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 .
Claims 3, 6-17, 19-23, 26-35, 44-50, 52-53, 57, 59, and 61-65 are cancelled.
Claims 1-2, 4-5, 18, 24-25, 36-43, 51, 54-56, 58, 60, and 66-71 are pending.
Applicant’s election without traverse of the following species: (1) the method of claim 1 and its dependent claims; (2) IFNgamma (IFNg) as the single cytokine (as recited in claim 25); (3) immobilization on the bottom surface of a vessel (as recited in claim 41); and (4) a therapeutic cell composition comprising CD4+ T cells and CD8+ T cells (as recited in claim 55).
in the reply filed on 05/26/2026 is acknowledged.
Claim 42 is withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected species, there being no allowable generic or linking claim. Election was made without traverse in the reply filed on 05/26/2026.
Claims 1-2, 4-5, 18, 24-25, 36-41, 43, 51, 54-56, 58, 60, and 66-71 are under examination on the merits.
Priority
This application is a 371 of PCT/US2022/021225, filed 03/21/2022 and claims benefit of US Provisional Application No. 63/164,527, filed 03/22/2021.
IDS
The information disclosure statements (IDS’) filed 05/13/2024 and 05/26/2026 have been considered.
Specification
The disclosure is objected to because of the following informalities: “oinclude” should read “include” at paragraph 0040 of page 12.
Appropriate correction is required.
Claim Rejections - 35 USC § 112
35 USC § 112(a)
The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
The following is a quotation of the first paragraph of pre-AIA 35 U.S.C. 112:
The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention.
Claims 1-2, 4-5, 18, 24-25, 36-41, 43, 51, 54-56, 58, 60, and 66-71 are rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the written description requirement. The claim(s) contains subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for applications subject to pre-AIA 35 U.S.C. 112, the inventor(s), at the time the application was filed, had possession of the claimed invention.
The purpose of the written description requirement is to ensure that the inventor had possession, at the time the invention was made, of the specific subject matter claimed. To satisfy the written description requirement, a patent specification must describe the claimed invention in sufficient detail that one skilled in the art can reasonably conclude that the inventor had possession of the claimed invention. See, e.g., Moba, B. V. v. Dianwnd Automation, Inc., 325 F.3d 1306, 1319, 66 USPQ2d 1429, 1438 (Fed. Cir. 2003); Vas-Cath, Inc. v. Mahurkar, 935 F.2d at 1563, 19 USPQ2d at 1116.
The Application claims broad genus of recombinant receptors.
The Application discloses that autologous primary CD4+ and CD8+T cells engineered to have a recombinant chimeric antigen receptor (CAR) containing a scFv where IFNgamma (IFNg) was the measured activity (see for example, the Examples section at page 247-248 and figure 1 of the instant disclosure). CARs are further disclosed at paragraph 0549 at pages 198-199, paragraph 0570-0573 At pages 206-208). Certain specific CD19, CD22/CD22-Fc, BCMA/BCMA-Fc, and ROR1/ROR1-Fc epitopes (compounds potentially serving as the recombinant receptor stimulating agent(s)) are disclosed (see pages 40-45, the sequence table spanning pages 250-257). Antigens encompassed by the recombinant receptor stimulating agent are more broadly enumerated at exemplary pages 199-201. Two specific scFvs (FMC63 and SJ25C1) are discussed at paragraphs 0565-0568 at pages 205-206. Certain APCs/other cells that may be used as recombinant receptor stimulating agent(s) are mentioned by name at paragraphs 0141-0147 at pages 56-60. Anti-idiotypic antibodies are briefly discussed at paragraph 0111 at page 46. Activities to be measured are discussed at exemplary paragraphs 0176-0179 at pages 71-73. There is no disclosure of which of the particular CARS/TCRS/scFvs function in the assay method as claimed (no described paratope compatible for the claimed assay method). There is no specific description of the recombinant receptor stimulating agent (epitope) that functions in the assay method as claimed (relevant for comparison of the instant fact pattern to Amgen v. Sanofi, 872 F.3d 1367 (Fed. Cir. 2017) where there was at least disclosure of the portion of the epitope bound by the antibodies)/fragment(s) thereof corresponding to the required function/response of activation/inhibition).
Therefore, in view of this disclosure, Applicant is claiming a broad genus of recombinant receptors without a representative number of species of said genus (the genus of receptors is notably not limited to any particular class (e.g: TCR, CAR, etc.), specific for any particular antigen, or required to have any particular sequence/structure accounting for binding so as to function in the assay method claimed). The specification does not provide adequate written description for the entire claimed genus of recombinant receptors because in the absence of empirical determination, one skilled in the art would be unable to immediately envision, recognize, or distinguish at least most of the members comprised within the genus claimed, specifically, which members of said genus would function with a reasonable expectation of success/reliability in the claimed assay method(s).
Regarding the unpredictability of antibodies/binding fragments thereof/scFvs, while the prior art teaches some understanding of the structural basis of antigen-antibody recognition, it is noted that the art is characterized by a high level of unpredictability, since the skilled artisan still cannot accurately and reliably predict the consequences of amino acid substitutions, insertions, and deletions in the antigen-binding domains. For example, Al Qaraghuli et al. (2020, Nature Scientific Reports 10:13969), state that the six CDRs form a continuous surface to form the paratope that binds the epitope of the cognate antigen. This suggests that a change in the CDR sequence may result in a conformationally different paratope which may fail to bind target as claimed. Here, a mutation in the CDRs may result in a paratope unable to bind any one of the recited receptor stimulating agents (targets/antigens) and/or an alteration in the function effected by binding of the receptor and the receptor stimulating agent rendering the receptor/receptor stimulating agent incompatible with the claimed assay method(s). Rabia et al (2018, Biochemical Engineering Journal 137:365-374) teach what effects mutations can have on an antibody's stability, solubility, binding affinity and binding specificity. Rabia et al report that an increase in antibody affinity can be associated with a decrease in stability (p. 366, col. 2 last paragraph; Fig. 2). Tiller et al (2017, J. Biol. Chem. (2017) 292(40) 16638–16652) and Tsuji et al (2022, J Virol 96:e00071-22) teach that mutations in the CDRs (especially HCDR3 are unpredictable and accompanied by tradeoffs in performance (for example increased affinity may lead to decreased specificity); see references in their entirety paying particular attention to the abstract of Tiller et al and the abstract and results section of Tsuji et al). The above cited references underscore the unpredictability of even a single mutation in the CDRs. The instant claims allow for mutations in the CDRs whereupon the mutated paratope may fail to bind any one of the disclosed or encompassed receptors and/or stimulating agents, as claimed. Thus, the claims need to specify exact CDR sequences of the recited CAR/TCR (scFv) receptors and of the antibody/binding portion thereof of the receptor stimulating agent(s).
Accordingly, absent empirical determination, one skilled in the art would be unable to predict or envision which CDR sequences comprised within the genus comprising the claimed CDR sequences may be used/combined/mutated such that the resultant antibody possesses an antigen-binding site capable functioning as claimed for the recited assay method(s). The general knowledge and level of skill in the art does not adequately supplement the omitted description, because specific, not general guidance is needed. Since the disclosure fails to describe relevant, identifying structural characteristics, in the form of fixed heavy and light chain CDR amino acid sequence combinations, that correlate with the ability to function as claimed, and because the one disclosed species detailed above is not sufficient to describe the claimed genus, it is submitted that the written description requirement of 35 U.S.C. 112(a) has not been met.
The written description requirement for a claimed genus may be satisfied through sufficient description of a representative number of species by actual reduction to practice, reduction to drawings, or by disclosure of relevant, identifying characteristics, i.e., structure or other physical and/or chemical properties, by functional characteristics coupled with a known or disclosed correlation between function and structure, or by a combination of such identifying characteristics, sufficient to show the applicant was in possession of the claimed genus. See Eli Lilly, 119 F.3d at 1568, 43 USPQ2d at 1406. A “representative number of species” means that the species which are adequately described are representative of the entire genus. Thus, when there is substantial variation within the genus, one must describe a sufficient variety of species to reflect the variation within the genus.
Furthermore, Applicant has not disclosed relevant, identifying characteristics of CDR region amino acid sequences that confer upon an antibody the ability to function as claimed because the instant specification does not provide structural antibody features that correlate with a functional ability to function.
Absent a clear description of the at least minimal structural features correlating with a functional ability to function as claimed which are shared by members of a genus commonly sharing this function, it is submitted that the skilled artisan could not immediately envision, recognize, or distinguish which heavy and light chain CDR amino acid sequences may be mutated/varied/interchanged such that the resultant heavy and light chain variable regions comprise six CDRs that confer the ability to function as claimed.
Applicant is directed to MPEP § 2163 for guidelines on compliance with the written description requirement. Here, applicant has not described a reasonable number of members of the genus of antibodies that would function in the method(s) as claimed, but rather has presented the public with an idea of how to perform an assay that might identify some peptides that fall within the scope of the claim. Of course, depending on what agents are used in the screening assay, it may well identify none. The Court of Appeals for the Federal Circuit addressed claims of this sort in great detail in University of Rochester v. G.D. Searle and Co. (69 USPQ 2nd 1886, CAFC 2004). In Rochester, the Federal Circuit upheld the district court's ruling that patent claims which recited administration of compounds not disclosed, but rather to be identified in a screening assay, were invalid on their face.
In Ariad, the court further noted that the written description plays a particularly important role in the biological arts, where patentees might otherwise be tempted to claim a genus of compounds by its function or result:
“The written description requirement also ensures that when a patent claims a genus by its function or result, the specification recites sufficient materials to accomplish that function—a problem that is particularly acute in the biological arts. 5 See Guidelines for Examination of Patent Applications Under the 35 U.S.C. 112, 1, “Written Description” Requirement, 66 Fed. Reg. 1099, 1105-1106 (Jan. 5, 2001). This situation arose not only in Eli Lilly but again in University of Rochester v. G.D. Searle & Co., Inc., 358 F.3d 916 [69 USPQ2d 1886] (Fed. Cir. 2004). In Rochester, we held invalid claims directed to a method of selectively inhibiting the COX-2 enzyme by administering a non-steroidal compound that selectively inhibits the COX-2 enzyme. Id. at 918. We reasoned that because the specification did not describe any specific compound capable of performing the claimed method and the skilled artisan would not be able to identify any such compound based on the specification's function description, the specification did not provide an adequate written description of the claimed invention. Id. at 927-28. Such claims merely recite a description of the problem to be solved while claiming all solutions to it and, as in Eli Lilly and Ariad's claims, cover any compound later actually invented and determined to fall within the claim's functional boundaries—leaving it to the pharmaceutical industry to complete an unfinished invention.”
Ariad Pharmaceuticals., Inc. v. Eli Lilly & Co., 94 USPQ2d 1161, 1173 (Fed. Cir. 2010) (en banc). Emphasis added.
The Federal Circuit has clarified Written Description as it applies to antibodies in the recent decision Amgen v. Sanofi, 872 F.3d 1367 (Fed. Cir. 2017). The Federal Circuit explained in Amgen that when an antibody is claimed, 35 U.S.C. 112(a) (or pre-AIA first paragraph) requires adequate written description of the antibody itself. Amgen, 872 F.3d at 1378-79. The Amgen court expressly stated that the so-called “newly characterized antigen” test, which had been based on an example in USPTO-issued training materials and was noted in dicta in several earlier Federal Circuit decisions, should not be used in determining whether there is adequate written description under 35 U.S.C. 112(a) for a claim drawn to an antibody. Citing its decision in Ariad Pharmaceuticals, Inc. v. Eli Lilly & Co., the court also stressed that the “newly characterized antigen” test could not stand because it contradicted the quid pro quo of the patent system whereby one must describe an invention in order to obtain a patent. Amgen, 872 F.3d at 1378-79, quoting Ariad, 598 F.3d 1336, 1345 (Fed. Cir. 2010). In view of the Amgen decision, adequate written description of an antigen alone is not considered adequate written description of a claimed antibody to that antigen, even when preparation of such an antibody is routine and conventional. Id.
While generically the structure of antibodies is known, the structure of the presently recited antibodies can vary substantially within the above given claimed recitations. As noted in Amgen, knowledge that an antibody binds to a particular epitope on an antigen tells one nothing at all about the structure of the antibody, wherein “instead of analogizing the antibody-antigen relationship to a ‘key in a lock,’ it [is] more apt to analogize it to a lock and ‘a ring with a million keys on it.” (Internal citations omitted). The relevant antibody art confirms this quandary, indicating that “knowledge of an epitope or antigen used to generate a monoclonal antibody is insufficient for making the original antibody available, even if suitable in vitro test systems for screening are used.” See p. 8, lines 3-5 of WO 2009/033743 A1. Therefore, those of skill in the art would not accept that the inventor had been in possession of the full genus of antibodies in the present claims.
Although screening techniques can be used to isolate CDR variant antibodies that possess the ability to function as claimed, Applicant is reminded that the written description requirement of 35 U.S.C. 112 is severable from the enablement provision. As stated in Vas-Cath Inc. v. Mahurkar (CA FC) 19 USPQ2d 1111, 935 F2d 1555, “The purpose of the 'written description' requirement is broader than to merely explain how to 'make and use'; the applicant must also convey with reasonable clarity to those skilled in the art that, as of the filing date sought, he or she was in possession of the invention. The invention is, for purposes of the 'written description' inquiry, whatever is now claimed.”
The claims further recite a broad genus of recombinant receptor stimulating agents. The specification provides that this agent may be the extracellular binding portion of an antigen, an anti-idiotypic antibody specific for the recombinant receptor’s extracellular binding domain, an antigen-presenting cell (APC), or a tumor cell in non-limiting embodiments (see for example, paragraphs 0017 and 0019 at pages 5-6 of the specification). There is no conserved structure which allows the artisan to clearly envisage which members encompassed within the genus of stimulating agents would function to stimulate a (let alone which particular) recombinant receptor in the recited method(s). The genus of stimulating agents encompasses several divergent biological classes (APCs, tumor cells, proteins, and antibodies). As discussed above, antibodies are highly unpredictable, where even a single mutation in the CDRs can dramatically impact or abrogate binding function to target. Here, the anti-idiotypic antibody must not only bind to the receptor, but must result in stimulation. Proteins are similarly unpredictable and intolerant or mutation/engineering. Regarding the state of the art, Listov et al (Opportunities and challenges in design and optimization of protein function. Nat Rev Mol Cell Biol 25, 639–653 (2024)) teach that the primary amino acid sequence determines downstream structure (protein folding), which then determines function (presenting both the inverse folding problem and the inverse function problem (see for example Figure 1 and its caption; see also Mishra et al (Inaccurate secondary structure predictions often indicate protein fold switching. Protein Sci. 2019 Aug;28(8):1487-1493. doi: 10.1002/pro.3664. Epub 2019 Jun 17)). Expanding on these problems in proteomics, Reardon (Nature 635, 246-248 (2024)) explains that the goal of designing a protein with known and predictable function, binding partners, size, location, and other traits is, for the moment, a dream. Reardon teaches that further challenges in protein design include predicting how a protein, even if it binds to target, will function upon said binding. Reardon teaches that the primary structure (amino acid sequence) of a protein is critical to function, noting that even proteins of similar shape do not execute the same functions, while those with different shapes may carry out the same tasks. Reardon goes on to teach that it is not always apparent which parts of the primary sequence are important; a seemingly useless amino-acid chain on the side of an enzyme, for instance, might affect how tightly a protein can bind to other molecules or its ability to flip between conformational states. Moreover, Reardon explains that when researchers attempt to solve the structure of a protein experimentally, they often end up seeing only the most stable conformation, which is not necessarily the form the protein takes when it is active (see for example, pages, 246-247 of Reardon). Antibodies and proteins, being the two classes with the most description in the specification are discussed as exemplary. However, the use of any epitope in an assay carries a degree of art-acknowledge unpredictability; the prior art supports that epitope selection is a critical step in immunoassay design and that said selection is unpredictable. Proteintech (The importance of epitope selection in experimental design, Proteintech, obtained from: https://www.ptglab.com/news/blog/the-importance-of-epitope-selection-in-experimental-design/?srsltid=AfmBOophB0oOURPWVt8-Ev696rJUsE1_yPXsMEFvA57ECk6diMWAmt6D; accessed 02/10/2026) teaches that, when designing an experiment that uses antibodies, one often overlooked parameter is the exact binding site of your antibody on the protein of interest, also known as the epitope. An antibody' s primary role is to bind to a specific protein (also known as the antigen or immunogen) which in turn allows for the detection, neutralization, or modification of the protein' s activity. Carefully choosing your antibodies based on epitope binding site can greatly influence experimental outcomes, therapeutic strategies, and diagnostic accuracy (see for example, paragraph 1 of page 1-13). Additionally, Proteintech teaches that an epitope which functions in one assay method may fail in another) see for example, pages 1/13-2/13).
Therefore, the genera of recombinant receptors and recombinant receptor stimulating agents, as claimed are only disclosed by function/insufficient structure, without a representative number of species or unifying, conserved structure clearly enabling one skilled in the art to readily envisage the members of the genus claimed which would function as claimed in the claimed method(s). The claims as drafted reach far beyond what is disclosed, let alone what is adequately described attempting to receptors which have yet to be invented. In Fiddes, claims directed to mammalian FGF' s were found to be unpatentable due to lack of written description for that broad class. Further, "One cannot describe what one has not conceived. See Fiddes v. Baird, 30 USPQ2d 1481 at 1483. In Fiddes, claims directed to mammalian FGF's were found to be unpatentable due to lack of written description for that broad class. Therefore, claims 1-2, 4-5, 18, 24-25, 36-41, 43, 51, 54-56, 58, 60, and 66-71 are deemed to fail to meet the written description requirement, as presently drafted.
Applicant is deemed to have provided sufficient written description of the receptor stimulating agents and scFvs (having 6 fully disclosed CDRs) set forth in the table on pages 250-257, where the fully sequence (100% identity) is required. Through the patent literature incorporated by reference, Applicant is deemed to have demonstrated that the state of the prior art provides written description of CARs that bind BCMA (see exemplary paragraphs 0570-0571 at pages 206-207), scFvs/CARs that bind GPRC5D (see exemplary paragraph 0572 at page 207), CARs for a universal tag/epitope (see exemplary paragraph 0573 at page 207). The state of the prior art provides description of CARs targeting CD19 and BCMA (see for example, Xi et al (J Vis Exp. 2019 Nov 12;(153). doi: 10.3791/5903) at paragraph 1 of the Introduction at page 1). Receptor stimulating agents which are adequately described so as to meet the written description requirement are:
Human BCMA and/or a sequence with 100% identity to SEQ ID NO: 18 or SEQ ID NO: 13 (see for example, paragraph 0093 at page 40 of the specification and paragraph 0105 at page 44 of the specification);
A sequence having 100% identity to SEQ ID NO: 16 or SEQ ID NO: 17 (see paragraphs 0098-0102 at pages 42-43 of the specification);
Human CD22 and/or a sequence with 100% identity to SEQ ID NO: 14 or SEQ ID NO: 21 (see for example, paragraph 0095 at page 41 of the specification and paragraph 0107 at page 44 of the specification);
Human ROR1 and/or a sequence with 100% identity to SEQ ID NO: 19 or SEQ ID NO: 20 (see for example, paragraph 0094 at page 40 of the specification and paragraph 0106 at page 44 of the specification);
One or more of the full, non-mutated antigens of paragraph 0090 at pages 38-39;
CD19 and/or a sequence with 100% identity to SEQ ID NO: 15 (see for example, paragraph 0096 at page 41); and
CD33 and /or a sequence with 100% identity to SEQ ID NO: 12 (see for example, paragraph 0109 at page 45).
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
Claim(s) 1, 4-5, 18, 24-25, 36-37, 40-41, 43, 56, 58, 66, and 71 is/are rejected under 35 U.S.C. 103 as being unpatentable over Xi et al (J Vis Exp. 2019 Nov 12;(153). doi: 10.3791/5903) in view of Goedhart (Data manipulation? It’s normal(izaion)!, The Node, obtained from: https://thenode.biologists.com/data-normalization/research/ (posted 2019)).
Regarding claim 1, Xi et al teach a quantitative real-time in vitro cytolysis assay system to evaluate the potency of chimeric antigen receptor (CAR) T cells targeting liquid and solid tumor cells. The in vitro potency of these CAR T cells is then evaluated in real-time using the highly sensitive impedance-based xCELLigence assay. CAR T-cells against BCMA, CD-19, CD20, and CD22 are known in the art for treating cancer such as hematologic malignancies (where the CAR T cell may be autologous or allogenic). Xi et al teach that there is a critical need for the development of solid tumor-specific CAR T cells which can overcome these barriers to efficacy and the problem of "on target-off tumor" toxicity. While a multitude of in vitro and in vivo approaches are warranted in the design and testing of CAR T cells, a robust and predictive in vitro potency assay is of primary importance. In order to assess the potency of CAR T cells, various in vitro methods have been developed, many of which measure surrogate markers such as cytokines that are released by the CAR T cells as they kill the target cells (see for example, page 1). Alternative assays, which measure byproducts of CAR T-cell interaction with target cells as an indication of potency, include the quantitation of various cytokines released by CAR T cells using either flow cytometry-based methods or enzyme-linked immunosorbent assays (see for example, the final paragraph of page 1 bridging page 2). Xi et al teach that methods of genetically engineering T cells with manufactured TCRs/CARs are known in the art and that the potency assay of Xi et al is a simple functional assay and can be advantageously used in conjunction with genetic engineering techniques to design optimal and efficacious CARs in a high-throughput fashion (see for example, page 2 and paragraph 4 of the Discussion section on page 7).
Regarding step (a): Xi et al teach that previously frozen PBMCs are activated and transfected to obtain engineered CAR T-cells (see for example steps 1-Generation of CAR-encoding Lentivirus and 2- Generation and expansion of CAR T cells under the Protocol heading at page 2). Target cells (reading on the recombinant receptor stimulating agent and ‘target’ of the titrated effector (E): target (T) ratio as instantly recited) are plated onto the wells of the E-plate. The cells may be adherent cells (which would be understood to be immobilized onto the E plate surface in the absence of a preclusive definition). Residual media is removed from the wells prior to addition of 100 µL of serially diluted effector CAR T cells (reading on the ‘effector’ of the titrated effector (E): target (T) ratio as instantly recited) or other control cells (i.e. Mock CAR T cells) to achieve the desired E:T ratios (see for example, Step 4-Real Time Cytolysis potency assay of page 3). The CAR T cells/controls in serial dilutions (reading upon a plurality of incubations where the instant disclosure does not provide a closed definition of this phrase, but describes a single incubation of multiple conditions (dilutions/CAR T cells) rather than a plurality of sequential incubations of the same set/population of cells; this is further bolstered by the subsequent wherein clause of claim 1) are allowed to sit/incubate with the target cells logically adhered to the E-plate (where if they were not adhered, the cells would have been fully removed with the removal of the media prior to addition of the CAR T cells such that no observable effect/activity of the T cells would be expected to be tested and/or measured and where, for non-adherent cells, a tethering reagent (such as an antibody specific for a surface antigen on the target cell) is used prior to plating the target cells). Xi et al teach that at key time points xCELLigence data acquisition can be paused and the plate removed in order to collect small samples to be analyzed by orthogonal assays (i.e., measuring cytokine production by ELISA or flow cytometry; where in the EGFR-GITR-CD3 CAR T-cell experiment, INFg yield was measured with an ELISA kit (following the instructions of the manufacturer) (see for example, Step 4-Real Time Cytolysis potency assay of page 3).
Regarding step B: Xi et al teach that at key time points xCELLigence data acquisition can be paused and the plate removed in order to collect small samples to be analyzed by orthogonal assays (i.e., measuring cytokine production by ELISA or flow cytometry; where in the EGFR-GITR-CD3 CAR T-cell experiment, INFg yield was measured with an ELISA kit (following the instructions of the manufacturer) (see for example, Step 4-Real Time Cytolysis potency assay of page 3).
Regarding step C: Xi et al do not teach normalization of the cytokine data.
However, Goedhart teaches that a definition of normalization would be “the rescaling of data to facilitate comparison”. While the examples explicitly discussed by Goedhart use experimental data from fluorescence spectroscopy or imaging, rescaling/normalization methods are widely applied to all sorts of data (see for example, paragraph 1 of page 1). Goedhart further teaches that normalization of values based on the maximal value is common for the rescaling of absorbance and emission spectra from spectroscopy (citing to Mastop et al, 2017 as providing further examples). The shape of a spectrum is usually the feature of interest instead of their amplitude. The normalization is done by dividing each value by the maximal value, to enable the comparison of spectral shapes (see for example, page 4).
It would have been prima facie obvious to the person of ordinary skill in the art to arrive at the claimed invention from the disclosures of the combined references before the effective filing date of the claimed invention. The artisan would have been motivated to make and use the potency assay for CAR T cells of Xi et al using IFNgamma (IFNg) release as a measure of potency because Xi et al teach that determining the potency of a CAR T cell, which is taught to be a matter of serious importance.. The artisan would have found it obvious to modify the assay of Xi et al to include normalization of the cytokine (IFNg) release data to the maximum observed value to facilitate comparison of the different conditions (the titrated ratio of cells to target represented in the plurality of incubations) as taught by Goedhart. The artisan would have had a reasonable expectation of success based on the cumulative disclosures of these prior art references prior to the effective filing date.
Regarding claim 4, as discussed above, the assay of Xi et al uses a set/constant number of cells (reading on the instantly recited constant number as supported by the text of paragraph 0076 at page 30 of the instant specification) for a plurality of incubations where the concentration of the target (receptor-stimulating agent) is varied (titrated) in different wells of the E-plate for measurement of IFNg release by ELISA, generating a plurality of titrated ratios.
Regarding claim 5, Xi et al teach that, in the assay, residual media is removed from the wells prior to addition of 100 µL of serially diluted effector CAR T cells or other control cells (i.e. Mock CAR T cells) to achieve the desired E:T ratios (see for example, Step 4-Real Time Cytolysis potency assay of page 3), where the technology underlying the assay has demonstrated reliable function across a large dynamic range (with E:T ratios from 20:1 to 1:20). Thus, the artisan would have understood that Xi et al are titrating the E: T ratios in the assay by varying the number of effector (CAR containing) cells relative to a fixed concentration of target (recombinant receptor stimulating agent). Additionally, figure 1, at step 3 specifically shows the E: T ratios of 0:1, 0.1:1, 0.2:1, and 1:1, which clearly shows a fixed concertation of target and a varied amount of effector cells to titrate the E:T ratios (see page5 at figure 1, for example).
Regarding claim 18, Xi et al teach the assay comprising 3 or more incubations (see for example, figure 1 showing 4 incubations of the cells at differing E:T ratios at page 5 and figure 4 showing 4 incubations of different conditions at page 6).
Regarding claims 24-25, as noted above, Xi et al teach measurement of IFNg as the receptor-dependent activity (a measure of CAR T cell potency).
Regarding claim 36, Xi et al teach the development and production of potent CAR T-cells targeting antigens with unique or preferential expression on solid and liquid tumor cells. xCELLigence utilizes specialized microtiter plates (E-Plates) that contain gold biosensors embedded in the bottom of each well. Working with either adherent solid tumor cells, or liquid cancer cells that have been tethered using specific antibodies, these biosensors monitor in real-time CAR T cell-induced changes in target cell (see for example, pages 1-2). The artisan would understand this disclosure to mean that the CAR T cell is targeting the target cell by binding between the CAR (recombinant receptor) and a surface expressed target antigen on the immobilized target cell (or a fragment thereof).
Regarding claim 37, the instant specification provides that an exemplary recombinant receptor stimulating agent include antigens (e.g., purified or recombinant antigens) of the recombinant receptor (see paragraph 0077 at page 31)…where in some embodiments, the antigen is or includes…CD19…(see paragraph 0090 at pages 38-39). Where there is no preclusive definition provided, the embodiment of Xi et al where the immobilized receptor stimulating agent is a target cell, said target cell being an adherent cell, such as a HeLa cell (advantageously allowing for examination of therapeutic cell potency against liquid tumor cells without the need of a tethering agent using a readily available cell source/product) genetically engineered to stably express one or more tumor antigens, such as CD19, is deemed to read upon the recitation that the receptor stimulating agent comprises a recombinant antigen (see for example, page 7) where the therapeutic cell is a CAR T-cell binding CD19, which are taught to be known in the art with certain CD19 CAR-T cells having gained FDA approval for treating various cancers (with the understanding that a chimeric antigen receptor is by nature a recombinant receptor) (see for example, page 1).
It would have been prima facie obvious to the person of ordinary skill in the art to arrive at the claimed invention from the disclosures of the combined references before the effective filing date of the claimed invention. The artisan would have been motivated to make and use the potency assay for CAR T cells of Xi et al in view of Goedhart in order to determine the potency of a CAR T cell for non-adherent cells such as certain tumor cells, using a readily available cell source that obviates the need for a tethering agent, thus simplifying the assay. The particular antigen utilized is a matter of routine optimization for the artisan to select an antigen that the therapeutic cell recognizes/binds to determine the potency pf the therapeutic cell composition against a desired target in an optimally streamlined assay (see MPEP § 2144.05). The artisan would have had a reasonable expectation of success based on the cumulative disclosures of these prior art references prior to the effective filing date.
Regarding claims 40-41, as noted above, Xi et al teach that the receptor-stimulating agent is immobilized to the wellplate (E plate) either by expression of the agent on an adherent cell (reading upon immobilization in the absence of a preclusive definition) of via a tethering agent. The surface of the E plate/wellplate upon which the receptor-stimulating agent is immobilized reads upon the recited surface of the vessel which the plurality of incubations are performed because the incubations occur in the wells, wherein the agent is immobilized.
Regarding claim 43, as discussed above, Xi et al teach a CAR T cell potency assay wherein the target (recombinant receptor-stimulating agent) is expressed on the surface of a cell (said cell reading upon an antigen-expressing cell).
Regarding claim 56, as discussed above, the assay of Xi et al uses T cells wherein the recombinant receptor is a CAR.
Regarding claim 58, as discussed above, the assay of Xi et al uses an e-plate having multiple wells wherein the plurality of incubations occur, said E-plate reading upon the recitation of a multi-well plate.
Regarding claim 66, as discussed above, Xi et al teach that at key time points xCELLigence data acquisition can be paused and the plate removed in order to collect small samples to be analyzed by orthogonal assays (i.e., measuring cytokine production by ELISA or flow cytometry; where in the EGFR-GITR-CD3 CAR T-cell experiment, INFg yield was measured with an ELISA kit (following the instructions of the manufacturer) (see for example, Step 4-Real Time Cytolysis potency assay of page 3).
Regarding claim 71, Xi et al teach comparison of CD22-CAR T cells to negative controls (untransduced T cells and Mock CAR T cells) (see for example, paragraph 2 of page 4). The mock CAR T cell control is deemed to be an embodiment encompassed by the therapeutic cell compositions (having a recombinant receptor such as a CAR) as instantly recited. The artisan would have found it obvious to modify the assay of the combined prior art to include a plurality of incubations for two or more therapeutic cell compositions in order to compare a test composition to one or more controls or to compare multiple test compositions to select for the cell with optimal activation/stimulation in response to the stimulating agent (as measured by IFNg release).
Claim(s) 2 and 67 is/are rejected under 35 U.S.C. 103 as being unpatentable over Xi et al and Goedhart, as applied to claims 1, 4-5, 18, 24-25, 36-37, 40-41, 43, 56, 58, 66, and 71, in further view of Carney (Relative Potency, BMG LabTech, obtained from: https://www.bmglabtech.com/en/blog/relative-potency/ (posted/pub 2019)).
Regarding claim 2, the combined references do not explicitly teach determination of a half-maximal receptor-dependent activity (IFNg release).
However, Carney teaches that the concentration at which 50% of the response is observed, is known as the EC or IC value (see for example, page 1). Carney further teaches that to quantify relative potency, the substances being compared are typically assayed across a range of concentrations at which the effect of the compound is quantified (a dose-response assay). There are a wide range of assays that allow the quantification of the effect of a compound, and the most appropriate option often depends of the characteristics and action of the compound itself. This measurement can include quantifying the extent of binding of a ligand to a receptor, the downstream intra-cellular response, or a change in the level of gene expression. Microplate readers such as those from BMG LABTECH provide a flexible platform on which to achieve high throughput measurement of many of these assay techniques. the concentration at which 50% of the response is observed can be determined. This is known as the EC50 or IC50 value, and can be used to compare the effectiveness of a compound. Many software packages, including the MARS data analysis software included with BMG LABTECH microplate readers, are capable of fitting curves to data and providing an EC50 value.
It would have been prima facie obvious to the person of ordinary skill in the art to arrive at the claimed invention from the disclosures of the combined references before the effective filing date of the claimed invention. The artisan would have been motivated to make and use the potency assay of Xi and Goedhart et al as modified by Carney to determine the EC50 (half-maximal receptor-dependent activity) because Carney teaches this value can be used to compare the effectiveness of a compound, such as a therapeutic CAR T cell composition of Xi et al and Goedhart. The artisan would have had a reasonable expectation of success based on the cumulative disclosures of these prior art references prior to the effective filing date.
Regarding claim 67, the specification states that exemplary reference standards may be a different therapeutic cell composition (paragraph 0202 at page 80 of the instant specification). Xi et al teach comparison of CD22-CAR T cells to negative controls (untransduced T cells and Mock CAR T cells) (see for example, paragraph 2 of page 4). The negative control Mock CAR T cells (being an encompassed embodiment of a different therapeutic cell composition which is an encompassed embodiment of a reference standard) of Xi et al are deemed to read upon the recited ‘reference standard’ and the measurement of IFNg release from said Mock CAR T cells reads upon the receptor-dependent activity of the reference standard. Note that Xi et al teach that IFNg may be measured by ELISA as a surrogate for T cell activation as part of the potency assay (where a T cell must be activated prior to exerting a therapeutic effect).
It would have been prima facie obvious to the person of ordinary skill in the art to arrive at the claimed invention from the disclosures of the combined references before the effective filing date of the claimed invention. The artisan would have been motivated to make and use the potency assay of Xi and Goedhart et al as modified by Carney to determine the relative potency (as a measure of IFNg release using ELISA corresponding to the therapeutic cell composition (such as the CD22-CAR T cell of Xi et as compared to the measurement of IFNg release using ELISA corresponding to the negative control Mock CAR T cells taught by Xi et al) in order to determine that the effect of the test condition (the therapeutic cell compositing) is a true observed effect. The artisan would have had a reasonable expectation of success based on the cumulative disclosures of these prior art references prior to the effective filing date.
Claim(s) 38-39 is/are rejected under 35 U.S.C. 103 as being unpatentable over Xi et al and Goedhart, as applied to claims 1, 4-5, 18, 24-25, 36-37, 40-41, 43, 56, 58, 66, and 71, in further view of Hauskins et al (WO2018023100 A2; as cited on the 05/13/2024 IDS).
Regarding claims 38-39, the combined references do not teach that the antigen is an anti-idiotypic antibody.
However, Hauskins et al teach anti-idiotype antibodies that specifically recognize anti-CD19 antibody moieties, in particular, anti-CD19 antibody moieties present in recombinant receptors, including chimeric antigen receptors (CARs). The disclosure further relates to uses of anti-idiotype antibodies for specifically identifying and/or selecting cells expressing such recombinant receptors, such as anti-CD19 CAR T cells. The disclosure further relates to uses of anti-idiotype antibodies for specifically activating such cells (see for example, the abstract). Hauskins et al further teach that, as shown in FIG. 10A, intracellular cytokine levels of TNFa, IFNg and IL2 cytokines were induced in CAR+ T cells (EGFRt+), but not in CAR- T cells (EGFR ), when the cells were cultured in the presence of the anti-ID B-1 conjugated beads. In this study, the extent of stimulation observed in the presence of anti-ID conjugated beads was similar to stimulation of CAR+ T cells using antigen-expressing K562-CD19 cells, which is an alternative CAR-specific stimulation reagent (FIG. 10B). These results demonstrated that anti-ID conjugated to beads are agonistic and specifically stimulate T cells expressing a CAR having an antigen-binding domain recognized by the anti-ID antibody. Further, the immobilized anti-idiotypic antibody reagent provides for a better CAR-specific stimulation reagent compared to cell lines, which require cell culture and are prone to lot to lot variability (see for example, paragraph 0587 and paragraph 0054 at pages and 14, respectively) where the anti-ID antibody may be immobilized to a solid support (see for example, paragraph 0060 at page 16).
It would have been prima facie obvious to the person of ordinary skill in the art to arrive at the claimed invention from the disclosures of the combined references before the effective filing date of the claimed invention. The artisan would have been motivated to make and use the potency assay of Xi and Goedhart et al as modified by Hauskins et al to use and anti-idiotypic antibody as the immobilized receptor-stimulating agent because Hauskins et al teach that this anti-ID antibody provides for a better CAR-specific stimulation reagent compared to cell lines (prone to variability/quality control issues) where the activation of the T-cell, as measured by IFNg release by the CAR T-cells, where the activation potential of the cell would have been reasonably understood to represent a marker of potency of the therapeutic cell composition CAR T-cell). The artisan would have had a reasonable expectation of success based on the cumulative disclosures of these prior art references prior to the effective filing date.
Claim(s) 51 and 54-55 is/are rejected under 35 U.S.C. 103 as being unpatentable over Xi et al and Goedhart, as applied to claims 1, 4-5, 18, 24-25, 36-37, 40-41, 43, 56, 58, 66, and 71, in further view of Kleiveland et al (Peripheral Blood Mononuclear Cells. In: Verhoeckx K, Cotter P, López-Expósito I, et al., editors. The Impact of Food Bioactives on Health: in vitro and ex vivo models [Internet]. Cham (CH): Springer; 2015. Chapter 15. Available from: https://www.ncbi.nlm.nih.gov/books/NBK500157/ doi: 10.1007/978-3-319-16104-4_15).
Regarding claims 51 and 54-55, Xi et al teaches that the therapeutic cell composition begins with PBMCs, whereupon, after incubation with CAR T cell medium, transduction enhancement agent, and lentivirus, the cells are gated to arrive at viable/live CD3+ T cells (see for example, pages 2-3). Primary cells, absent a clear and closed definition, are understood to invoke the common parlance meaning of cells derived from living tissue, which, PBMCs being derived from peripheral blood, would mean that PBMCs are understood to comprise primary cells, even after the transfection and gating steps of Xi et al. Xi et al do not explicitly teach that the Cd3+ T cells are CD4+ and/or CD8+. However, the artisan would understand the composition resulting from the steps of Xi et al to comprise CD4+ and CD8+ T cells because Kleiveland et al evidence teachings that human peripheral blood mononuclear cells (PBMCs) are isolated from peripheral blood (understood to be primary cells) and include lymphocytes, the lymphocyte population including 70–85 % CD3 + T cells, where the CD3 + lymphocytes are composed of CD4 + and CD8 + T cells, roughly in a 2:1 ratio (see for example, section 15.1 spanning pages 161-162).
It would have been prima facie obvious to the person of ordinary skill in the art to arrive at the claimed invention from the disclosures of the combined references before the effective filing date of the claimed invention. The artisan would have been motivated to make and use the potency assay of Xi and Goedhart et al for the reasons iterated in the rejection of instant claim 1, where the artisan would have understood the therapeutic cell composition resulting from the steps of the combined assay to include primary cells, CD3+ cells, CD4+ cells, and CD8+ cells in light of the evidentiary teachings of Kleiveland et al. The artisan would have had a reasonable expectation of success based on the cumulative disclosures of these prior art references prior to the effective filing date.
Claim(s) 60 and 68-69 is/are rejected under 35 U.S.C. 103 as being unpatentable over Xi et al, Goedhart, and Carney as applied to claims 2 and 67, in further view of Warren (Br J Clin Pharmacol. 2019 Oct;85(10):2187-2193. doi: 10.1111/bcp.13949. Epub 2019 May 17.).
Regarding claim 60,
The combined references do not teach dose determination based on half maximal activity.
However, Warren teaches that the half‐maximal point of the curve, the effective dose‐50%, or ED50, are synonymous (see for example, paragraph 2 of the Introduction at page 2187) such that the artisan would understand that the ED50 is synonymous with the instantly recited dose that results in a half-maximal activity. Warren further teaches that when choosing a medicine two aspects determine the balance between benefit and harm (risk–benefit), matching the medicine to the individual and the choice of dose. Warren teaches that knowing the relationship between dose and response allows a calculation of the dose that causes 50% of the maximal effect, the ED50 and that rational drug dosing depends on defining the ratio of the dose to the ED50 (dose resulting in half-maximal activity). The ED50 of each drug has two scales, whether the effect measured is for efficacy or safety (see for example, the abstract at page 2187). Warren further teaches that the ED50 can predict the likely effective tissue concentration and dose needed when the drug is given in vivo (see for example, paragraph 2 of the Introduction at page 2187).
It is noted that no steps are specified for how the dose of the cells of the composition for administration to a subject in need thereof is determined based upon the half-maximal recombinant receptor-dependent response.
It would have been prima facie obvious to the person of ordinary skill in the art to arrive at the claimed invention from the disclosures of the combined references before the effective filing date of the claimed invention. The artisan would have been motivated to determine the dose of therapeutic cell compositions to be administered to a subject in need thereof based on the EC50/ED50 value because Warren teaches that the ED50 can predict the likely effective tissue concentration and dose needed when the drug is given in vivo (see for example, paragraph 2 of the Introduction at page 2187). The artisan would have had a reasonable expectation of success based on the cumulative disclosures of these prior art references prior to the effective filing date.
Regarding claim 68, note that no definition is provided to specify what the potency of the therapeutic cell composition is relative to and that no steps are specified for how the dose of the cells of the composition for administration to a subject in need thereof is determined based upon the half-maximal recombinant receptor-dependent response.
It would have been prima facie obvious to the person of ordinary skill in the art to arrive at the claimed invention from the disclosures of the combined references before the effective filing date of the claimed invention. The artisan would have been motivated to determine the dose of therapeutic cell compositions to be administered to a subject in need thereof based on the EC50/ED50 value because Warren teaches that the ED50 can predict the likely effective tissue concentration and dose needed when the drug is given in vivo (see for example, paragraph 2 of the Introduction at page 2187). The artisan would have found it obvious to look at the potency, as indirectly indicated by activation measured by IFNg release, of a therapeutic cell composition relative to a reference standard (such as T cells from the subject which are not transfected or Mock CAR T cells) in order to verify the enhanced efficacy of the therapeutic cell composition relative to the control, using the dose/concertation resulting in a half maximal activity (EC50 of Carney/ ED50 of Warren et al) to aid in determination of a dose to be administered according to the combined teachings of the cited references. The artisan would have had a reasonable expectation of success based on the cumulative disclosures of these prior art references prior to the effective filing date.
Regarding claim 69,
Carney et al further teaches that the EC50 (concentration at which a half maximal effect is observed; synonymous with the concertation of the titrated ration which results in the half maximal activity as discussed in the rejection of claim 2 above) occurs on a linear portion of the sigmoidal curve of the dose-response data (see for example, figure 2 at page 2).
Warren et al, as discussed above, teach that rational drug dosing depends on defining the ratio of the dose to the ED50 (the dose at which a half maximal response if observed (see the rejection of claim 600 above) such that EC50 and ED50 would have been understood to be synonymous with the titrated ratio concentration/dose responsible for half-maximal activity of claim 67 from which claim 69 depends). The ED50 of each drug has two scales, whether the effect measured is for efficacy, or safety (see for example, the abstract at page 2187). Warren further teaches that The half‐maximal point of the curve, the effective dose‐50%, or ED50, can predict the likely effective tissue concentration and dose needed when the drug is given in vivo (see for example, paragraph 2 of the Introduction at page 2187).
As discussed above, it would have been prima facie obvious to determine the dose based on the ED50 where the artisan would have understood that the ED50 is determined by plotting dose (titrated concentrations of the therapeutic cell composition) against the response (measured IFNg release), the ED50 being pulled from the linear portion of the sigmoidal dose-response curve. The artisan would have had a reasonable expectation of success based on the cumulative disclosures of these prior art references prior to the effective filing date.
Claim(s) 70 is/are rejected under 35 U.S.C. 103 as being unpatentable over Xi et al, Goedhart, Carney, and Warren, as applied to claims 60 and 68-69, in further view of Little (Essentials in Bioassay Design and Relative Potency Determination, BioPharm International, Vol 29, Iss. 4, pub 04-01-2016, obtained from: https://www.biopharminternational.com/view/essentials-bioassay-design-and-relative-potency-determination).
Regarding claim 70, as the combined references do not explicitly label the components of the dose-response sigmoidal curve showing the upper and lower asymptote.
However, Little teaches the ideal dose response curve is a five-point curve for parallel line analysis (linear) and a nine-point dose scheme or more for sigmoidal fits. For a sigmoidal curve, ideally it should be three points in the inactive or low response section of the curve, three points in the linear part of the curve and three points in the saturated area of the curve on the log or log 10 scale from a serial dilution. The inactive or low response section of the curve (lower line of the sigmoid curve substantially parallel to the X-axis) being the lower asymptote and the upper response in the saturated area of the curve (upper most line of the sigmoid curve substantially parallel to the X-axis) being the upper asymptote. The lower asymptote is clearly the minimal activity (response) portion and the upper asymptote is clearly the maximal activity (response portion).
It would have been prima facie obvious to the person of ordinary skill in the art to arrive at the claimed invention from the disclosures of the combined references before the effective filing date of the claimed invention. The artisan would have been motivated to have the titrated ratio encompass a lower asymptote and an upper asymptote because Little teaches that the ideal dose-response curve has a lower (minimal) and upper (maximal) asymptote. The artisan would have had a reasonable expectation of success based on the cumulative disclosures of these prior art references prior to the effective filing date.
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.
Claim(s) 1, 4-5, 18, 24-25, 36-37, 40-41, 43, 51, 54-56, 58, 66, and 71 is/are provisionally rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1-185 of copending Application No. 19/475,856 (‘856) in view of Xi et al (J Vis Exp. 2019 Nov 12;(153). doi: 10.3791/5903) in view of Goedhart (Data manipulation? It’s normal(izaion)!, The Node, obtained from: https://thenode.biologists.com/data-normalization/research/ (posted 2019)).
The claims, while not verbatim, are directed to overlapping subject matter, namely assays to determine potency/relative potency of therapeutic cell compositions.
This is a provisional nonstatutory double patenting rejection.
Regarding claim 1, ‘856 claims a method of determining potency of an effector cell composition, the method comprising:
(a) performing a plurality of incubations, each of the plurality of incubations comprising
culturing cells of an effector cell composition with target cells expressing a cell surface target antigen and a reporter molecule stably expressed by the target cells, wherein:
the cells of the effector cell composition that are cultured comprise cells that are engineered to express a recombinant receptor that specifically binds to the target antigen and cells that do not express the recombinant receptor; and
each of the plurality of incubations is performed with a different titrated ratio of cells of the effector cell composition to the target cells, wherein each of the different titrated ratios is based on recombinant receptor-expressing cells of the effector cell composition;
(b) measuring, based on expression or activity of the reporter molecule, a cytotoxic activity from each of the plurality of incubations, wherein the expression or activity of the reporter molecule is inversely correlated with the cytotoxic activity; and
(c) determining, based on the cytotoxic activity measured for each of the plurality of incubations, a titrated ratio that results in a half-maximal cytotoxic activity of the effector cell composition,
(see ‘856 claims 1 and 3). ‘865 claims the method of its claim 1 further comprising determining a relative potency of the effector cell composition by comparing the titrated ratio resulting in the half-maximal cytotoxic activity of the effector cell composition to a titrated ratio resulting in a half-maximal cytotoxic activity of a reference standard (see ‘856 claim 2).
‘856 does not claim that the receptor-dependent activity is cytokine expression or production or the activity data from the incubations is normalized.
Regarding claim 1, Xi et al teach a quantitative real-time in vitro cytolysis assay system to evaluate the potency of chimeric antigen receptor (CAR) T cells targeting liquid and solid tumor cells. The in vitro potency of these CAR T cells is then evaluated in real-time using the highly sensitive impedance-based xCELLigence assay. CAR T-cells against BCMA, CD-19, CD20, and CD22 are known in the art for treating cancer such as hematologic malignancies (where the CAR T cell may be autologous or allogenic). Xi et al teach that there is a critical need for the development of solid tumor-specific CAR T cells which can overcome these barriers to efficacy and the problem of "on target-off tumor" toxicity. While a multitude of in vitro and in vivo approaches are warranted in the design and testing of CAR T cells, a robust and predictive in vitro potency assay is of primary importance. In order to assess the potency of CAR T cells, various in vitro methods have been developed, many of which measure surrogate markers such as cytokines that are released by the CAR T cells as they kill the target cells (see for example, page 1). Alternative assays, which measure byproducts of CAR T-cell interaction with target cells as an indication of potency, include the quantitation of various cytokines released by CAR T cells using either flow cytometry-based methods or enzyme-linked immunosorbent assays (see for example, the final paragraph of page 1 bridging page 2). Xi et al teach that methods of genetically engineering T cells with manufactured TCRs/CARs are known in the art and that the potency assay of Xi et al is a simple functional assay and can be advantageously used in conjunction with genetic engineering techniques to design optimal and efficacious CARs in a high-throughput fashion (see for example, page 2 and paragraph 4 of the Discussion section on page 7).
Regarding step (a): Xi et al teach that previously frozen PBMCs are activated and transfected to obtain engineered CAR T-cells (see for example steps 1-Generation of CAR-encoding Lentivirus and 2- Generation and expansion of CAR T cells under the Protocol heading at page 2). Target cells (reading on the recombinant receptor stimulating agent and ‘target’ of the titrated effector (E): target (T) ratio as instantly recited) are plated onto the wells of the E-plate. The cells may be adherent cells (which would be understood to be immobilized onto the E plate surface in the absence of a preclusive definition). Residual media is removed from the wells prior to addition of 100 µL of serially diluted effector CAR T cells (reading on the ‘effector’ of the titrated effector (E): target (T) ratio as instantly recited) or other control cells (i.e. Mock CAR T cells) to achieve the desired E:T ratios (see for example, Step 4-Real Time Cytolysis potency assay of page 3). The CAR T cells/controls in serial dilutions (reading upon a plurality of incubations where the instant disclosure does not provide a closed definition of this phrase, but describes a single incubation of multiple conditions (dilutions/ CAR T cells) rather than a plurality of sequential incubations of the same set/population of cells; this is further bolstered by the subsequent wherein clause of claim 1) are allowed to sit/incubate with the target cells logically adhered to the E-plate (where if they were not adhered, the cells would have been fully removed with the removal of the media prior to addition of the CAR T cells such that no observable effect/activity of the T cells would be expected to be tested and/or measured and where, for non-adherent cells, a tethering reagent (such as an antibody specific for a surface antigen on the target cell) is used prior to plating the target cells). Xi et al teach that at key time points xCELLigence data acquisition can be paused and the plate removed in order to collect small samples to be analyzed by orthogonal assays (i.e., measuring cytokine production by ELISA or flow cytometry; where in the EGFR-GITR-CD3 CAR T-cell experiment, INFg yield was measured with an ELISA kit (following the instructions of the manufacturer) (see for example, Step 4-Real Time Cytolysis potency assay of page 3).
Regarding step B: Xi et al teach that at key time points xCELLigence data acquisition can be paused and the plate removed in order to collect small samples to be analyzed by orthogonal assays (i.e., measuring cytokine production by ELISA or flow cytometry; where in the EGFR-GITR-CD3 CAR T-cell experiment, INFg yield was measured with an ELISA kit (following the instructions of the manufacturer) (see for example, Step 4-Real Time Cytolysis potency assay of page 3).
Regarding step C: Xi et al do not teach normalization of the cytokine data.
However, Goedhart teaches that a definition of normalization would be “the rescaling of data to facilitate comparison”. While the examples explicitly discussed by Goedhart use experimental data from fluorescence spectroscopy or imaging, rescaling/normalization methods are widely applied to all sorts of data (see for example, paragraph 1 of page 1). Goedhart further teaches that normalization of values based on the maximal value is common for the rescaling of absorbance and emission spectra from spectroscopy (citing to Mastop et al, 2017 as providing further examples). The shape of a spectrum is usually the feature of interest instead of their amplitude. The normalization is done by dividing each value by the maximal value, to enable the comparison of spectral shapes (see for example, page 4).
It would have been prima facie obvious to the person of ordinary skill in the art to arrive at the claimed invention from the disclosures of the combined references before the effective filing date of the claimed invention. The artisan would have been motivated to make and use the potency assay for CAR T cells of ‘856 and Xi et al using IFNgamma (IFNg) release as a measure of potency because Xi et al teach that determining the potency of a CAR T cell, which is taught to be a matter of serious importance.. The artisan would have found it obvious to modify the assay of Xi et al to include normalization of the cytokine (IFNg) release data to the maximum observed value to facilitate comparison of the different conditions (the titrated ratio of cells to target represented in the plurality of incubations) as taught by Goedhart. The artisan would have had a reasonable expectation of success based on the cumulative disclosures of these prior art references prior to the effective filing date.
Regarding claim 4, as discussed above, the assay of ‘856 as modified by Xi et al and Goedhart uses a set/constant number of cells (reading on the instantly recited constant number as supported by the text of paragraph 0076 at page 30 of the instant specification) for a plurality of incubations where the concentration of the target (receptor-stimulating agent) is varied (titrated) in different wells of the E-plate for measurement of IFNg release by ELISA, generating a plurality of titrated ratios.
Regarding claim 5, Xi et al teach that, in the assay, residual media is removed from the wells prior to addition of 100 µL of serially diluted effector CAR T cells or other control cells (i.e. Mock CAR T cells) to achieve the desired E:T ratios (see for example, Step 4-Real Time Cytolysis potency assay of page 3), where the technology underlying the assay has demonstrated reliable function across a large dynamic range (with E:T ratios from 20:1 to 1:20). Thus, the artisan would have understood that Xi et al are titrating the E: T ratios in the assay by varying the number of effector (CAR containing) cells relative to a fixed concentration of target (recombinant receptor stimulating agent). Additionally, figure 1, at step 3 specifically shows the E: T ratios of 0:1, 0.1:1, 0.2:1, and 1:1, which clearly shows a fixed concertation of target and a varied amount of effector cells to titrate the E:T ratios (see page5 at figure 1, for example).
Regarding claim 18, Xi et al teach the assay comprising 3 or more incubations (see for example, figure 1 showing 4 incubations of the cells at differing E:T ratios at page 5 and figure 4 showing 4 incubations of different conditions at page 6).
Regarding claims 24-25, as noted above, Xi et al teach measurement of IFNg as the receptor-dependent activity (a measure of CAR T cell potency).
Regarding claim 36, Xi et al teach the development and production of potent CAR T-cells targeting antigens with unique or preferential expression on solid and liquid tumor cells. xCELLigence utilizes specialized microtiter plates (E-Plates) that contain gold biosensors embedded in the bottom of each well. Working with either adherent solid tumor cells, or liquid cancer cells that have been tethered using specific antibodies, these biosensors monitor in real-time CAR T cell-induced changes in target cell (see for example, pages 1-2). The artisan would understand this disclosure to mean that the CAR T cell is targeting the target cell by binding between the CAR (recombinant receptor) and a surface expressed target antigen on the immobilized target cell (or a fragment thereof).
Regarding claim 37, the instant specification provides that exemplary recombinant receptor stimulating agents include antigens (e.g., purified or recombinant antigens) of the recombinant receptor (see paragraph 0077 at page 31)…where in some embodiments, the antigen is or includes…CD19…(see paragraph 0090 at pages 38-39). Where there is no preclusive definition provided, the embodiment of Xi et al where the immobilized receptor stimulating agent is a target cell, said target cell being an adherent cell, such as a HeLa cell (advantageously allowing for examination of therapeutic cell potency against liquid tumor cells without the need of a tethering agent using a readily available cell source/product) genetically engineered to stably express one or more tumor antigens, such as CD19, is deemed to read upon the recitation that the receptor stimulating agent comprises a recombinant antigen (see for example, page 7) where the therapeutic cell is a CAR T-cell binding CD19, which are taught to be known in the art with certain CD19 CAR-T cells having gained FDA approval for treating various cancers (with the understanding that a chimeric antigen receptor is by nature a recombinant receptor) (see for example, page 1).
It would have been prima facie obvious to the person of ordinary skill in the art to arrive at the claimed invention from the disclosures of the combined references before the effective filing date of the claimed invention. The artisan would have been motivated to make and use the potency assay of ‘856 as modified by Xi et al and Goedhart for CAR T cells of Xi et al in view of Goedhart in order to determine the potency of a CAR T cell for non-adherent cells such as certain tumor cells, using a readily available cell source that obviates the need for a tethering agent, thus simplifying the assay. The particular antigen utilized is a matter of routine optimization for the artisan to select an antigen that the therapeutic cell recognizes/binds to determine the potency pf the therapeutic cell composition against a desired target in an optimally streamlined assay (see MPEP § 2144.05). The artisan would have had a reasonable expectation of success based on the cumulative disclosures of these prior art references prior to the effective filing date.
Regarding claims 40-41, ‘856 claims that the plurality of incubations are performed in a multi-well plate (see claims 112-114 of ‘856). Additionally, as noted above, Xi et al teach that the receptor-stimulating agent is immobilized to the wellplate (E plate) either by expression of the agent on an adherent cell (reading upon immobilization in the absence of a preclusive definition) of via a tethering agent. The surface of the E plate/wellplate upon which the receptor-stimulating agent is immobilized reads upon the recited surface of the vessel which the plurality of incubations are performed because the incubations occur in the wells, wherein the agent is immobilized.
Regarding claim 43, ‘856 claims that the recombinant receptor is a CAR (see claim 173 of ‘856). Additionally, as discussed above, Xi et al teach a CAR T cell potency assay wherein the target (recombinant receptor-stimulating agent) is expressed on the surface of a cell (said cell reading upon an antigen-expressing cell).
Regarding claim 51, ‘856 claims that the effector cell composition comprises primary cells from a subject (see exemplary claim 101 of ‘856).
Regarding claim 54, ‘856 claims that the effector cell composition comprises
CD3+ T cells (see exemplary claim 109 of ‘856).
Regarding claim 55, ‘856 claims that the effector cell composition comprises
CD4+ T cells and CD8+ T cells (see exemplary claim 110 of ‘856).
Regarding claim 56, ‘856 claims that the recombinant receptor is a CAR (see claim 173 of ‘856). Additionally, as discussed above, the assay of Xi et al uses T cells wherein the recombinant receptor is a CAR.
Regarding claim 58, ‘856 claims that the plurality of incubations are performed in a multi-well plate (see claims 112-114 of ‘856). Additionally, as discussed above, the assay of Xi et al uses an e-plate having multiple wells wherein the plurality of incubations occur, said E-plate reading upon the recitation of a multi-well plate.
Regarding claim 66, as discussed above, Xi et al teach that at key time points xCELLigence data acquisition can be paused and the plate removed in order to collect small samples to be analyzed by orthogonal assays (i.e., measuring cytokine production by ELISA or flow cytometry; where in the EGFR-GITR-CD3 CAR T-cell experiment, INFg yield was measured with an ELISA kit (following the instructions of the manufacturer) (see for example, Step 4-Real Time Cytolysis potency assay of page 3).
Regarding claim 71, Xi et al teach comparison of CD22-CAR T cells to negative controls (untransduced T cells and Mock CAR T cells) (see for example, paragraph 2 of page 4). The Mock CAR T cell control is deemed to be an embodiment encompassed by the therapeutic cell compositions (having a recombinant receptor such as a CAR) as instantly recited. The artisan would have found it obvious to modify the assay of the combined prior art to include a plurality of incubations for two or more therapeutic cell compositions in order to compare a test composition to one or more controls or to compare multiple test compositions to select for the cell with optimal activation/stimulation in response to the stimulating agent (as measured by IFNg release).
Claim(s) 2, 60, and 67-70 is/are provisionally rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1-185 of copending Application No. 19/475,856 (‘856) in view of Xi et al and Goedhart, as applied to claims 1, 4-5, 18, 24-25, 36-37, 40-41, 43, 51, 54-56, 58, 66, and 71 above, in further view of Carney (Relative Potency, BMG LabTech, obtained from: https://www.bmglabtech.com/en/blog/relative-potency/ (posted/pub 2019)).
The claims, while not verbatim, are directed to overlapping subject matter, namely assays to determine potency/relative potency of therapeutic cell compositions.
This is a provisional nonstatutory double patenting rejection.
Regarding claim 2, ‘856, Xi et al, and Goedhart teach and make obvious the method of instant claim 1.
While ‘856 claims “determining, based on the cytotoxic activity measured for each of the plurality of incubations, a titrated ratio that results in a half-maximal cytotoxic activity of the effector cell composition” (see part c of claim of ‘856 1 as exemplary), the combined references do not explicitly teach determination of a half-maximal (EC50) receptor-dependent activity that is cytokine production or expression (IFNg release).
However, Carney teaches that the concentration at which 50% of the response is observed, is known as the EC or IC value (see for example, page 1). Carney further teaches that to quantify relative potency, the substances being compared are typically assayed across a range of concentrations at which the effect of the compound is quantified (a dose-response assay). There are a wide range of assays that allow the quantification of the effect of a compound, and the most appropriate option often depends of the characteristics and action of the compound itself. This measurement can include quantifying the extent of binding of a ligand to a receptor, the downstream intra-cellular response, or a change in the level of gene expression. Microplate readers such as those from BMG LABTECH provide a flexible platform on which to achieve high throughput measurement of many of these assay techniques. the concentration at which 50% of the response is observed can be determined. This is known as the EC50 or IC50 value, and can be used to compare the effectiveness of a compound. Many software packages, including the MARS data analysis software included with BMG LABTECH microplate readers, are capable of fitting curves to data and providing an EC50 value.
It would have been prima facie obvious to the person of ordinary skill in the art to arrive at the claimed invention from the disclosures of the combined references before the effective filing date of the claimed invention. The artisan would have been motivated to make and use the potency assay of Xi and Goedhart et al as modified by Carney to determine the EC50 (half-maximal receptor-dependent activity) because Carney teaches this value can be used to compare the effectiveness of a compound, such as a therapeutic CAR T cell composition as motivated by the combination of Xi et al, Goedhart, and Carney. The artisan would have had a reasonable expectation of success based on the cumulative disclosures of these prior art references prior to the effective filing date.
Regarding claim 60, ‘856 claims the assay method (see exemplary ‘856 claims 1-3) further comprising determining, based on the titrated ratio that results in the half-maximal cytotoxic activity of the effector cell composition, a dose of cells of the effector composition for administering to a subject in need thereof. Where the combined reference make obvious measurement of IFNg release as the activity to be measured as a measure of relative potency/potency, the artisan would have found it obvious to determine a dose of the therapeutic cell composition to be administered to a subject in need thereof based on the titrated ratio that results in the half-maximal receptor-dependent activity of the therapeutic cell (effector cell) composition.
Regarding claim 67, ‘856 claims determining a relative potency of the effector
cell composition by comparing the titrated ratio resulting in the half-maximal cytotoxic activity of the effector cell composition to a titrated ratio resulting in a half-maximal cytotoxic activity of a reference standard (see claims 1-2 of ‘856 as exemplary). It is noted that the instant specification provides that an exemplary embodiment of a reference standard is a different therapeutic cell composition (paragraph 0202 at page 80 of the instant specification). Xi et al teach comparison of CD22-CAR T cells to negative controls (untransduced T cells and Mock CAR T cells) (see for example, paragraph 2 of page 4). The Mock CAR T cells of Xi et al are deemed to read upon the recited ‘reference standard’ and the measurement of IFNg release from said negative controls reads upon the receptor-dependent activity of the reference standard (noting that IFNg release is an equivalent measure of potency to ‘856’s recited cytotoxic activity in light of the cited prior art, namely Xi et al motivating this measurement as indicative of activation of CAR T cells, indicating their potency). Note that Xi et al teach that IFNg may be measured by ELISA as a surrogate for T cell activation as part of the potency assay (where a T cell must be activated prior to exerting a therapeutic effect).
It would have been prima facie obvious to the person of ordinary skill in the art to arrive at the claimed invention from the disclosures of the combined references before the effective filing date of the claimed invention. The artisan would have been motivated to make and use the potency assay of ‘856 and Xi and Goedhart et al as modified by Carney to determine the relative potency (as a measure of IFNg release using ELISA corresponding to the therapeutic cell composition (such as the CD22-CAR T cell of Xi et as compared to the measurement of IFNg release using ELISA corresponding to one or both or the negative controls taught by Xi et al) in order to determine that the effect of the test condition (the therapeutic cell compositing) is a true observed effect. The artisan would have had a reasonable expectation of success based on the cumulative disclosures of these prior art references prior to the effective filing date.
Regarding claim 68, ‘856 claims the method of any of claims 1-13 and 43-116, further comprising determining, based on the titrated ratio that results in the half-maximal cytotoxic activity (where, as iterated above, IFNg release is an equivalent measure of potency where the effector cell composition comprises CAR T cells) of the effector cell composition, a dose of cells of the effector composition for administering to a subject in need thereof (see exemplary claims 1-3 and 117 of ‘856).
Regarding claim 69, ‘856 claims the method (of exemplary claims 1-3) wherein the activity measured (noting that the IFNg release of the prior art cited herein would be an obvious equivalent of cytotoxic activity to be measured for potency, as discussed above) comprises a linear dose-response range (see exemplary claims 1-3 and 96 of ‘856).
Regarding claim 70, ‘856 claims the method wherein the activity measured comprises a linear dose-response range, wherein the dose-response curve comprises a lower asymptote
for the cytotoxic activity measured (noting that the IFNg release of the prior art cited herein would be an obvious equivalent of cytotoxic activity to be measured for potency, as discussed above) and an upper asymptote for the cytotoxic activity of the effector cell
composition (see exemplary claims 1-3 and 96-97 of ‘856).
Claim(s) 38-39 is/are provisionally rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1-185 of copending Application No. 19/475,856 (‘856) in view of Xi et al and Goedhart, as applied to claims 1, 4-5, 18, 24-25, 36-37, 40-41, 43, 51, 54-56, 58, 66, and 71 above, in further view of Hauskins et al (WO2018023100 A2).
The claims, while not verbatim, are directed to overlapping subject matter, namely assays to determine potency/relative potency of therapeutic cell compositions.
This is a provisional nonstatutory double patenting rejection.
Regarding claims 38-39, Xi et al teach that measurement of IFNg production is a surrogate of T-cell activation (see for example, the final paragraph of page 4).
The combined references do not teach that the antigen is an anti-idiotypic antibody.
However, Hauskins et al teach anti-idiotype antibodies that specifically recognize anti-CD19 antibody moieties, in particular, anti-CD19 antibody moieties present in recombinant receptors, including chimeric antigen receptors (CARs). The disclosure further relates to uses of anti-idiotype antibodies for specifically identifying and/or selecting cells expressing such recombinant receptors, such as anti-CD19 CAR T cells. The disclosure further relates to uses of anti-idiotype antibodies for specifically activating such cells (see for example, the abstract). Hauskins et al further teach that, as shown in FIG. 10A, intracellular cytokine levels of TNFa, IFNy and IL2 cytokines were induced in CAR+ T cells (EGFRt+), but not in CAR- T cells (EGFR ), when the cells were cultured in the presence of the anti-ID B-1 conjugated beads. In this study, the extent of stimulation observed in the presence of anti-ID conjugated beads was similar to stimulation of CAR+ T cells using antigen-expressing K562-CD19 cells, which is an alternative CAR-specific stimulation reagent (FIG. 10B). These results demonstrated that anti-ID conjugated to beads are agonistic and specifically stimulate T cells expressing a CAR having an antigen-binding domain recognized by the anti-ID antibody. Further, the immobilized anti-idiotypic antibody reagent provides for a better CAR-specific stimulation reagent compared to cell lines, which require cell culture and are prone to lot to lot variability (see for example, paragraph 0587 and paragraph 0054 at pages and 14, respectively) where the anti-ID antibody may be immobilized to a solid support (see for example, paragraph 0060 at page 16).
It would have been prima facie obvious to the person of ordinary skill in the art to arrive at the claimed invention from the disclosures of the combined references before the effective filing date of the claimed invention. The artisan would have been motivated to make and use the potency assay of Xi and Goedhart et al as modified by Hauskins et al to use and anti-idiotypic antibody as the immobilized receptor-stimulating agent because Hauskins et al teach that this anti-ID antibody provides for a better CAR-specific stimulation reagent compared to cell lines (prone to variability/quality control issues) where the activation of the T-cell, as measured by IFNg release by the CAR T-cells, where the activation potential of the cell would have been reasonably understood to represent a marker of potency of the therapeutic cell composition CAR T-cell). The artisan would have had a reasonable expectation of success based on the cumulative disclosures of these prior art references prior to the effective filing date.
Claim(s) 1, 4-5, 18, 24-25, 36-37, 40-41, 43, 51, 54-56, 58, 66, and 71 is/are provisionally rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1-10, 18, 20, 22-25, 34-37, and 68 of copending Application No. 18/689,947 (‘947) in view of Xi et al (J Vis Exp. 2019 Nov 12;(153). doi: 10.3791/5903) in view of Goedhart (Data manipulation? It’s normal(izaion)!, The Node, obtained from: https://thenode.biologists.com/data-normalization/research/ (posted 2019)).
The claims of ‘947 and the instant claims, while not verbatim, are directed to overlapping potency assays/methods for assessing potency.
The rejections are provisional.
Regarding claim 1, ‘947 claims a method for assessing potency of TILs comprising: coculturing TILs and immortalized cells, wherein the immortalized cells comprise a molecule that activates a T cell; and assessing potency of the TILs (see claims 1 and 68 of ‘947).
‘947 does not teach that the therapeutic cell/cell whose potency is being assayed releases IFNg which is measured as a receptor-dependent activity indirectly indicative of potency or normalizing the receptor-dependent activity data.
Regarding claim 1, Xi et al teach a quantitative real-time in vitro cytolysis assay system to evaluate the potency of chimeric antigen receptor (CAR) T cells targeting liquid and solid tumor cells. The in vitro potency of these CAR T cells is then evaluated in real-time using the highly sensitive impedance-based xCELLigence assay. CAR T-cells against BCMA, CD-19, CD20, and CD22 are known in the art for treating cancer such as hematologic malignancies (where the CAR T cell may be autologous or allogenic). Xi et al teach that there is a critical need for the development of solid tumor-specific CAR T cells which can overcome these barriers to efficacy and the problem of "on target-off tumor" toxicity. While a multitude of in vitro and in vivo approaches are warranted in the design and testing of CAR T cells, a robust and predictive in vitro potency assay is of primary importance. In order to assess the potency of CAR T cells, various in vitro methods have been developed, many of which measure surrogate markers such as cytokines that are released by the CAR T cells as they kill the target cells (see for example, page 1). Alternative assays, which measure byproducts of CAR T-cell interaction with target cells as an indication of potency, include the quantitation of various cytokines released by CAR T cells using either flow cytometry-based methods or enzyme-linked immunosorbent assays (see for example, the final paragraph of page 1 bridging page 2). Xi et al teach that methods of genetically engineering T cells with manufactured TCRs/CARs are known in the art and that the potency assay of Xi et al is a simple functional assay and can be advantageously used in conjunction with genetic engineering techniques to design optimal and efficacious CARs in a high-throughput fashion (see for example, page 2 and paragraph 4 of the Discussion section on page 7).
Regarding step (a): Xi et al teach that previously frozen PBMCs are activated and transfected to obtain engineered CAR T-cells (see for example steps 1-Generation of CAR-encoding Lentivirus and 2- Generation and expansion of CAR T cells under the Protocol heading at page 2). Target cells (reading on the recombinant receptor stimulating agent and ‘target’ of the titrated effector (E): target (T) ratio as instantly recited) are plated onto the wells of the E-plate. The cells may be adherent cells (which would be understood to be immobilized onto the E plate surface in the absence of a preclusive definition). Residual media is removed from the wells prior to addition of 100 µL of serially diluted effector CAR T cells (reading on the ‘effector’ of the titrated effector (E): target (T) ratio as instantly recited) or other control cells (i.e. Mock CAR T cells) to achieve the desired E:T ratios (see for example, Step 4-Real Time Cytolysis potency assay of page 3). The CAR T cells/controls in serial dilutions (reading upon a plurality of incubations where the instant disclosure does not provide a closed definition of this phrase, but describes a single incubation of multiple conditions (dilutions/ CAR T cells) rather than a plurality of sequential incubations of the same set/population of cells; this is further bolstered by the subsequent wherein clause of claim 1) are allowed to sit/incubate with the target cells logically adhered to the E-plate (where if they were not adhered, the cells would have been fully removed with the removal of the media prior to addition of the CAR T cells such that no observable effect/activity of the T cells would be expected to be tested and/or measured and where, for non-adherent cells, a tethering reagent (such as an antibody specific for a surface antigen on the target cell) is used prior to plating the target cells). Xi et al teach that at key time points xCELLigence data acquisition can be paused and the plate removed in order to collect small samples to be analyzed by orthogonal assays (i.e., measuring cytokine production by ELISA or flow cytometry; where in the EGFR-GITR-CD3 CAR T-cell experiment, INFg yield was measured with an ELISA kit (following the instructions of the manufacturer) (see for example, Step 4-Real Time Cytolysis potency assay of page 3).
Regarding step B: Xi et al teach that at key time points xCELLigence data acquisition can be paused and the plate removed in order to collect small samples to be analyzed by orthogonal assays (i.e., measuring cytokine production by ELISA or flow cytometry; where in the EGFR-GITR-CD3 CAR T-cell experiment, INFg yield was measured with an ELISA kit (following the instructions of the manufacturer) (see for example, Step 4-Real Time Cytolysis potency assay of page 3).
Regarding step C: Xi et al do not teach normalization of the cytokine data.
However, Goedhart teaches that a definition of normalization would be “the rescaling of data to facilitate comparison”. While the examples explicitly discussed by Goedhart use experimental data from fluorescence spectroscopy or imaging, rescaling/normalization methods are widely applied to all sorts of data (see for example, paragraph 1 of page 1). Goedhart further teaches that normalization of values based on the maximal value is common for the rescaling of absorbance and emission spectra from spectroscopy (citing to Mastop et al, 2017 as providing further examples). The shape of a spectrum is usually the feature of interest instead of their amplitude. The normalization is done by dividing each value by the maximal value, to enable the comparison of spectral shapes (see for example, page 4).
It would have been prima facie obvious to the person of ordinary skill in the art to arrive at the claimed invention from the disclosures of the combined references before the effective filing date of the claimed invention. The artisan would have been motivated to make and use the potency assay of ‘947 as modified by Xi et al and Goedhart for CAR T cells of Xi et al using IFNgamma release as a measure of potency in light of the cited teachings of Xi et al. The artisan would have found it obvious to modify the assay of ‘947 and Xi et al to include normalization of the cytokine (IFNg) release data to the maximum observed value in order to facilitate comparison of the different conditions (the titrated ration of cells to target represented in the plurality of incubations) as taught by Goedhart. The artisan would have had a reasonable expectation of success based on the cumulative disclosures of these prior art references prior to the effective filing date.
Regarding claim 4, as discussed above, the assay of Xi et al uses a set/constant number of cells (reading on the instantly recited constant number as supported by the text of paragraph 0076 at page 30 of the instant specification) for a plurality of incubations where the concentration of the target (receptor-stimulating agent) is varied (titrated) in different wells of the E-plate for measurement of IFNg release by ELISA, generating a plurality of titrated ratios.
Regarding claim 5, Xi et al teach that, in the assay, residual media is removed from the wells prior to addition of 100 µL of serially diluted effector CAR T cells or other control cells (i.e. Mock CAR T cells) to achieve the desired E:T ratios (see for example, Step 4-Real Time Cytolysis potency assay of page 3), where the technology underlying the assay has demonstrated reliable function across a large dynamic range (with E:T ratios from 20:1 to 1:20). Thus, the artisan would have understood that Xi et al are titrating the E: T ratios in the assay by varying the number of effector (CAR containing) cells relative to a fixed concentration of target (recombinant receptor stimulating agent). Additionally, figure 1, at step 3 specifically shows the E: T ratios of 0:1, 0.1:1, 0.2:1, and 1:1, which clearly shows a fixed concertation of target and a varied amount of effector cells to titrate the E:T ratios (see page5 at figure 1, for example).
Regarding claim 18, Xi et al teach the assay comprising 3 or more incubations (see for example, figure 1 showing 4 incubations of the cells at differing E:T ratios at page 5 and figure 4 showing 4 incubations of different conditions at page 6).
Regarding claims 24-25, as noted above, Xi et al teach measurement of IFNg as the receptor-dependent activity (a measure of CAR T cell potency).
Regarding claim 36, Xi et al teach the development and production of potent CAR T-cells targeting antigens with unique or preferential expression on solid and liquid tumor cells. xCELLigence utilizes specialized microtiter plates (E-Plates) that contain gold biosensors embedded in the bottom of each well. Working with either adherent solid tumor cells, or liquid cancer cells that have been tethered using specific antibodies, these biosensors monitor in real-time CAR T cell-induced changes in target cell (see for example, pages 1-2). The artisan would understand this disclosure to mean that the CAR T cell is targeting the target cell by binding between the CAR (recombinant receptor) and a surface expressed target antigen on the immobilized target cell (or a fragment thereof).
Regarding claim 37, the instant specification provides that exemplary recombinant receptor stimulating agents include antigens (e.g., purified or recombinant antigens) of the recombinant receptor (see paragraph 0077 at page 31)…where in some embodiments, the antigen is or includes…CD19…(see paragraph 0090 at pages 38-39). Where there is no preclusive definition provided, the embodiment of Xi et al where the immobilized receptor stimulating agent is a target cell, said target cell being an adherent cell, such as a HeLa cell (advantageously allowing for examination of therapeutic cell potency against liquid tumor cells without the need of a tethering agent using a readily available cell source/product) genetically engineered to stably express one or more tumor antigens, such as CD19, is deemed to read upon the recitation that the receptor stimulating agent comprises a recombinant antigen (see for example, page 7) where the therapeutic cell is a CAR T-cell binding CD19, which are taught to be known in the art with certain CD19 CAR-T cells having gained FDA approval for treating various cancers (with the understanding that a chimeric antigen receptor is by nature a recombinant receptor) (see for example, page 1).
It would have been prima facie obvious to the person of ordinary skill in the art to arrive at the claimed invention from the disclosures of the combined references before the effective filing date of the claimed invention. The artisan would have been motivated to make and use the potency assay for CAR T cells of Xi et al in view of Goedhart in order to determine the potency of a CAR T cell for non-adherent cells such as certain tumor cells, using a readily available cell source that obviates the need for a tethering agent, thus simplifying the assay. The particular antigen utilized is a matter of routine optimization for the artisan to select an antigen that the therapeutic cell recognizes/binds to determine the potency pf the therapeutic cell composition against a desired target in an optimally streamlined assay (see MPEP § 2144.05). The artisan would have had a reasonable expectation of success based on the cumulative disclosures of these prior art references prior to the effective filing date.
Regarding claims 40-41, as noted above, Xi et al teach that the receptor-stimulating agent is immobilized to the wellplate (E plate) either by expression of the agent on an adherent cell (reading upon immobilization in the absence of a preclusive definition) of via a tethering agent. The surface of the E plate/wellplate upon which the receptor-stimulating agent is immobilized reads upon the recited surface of the vessel which the plurality of incubations are performed because the incubations occur in the wells, wherein the agent is immobilized.
Regarding claim 43, as discussed above, Xi et al teach a CAR T cell potency assay wherein the target (recombinant receptor-stimulating agent) is expressed on the surface of a cell (said cell reading upon an antigen-expressing cell).
Regarding claim 56, as discussed above, the assay of Xi et al uses T cells wherein the recombinant receptor is a CAR.
Regarding claim 58, as discussed above, the assay of Xi et al uses an e-plate having multiple wells wherein the plurality of incubations occur, said E-plate reading upon the recitation of a multi-well plate.
Regarding claim 66, as discussed above, Xi et al teach that at key time points xCELLigence data acquisition can be paused and the plate removed in order to collect small samples to be analyzed by orthogonal assays (i.e., measuring cytokine production by ELISA or flow cytometry; where in the EGFR-GITR-CD3 CAR T-cell experiment, INFg yield was measured with an ELISA kit (following the instructions of the manufacturer) (see for example, Step 4-Real Time Cytolysis potency assay of page 3).
Regarding claim 71, Xi et al teach comparison of CD22-CAR T cells to negative controls (untransduced T cells and Mock CAR T cells) (see for example, paragraph 2 of page 4). The mock CAR T cell control is deemed to be an embodiment encompassed by the therapeutic cell compositions (having a recombinant receptor such as a CAR) as instantly recited. The artisan would have found it obvious to modify the assay of the combined prior art to include a plurality of incubations for two or more therapeutic cell compositions in order to compare a test composition to one or more controls or to compare multiple test compositions to select for the cell with optimal activation/stimulation in response to the stimulating agent (as measured by IFNg release).
Claim(s) 2 and 67 is/are provisionally rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1-10, 18, 20, 22-25, 34-37, and 68 of copending Application No. 18/689,947 (947) in view of Xi et al and Goedhart, as applied to claims 1, 4-5, 18, 24-25, 36-37, 40-41, 43, 51, 54-56, 58, 66, and 71 above, in further view of Carney (Relative Potency, BMG LabTech, obtained from: https://www.bmglabtech.com/en/blog/relative-potency/ (posted/pub 2019)).
The claims of ‘947 and the instant claims, while not verbatim, are directed to overlapping potency assays/methods for assessing potency.
The rejections are provisional.
Regarding claim 2, ‘947, Xi et al, and Goedhart teach and make obvious the method of instant claim 1.
The combined references do not explicitly teach determination of a half-maximal (EC50) receptor-dependent activity (IFNg release).
However, Carney teaches that the concentration at which 50% of the response is observed, is known as the EC or IC value (see for example, page 1). Carney further teaches that to quantify relative potency, the substances being compared are typically assayed across a range of concentrations at which the effect of the compound is quantified (a dose-response assay). There are a wide range of assays that allow the quantification of the effect of a compound, and the most appropriate option often depends of the characteristics and action of the compound itself. This measurement can include quantifying the extent of binding of a ligand to a receptor, the downstream intra-cellular response, or a change in the level of gene expression. Microplate readers such as those from BMG LABTECH provide a flexible platform on which to achieve high throughput measurement of many of these assay techniques. the concentration at which 50% of the response is observed can be determined. This is known as the EC50 or IC50 value, and can be used to compare the effectiveness of a compound. Many software packages, including the MARS data analysis software included with BMG LABTECH microplate readers, are capable of fitting curves to data and providing an EC50 value.
It would have been prima facie obvious to the person of ordinary skill in the art to arrive at the claimed invention from the disclosures of the combined references before the effective filing date of the claimed invention. The artisan would have been motivated to make and use the potency assay of Xi and Goedhart et al as modified by Carney to determine the EC50 (half-maximal receptor-dependent activity) because Carney teaches this value can be used to compare the effectiveness of a compound, such as a therapeutic CAR T cell composition as motivated by the combination of Xi et al, Goedhart, and Carney. The artisan would have had a reasonable expectation of success based on the cumulative disclosures of these prior art references prior to the effective filing date.
Regarding claim 67, the specification states that exemplary reference standards may be a different therapeutic cell composition (paragraph 0202 at page 80 of the instant specification). Xi et al teach comparison of CD22-CAR T cells to negative controls (untransduced T cells and Mock CAR T cells) (see for example, paragraph 2 of page 4). The negative control Mock CAR T cells (being an encompassed embodiment of a different therapeutic cell composition which is an encompassed embodiment of a reference standard) of Xi et al are deemed to read upon the recited ‘reference standard’ and the measurement of IFNg release from said Mock CAR T cells reads upon the receptor-dependent activity of the reference standard. Note that Xi et al teach that IFNg may be measured by ELISA as a surrogate for T cell activation as part of the potency assay (where a T cell must be activated prior to exerting a therapeutic effect).
It would have been prima facie obvious to the person of ordinary skill in the art to arrive at the claimed invention from the disclosures of the combined references before the effective filing date of the claimed invention. The artisan would have been motivated to make and use the potency assay of Xi and Goedhart et al as modified by Carney to determine the relative potency (as a measure of IFNg release using ELISA corresponding to the therapeutic cell composition (such as the CD22-CAR T cell of Xi et as compared to the measurement of IFNg release using ELISA corresponding to the negative control Mock CAR T cells taught by Xi et al) in order to determine that the effect of the test condition (the therapeutic cell compositing) is a true observed effect. The artisan would have had a reasonable expectation of success based on the cumulative disclosures of these prior art references prior to the effective filing date.
Claim(s) 38-39 is/are provisionally rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1-10, 18, 20, 22-25, 34-37, and 68 of copending Application No. 18/689,947 (947) in view of Xi et al and Goedhart, as applied to claims 1, 4-5, 18, 24-25, 36-37, 40-41, 43, 51, 54-56, 58, 66, and 71 above, in further view of Hauskins et al (WO2018023100 A2)
The claims of ‘947 and the instant claims, while not verbatim, are directed to overlapping potency assays/methods for assessing potency.
The rejections are provisional.
Regarding claims 38-39, Xi et al teach that measurement of IFNg production is a surrogate of T-cell activation (see for example, the final paragraph of page 4).
The combined references do not teach that the antigen is an anti-idiotypic antibody.
However, Hauskins et al teach anti-idiotype antibodies that specifically recognize anti-CD19 antibody moieties, in particular, anti-CD19 antibody moieties present in recombinant receptors, including chimeric antigen receptors (CARs). The disclosure further relates to uses of anti-idiotype antibodies for specifically identifying and/or selecting cells expressing such recombinant receptors, such as anti-CD19 CAR T cells. The disclosure further relates to uses of anti-idiotype antibodies for specifically activating such cells (see for example, the abstract). Hauskins et al further teach that, as shown in FIG. 10A, intracellular cytokine levels of TNFa, IFNg and IL2 cytokines were induced in CAR+ T cells (EGFRt+), but not in CAR- T cells (EGFR ), when the cells were cultured in the presence of the anti-ID B-1 conjugated beads. In this study, the extent of stimulation observed in the presence of anti-ID conjugated beads was similar to stimulation of CAR+ T cells using antigen-expressing K562-CD19 cells, which is an alternative CAR-specific stimulation reagent (FIG. 10B). These results demonstrated that anti-ID conjugated to beads are agonistic and specifically stimulate T cells expressing a CAR having an antigen-binding domain recognized by the anti-ID antibody. Further, the immobilized anti-idiotypic antibody reagent provides for a better CAR-specific stimulation reagent compared to cell lines, which require cell culture and are prone to lot to lot variability (see for example, paragraph 0587 and paragraph 0054 at pages and 14, respectively) where the anti-ID antibody may be immobilized to a solid support (see for example, paragraph 0060 at page 16).
It would have been prima facie obvious to the person of ordinary skill in the art to arrive at the claimed invention from the disclosures of the combined references before the effective filing date of the claimed invention. The artisan would have been motivated to make and use the potency assay of ‘947, Xi, and Goedhart et al as modified by Hauskins et al to use and anti-idiotypic antibody as the immobilized receptor-stimulating agent because Hauskins et al teach that this anti-ID antibody provides for a better CAR-specific stimulation reagent compared to cell lines (prone to variability/quality control issues) where the activation of the T-cell, as measured by IFNg release by the CAR T-cells, where the activation potential of the cell would have been reasonably understood to represent a marker of potency of the therapeutic cell composition CAR T-cell). The artisan would have had a reasonable expectation of success based on the cumulative disclosures of these prior art references prior to the effective filing date.
Claim(s) 51 and 54-55 is/are provisionally rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1-10, 18, 20, 22-25, 34-37, and 68 of copending Application No. 18/689,947 (947) in view of Xi et al and Goedhart, as applied to claims 1, 4-5, 18, 24-25, 36-37, 40-41, 43, 51, 54-56, 58, 66, and 71 above, in further view of Kleiveland et al (Peripheral Blood Mononuclear Cells. In: Verhoeckx K, Cotter P, López-Expósito I, et al., editors. The Impact of Food Bioactives on Health: in vitro and ex vivo models [Internet]. Cham (CH): Springer; 2015. Chapter 15. Available from: https://www.ncbi.nlm.nih.gov/books/NBK500157/ doi: 10.1007/978-3-319-16104-4_15).
The claims of ‘947 and the instant claims, while not verbatim, are directed to overlapping potency assays/methods for assessing potency.
The rejections are provisional.
Regarding claims 51 and 54-55, Xi et al teaches that the therapeutic cell composition begins with PBMCs, whereupon, after incubation with CAR T cell medium, transduction enhancement agent, and lentivirus, the cells are gated to arrive at viable/live CD3+ T cells (see for example, pages 2-3). Primary cells, absent a clear and closed definition, are understood to invoke the common parlance meaning of cells derived from living tissue, which, PBMCs being derived from peripheral blood, would mean that PBMCs are understood to comprise primary cells, even after the transfection and gating steps of Xi et al. Xi et al do not explicitly teach that the Cd3+ T cells are CD4+ and/or CD8+. However, the artisan would understand the composition resulting from the steps of Xi et al to comprise CD4+ and CD8+ T cells because Kleiveland et al evidence teachings that human peripheral blood mononuclear cells (PBMCs) are isolated from peripheral blood (understood to be primary cells) and include lymphocytes, the lymphocyte population including 70–85 % CD3 + T cells, where the CD3 + lymphocytes are composed of CD4 + and CD8 + T cells, roughly in a 2:1 ratio (see for example, section 15.1 spanning pages 161-162).
It would have been prima facie obvious to the person of ordinary skill in the art to arrive at the claimed invention from the disclosures of the combined references before the effective filing date of the claimed invention. The artisan would have been motivated to make and use the potency assay of Xi and Goedhart et al for the reasons iterated in the rejection of instant claim 1, where the artisan would have understood the therapeutic cell composition resulting from the steps of the combined assay to include primary cells, CD3+ cells, CD4+ cells, and CD8+ cells in light of the evidentiary teachings of Kleiveland et al. The artisan would have had a reasonable expectation of success based on the cumulative disclosures of these prior art references prior to the effective filing date.
Claim(s) 60 and 68-69 is/are provisionally rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1-10, 18, 20, 22-25, 34-37, and 68 of copending Application No. 18/689,947 (947) in view of Xi et al, Goedhart, and Carney as applied to claims 2 and 67 above, in further view of Warren (Br J Clin Pharmacol. 2019 Oct;85(10):2187-2193. doi: 10.1111/bcp.13949. Epub 2019 May 17.).
The claims of ‘947 and the instant claims, while not verbatim, are directed to overlapping potency assays/methods for assessing potency.
The rejections are provisional.
Regarding claim 60, the combined references do not teach dose determination based on EC50 (synonymous with ED50 (the concentration/dose yielding the effect of a half maximal response)).
However, Warren teaches that the half‐maximal point of the curve, the effective dose‐50%, or ED50, are synonymous (see for example, paragraph 2 of the Introduction at page 2187) such that the artisan would understand that the ED50 is synonymous with the instantly recited dose that results in a half-maximal activity. Warren further teaches that when choosing a medicine two aspects determine the balance between benefit and harm (risk–benefit), matching the medicine to the individual and the choice of dose. Warren teaches that knowing the relationship between dose and response allows a calculation of the dose that causes 50% of the maximal effect, the ED50 and that rational drug dosing depends on defining the ratio of the dose to the ED50 (dose resulting in half-maximal activity). The ED50 of each drug has two scales, whether the effect measured is for efficacy or safety (see for example, the abstract at page 2187). Warren further teaches that the ED50 can predict the likely effective tissue concentration and dose needed when the drug is given in vivo (see for example, paragraph 2 of the Introduction at page 2187).
It is noted that no steps are specified for how the dose of the cells of the composition for administration to a subject in need thereof is determined based upon the half-maximal recombinant receptor-dependent response.
It would have been prima facie obvious to the person of ordinary skill in the art to arrive at the claimed invention from the disclosures of the combined references before the effective filing date of the claimed invention. The artisan would have been motivated to determine the dose of therapeutic cell compositions to be administered to a subject in need thereof based on the EC50/ED50 value because Warren teaches that the ED50 can predict the likely effective tissue concentration and dose needed when the drug is given in vivo (see for example, paragraph 2 of the Introduction at page 2187). The artisan would have had a reasonable expectation of success based on the cumulative disclosures of these prior art references prior to the effective filing date.
Regarding claim 68, the combined references do not teach dose determination based on EC50 (synonymous with ED50 (the concentration/dose yielding the effect of a half maximal response)). Note that no definition is provided to specify what the potency of the therapeutic cell composition is relative to.
However, Warren teaches that when choosing a medicine two aspects determine the balance between benefit and harm (risk–benefit), matching the medicine to the individual and the choice of dose. Knowing the relationship between dose and response allows a calculation of the dose that causes 50% of the maximal effect, the ED50. Rational drug dosing depends on defining the ratio of the dose to the ED50. The ED50 of each drug has two scales, whether the effect measured is for efficacy, or safety (see for example, the abstract at page 2187). Warren further teaches that The half‐maximal point of the curve, the effective dose‐50%, or ED50, can predict the likely effective tissue concentration and dose needed when the drug is given in vivo (see for example, paragraph 2 of the Introduction at page 2187).
It is noted that no steps are specified for how the dose of the cells of the composition for administration to a subject in need thereof is determined based upon the half-maximal recombinant receptor-dependent response.
It would have been prima facie obvious to the person of ordinary skill in the art to arrive at the claimed invention from the disclosures of the combined references before the effective filing date of the claimed invention. The artisan would have been motivated to determine the dose of therapeutic cell compositions to be administered to a subject in need thereof based on the EC50/ED50 value because Warren teaches that the ED50 can predict the likely effective tissue concentration and dose needed when the drug is given in vivo (see for example, paragraph 2 of the Introduction at page 2187). The artisan would have found it obvious to look at the potency, as indirectly indicated by activation measured by IFNg release, of a therapeutic cell composition relative to a reference standard (such as T cells from the subject which are not transfected) in order to verify the enhanced efficacy of the therapeutic cell composition relative to the non-transfected control, using the EC50 to aid in determination of a dose to be administered according to the combined teachings of the cited references. The artisan would have had a reasonable expectation of success based on the cumulative disclosures of these prior art references prior to the effective filing date.
Regarding claim 69, Carney et al further teaches that the EC50 (concentration at which a half maximal effect is observed; synonymous with the concertation of the titrated ration which results in the half maximal activity as discussed in the rejection of claim 2 above) occurs on a linear portion of the sigmoidal curve of the dose-response data (see for example, figure 2 at page 2).
Warren et al, as discussed above, teach that rational drug dosing depends on defining the ratio of the dose to the ED50 (the dose at which a half maximal response if observed (see the rejection of claim 600 above) such that EC50 and ED50 would have been understood to be synonymous with the titrated ratio concentration/dose responsible for half-maximal activity of claim 67 from which claim 69 depends). The ED50 of each drug has two scales, whether the effect measured is for efficacy, or safety (see for example, the abstract at page 2187). Warren further teaches that The half‐maximal point of the curve, the effective dose‐50%, or ED50, can predict the likely effective tissue concentration and dose needed when the drug is given in vivo (see for example, paragraph 2 of the Introduction at page 2187).
As discussed above, it would have been prima facie obvious to determine the dose based on the ED50 where the artisan would have understood that the ED50 is determined by plotting dose (titrated concentrations of the therapeutic cell composition) against the response (measured IFNg release), the ED50 being pulled from the linear portion of the sigmoidal dose-response curve. The artisan would have had a reasonable expectation of success based on the cumulative disclosures of these prior art references prior to the effective filing date.
Claim(s) 70 is/are provisionally rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1-10, 18, 20, 22-25, 34-37, and 68 of copending Application No. 18/689,947 (947) in view of Xi et al, Goedhart, Carney, and Warren, as applied to claims 60 and 68-69, in further view of Little (Essentials in Bioassay Design and Relative Potency Determination, BioPharm International, Vol 29, Iss. 4, pub 04-01-2016, obtained from: https://www.biopharminternational.com/view/essentials-bioassay-design-and-relative-potency-determination).
Regarding claim 70, the combined references do not explicitly label the components of the dose-response sigmoidal curve showing the upper and lower asymptote.
However, Little teaches the ideal dose response curve is a five-point curve for parallel line analysis (linear) and a nine-point dose scheme or more for sigmoidal fits. For a sigmoidal curve, ideally it should be three points in the inactive or low response section of the curve, three points in the linear part of the curve and three points in the saturated area of the curve on the log or log 10 scale from a serial dilution. The inactive or low response section of the curve (lower line of the sigmoid curve substantially parallel to the X-axis) being the lower asymptote and the upper response in the saturated area of the curve (upper most line of the sigmoid curve substantially parallel to the X-axis) being the upper asymptote. The lower asymptote is clearly the minimal activity (response) portion and the upper asymptote is clearly the maximal activity (response portion).
It would have been prima facie obvious to the person of ordinary skill in the art to arrive at the claimed invention from the disclosures of the combined references before the effective filing date of the claimed invention. The artisan would have been motivated to have the titrated ratio encompass a lower asymptote and an upper asymptote because Little teaches that the ideal dose-response curve has a lower (minimal) and upper (maximal) asymptote. The artisan would have had a reasonable expectation of success based on the cumulative disclosures of these prior art references prior to the effective filing date.
Conclusion
No claim is allowed.
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Sadelain et al (Cancer Discov. 2013 Apr;3(4):388-98. doi: 10.1158/2159-8290.CD-12-0548. Epub 2013 Apr 2) teach that chimeric antigen receptors (CAR) are recombinant receptors that provide both antigen-binding and T-cell-activating functions.
Schaffer et al (Med. Sci. 2014, 2, 23-36; doi:10.3390/medsci2010023) teach predictability of swapping different scFvs/ligands into a CAR format.
Bipulendu et al (PLoS One. 2013;8(3):e57838. doi: 10.1371/journal.pone.0057838. Epub 2013 Mar 1) teach an anti-idiotype monoclonal antibody (mAb) to detect CD19-specific CAR T cells. This clone can be used to detect CD19-specific CAR T cells in peripheral blood mononuclear cells at a sensitivity of 1∶1,000. In clinical settings the mAb is used to inform on the immunophenotype and persistence of administered CD19-specific T cells. Thus, Bipulendu et al’s CD19-specific CAR mAb (clone no. 136.20.1) will be useful to investigators implementing CD19-specific CAR+ T cells to treat B-lineage malignancies. Bipulendu et al teach that the methodology described to develop a CAR-specific anti-idiotypic mAb could be extended to other gene therapy trials targeting different tumor associated antigens in the context of CAR-based adoptive T-cell therapy.
Jiang et al (Biom J. 2014 May;56(3):493-512. doi: 10.1002/bimj.201300123. Epub 2014 Jan 29) teach that dose-response studies are performed to investigate the potency of a compound. ED50 is the concentration of the compound that gives half-maximal response. Dose-response data are typically evaluated by using a log-logistic model that includes EC50 as one of the model parameters (see for example the abstract).
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/Ashley Gao/
Examiner, Art Unit 1678
/GREGORY S EMCH/Supervisory Patent Examiner, Art Unit 1678
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