considered and are not found persuasive.
As an initial matter, applicant’s distinction between a feed stream and retentate stream as it relates to a circulating diafiltration process is not considered to provide an actual patentable distinction between those streams. Applicant’s retentate stream is returned to the feed vessel after filtration. The retentate stream combines with existing fluid and circulated through the system. Diafiltration systems (including the instant claims and prior art) generally consider the circulating stream to be simultaneously the feed stream and concentrate (or retentate) stream. Therefore, the distinction between the feed stream and retentate stream applied in the argument against the recited prior art is not found persuasive.
Applicant argues Goodrich does not disclose measuring a concentration of a target biomolecule in the feed stream. As seen above, the examiner considers the feed stream and retentate stream to be equivalent, where the retentate is returned to the feed vessel after filtration, as is typical in diafiltration. Goodrich discloses that the UV sensor is configured to provide a measurement to correlate transmitted light to a concentration of the target biomolecule in the feed/retentate stream (figs. 7-8, ¶ 0096, 0105-0107, Table 2). Additionally, since Goodrich discloses that “sensors can be located at or near any component of the system” (¶ 0070) and that said sensors can be provided upstream (fig. 7) or downstream (fig. 8) of the feed vessel to determine target biomolecule concentration (Example 2, ¶ 0105-0107, Table 2), the examiner maintains that such placement of the sensor within the feed line is disclosed by Goodrich.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to DIRK R BASS whose telephone number is (571)270-7370. The examiner can normally be reached 8-4:30 EST Monday-Friday.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Bobby Ramdhanie can be reached at (571) 270-3240. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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DIRK R. BASS
Primary Examiner
Art Unit 1779
/DIRK R BASS/Primary Examiner, Art Unit 1779
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