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 .
Applicant’s remarks, filed 5/27/2025, are acknowledged and entered into the record. Applicants amended claim 49 in the remarks of 5/27/2025; no additional claims have been added or canceled.
Priority
Applicant’s claim for the benefit of a prior-filed application under 35 U.S.C. 119(e) or under 35 U.S.C. 120, 121, 365(c), or 386(c) is acknowledged. The present application is drawn from PCT/US2020/020539, filed 2/28/2020; and claims benefit under 35 U.S.C. 119(e) to U.S. Provisional application 62/812908, filed 3/1/2019.
Election/Restrictions
Applicant’s election without traverse of Group III, encompassing claims 33-34 and 36-52, in the reply filed on 12/19/2024 is acknowledged. Applicants canceled claims 3-4, 6-12, 14, 21-22, 24, 26 and 28, and added new claims 38-52, in the reply of 12/19/2024. Claim 1 is withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected Group I, there being no allowable generic or linking claim. Election was made without traverse in the reply filed on 12/19/2024.
Status of Claims
Claims 1, 33-34 and 36-52 are pending, claims 33-34 and 36-52 are being examined on the merits.
Claim Rejections - Maintained
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.
Claims 33 and 47-52 are rejected under 35 U.S.C. 103 as being obvious over Ingato et al., (from IDS; ACS Nano, 2018, 12) and Klingemann (from IDS; US 2004/0022773; published 2/5/2004).
Ingato et al. teaches cancer cell-derived, drug-loaded nanovesicles induced by sulfhydryl-blocking for effective and safe cancer therapy (title). Specifically, Ingato teaches generation of extracellular vesicles for their use as therapeutic carriers (abstract). Ingato teaches “here we overcome these setbacks by preparing cell-derived nanovesicles induced by sulfhydryl-blocking, in the desirable size range for therapeutic delivery, that can be further loaded with the chemotherapeutic drug, doxorubicin (DOX).” Further, “applicable to most cell types, this chemical blebbing approach enables efficient, quick, and simple harvest and purification as well as easily scalable production,” (abstract). Ingato applied the produced extracellular vesicles as a therapeutic treatment for cancer in a tumor-challenged mouse model (abstract). In practicing the method to produce the extracellular vesicles, Ingato applies the sulfhydryl-blocking agent paraformaldehyde (pg. 9569, Fig. 1). Ingato teaches that nanovesicles induced by sulfhydryl-blocking (NIbS) is applicable to “most cell types”, including NK cells (pg. 9569, col. 2 – pg. 9570, col. 1). However, Ingato does not specifically apply the method of producing extracellular vesicles to human NK92 cells.
Klingmann teaches utilizing a maintained NK cell line comprising NK-92 cells, whereby the NK cells may be modified by various techniques to confer advantageous properties, and wherein the cells may be used in methods of purging cancer cells in a biological sample or treating cancer in vivo (abstract; pg. 1, para. 0002). NK-92 cells are known in the art as a human cell line of NK cells derived from a patient with non-Hodgkin’s lymphoma (see, for example, instant specifications pg. 2, para. 0006). Given the safety and ability of NK-92 cells to treat cancer, it would have been obvious to a person of ordinary skill in the art to utilize NK-92 cells in the method taught by Ingato.
It would have been obvious to one of skill in the art to modify the method of inducing extracellular vesicles by application of a sulfhydryl blocking agent, as taught by Ingato et al., to be applied to NK-92 cells. One would have been motivated to do so given the knowledge that cell-derived nanovesicles, induced by sulfhydryl-blocking, may be a desirable therapeutic for treatment of cancer, as taught by Ingato et al. There would have been a reasonable expectation for success given that the generation of extracellular vesicles by application of a sulfhydryl-blocking agent is applicable to most cell types, as taught by Ingato et al.; and that NK-92 cells are a safe and reliable cell line for treating cancers, as taught by Klingmann et al. Thus, the invention as a whole was prima facie obvious to one of skill in the art at the time the invention was made.
Regarding claims 33, 49 and 51, Ingato teaches administration of nanovesicles induced by sulfhydryl-blocking (NIbS), which were loaded with the cancer therapeutic doxorubicin (DOX; re. claim 49), were administered to EL4-tumor-bearing mice (pg. 9573, col. 1, para. 1; pg. 9572, Figure 6), via intravenous injection (re. claim 51). Thus, the combination method of Ingato and Klingmann makes obvious a method of treating a subject with cancer comprising administering NK EVs of instant claim 33.
Regarding claims 47-48, 50 and 52, the combination method of Ingato and Klingmann is described above. Klingmann teaches the use of immortalized human NK-92 cells, and thus makes obvious claim 47. Ingato teaches that NIbS are on average 30 nm in diameter (pg. 9570, col. 2, para. 2; Fig. 2A), and thus makes obvious claim 48. Klingmann teaches NK-92 cells can be used to treat pathologies such as cancers, including leukemia (pg. 3, para. 0017), and thus makes obvious claim 50. Klingmann also teaches that the therapeutic NK agents may be injected directly within or adjacent to a solid tumor (pg. 8, para. 0069), and thus makes obvious instant claim 52.
Response to Arguments
Applicant's arguments filed 5/27/2025 have been fully considered but they are not persuasive. Applicants contend that Ingato teaches nanovesicles induced by sulfhydryl-blocking (NIbS) require being further loaded with a chemotherapeutic drug in order for their use as an anti-tumor agent in a method of treating cancer (remarks, pg. 7, para. 3). Further, applicants contend that blank NIbS were ineffective at prolonging survival of animals with cancer (pg. 7, pg. 8, Fig. B). That Klingmann teaches the clinical use of NK cells for immunotherapy, however, that Klingmann teaches some disadvantageous properties of NK cells for in vivo uses, including requiring patients to be co-treated with IL-2 (pg. 8, last paragraph), and the difficulty in working with NK cells and expanding NK cells ex vivo that maintain their tumor-targeting properties in vivo, (pg. 9, para. 2). Applicants highlight that the clinical methods for using NK cells do not require the cells to be treated in the manner of Klingmann (pg. 10, paras. 1-2). Thus, applicants contend that the NK ICVs of the instant invention do not have to be loaded with a chemotherapeutic, unlike the NIbS taught in Ingato, to reduce cancer viability; and that the NK ICVs do not have to be modified in the manner of Klingmann to find use as a cancer treatment (pg. 10, para. 3). Thus, applicants contend that the cited art teachings would not make the claimed invention obvious as there is nothing to suggest that NK ICVs would be effective by themselves in reducing cancer cell viability, or that the NK ICVs derived from the NK cells of Klingmann would necessarily comprise the properties for reducing cancer viability, such as producing cytokines and the like (pg. 10, para. 4).
In response the examiner will cite three points of contention with the applicant’s arguments; 1) applicants provide a piecemeal analysis of the references individually, and not their combination; 2) that the ineffective “blank NIbS”, of Ingato, are not an appropriate comparison to blank NIbS derived from NK cells; and 3) that the claims are not limited in scope to exclude additional features taught in the references. First, in response to applicant's arguments against the references individually, one cannot show nonobviousness by attacking references individually where the rejections are based on combinations of references. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981); In re Merck & Co., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986). The rejection over Ingato and Klingmann is in their combination; that is, applying the method of producing NIbS (of Ingato) from NK cells (of Klingmann). As described above, Ingato specifically points out that the method may be applied to NK cells. As NK cells have innate anti-tumor properties, it is reasonable to expect that vesicles derived from the NK cells would also have innate anti-tumor properties, and thus not need an additional therapeutic. For example, the cited reference of Jong et al. teaches isolating EVs from activated NK cells, and demonstrates that the NK cell EV were in fact cytotoxic to various cancer cell lines (see Jong, below). As it was known in the art that NK cell EVs could have innate cytotoxic properties against cancer cell lines, the skilled artisan could apply the method for producing NIbS, of Ingato, to the human NK-92 cells of Klingmann, and have a reasonable expectation for success that the resulting NK ICVs would have innate anti-tumor properties, given that NK cells have innate anti-tumor properties. Nothing in either Ingato nor Klingmann explicitly teach away from this reasonable expectation based on common knowledge in the prior art. While Klingmann highlights some considerations when attempting to use whole NK cells for in vivo cancer treatment; Klingmann does not consider these additional conditioning steps a barrier to their use, as the invention of Klingmann is the use of NK cells, in vivo, in a method for treating cancer (see Klingmann, pg. 20, claims 20 and 22). The mere possibility that a method may not work does not make unexpected the finding that it does without identifying the specific structural differences that defy the expectation for success. Given the teachings of Jong, that NK EVs are cytotoxic to cancer cells, there was a reasonable expectation for success that alternative NK EVs (i.e. NK NIbS) would work in a similar fashion.
Second, the teachings of Ingato, that the “blank NIbS” had no cytotoxic effect is not an appropriate comparison to the NK cell-derived NIbS of the instant invention. The combination of Ingato and Klingmann rely on NK cells as the cells from which the NIbS were derived. It is known in the art that NK cells have innate anti-tumor properties, hence their name “Natural Killer” cells, and do not have to be loaded with an additional cytotoxic agent. Therefore, in order to persuade an artisan that “blank NIbS”, in general, are ineffective against tumor cells, the comparison requires that the blank NIbS are derived across various cell types, including NK cells, for comparison, rather than NIbS isolated from a single non-NK cell type. Indeed the use of NK cells, in the combination of Ingato and Klingmann, is motivated by the specific therapeutic potential of NK cells over alternative cell types, as taught by Klingmann. Conversely the “blank NIbS” of Ingato are derived from T cell lymphoma EL4 cells, and then used to treat EL4 tumors (Ingato, pg. 9570, col. 1, para. 2; Fig. 6). Therefore, it is unsurprising that blank NIbS derived from EL4 cells would have innate cytotoxicity against EL4 tumors; rather, they would likely require the addition of a cytotoxic modality to impart cytotoxic properties. However, this may or may not apply to other cell types from which NIbS are derived, or their cytotoxicity against various other cancer cell types, as NK cells are known in the art to have innate cytotoxic properties against various cancer cell types. It is inappropriate to generalize the lack of cytotoxic effect of the specific blank EL4 NIbS, against EL4 tumors, of Ingato, as being an expected property of all blank NIbS generated from any cell type. Thus the reference to the inability of “blank NIbS” derived from EL4 cells to reduce tumor growth (of the same tumors from which they were derived) in animal models is not relevant to the use of NIbS derived from NK cells, as in the combination of Ingato and Klingmann.
Third, in response to applicant's argument that the references show certain features that are not included in the invention, it is noted that the features upon which applicant relies are not recited, nor excluded, in the rejected claims. Although the claims are interpreted in light of the specification, limitations from the specification are not read into the claims. See In re Van Geuns, 988 F.2d 1181, 26 USPQ2d 1057 (Fed. Cir. 1993). Thus, while Ingato teaches that the NIbS are loaded with an additional therapeutic agent, claim 33 does not exclude the use of additional therapeutics loaded onto the NIbS. The instant specifications, in describing the NK ICVs of the instant invention, recite that “the NK ICVs disclosed herein may be used to encapsulate a biological molecule, such as…therapeutic agents, such as drug products like chemotherapeutic agents, etc.,” (specs, pgs. 7-8, para. 0030). Similarly, while the extra conditioning steps of Klingmann, regarding administration of whole NK cells in vivo, may or may not be necessary for delivery of the NK NIbS of Ingato and Klingmann, such additional steps are encompassed in the broad scope of the claims. That is, none of the instant claims recite wherein such additional conditioning steps are explicitly excluded from the instant methods comprising administering a therapeutically effective amount of a pharmaceutical composition comprising NK ICVs to a subject with cancer in need thereof. Thus, as administering blank NK NIbS would have a reasonable expectation for success as a cancer therapeutic, as there is no teaching away or relevant demonstration that the blank NK NIbS would be ineffective against cancer cells, and as the scope of the claims encompass (optional) additional conditioning steps for NK cells and/or addition of therapeutic agents to the NK cell-derived NIbS, applicants arguments are found unpersuasive, and the rejection of claims 33 and 47-52 over the combination of Ingato and Klingmann is maintained.
Claim Rejections - Maintained- 35 USC § 103
Claims 33-34 and 48-52 are rejected under 35 U.S.C. 103 as being unpatentable over Jong et al., (J. of Extracellular Vesicles; 2017, (6)) and Bauer et al., (from IDS of 6/22/2022, Cite No. 4; US 2011/0143385, published 6/16/2011) and Selaru et al., (US 2018/0028687; published 2/1/2018).
Jong et al. teaches the large-scale isolation of extracellular vesicles (EVs) derived from activated human natural killer (NK) cells (title). Jong teaches that extracellular vesicles are secreted by all cell types including NK cells and may play important roles in the immune system. Jong teaches that the term EVs applies to exosomes, microvesicles and apoptotic bodies which are released by cells in in vitro culture medium, and that microvesicles are formed by outward budding of the plasma membrane (pg. 1, col. 1, para. 1). Jong teaches that EVs contain specific proteins depending on the cell of origin, for example, EVs form tumor cells contain tumor antigens; EVs may contain microRNAs and mRNAs; and EVs can be used as devices for communication via the direct exchange of proteins and RNA between cells (pg. 1, last paragraph – pg. 2). Jong teaches a simple, robust and cost-effective method to isolate a large quantity of NK EVs, and demonstrates that the isolated EV fractions were cytotoxic against cancer cells, whereby they may be used in clinical applications (abstract). Jong teaches that NK cells are innate immune effector cells that induce cytotoxicity upon stimulation, and are being evaluated for cell-based cancer treatment; and that human NK cells release EVs that contain typical NK cell markers and proteins, thus raising the possibility the EV-based delivery of cytotoxic molecules might be exploited as an entirely new approach to treat cancer (pg. 2, col. 2, para. 1). Jong teaches a method of activating NK cells with co-incubation with PBMCs, culturing the NK cells in an exosome-free FBS, collecting the conditioned medium after 48 hours, filtrating the cell-free conditioned medium and precipitating a final concentration of EVs (pg. 5, col. 2, Results, para. 1). Jong teaches the majority of the NK EVs were in the range of 50-200 nm (pg. 6, col. 1, para. 1; pg. 5, Fig. 2b). Jong teaches that the NK EVs were cytotoxic to cancer cell lines including lymphoblastic leukemia and neuroblastoma cells (pg. 7, col. 1, para. 1; pg. 8, Fig. 4). Jong concludes, “thus, the scale-up isolation procedure resulting in aNK EVs with efficient cytotoxic activity lays the foundation for the future development of new anti-cancer therapeutics,” (pg. 10, col. 2, para. 1). Thus, Jong teaches the art of isolated NK cell vesicles for use in a method to treat cancer. However, Jong does not teach wherein the NK EVs are induced, nor does Jong teach a method of administering the EVs for treating cancer in a subject in need thereof.
Bauer et al. teaches the art of plasma membrane vesicles and methods of making and using the same (title, abstract). Bauer teaches methods for producing plasma membrane vesicles comprising contacting a cell with a vesiculation agent, thereby producing plasma membrane vesicles (pg. 1, para. 0006; pg. 16, claim 1). Bauer teaches the cells are mammalian cells, e.g., human cells (pg. 1, para. 0007; pg. 16, claim 5). Bauer teaches the vesiculation agent comprises a sulfhydryl blocking agent, e.g., is formaldehyde, DTT, etc. (pg. 1, para. 0008; pg. 16, claims 6 and 8). Bauer teaches the method further comprises purifying the plasma membrane vesicles by any one or more of filtering, centrifugation or dialysis (pg. 2, para. 0013; pg. 17, claim 14). Bauer teaches wherein the plasma membrane vesicles comprise transmembrane proteins, such as receptors, and wherein the membrane proteins are anchored proteins (pg. 17, claims 22 and 24-25). Thus, Bauer teaches that application of a sulfhydryl blocking agent to the culture buffer may induce plasma membrane vesicles.
It would have been obvious to one of skill in the art to modify the methods of isolating EVs derived from NK cells of Jong et al. to include a step of contacting the cells with sulfhydryl blocking agent. One would have been motivated to do so given that application of a sulfhydryl blocking agent induces the generation of more EVs as taught by Bauer et al., and that generation of a large quantity of EVs would be beneficial for use as a therapeutic as taught by Jong et al. There would have been a reasonable expectation for success given that the method of applying a sulfhydryl blocking agent for inducing EVs may be applied to make plasma membrane vesicles from any cell type as taught by Bauer et al.
Thus, the combination of Jong and Bauer make obvious a method for producing and isolating NK cell “induced” cellular vesicles, whereby Jong teaches the NK EVs are cytotoxic to cancer cells and may be useful as a therapeutic for cancer. However, the combination of Jong and Bauer do not teach administering a pharmaceutical composition of EVs to a subject with cancer in need thereof.
Selaru et al. teaches the art of extracellular vesicles, including compositions comprising extracellular vesicles and methods of using such compositions for therapeutics (pg. 1, para. 0002). Selaru teaches the present invention provides EVs derived from a cancer associated cell, comprising an exogenous agent, whereby the agent may be a polypeptide and methods of using such EVs (pg. 1, para. 0004; pg. 21, claim 5). Selaru teaches the agent polypeptide may be a recombinant polynucleotide that is heterologously expressed in the cell or is loaded into the cell ex vivo (pg. 1, para. 0007; pg. 21, claim 7); and that an exogenous agent is one that is not naturally occurring in the cell, such as a protein that is recombinantly expressed (pg. 4, para. 0041). Selaru teaches the extracellular vesicle may be isolated from cancer cells, tumor-associated cells, or from bodily fluid selected from, for example, lymphatic drainage or pancreatic secretions (pg. 1, para. 0007). Selaru teaches the vesicle is isolated from mammalian cells and the vesicle is a microvesicle or exosome (pg. 1, para. 0007, last two sentences). Selaru teaches that microvesicles have a diameter of between 10 nm and 5000 nm (pg. 5, para. 0057). Selaru teaches that the invention provides EVs comprising proteins which may induce the death of infected or deficient cells, including recombinant polypeptides encoding said proteins and their expression in a suitable host cell from which the EVs are derived (pg. 10, para. 0115), or whereby the isolated polypeptides are loaded into EVs as described, for example, for antibody delivery (pg. 10, paras. 0123-0124). Selaru teaches that in general, the physical properties of the EVs of the invention are sufficient to target the EV to a cancer cell of interest, for example breast cancer or glioblastoma (pg. 12, para. 0141). Selaru teaches methods of formulation are well known in the art (pg. 13, para. 0144); and that the EVs of the invention may be formulated in pharmaceutical compositions (pg. 13, para. 0142; pg. 21, claim 41), and may be administered via any appropriate route of administration, including parenterally, intravenously, or intratumorally (pg. 13, para. 0143), including injection to the site of neoplasia (pg. 14, para. 0152). Selaru teaches the formulations can be administered to human patients in therapeutically effective amounts to provide therapy for a disease or condition (pg. 13, para. 0145); and includes a neoplastic disease (pg. 13, para. 0146; pg. 21, claim 21). Thus, Selaru teaches methods of administering a therapeutically effective composition of EVs, which may or may not comprise an exogenous protein (i.e. a CAR), for the treatment of cancer.
It would have been obvious to one of skill in the art to administer a pharmaceutical composition comprising the NK EVs of Jong and Bauer in a method to treat cancer in a subject in need thereof. One would have been motivated to do so to provide therapy to a subject suffering from a cancer. There would have been a reasonable expectation for success given that the NK EVs of Jong are cytotoxic to cancer cells in vitro, and that EVs can be formulated into pharmaceutical compositions and administered to humans suffering from cancer, as taught by Selaru et al. Thus, the invention as a whole was prima facie obvious to one of skill in the art at the time the invention was made.
Regarding claims 33-34, the combination of Jong, Bauer and Selaru makes obvious a method of generating induced cellular vesicles from NK cells and administering them to a subject in need thereof as a treatment for cancer (re. claim 33), as described above. Further, Jong teaches the NK EVs may be prepared from individual patients for autologous use (pg. 10, col. 1, para. 2); and thus makes obvious instant claim 34.
Regarding claim 48, Jong teaches that the isolated NK EVs are microvesicles with a diameter in the range of 50-200 nm (pg. 6, col. 1, para. 1; pg. 5, Fig. 2b), and therefore makes obvious claim 48.
Regarding claim 49, Selaru teaches that administration of EVs for use to slow the spreading of the cancer, slow the cancer’s growth, to kill or arrest cancer cells that have spread to other parts of the body, to relieve symptoms caused by the cancer, or to prevent cancer in the first place, may be combined with conventional therapies, including therapies for the treatment of proliferative disease, such as chemotherapy (pg. 14, para. 0152). Thus, the combination method of Jong, Bauer and Selaru makes obvious instant claim 49.
Regarding claim 50, Jong teaches that the NK EVs are cytotoxic to lymphoblastic leukemia cells as well as CHLA-255 neuroblastoma cells (pg. 7, col. 1, para. 1), and thus makes obvious the method of Jong, Bauer and Selaru for treating a subject with a cancer selected from leukemia or glioblastoma of instant claim 50.
Regarding claims 51-52, the combination method of Jong, Bauer and Selaru is described above. Selaru teaches administration of a composition of EVs may be intravenously (pg. 13, para. 0143) or intratumorally (pg. 14, para. 0152), and thus makes obvious instant claims 51 and 52.
Claims 36-47 are rejected under 35 U.S.C. 103 as being unpatentable over Jong et al., (J. of Extracellular Vesicles; 2017, (6)) and Bauer et al., (from IDS of 6/22/2022, Cite No. 4; US 2011/0143385, published 6/16/2011) and Selaru et al., (US 2018/0028687; published 2/1/2018) as applied to claims 33-34 and 48-52 above, and further in view of Wels et al., (US 20170129967; published 5/11/2017).
The combination method of Jong, Bauer and Selaru, comprising isolating NK EVs (Jong), which were induced by a sulfhydryl blocking agent (Bauer), for administration (Selaru) in a method to treat cancer, is described above. However, the applied references do not teach wherein the NK cells express a chimeric antigen receptor (CAR).
Wels teaches CAR-expressing NK-92 cells a cell therapeutic agents (title). Wels teaches NK cells are important effector cell type for adoptive cancer immunotherapy; and that similar to T cells, NK cells can be modified to express CARs to enhance antitumor activity (pg. 1, para. 0002). Wels teaches the benefit of the invention being “in contrast to T cells, NK cells do not require prior sensitization and recognition of peptide antigens presented in complex with MHC molecules; instead, NK cell cytotoxicity can be triggered rapidly upon appropriate stimulation through germline-encoded cell surface receptors (pg. 1, para. 0003). Wels teaches the present invention aims to provide improved CAR-engineered NK cells, which are suitable for clinical use, in particular in the treatment of cancers and as targeted cell therapeutic agents (pg. 1, para. 0005). Wels teaches that the inventors redirected clinically usable human NK-92 cells to the tumor associated ErbB2 (HER2) antigen using the anti-ErbB2 CAR of the invention (pg. 5, para. 0050), although other CARs are suitable as well (pg. 5, para. 0048). Wels teaches that the CAR-NK cells were derived from a single cell clone after lentiviral transduction with a vector encoding a second generation CAR that targets the ErbB2 (HER2) receptor tyrosine kinase, a tumor-associated self-antigen expressed at elevated levels by many human cancer of epithelial origin (pg. 8, para. 0169). Wels describes the codon-optimized fusion gene was synthesized and inserted into a lentiviral transfer plasmid vector resulting in lentiviral transfer plasmid pS-5.28.x-W, and NK-92 cells were transduced as described previously (pg. 10, para. 0196), thus Wels teaches use of a vector to genetically modify cells to express a CAR (pg. 21, claim 12). Wels teaches the cancers targeted by the ErbB2 CAR NK cells include breast cancer, lung cancer and glioblastoma (pg. 8, para. 0148; pg. 21, claim 9); and treatments comprises administering a therapeutically effective amount of the CAR NK cells of the invention (pg. 8, paras. 0165-0166).
It would have been obvious to one of skill in the art to modify the combination method for treating cancers via administration of a composition of induced NK EVs of Jong, Bauer and Selaru to derive the NK EVs from the CAR-expressing NK cells of Wels. One would have been motivated to do so given the knowledge that NK EVs may be altered to improve targeting and cytotoxicity via engineering of the NK cells, as taught by Jong et al. (pg. 10, col. 2, para. 1); and that the ErbB2 CAR can target NK cells to HER2 expressing cancers where they may be cytotoxic to the cancer cells, as taught by Wels et al. There would have been a reasonable expectation for success given that human NK cells naturally release EVs that contain typical NK cell markers and proteins that can induce target cell death, as taught by Jong et al. (pg. 2, col. 2, para. 1). Thus, the invention as a whole was prima facie obvious to one of skill in the art at the time the invention was made.
Regarding claim 36, the combination method of Jong, Bauer and Selaru, using the NK cells of Wels, makes obvious the method of claim 36, as described above.
Regarding claim 37, the combination method of Jong, Bauer, Selaru and Wels is described above, Further, Jong teaches the NK EVs may be prepared from individual patients for autologous use (pg. 10, col. 1, para. 2); and thus makes obvious instant claim 37.
Regarding claims 38-41 and 47, Wels teaches that the CAR-engineered NK-92 cells were developed as a targeted allogenic cell therapeutic agent, thereby making obvious the allogenic NK cells of claim 38, wherein the NK cells are genetically modified to express a CAR of claim 39, and whereby the NK cells are NK-92 cells of claims 40 and 47. Further, Wels teaches the NK cells were genetically modified using a viral vector (pg. 21, claim 12), thereby making obvious instant claim 41.
Regarding claim 42, Jong teaches that the isolated NK EVs are microvesicles with a diameter in the range of 50-200 nm (pg. 6, col. 1, para. 1; pg. 5, Fig. 2b), and therefore makes obvious claim 42.
Regarding claim 43, Selaru teaches that administration of EVs for use to slow the spreading of the cancer, slow the cancer’s growth, to kill or arrest cancer cells that have spread to other parts of the body, to relieve symptoms caused by the cancer, or to prevent cancer in the first place, may be combined with conventional therapies, including therapies for the treatment of proliferative disease, such as chemotherapy (pg. 14, para. 0152). Thus, the combination method of Jong, Bauer, Selaru and Wels makes obvious instant claim 43.
Regarding claim 44, Wels teaches the CAR NK cells may be used to treat HER2 expressing cancers, including breast cancer, lung cancer or glioblastoma (pg. 21, claim 9). Thus, the combination method of Jong, Bauer, Selaru and Wels makes obvious instant claim 44.
Regarding claims 45-46, the combination method of Jong, Bauer, Selaru and Wels is described above. Selaru teaches administration of a composition of EVs may be intravenously (pg. 13, para. 0143) or intratumorally (pg. 14, para. 0152), and thus makes obvious instant claims 45 and 46.
Response to Arguments
Applicant's arguments filed 5/27/2025 have been fully considered but they are not persuasive. Applicants contend that Jong et al. teaches a heterogenous population of extracellular vesicles (EVs), which include exosomes and microvesicles (remarks, pg. 11, para. 2); that the EVs of Jong had differential results compared to NK cell exosomes, specifically; that Jong teaches EVs derived from highly activated allogenic NK cells co-cultured with artificial antigen-presenting cells; and that Jong teaches purification protocols using PEG8000 (remarks, pg. 12, paras. 2, 4 and 6). Applicants contend that Bauer et al. teach their membrane vesicles have a diameter of about 1 uM to about 100 uM (remarks, pg. 13, para. 2); and that Bauer teaches the use of their invention in methods of screening, or reverse screening (remarks, pg. 13, para. 2, 4 and 6), and not for the use as described here. Applicants contend that Selaru et al. teaches EVs produced from cancer associated cells, and not NK cells (remarks, pg. 15, para. 2). Thus, applicants contend that the techniques of Bauer are applied to a broad genus of mammalian cells, were not contemplated in NK cells, or for use as a cancer therapeutic (remarks, pg. 15, para. 5), and that Jong and Selaru do not remedy the deficiencies of Bauer, as they teach EVs which would be compositionally different (i.e. comprising heterogenous types of vesicles and impurities), and whereby the EVs of Selaru require being loaded with an agent (remarks, pg. 17, para. 1). Regarding Wels et al., applicants contend that Wels does not cure the deficiencies of Jong, Bauer and Selaru because there would be no reasonable expectation for success at applying the techniques of Jong to the cells of Wels (remarks, pg. 19, para. 2), and that Wels teaches NK cell-based therapy, which would have severe side effects (remarks, pg. 18, last paragraph).
The examiner contends that the arguments of applicants are based on a piecemeal analysis of the references. In response to applicant's arguments against the references individually, one cannot show nonobviousness by attacking references individually where the rejections are based on combinations of references. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981); In re Merck & Co., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986). Bauer teaches the technique of applying sulfhydryl blocking agents to induce vesicles from cells, as described above. Applicant’s remarks acknowledge that the vesicles of Bauer’s technique are the same as the NK ICVs of the instant claims (and the NIbS of Ingato), but different from the EVs of Jong and Selaru (remarks, pg. 16, para. 1, lines 3-5; pg. 19, para. 2, lines 5-6). While Bauer does not teach NK cells specifically, Bauer teaches the technique may be applied to the broad genus of “mammalian cells”. Bauer does not need to teach the use of the products of their technique, the artisan may find motivation to use the products of Bauer in different methods, such as those contemplated by Jong and Selaru. Thus, the Bauer reference, alone, does not need to provide motivation to be used in alternative methods; the Bauer reference teaches the technique to obtain the sulfhydryl blocking agent-induced vesicles (i.e. NIbS) with a reasonable expectation for success. When combined with the teachings of Jong and Selaru, the products of Bauer’s technique will be NK ICVs, and will be administered in a method of treating cancer using NK EVs as taught by Jong and Selaru, or wherein the NK cells express a CAR, as taught by Wels. Section 2143 of the MPEP provides examples of rationales that may support a conclusion of obviousness, including 2143(I)(A)-combining prior art elements according to known methods to yield predictable results; (B) simple substitution of one known element for another to obtain predictable results; (C) use of a known technique to improve similar methods in the same way; (D) applying a known technique to a known method ready for improvement. Here the combination of Bauer’s technique for inducing cell nanovesicles is combined with the methods of treating cancer using NK cell EVs of Jong or Wels. The use of NK cells in place of, for example EL4 cells (or another non-NK cell), is a simple substitution of known elements for use in the known technique of Bauer. Using the technique of Bauer, to produce nanovesicles, is an improvement on the technique of Jong, which uses NK cell EVs. Thus, substituting the cell type, from which nanovesicles are being induced, of Bauer or Ingato, from non-NK cells to NK cells is not a patentably distinct point of novelty, it is an obvious substitution in view of the methods of Jong, Selaru and Wels. Bauer teaches the method may be used broadly, with mammalian cells; Ingato teaches the method may be used with NK cells specifically, and neither reference teaches away from using NK cells.
Regarding the size, Bauer teaches the isolated vesicles are “about” 1000 nm in diameter, which would include those with 999 nm diameter. Further, the NK cell EVs of Jong are microvesicles in the range of 50-200 nm diameter, as described above; and which may be the same nanovesicles of Ingato, who describes nanovesicles as a subpopulation of EVs in the 30-100 nm size range. Regarding the composition of EVs, Bauer teaches plasma membrane vesicles are known as “blebs”, little bud-like protrusions formed in the outer membrane (see remarks, pg. 13, para. 3). Jong teaches that EVs are heterogenous and include exosomes, microvesicles, and apoptotic bodies released by cells, in vitro, into culture medium (see remarks, pg. 11, last paragraph). Further, Ingato teaches deriving EVs in a size range of 30-100 nm, that cells in culture naturally produce EVs, and that chemically induced EV production could be a promising method for rapid and large-scale production (see Ingato, Introduction, pg. 9568). Ingato teaches “EVs are broadly categorized vesicles including exosomes, microvesicles and apoptotic bodies, with subcategories”; and that “NIbS are solely the product of cell membrane blebbing,” suggesting that NIbS are a subcategory of EVs (see remarks, pg. 16, para. 3). Further, Ingato teaches “NIbS are produced for a significantly shorter period of time in PBS supplemented by PFA and DTT, resulting in a supernatant this is richer in EVs,” (see remarks pg. 16, para. 4). Thus, the teachings of Ingato support that NIbS are a subcategory of EVs, which may be heterogenous, depending on the defining features of the particular vesicles produced. Thus, while the EVs of Jong are heterogenous in their composition, it is reasonable to assume that nanovesicle “blebs” are a naturally occurring subcategory of EVs. The technique of Bauer (or Ingato) comprising a sulfhydryl blocking agent further promotes the production of the nanovesicle subcategory of EVs. As stated above, the instant claims do not exclude other types of EVs in the composition, rather, they comprise nanovesicles, blebs, or NIbS; which according to Ingato are EVs in the 30-100 nm range. While it may be acknowledged that the EVs of Jong are “compositionally different” than the NK ICVs of the instant invention (see remarks, pg. 17, para. 1; pg. 19, para. 2; pg. 20, paras. 1 and 4); it is reasonable to assume that NK EVs comprise nanovesicles, and further that the amount of NK EVs that are nanovesicles would be increased by applying the technique of Bauer (or Ingato). Thus, compositionally heterogenous NK EVs do not teach away from using NK ICVs, rather they comprise NK nanovesicles, which may be further induced (i.e. ICVs) by a sulfhydryl blocking agent. Therefore applicant’s arguments that the EVs are compositionally different, and therefore implying that they are distinct compositions, is not found persuasive. Instead it may be that the EV compositions of Jong are heterogenous, and include a subset of naturally occurring nanovesicles, which may be further amplified using the induction techniques of Bauer, and therefore meet the limitations of instant claim 33, particularly in view of the combination of Jong, Bauer, Selaru and Wels. Regarding the issues such as that the EVs of Jong are co-cultured with other cells, or that they are purified using PEG8000, or that Selaru does not teach EVs derived from NK cells, or that the EVs of Selaru require loading with an additional agent, the examiner points to 1) the combination of references used to arrive at the instant methods, and 2) the claims do not exclude any of the extraneous steps of the applied references. The additional considerations or steps present in each of the references would not prevent, nor exclude, their use in the combination method as applied; that is they don’t teach away or break the invention. The skilled artisan can apply the methods of Bauer to the NK cells of Jong or Wels and/or use the NK cells of Jong or Wels in the therapeutic methods of Selaru. All of the references were in the public domain at the time of the invention, and it would have been obvious to apply the methods of producing nanovesicles, of Bauer, to NK cells, with motivation provided by Jong or Wels, and to use the nanovesicles in a method of treating cancer, as described by Selaru. The applicant’s arguments are not found persuasive and the rejection of claims 33-34 and 36-52 over the combination of Jong, Bauer, Selaru and Wels is maintained.
Claim Rejections – Maintained - Double Patenting
The nonstatutory double patenting rejection is based on a judicially created doctrine grounded in public policy (a policy reflected in the statute) so as to prevent the unjustified or improper timewise extension of the “right to exclude” granted by a patent and to prevent possible harassment by multiple assignees. A nonstatutory double patenting rejection is appropriate where the conflicting claims are not identical, but at least one examined application claim is not patentably distinct from the reference claim(s) because the examined application claim is either anticipated by, or would have been obvious over, the reference claim(s). See, e.g., In re Berg, 140 F.3d 1428, 46 USPQ2d 1226 (Fed. Cir. 1998); In re Goodman, 11 F.3d 1046, 29 USPQ2d 2010 (Fed. Cir. 1993); In re Longi, 759 F.2d 887, 225 USPQ 645 (Fed. Cir. 1985); In re Van Ornum, 686 F.2d 937, 214 USPQ 761 (CCPA 1982); In re Vogel, 422 F.2d 438, 164 USPQ 619 (CCPA 1970); In re Thorington, 418 F.2d 528, 163 USPQ 644 (CCPA 1969).
A timely filed terminal disclaimer in compliance with 37 CFR 1.321(c) or 1.321(d) may be used to overcome an actual or provisional rejection based on nonstatutory double patenting provided the reference application or patent either is shown to be commonly owned with the examined application, or claims an invention made as a result of activities undertaken within the scope of a joint research agreement. See MPEP § 717.02 for applications subject to examination under the first inventor to file provisions of the AIA as explained in MPEP § 2159. See MPEP § 2146 et seq. for applications not subject to examination under the first inventor to file provisions of the AIA . A terminal disclaimer must be signed in compliance with 37 CFR 1.321(b).
The filing of a terminal disclaimer by itself is not a complete reply to a nonstatutory double patenting (NSDP) rejection. A complete reply requires that the terminal disclaimer be accompanied by a reply requesting reconsideration of the prior Office action. Even where the NSDP rejection is provisional the reply must be complete. See MPEP § 804, subsection I.B.1. For a reply to a non-final Office action, see 37 CFR 1.111(a). For a reply to final Office action, see 37 CFR 1.113(c). A request for reconsideration while not provided for in 37 CFR 1.113(c) may be filed after final for consideration. See MPEP §§ 706.07(e) and 714.13.
The USPTO Internet website contains terminal disclaimer forms which may be used. Please visit www.uspto.gov/patent/patents-forms. The actual filing date of the application in which the form is filed determines what form (e.g., PTO/SB/25, PTO/SB/26, PTO/AIA /25, or PTO/AIA /26) should be used. A web-based eTerminal Disclaimer may be filled out completely online using web-screens. An eTerminal Disclaimer that meets all requirements is auto-processed and approved immediately upon submission. For more information about eTerminal Disclaimers, refer to www.uspto.gov/patents/apply/applying-online/eterminal-disclaimer.
Claims 33-34 and 36-52 are rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1-2, 4, 10, 12-14 and 16-20 of U.S. Patent No. 11,717,480 in view of Jong et al., (J. of Extracellular Vesicles; 2017, (6)) and Wels et al., (US 20170129967; published 5/11/2017).
US ‘480 claims a composition comprising sulfhydryl blocking reagent induced extracellular vesicles derived from a mammalian cell that are loaded with a medicament, wherein the EVs are free of a nuclear component and have an average diameter of between 10 nm and 10000 nm, and wherein the sulfhydryl blocking reagent induced EVs have a PDI of less than 0.5 (claim 1); wherein the mammalian cell is selected from a cell derived from a cell line (claim 2); whereby the medicament is a therapeutic agent (claim 4); wherein the EVs have an average diameter of 10 nm to 200 nm (claim 10); wherein the composition is formulated for local delivery or systemic delivery (claim 12), for intravenous delivery (claim 13), wherein the therapeutic agent is an anti-cancer agent (claim 14); wherein the composition is formulated for delivery of the compound to a human patient (claim 16), wherein the mammalian cell is a primary cell from the human patient (claim 17). US ‘480 also claims a method to treat a subject in need thereof comprising administering the composition of claim 1 to the subject (claim 18); wherein the composition is administered at the site of the tumor (claim 19); and wherein administration results in activation of T cells or stimulation of an immune response (claim 20).
Jong et al. teaches that EVs may be derived from NK cells and compositions of NK EVs are cytotoxic to cancer cells, as described above.
Wels et al. teaches the generation of NK cells that express a CAR, whereby the CAR provides a cell surface protein that may target the NK cells to HER2 expressing tumors, as described above.
It would have been obvious to one of skill in the art to utilize the CAR-expressing NK cells of Jong and Wels to derive the EVs of the composition and methods of US ‘480. One would have been motivated to do so given that NK EVs maintain cytotoxic activity against cancer cells as taught by Jong et al., and that the ErbB2 CAR, expressed as a therapeutic cell membrane protein, would target the NK EVs to HER2 expressing cancer cells, as taught by Wels et al. There would have been a reasonable expectation for success given that NK cells are mammalian cells, and a cell derived from a cell line, which are suitable cells from which to derive induced EVs, as taught by US ‘480. Thus the combination of US ‘480, Jong and Wels makes obvious the invention of the instant claims.
Specifically, the composition of US ‘480, over Jong and Wels, of claims 1-2, 4, 10, 12-14 and 16-17, for use in the method of US ‘480 claims 18-20, make obvious the method of instant claims 33-34 and 36-52; with each limitation made obvious as described in the teachings of Jong and Wels above.
Claims 33-34 and 36-52 are rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1-2, 10-11, 44 and 50 of US Patent 12,296,023 in view of Jong et al., (J. of Extracellular Vesicles; 2017, (6)) and Wels et al., (US 20170129967; published 5/11/2017) and Selaru et al., (US 2018/0028687; published 2/1/2018).
Application 17/268,952 has since issued as US Patent 12,296,023 (issued 5/13/2025). This is not a new grounds of rejection. The previous rejection over application ‘952 is maintained and updated to include the reference number of Patent ‘023, in order to reflect that after the previous office action was mailed on 2/27/2025, the ‘952 application issued as Patent ‘023. Further, as application ‘952 is now US Patent 12,296,023; the rejection has been amended to no longer be provisional.
Patent ‘023 claims a method of producing induced cell vesicles (ICVs) comprising contacting the cells with a cell blebbing buffer which comprises a sulfhydryl blocking agent (claim 1); wherein the cells are obtained from a subject that has a disorder or disease that is to be treated with the ICVs (claim 2); wherein the cell vesicles comprise viruses, viral particles or viral vectors by being produced from cells comprising the same (claim 4); wherein the viral vectors are lentiviruses (claim 5); wherein the ICVs are isolated and have an average diameter of 10 nm to 10000 nm (claim 15); wherein the cells comprise or have been modified to comprise one or more functional moieties on the cell surface (claim 18).
Jong et al. teaches that EVs may be derived from NK cells and compositions of NK EVs are cytotoxic to cancer cells, as described above.
Wels et al. teaches the generation of NK cells that express a CAR, whereby the CAR provides a cell surface protein that may target the NK cells to HER2 expressing tumors, as described above.
It would have been obvious to one of skill in the art to utilize the CAR-expressing NK cells of Jong and Wels in the method to produce ICVs/EVs of US ‘023. One would have been motivated to do so given that NK EVs maintain cytotoxic activity against cancer cells as taught by Jong et al., and that the ErbB2 CAR, expressed as a therapeutic cell membrane protein, would target the NK EVs to HER2 expressing cancer cells, as taught by Wels et al. There would have been a reasonable expectation for success given that NK cells naturally generate EVs as taught by Jong et al., and that contacting cells with a cell blebbing buffer which comprises a sulfhydryl blocking agent induces ICVs/EVs, as taught by US ‘023. Thus the combination of US ‘023, Jong and Wels makes obvious the composition comprising induced NK EVs of the instant claims; however, it does not teach a method of treating cancer comprising administering the composition of NK EVs.
Selaru et al. teaches the administration of compositions of EVs as methods for the treatment of cancer, as described above.
It would have been obvious to one of skill in the art to administer the composition of induced NK EVs of US ‘023, Jong and Wels in a method for treating a subject with cancer. One would have been motivated to do so in order to provide a therapeutic and treat a disease. There would have been a reasonable expectation for success given that the induced NK EVs of US ‘023, Jong and Wels maintain cytotoxic activity against cancer cells as taught by Jong et al., and that the ErbB2 CAR, expressed as an EV membrane protein, would target the NK EVs to HER2 expressing cancer cells, as taught by Wels et al.