DETAILED ACTION
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 .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 01/12/2026 has been entered.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
Claim(s) 1, 4, 5, and 14 are rejected under 35 U.S.C. 103 as being unpatentable over Jensen et al ( WO2019156926A1, hereinafter, “Jensen”) in view of Steinbrueck et al (Poster, “REAlease™ Immunomagnetic Separation Technology with reversible labeling for positive selection of leukocytes”, 2017, hereinafter, “Steinbrueck”), and Miltenti (EP0819250B1) as evidenced by Miltenyi Biotec YouTube Video (“How to get label-free cells after cell sorting [WEBINAR]”, 2018).
Jensen teaches a closed-system manufacturing process for CAR-T cells (Abstract). Jensen teaches methods and compositions for producing genetically modified T cells. Jensen teaches the culturing CD4+ and CD8+ T cells and transduction of CD4+ and CD8+ T cells with lentivirus (Abstract). Jensen also teaches methods of producing genetically modified T cells in shorter periods of time compared to conventional methods (Abstract).
Regarding claim 1, Jensen teaches the generation of genetically modified T cells comprising the steps:
Providing a sample comprising T cells (Claim 1, Figure 2, ¶007, ¶008, ¶0015, Table 1, Table 2).
Preparing said sample by centrifugation (Table 2 Step 4).
Enriching the T cells of step b, wherein the T cells are enriched for CD4 and/or CD8 positive T cells (Figure 2, ¶0015). Jensen teaches samples are subjected to apheresis to obtain T cells. The CD4+ and CD8+ T cells are then selected and sorted (Figure 2, ¶0015).
Activating the T cells using CTS Dynabeads CD3/CD28 and removing the Dynabeads (Claim 6, Claim 33, Table 2 Step 8).
Genetically modifying the activated T cells by transduction with lentiviral vector particles, wherein after the genetic modification of the T cells by transduction with lentiviral vector particles residual vector particles are removed. While Jensen does not explicitly teach a result of a 10-fold reduction of lentiviral vector particles, the washing step described in Table 1, Harvest Step 4, absent evidence to the contrary, would remove residual vectors (Table 1 and 2 Transduction, Harvest).
Removing the modulatory agents using magnets and wherein the method is performed in 72 hours and does not undergo expansion in vitro (Claims 20 and 30, Table 1 and 2 Harvest, ¶0007, ¶0013, ¶0014).
Jensen does not explicitly teach the selection of CD4 and CD8 T cells using CD4 and/or CD8 as a positive selection marker.
However, Steinbrueck teaches immunomagnetic enrichment of leukocytes (Introduction). Steinbrueck teaches that many “enrichment strategies using magnetic labeling of the target cells allow for highly efficient isolation, but in some instances removal of residual cell surface labeling after isolation is of high interest” (Introduction). Steinbrueck teaches the combination of MACS technology, a method for the isolation of functional viable cells with REAlease Technology which leads to the removal of superparamagnetic beads and antibody fragments (Introduction). Steinbrueck teaches using CD4 and CD8 as markers for cell separation, allowing for isolation of cell populations from a single sample (Introduction). As evidenced by Miltenyi Biotech YouTube Video, REAlease technology uses enzymes to disrupt antibody association (see screen capture below, 8:38 – 9:00).
[AltContent: textbox ([img-media_image1.png]
Screen captures from YouTube video clip entitled " How to get label-free cells after cell sorting [WEBINAR]," uploaded on Dec 10, 2018 by user "Miltenyi Biotec". Retrieved from Internet: <http://www.youtube.com/watch?v=3_ukq-9SMjc&t=325s>.)]
Regarding claim 1 step c and claim 4, Steinbrueck teaches the magnetic separation of target cells labeled by a method comprising labeling of target cells with antibodies conjugated with biotin and anti-biotin magnetic beads, column based magnetic separation, and the addition of a reagent that removes the antibody from labeled cells (Figure 1). This process allows for multiple rounds of labeling and obtaining a pure sample (Section 3). Steinbrueck the positive selection of a target cell type followed by the positive selection of another target cell type from the first negative cell fraction. The use of REAlease MicroBeads for both separation steps results in two label-free cell populations of CD4+ and CD8+ cells (Section 4, figure 4).
Jensen does not teach modulatory agents comprising a directly or indirectly coupled chemically cleavable and/or enzymatically degradable linker to beads or nanostructures linking an antibody or antigen binding fragment thereof specific for CD3 and an antibody or antigen binding fragment thereof specific for CD28 or the removal of removing said modulatory agents by chemical and/or enzymatical disruption of said antibodies or antigen binding fragments thereof specific for CD3 or CD28 followed by at least one wash step.
However, regarding, claims 1 and 5, Miltenti teaches a method of cell sorting wherein colloidal superparamagnetic particles bound to a cell surface can be released through action of a glucosidase enzyme which digests a glycosidic linkage present between magnetic particles with antibodies or antigen binding fragments thereof (¶0013-0015, ¶0030-0033). Miltenti further teaches that the use of a glucosidase enzyme allows for rapid release of particles of interest and importantly, it does not alter substantially the surface antigens present on a cell because glucosidase enzyme specifically targets a glycosidic linkage not present on the surface of mammalian cells (¶0023, ¶0028-0029).
Regarding claim 14, Jensen teaches a closed-system manufacturing process for CAR-T cells (Abstract).
Jensen, Steinbrueck, and Miltenti are considered to be analogous to the claim invention because they aim to isolate cells. Steinbrueck teaches that 1) CD4+ and CD8+ cells can be enriched and be positively selected for using a composition comprising a magnetic bead and an antibody directed towards the cell surface antigens, 2) the antibody used in the method can be directed to different surface antigens, and 3) an enzymatic reaction can disrupt the antibody-antigen binding as well as the antibody magnetic bead binding (Figure 1, Figure 4). Miltenti teaches that glycosidic linkages between the magnetic particle and the antibody allow the use of an enzyme to rapidly release the magnetic bead while preserving the integrity of a cell’s membrane (¶0013-0015).
Therefore, it would have been prima facie obvious before the effective filing date of the claimed invention to modify the method taught by Jensen to first sort CD4 and CD8 T cells using the positive cell selection method taught by Steinbrueck because doing so would not only result in high purity CD4 and CD8 T cells but it would allow for further downstream use of magnetic particles, thereby allowing for continued downstream processes. It would have also been prima facie obvious before the effective filing date of the claimed invention to modify the method taught by Jensen to include a enzymatically degradable linker to the magnetic beads, as taught by Miltenti, because doing so would rapidly remove the magnetic particle for downstream processes while maintaining cell integrity. One of ordinary skill in the art would have had a reasonable expectation of success in modifying the method of Jensen given that the positive selection of CD4 and CD8 T cells and the use of enzymatically degradable compositions comprising antibodies and magnetic beads is well known, has been successfully demonstrated, and commonly used in the prior art.
Accordingly, the claimed invention was prima facie obvious to one of ordinary skill in the art at the time of filing especially in the absence of evidence to the contrary.
Claim(s) 2 and 3 are rejected under 35 U.S.C. 103 as being unpatentable over Jensen, Steinbrueck, and Miltenti as applied to claim 1, 4, 5, and 12 above, and further in view of Kaiser et al (WO2015162211A1, hereinafter, “Kaiser”).
As discussed above, claims 1, 4, 5, and 14 were rendered prima facie obvious by Jensen, Steinbrueck, and Miltenti. While the references teach a method of generating modified T cells, the references fail to teach a beginning sample of step a) comprised of human serum and wherein said serum is removed in step b) wherein the enriched T cells of step c) are further depleted of cancer cells by using a tumor associated antigen (TAA) as a negative selection marker.
However, Kaiser teaches a method for automated generation of genetically modified T cells (Title). Kaiser teaches a process for generation of genetically modified T cells, T cell subsets and/or T cell progenitors comprising the steps:
a) providing a cell sample comprising T cells, T cell subsets and/or T cell progenitors
b) preparation of the cell sample by centrifugation
c) magnetic separation of the T cells, T cell subsets and/or T cell progenitors
d) activation of the enriched T cells, T cell subsets and/or T cell progenitors using modulatory agents
e) genetic modification of the T cells, T cell subsets and/or T cell progenitors
f) expansion of the genetically modified T cells, T cell subsets and/or T cell progenitors in a cultivation chamber and
g) washing of the cultured T cells, T cell subsets and/or T cell progenitors characterized in that all steps are performed in a closed and sterile cell culture system (Abstract).
Regarding claim 2, Kaiser teaches wherein the sample of step a) comprises human serum and wherein said serum is removed in step b) (Page 1 lines 8 – 15, Page 22, Example 1).
Regarding claim 3, Kaiser teaches the depletion of cancer cells by using a tumor associated antigen (TAA) as a negative selection marker (Page 7, ¶2).
Jensen, Steinbrueck, Miltenti, and Kaiser are considered to be analogous to the claim invention because they aim to isolate cells. Therefore, it would have been prima facie obvious before the effective filing date of the claimed invention to modify the method taught by Jensen to first being with human serum, as taught by Kaiser, to sort CD4 and CD8 T cells using the positive cell selection method taught by Steinbrueck and the negative selection taught by Kaiser because doing so would not only result in high purity CD4 and CD8 T cells but also ensure the removal of potentially harmful cells. One of ordinary skill in the art would have had a reasonable expectation of success in modifying the method of Jensen given that the positive selection of CD4 and CD8 T cells and the negative selection of cancer cells is well known, has been successfully demonstrated, and commonly used in the prior art.
Accordingly, the claimed invention was prima facie obvious to one of ordinary skill in the art at the time of filing especially in the absence of evidence to the contrary.
Claim(s) 12 is rejected under 35 U.S.C. 103 as being unpatentable over Jensen, Steinbrueck, and Miltenti as applied to claim 1, 4, 5, and 12 above, and further in view of Lu et al (Hum Gene Ther Methods, 2016, 10.1089/hgtb.2016.120, hereinafter, “Lu”).
As discussed above, claims 1, 4, 5, and 14 were rendered prima facie obvious by Jensen, Steinbrueck, and Miltenti. While the references teach a method of generating modified T cells, the references fail to teach removal of residual lentiviral vector particles is performed by incubation with substances that inactivate lentiviral vector particles and/or reduce their stability.
However, Lu teaches a method for the production of engineered autologous CAR-T cell therapies (Title). Lu teaches the motivation to streamline and optimize production to scale for commercial T cell production (Abstract). Lu teaches improvements such as a closed system comprised of removing human serum from the process in order to minimize the risk of viral contamination to generate CD19 CAR-T cells that are phenotypically and functionally indistinguishable from cells produced for clinical trials by the previous methods in 6 days (Abstract).
Lu teaches a method for generation of genetically modified T cells in a closed system comprising the following steps (Abstract):
a) providing a sample, said sample comprising T cells (page 210, column 2, ¶ 1, 2)
b) preparing said sample by centrifugation (page 210, column 2, ¶ 1, 2)
c) isolating lymphocytes of step b using the Sepax II or a manual Ficoll gradient (enrichment of the T cells, as recited in claim 1) (page 211, column 2, ¶ 2, Fig. 5)
d) activating of the enriched T cells using anti-CD3 antibody, OKT3 (modulatory agents, as recited in claim 1) (page 210, column 1, ¶ 3, Fig. 5)
e) genetic modifying of the activated T cells by transduction with retroviral vector PG13-CD19-H3 (page 212, column 1, ¶ 2, Fig. 1, 4, 5)
f) washing of the T cells (removal of said modulatory agents, thereby generating a sample of genetically modified T cells, as recited in claim 1) (page 210, column 2, ¶ 1, 2, Fig. 5)
wherein the method is performed in 6 days (equal or less than 144 hours, as recited in claim 1) (Abstract, Fig. 5).
Regarding claim 12, Lu teaches a step of the viral particles are incubated alongside retronectin which binds directly to retroviral particles thereby blocking transduction (by incubation with substances that inactivate lentiviral vector particles and/or reduce their stability, as recited in claim 12). (page 214, column 1, ¶ 1).
Jensen, Steinbrueck, Miltenti, and Lu are considered to be analogous to the claim invention because they aim to isolate cells. Therefore, it would have been prima facie obvious before the effective filing date of the claimed invention to modify the method taught by Jensen to remove and neutralize retroviral particles, as taught by Lu because doing so would ensure that patients receiving the genetically modified T cells would not be at risk of retroviral infection. One of ordinary skill in the art would have had a reasonable expectation of success in modifying the method of Jensen to remove and/or neutralize retroviral particles given that the removal and/or neutralization of retroviral particles is well known, has been successfully demonstrated, and commonly used in the prior art.
Accordingly, the claimed invention was prima facie obvious to one of ordinary skill in the art at the time of filing especially in the absence of evidence to the contrary.
Claim(s) 13 is rejected under 35 U.S.C. 103 as being unpatentable over Jensen, Steinbrueck, and Miltenti as applied to claim 1, 4, 5, and 12 above, and further in view of Lu and Kaiser.
As discussed above, claims 1, 4, 5, and 14 were rendered prima facie obvious by Jensen, Steinbrueck, and Miltenti. While the references teach a method of generating modified T cells, the references fail to teach removal of human serum or isolated substances therefrom that inhibit productive transduction of lentiviral vector particles to T cells is added to the genetic modified T cells, thereby removing and/or neutralizing residual lentiviral vector particles.
Regarding claim 13, as indicated above, Lu teaches a step of the viral particles are incubated alongside retronectin which binds directly to retroviral particles thereby blocking transduction (by incubation with substances that inactivate lentiviral vector particles and/or reduce their stability, as recited in claim 12). (page 214, column 1, ¶ 1). Kaiser teaches wherein the sample of step a) comprises human serum and wherein said serum is removed in step b) (page 22, Example 1). Kaiser further teaches a step wherein the transduced T cells are re-buffered in a solution suitable for human infusion (page 22, Example 1). Furthermore, Lu teaches a step wherein human serum albumin (HSA) is added to the transduced T cells (page 210, column 2, ¶ 2; Fig. 5). As such, Kaiser and Lu reasonably encompass removing and/or neutralizing residual lentiviral vector particles.
Jensen, Steinbrueck, Miltenti, Kaiser, and Lu are considered to be analogous to the claim invention because they aim to isolate cells. Therefore, it would have been prima facie obvious before the effective filing date of the claimed invention to modify the method taught by Jensen to remove and neutralize retroviral particles, as taught by Lu and Kaiser because doing so would ensure that patients receiving the genetically modified T cells would not be at risk of retroviral infection. One of ordinary skill in the art would have had a reasonable expectation of success in modifying the method of Jensen to remove and/or neutralize retroviral particles given that the removal and/or neutralization of retroviral particles is well known, has been successfully demonstrated, and commonly used in the prior art.
Accordingly, the claimed invention was prima facie obvious to one of ordinary skill in the art at the time of filing especially in the absence of evidence to the contrary.
(Previous rejection, withdrawn in view of amendments) Claims 1-5, and 12-14 are rejected under 35 U.S.C. 103 as being unpatentable over Lu, and in view of Kaiser, and Miltenti.
Response to Arguments
Applicant states amendments to the claim overcome the 35 U.S.C. § 112(b) rejection
Applicant’s amendments overcome the 35 U.S.C. § 112(b) rejection. The rejection has been withdrawn.
Applicant states Claims 1-5 and 12-14 are not obvious over Lu, Kaiser, and Miltenti under 35 U.S.C. § 103
Applicant states that the combination of Lu, Kaiser, and Miltenti is due to hindsight reasoning. In view of the amendments, Jensen and Steinbrueck have also been included in the modified 35 U.S.C. § 103 rejection.
Applicant’s arguments have been full considered but are not persuasive.
In response to applicant's argument that the examiner's conclusion of obviousness is based upon improper hindsight reasoning, it must be recognized that any judgment on obviousness is in a sense necessarily a reconstruction based upon hindsight reasoning. But so long as it takes into account only knowledge which was within the level of ordinary skill at the time the claimed invention was made, and does not include knowledge gleaned only from the applicant's disclosure, such a reconstruction is proper. See In re McLaughlin, 443 F.2d 1392, 170 USPQ 209 (CCPA 1971).
Applicant seeks to claim a process of generating genetically modified T cells. Claim 1 is drawn to a series of steps that when systematically completed produce T cells. Each step tackles a single issue in the manufacturing process. The steps can be broadly described as
a) providing a sample
b) preparing a sample by centrifugation
c) enriching CD4 and CD8 T cells
d) activating CD4 and CD8 T cells using modulatory agents
e) transducing CD4 and CD8 T cells
f) removing modulatory agents using chemical and/or enzymatical disruption
As discussed above and previously, Lu teaches a functionally closed system for producing CD 19 CAR-T cells reproducibly in 6 days and the motivation of shortening production time. Lu teaches
providing a sample, said sample comprising T cells (page 210, column 2, ¶ 1, 2)
preparing said sample by centrifugation (page 210, column 2, ¶ 1, 2)
isolating lymphocytes of step b using the Sepax II or a manual Ficoll gradient (enrichment of the T cells, as recited in claim 1) (Lu et al. page 211, column 2, ¶ 2, Fig. 5)
activating of the enriched T cells using anti-CD3 antibody, OKT3 (modulatory agents, as recited in claim 1) (Lu et al. page 210, column 1, ¶ 3, Fig. 5);
genetically modifying the activated T cells by transduction with retroviral vector PG13-CD19-H3 (Lu page 212, column 1, ¶ 2, Fig. 1, 4, 5)
washing of the T cells (removing said modulatory agents, as recited in claim 1f) (Lu page 210, column 2, ¶ 1, 2, Fig. 5). Absent evidence to the contrary, the washing of the T cells taught by Lu serves to remove residual vector particles as well as the modulatory agents. Therefore, Lu already teaches removing the modulatory agents in the washing step.
Kaiser teaches a method for automated generation of genetically modified T cells (Title). Kaiser teaches a process for generation of genetically modified T cells, T cell subsets and/or T cell progenitors comprising the steps:
a) providing a cell sample comprising T cells, T cell subsets and/or T cell progenitors
b) preparation of the cell sample by centrifugation
c) magnetic separation of the T cells, T cell subsets and/or T cell progenitors
d) activation of the enriched T cells, T cell subsets and/or T cell progenitors using modulatory agents
e) genetic modification of the T cells, T cell subsets and/or T cell progenitors
f) expansion of the genetically modified T cells, T cell subsets and/or T cell progenitors in a cultivation chamber and
g) washing of the cultured T cells, T cell subsets and/or T cell progenitors characterized in that all steps are performed in a closed and sterile cell culture system (Abstract).
Both Lu and Kaiser teach closed loop methods of generating genetically modified T cells largely following the same hierarchical process. To produce CD4+ and CD8+ T cells, one of ordinary skill in the art would have been motivated to modify and combine the prior art to suit their needs. One of ordinary skill in the art would have been reasonably motivated to tailor each step to ensure the process is completed as quickly as possible to not only to proceed to quicker downstream processes but to also save production costs.
Applicant has amended claims to now require T cells do not undergo in vitro expansion.
To this end, to avoid in vitro cell expansion taught by Lu and Kaiser and therefore longer production times, one of ordinary skill in the art would have looked to Jensen to produce T cells without an expansion step. Jensen teaches a process with the same hierarchical process as Lu and Kaiser but achieves CD4+ and Cd8+ T cell production without an expansion step. Again, as all three pieces of prior art teach the same hierarchical process with the same goal of producing genetically modified T cells,this alone would have provided one of ordinary skill in the art with a clear teaching, suggestion, and motivation to combine, modify, and/or adapt the prior art to suit the individual’s goal to reduce production time and materials used while better mimicking natural in vivo T cell production. Doing so would not only reduce costs but would also lead to reducing patient wait times for medical treatment.
Applicant also argues that the Examiner has “plucked” an element from Miltenti. Applicant argues that one of ordinary skill in the art “would not have had any reason to” swap”out the modulatory agents (e.g., CD3/CD28 antibodies) taught by Lu and/or Kaiser with the magnetic microparticles of Miltenti” and that “the particles taught by Miltenti were not intended to be used for methods of stimulating T cells.”
When looking at a series of steps, one of ordinary skill in the art would have ascertained the purpose of each individual step i.e. simply providing a sample would not be enough to produce genetically modified T cells but would be a key first step to producing genetically modified T cells. Thus, each step would be improved towards the goal of the step at hand. If the downstream process of the production of genetically modified T cells is to administer the T cells in a subject, one of ordinary skill in the art would want to remove any contaminants and provide a high purity product. This would include the removal of debris including magnetic beads and viral particles (Jensen: Table 1 - Harvest). Lu, Kaiser, and Jensen each teach the use of antibodies conjugated to magnetic beads. Miltenti and Steinbrueck teach a method of removing antibodies and magnetic beads from cells.
Regardless of the original purpose and use of the methods taught by Miltenti and Steinbrueck, one of ordinary skill would have ascertained that the removal of antibodies and beads without comprising the integrity of the cell would be valuable to the process taught by Lu, Kaiser, and Jensen especially under the context of administering the T cells to a subject. One of ordinary skill in the art would have had a reasonable expectation of success in modifying the method of Jensen with the enzymatically degradable beads taught by Steinbrueck and Miltenti given the use of enzymatically degradable compositions comprising antibodies and magnetic beads is well known, has been successfully demonstrated, and commonly used in the prior art.
Together, Jensen, Steinbrueck, Miltenti, Lu, and Kaiser are not “disparate teachings.” Accordingly, the claimed invention was prima facie obvious to one of ordinary skill in the art at the time of filing especially in the absence of evidence to the contrary.
Conclusion
NO CLAIMS ARE ALLOWED
Pertinent art to the applicant but not relied upon:
Davis et al (US20120045828A1)
Pezzi et al (ACS Omega, 2018, 10.1021/acsomega.7b01427)
Werther et al (J Immunol Methods, 2000, 10.1016/s0022-1759(00)00150-2)
Praja et al (Researchgate, February 2019, https://www.researchgate.net/post/Are_there_any_methods_to_remove_the_antibody_binding_after_cell_sorting)
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Danyal H Alam whose telephone number is (571)272-1102. The examiner can normally be reached M - F 9am - 5pm.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Thomas J. Visone can be reached at 571-270-0684. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/DANYAL HASSAN ALAM/Examiner, Art Unit 1672
/THOMAS J. VISONE/Supervisory Patent Examiner, Art Unit 1672
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