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 .
Priority
The instant application is a national stage entry of PCT application PCT/US2022/047753, filed 04/24/2024 under 35 USC 371. Acknowledgement is made of the applicant’s claim for benefit to prior-filed U.S. provisional patent application 63/271,441, which was filed 10/25/2021.
Election/Restrictions
Applicant’s election without traverse of group I, claims 1, 4, 7, 10, 15, 16, 18, 21, 26, 39, 40, 46, 50, 64, 83, 84 and 89, drawn to a method for culturing primary human hepatocytes, in the reply filed on 08/03/2026 is acknowledged. Accordingly, claims 1, 4, 7, 10, 15, 16, 18, 21, 26, 39, 40, 46, 50, 64, 83, 84 and 89 have been considered on the merits. Claims 101, 102 and 128 are withdrawn from consideration pursuant 37 CFR 1.142(b).
Claim Objections
Claim 7 is objected to because of the following informalities: Claim 7 recites abbreviations “EGF” and ‘FGF”, these abbreviations should be spelled out at the first encounter in the claims. Appropriate correction is required.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claim 15 is rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Claim 15 recites “the expansion medium comprises N-acetylcysteine, nicotinamide, a Rho kinase inhibitor, or any combination of the foregoing” renders instant claim indefinite. It is not clear whether it means the expansion medium comprises the chemicals such as N-acetylcysteine instead of the chemicals listed in claim 1, or the limitation means the expansion medium further comprises the chemicals such as N-acetylcysteine in addition to the chemicals listed in claim 1.
Claim Interpretation
As stated above, claim 15 is indefinite. In the interest of compacted prosecution, claim 15 is interpreted as the expansion medium further comprises N-acetylcysteine, nicotinamide, a Rho kinase inhibitor, or any combination of the foregoing.
Claim Rejections - 35 USC § 102
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 the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
(a)(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention.
Claims 1, 4, 7, 10, 15, 16, 18, 26, 64, 83, 84 and 89 are rejected under 35 U.S.C. 102(a)(1) and (a)(2) as being anticipated by Clevers et al. (WO 2020/109324 A1, published 06/04/2020, cited in IDS).
Clevers et al. teach culture methods and media for in vitro expansion of hepatocytes, particularly primary hepatocytes; hepatocyte cultures and organoids obtainable and obtained by said methods; and uses of said hepatocyte cultures and organoids (Abstract).
Regarding claim 1, Clevers et al. teach a method for expanding hepatocytes in vitro, wherein the method comprises culturing hepatocytes in the hepatocyte culture medium of the invention (p3, L4-6), which enables optimally expanding primary hepatocytes while maintaining their key morphological, functional and gene expression properties (p3, L7-9), preferably wherein the primary hepatocytes are human ("PHHs", see p9, L11-12). The hepatocyte culture medium of the invention comprises Fibroblast Growth Factor (FGF), a Wnt agonist comprising an R-spondin, epidermal growth factor (EGF), hepatocyte growth factor (HGF) and a transforming growth factor beta (TGF-β) inhibitor (see p3, L24-31). According to some embodiments, the R-spondin is selected from the group consisting of: R-spondin 1(RSPO1), R-spondin 2 (RSPO2), R-spondin 3 (RSPO3), R-spondin 4 (RSPO4) (p5, L8-9). Herein the EGF, FGF and HGF are receptor tyrosine kinase ligands, and TGF-β inhibitor is an epithelial phenotype stabilizing agent. Clevers et al. also teach the cell culture medium that is used comprises any suitable basal medium (p24, L2-3). Clevers et al. teach the method further comprises contacting the primary hepatocytes and/ or the hepatocyte organoids to be expanded with an extracellular matrix (ECM) (p30, L29-30). Therefore Clevers et al. anticipate instant claim.
Regarding claims 4, 7 and 10, as discussed above, Clevers et al. teach the hepatocyte culture medium of the invention comprises Fibroblast Growth Factor (FGF), a Wnt agonist comprising an R-spondin, epidermal growth factor (EGF), hepatocyte growth factor (HGF) and a transforming growth factor beta (TGF-β) inhibitor (see p3, L24-31). According to some embodiments, the R-spondin is selected from the group consisting of: R-spondin 1(RSPO1), R-spondin 2 (RSPO2), R-spondin 3 (RSPO3), R-spondin 4 (RSPO4) (p5, L8-9). Herein the EGF, FGF and HGF are receptor tyrosine kinase ligands, and TGF-β inhibitor is an epithelial phenotype stabilizing agent.
Regarding claim 15, following the discussion above, Clevers et al. teach according to some embodiments, the hepatocyte culture medium of the invention further comprises N-acetylcysteine (p7, L20-21).
Regarding claim 16, following the discussion above, Clevers et al. teach the hepatocyte culture medium of the invention comprises Fibroblast Growth Factor (FGF), a Wnt agonist comprising an R-spondin and at least one glycogen synthase kinase 3 (GSK3) inhibitor, epidermal growth factor (EGF), hepatocyte growth factor (HGF) and a transforming growth factor beta (TGF-β) inhibitor (see p3, L24-31). This teaching reads on that the expansion medium does not contain a Rho kinase inhibitor, a Notch inhibitor, a Notch agonist, or gastrin.
Regarding claim 18, following the discussion above, Clevers et al. teach the method further comprises contacting the primary hepatocytes and/ or the hepatocyte organoids to be expanded with an extracellular matrix (ECM) (p30, L29-30). Clevers et al. teach the ECM used in accordance with the invention may be naturally occurring ECM, a commercial ECM mimicking naturally occurring ECM and/or synthetic ECM. Naturally occurring ECM is secreted by connective tissue cells and may be composed of a variety of polysaccharides, water, elastin, and glycoproteins, wherein the glycoproteins may comprise, for example, collagen, entactin (nidogen), fibronectin, and laminin (p31, 14-19).
Regarding claim 26, following the discussion above, Clevers et al. teach according to some embodiments, the hepatocyte culture medium of the invention further comprises the B27 supplement (p7, L26-27).
Regarding claim 64, Clevers et al. teach a differentiation medium for maturation of fetal hepatocytes (p13, L7-8). The differentiation medium increases maturation of the fetal-orgs and/or cells derived therefrom (p12, L30). According to some embodiments, the differentiation medium comprises the hepatocyte culture medium of the invention and at least one of dexamethasone and oncostatin M (p12, L33-35). The hepatocyte culture medium of the invention comprises Fibroblast Growth Factor (FGF), a Wnt agonist comprising an R-spondin, epidermal growth factor (EGF), hepatocyte growth factor (HGF) and a transforming growth factor beta (TGF-β) inhibitor (see p3, L24-31). The cell culture medium that is used comprises any suitable basal medium (p24, L2-3). This teaching reads on the method further comprises maturing the hepatocytes in a maturation medium comprising a basal medium for human cells to which is added one or more hepatocyte maturation supplements (i.e., herein at least one of dexamethasone and oncostatin M).
Regarding claim 83, as discussed above, Clevers et al. teach differentiating the cells of Fetal-orgs and/or single cells derived therefrom is performed by culturing the cells in a differentiation medium (p12, L27-28). Clevers et al. teach a differentiation medium for maturation of fetal hepatocytes (p13, L7-8). The differentiation medium increases maturation of the fetal-orgs and/or cells derived therefrom (p12, L30). According to some embodiments, the differentiation medium comprises the hepatocyte culture medium of the invention and at least one of dexamethasone and oncostatin M (p12, L33-35). The hepatocyte culture medium of the invention comprises Fibroblast Growth Factor (FGF), a Wnt agonist comprising an R-spondin, epidermal growth factor (EGF), hepatocyte growth factor (HGF) and a transforming growth factor beta (TGF-β) inhibitor (see p3, L24-31). The cell culture medium that is used comprises any suitable basal medium (p24, L2-3). This teaching reads on the method further comprises maturing the hepatocytes in a maturation medium comprising a basal medium for human cells to which is added one or more hepatocyte maturation supplements (i.e., herein at least one of dexamethasone and oncostatin M).
Regarding claim 84, following the discussion above, Clevers et al. teach differentiating the cells of Fetal-orgs and/or single cells derived therefrom is performed by culturing the cells in a differentiation medium (p12, L27-28), indicates that the maturation step begins immediately following the hepatocyte expansion (i.e., change the medium from expansion medium to differentiation medium).
Regarding claim 89, following the discussion above, Clevers et al. teach the differentiation medium comprises the hepatocyte culture medium of the invention and at least one of dexamethasone and oncostatin M (p12, L33-35).
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.
Claims 1, 4, 7, 10, 15, 16, 18, 21, 26, 64, 83, 84 and 89 are rejected under 35 U.S.C. 103 as being unpatentable over Clevers et al. (WO 2020/109324 A1, published 06/04/2020, cited in IDS) in view of Watanabe et al. (PLoS One. 2016 Sep 6;11(9):e0161383).
Clevers et al. teach culture methods and media for in vitro expansion of hepatocytes, particularly primary hepatocytes; hepatocyte cultures and organoids obtainable and obtained by said methods; and uses of said hepatocyte cultures and organoids (Abstract).
Regarding claim 1, Clevers et al. teach a method for expanding hepatocytes in vitro, wherein the method comprises culturing hepatocytes in the hepatocyte culture medium of the invention (p3, L4-6), which enables optimally expanding primary hepatocytes while maintaining their key morphological, functional and gene expression properties (p3, L7-9), preferably wherein the primary hepatocytes are human ("PHHs", see p9, L11-12). The hepatocyte culture medium of the invention comprises Fibroblast Growth Factor (FGF), a Wnt agonist comprising an R-spondin, epidermal growth factor (EGF), hepatocyte growth factor (HGF) and a transforming growth factor beta (TGF-β) inhibitor (see p3, L24-31). According to some embodiments, the R-spondin is selected from the group consisting of: R-spondin 1(RSPO1), R-spondin 2 (RSPO2), R-spondin 3 (RSPO3), R-spondin 4 (RSPO4) (p5, L8-9). Herein the EGF, FGF and HGF are receptor tyrosine kinase ligands, and TGF-β inhibitor is an epithelial phenotype stabilizing agent. Clevers et al. also teach the cell culture medium that is used comprises any suitable basal medium (p24, L2-3). Clevers et al. teach the method further comprises contacting the primary hepatocytes and/ or the hepatocyte organoids to be expanded with an extracellular matrix (ECM) (p30, L29-30). Therefore Clevers et al. anticipate instant claim.
Regarding claims 4, 7 and 10, as discussed above, Clevers et al. teach the hepatocyte culture medium of the invention comprises Fibroblast Growth Factor (FGF), a Wnt agonist comprising an R-spondin, epidermal growth factor (EGF), hepatocyte growth factor (HGF) and a transforming growth factor beta (TGF-β) inhibitor (see p3, L24-31). According to some embodiments, the R-spondin is selected from the group consisting of: R-spondin 1(RSPO1), R-spondin 2 (RSPO2), R-spondin 3 (RSPO3), R-spondin 4 (RSPO4) (p5, L8-9). Herein the EGF, FGF and HGF are receptor tyrosine kinase ligands, and TGF-β inhibitor is an epithelial phenotype stabilizing agent.
Regarding claim 15, following the discussion above, Clevers et al. teach according to some embodiments, the hepatocyte culture medium of the invention further comprises N-acetylcysteine (p7, L20-21).
Regarding claim 16, following the discussion above, Clevers et al. teach the hepatocyte culture medium of the invention comprises Fibroblast Growth Factor (FGF), a Wnt agonist comprising an R-spondin and at least one glycogen synthase kinase 3 (GSK3) inhibitor, epidermal growth factor (EGF), hepatocyte growth factor (HGF) and a transforming growth factor beta (TGF-β) inhibitor (see p3, L24-31). This teaching reads on that the expansion medium does not contain a Rho kinase inhibitor, a Notch inhibitor, a Notch agonist, or gastrin.
Regarding claim 18, following the discussion above, Clevers et al. teach the method further comprises contacting the primary hepatocytes and/ or the hepatocyte organoids to be expanded with an extracellular matrix (ECM) (p30, L29-30). Clevers et al. teach the ECM used in accordance with the invention may be naturally occurring ECM, a commercial ECM mimicking naturally occurring ECM and/or synthetic ECM. Naturally occurring ECM is secreted by connective tissue cells and may be composed of a variety of polysaccharides, water, elastin, and glycoproteins, wherein the glycoproteins may comprise, for example, collagen, entactin (nidogen), fibronectin, and laminin (p31, 14-19).
Regarding claim 26, following the discussion above, Clevers et al. teach according to some embodiments, the hepatocyte culture medium of the invention further comprises the B27 supplement (p7, L26-27).
Regarding claim 64, Clevers et al. teach a differentiation medium for maturation of fetal hepatocytes (p13, L7-8). The differentiation medium increases maturation of the fetal-orgs and/or cells derived therefrom (p12, L30). According to some embodiments, the differentiation medium comprises the hepatocyte culture medium of the invention and at least one of dexamethasone and oncostatin M (p12, L33-35). The hepatocyte culture medium of the invention comprises Fibroblast Growth Factor (FGF), a Wnt agonist comprising an R-spondin, epidermal growth factor (EGF), hepatocyte growth factor (HGF) and a transforming growth factor beta (TGF-β) inhibitor (see p3, L24-31). The cell culture medium that is used comprises any suitable basal medium (p24, L2-3). This teaching reads on the method further comprises maturing the hepatocytes in a maturation medium comprising a basal medium for human cells to which is added one or more hepatocyte maturation supplements (i.e., herein at least one of dexamethasone and oncostatin M).
Regarding claim 83, as discussed above, Clevers et al. teach differentiating the cells of Fetal-orgs and/or single cells derived therefrom is performed by culturing the cells in a differentiation medium (p12, L27-28). Clevers et al. teach a differentiation medium for maturation of fetal hepatocytes (p13, L7-8). The differentiation medium increases maturation of the fetal-orgs and/or cells derived therefrom (p12, L30). According to some embodiments, the differentiation medium comprises the hepatocyte culture medium of the invention and at least one of dexamethasone and oncostatin M (p12, L33-35). The hepatocyte culture medium of the invention comprises Fibroblast Growth Factor (FGF), a Wnt agonist comprising an R-spondin, epidermal growth factor (EGF), hepatocyte growth factor (HGF) and a transforming growth factor beta (TGF-β) inhibitor (see p3, L24-31). The cell culture medium that is used comprises any suitable basal medium (p24, L2-3). This teaching reads on the method further comprises maturing the hepatocytes in a maturation medium comprising a basal medium for human cells to which is added one or more hepatocyte maturation supplements (i.e., herein at least one of dexamethasone and oncostatin M).
Regarding claim 84, following the discussion above, Clevers et al. teach differentiating the cells of Fetal-orgs and/or single cells derived therefrom is performed by culturing the cells in a differentiation medium (p12, L27-28), indicates that the maturation step begins immediately following the hepatocyte expansion (i.e., change the medium from expansion medium to differentiation medium).
Regarding claim 89, following the discussion above, Clevers et al. teach the differentiation medium comprises the hepatocyte culture medium of the invention and at least one of dexamethasone and oncostatin M (p12, L33-35).
Regarding claim 21, Clevers et al. teach using ECM. In some embodiments the extracellular matrix is three-dimensional ("3D ECM"). In other embodiments, it is contemplated that the extracellular matrix is in suspension with the culture medium (p30, L31-33). Clevers et al. do not teach the culturing step is performed on a two-dimensional surface that is coated with the ECM. However, this was disclosed by Watanabe et al..
Watanabe et al. teach the expressions of laminin chains in isolated primary human hepatocytes and liver tissue, and investigated the efficacy of human recombinant laminins on hepatocyte functions in vitro, such as albumin production, hepatic transport activity, and hepatic metabolism (p2, parag 3).
Regarding claim 21, Watanabe et al. teach isolated primary human hepatocytes were seeded on plates pre-coated with laminin (10 μg/ml), EHS, or Collagen (0.3 mg/ml) (p3, “Cell culture” part), all laminin isoforms tested, laminin -111, -211, -221, -332, -411, -421, -511, and -521, retained viability, gene expressions, and functional properties of primary human hepatocytes for up to 6 days in culture, and of note, these results are comparable to hepatocytes cultured on conventionally used animal derived EHS or Collagen (p10, first paragraph of Discussion).
It would have been prima facie obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Clevers et al.’s method for expanding hepatocytes in vitro, and culture the hepatocytes on plates pre-coated with laminin isoform as taught by Watanabe et al.. The only difference regarding cell seeding between instant claim and Clevers et al.’s method for expanding hepatocytes in vitro is instant claim cultures hepatocytes on a two-dimensional surface which is coated with the ECM (i.e., laminin). Given that Watanabe et al. teach laminin isoforms retained viability, gene expressions, and functional properties of primary human hepatocytes, one of ordinary skill in the art would have substituted Clevers et al.’s method for contacting the primary hepatocytes with ECM (i.e., 3D ECM) during culture, and use laminin isoform pre-coated plate to culture primary human hepatocytes depend on their research interest or preference. This simple substitution of one known element (culturing primary human hepatocytes using laminin isoform pre-coated plate) for another known element (culturing primary human hepatocytes by contacting the primary hepatocytes with ECM (i.e., 3D ECM)) is likely to be obvious when predictable results are achieved. See KSR International Co. v. Teleflex Inc., 550 U.S. 398, 415-421, USPQ2d 1385, 1395 — 97 (2007) (see MPEP § 2143, B.).
Claims 1, 4, 7, 10, 15, 16, 18, 26, 39, 40, 46, 50, 64, 83, 84 and 89 are rejected under 35 U.S.C. 103 as being unpatentable over Clevers et al. (WO 2020/109324 A1, published 06/04/2020), as applied to claims 1, 4, 7, 10, 15, 16, 18, 26, 64, 83, 84 and 89 above, in view of Zhang et al. (Cell Stem Cell. 2018 Dec 6;23(6):806-819.e4, cited in IDS).
The teaching of Clevers et al. is set forth above.
Regarding claim 39, Clevers et al. do not teach the culturing step comprises expanding plated hepatocytes (step P0) and a first passage of expanded hepatocytes (step P1). However, this was disclosed by Zhang et al. at the time of instant invention.
Zhang et al. teach defined medium conditions that allow 10,000-fold expansion of human hepatocytes (HHs)(Abstract).
Regarding claims 39 and 40, Zhang et al. teach human hepatocytes are seeded in a collagen-I-coated dish. The medium was changed to HM 10 hours after seeding and every 2 days thereafter. On day 6 of the primary culture, cells were trypsinized and then seeded in collagen-I-coated dishes. Medium was changed every 2 days (pe2, “Human hepatocyte culture” part). This teaching reads on the culturing of human hepatocytes on coated two-dimensional surface, and has a 6-day primary culture period (step P0) and a first passage of expanded hepatocytes (step P1), as recited in instant claim 39. In addition, Zhang et al. also teach human hepatocytes are seeded and cultured in different media for 7 days (p808, right column). This teaching reads on the P0 can be 7 days, which is in the range of the duration of 7 to 16 days, as recited in instant claim 40.
Regarding claim 46, following the discussion above, Clevers et al. do not teach seeding cells on an ECM-coated two-dimensional surface, as well as seeding the hepatocytes at a density of 200 cells/cm2 to 13,333 cells/cm2 at step P0, or seeding the hepatocytes at a density of 333 cells/cm2 to 13,333 cells/cm2 at step P1. However, Zhang et al. teach the cryopreserved primary human hepatocytes
were seeded in a collagen-I-coated dish at 2X104 cells/cm2. The medium was changed to HM 10 hours after seeding and every 2 days thereafter. On day 6 of the primary culture, cells were trypsinized and then seeded at 3X104 cells/cm2 in collagen-I-coated dishes (pe2, “Human hepatocyte culture” part). This teaching reads on seeding the hepatocytes at a density of 2X104 cells/cm2 at step P0, and seeding the hepatocytes at a density of 3X104 cells/cm2 at step P1, which are slightly higher than the density recited in instant claim. However, it is not inventive to find optimal workable ranges by routine experimentation. Generally, differences in concentration or temperature, or in this case, the cell seeding density during the culture period will not support the patentability of subject matter encompassed by the prior art unless there is evidence indicating such concentration or temperature or the cell seeding density is critical. "[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation." See Jn re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955).
Regarding claim 50, Clevers et al. teach the cell culture medium (for the primary hepatocytes) is supplemented with a purified, natural, semisynthetic and/or synthetic growth factor and does not comprise an undefined component such as fetal bovine serum or fetal calf serum (p24, L23-25). Clevers et al. teach various different serum replacement formulations are commercially available and can be used. When a serum replacement is used, it may be used at between about 1 % and about 30% by volume of the medium, according to conventional techniques (see p24, L23-27). Clevers et al. do not specifically point out the concentration of the serum replacement component is varied over the duration of the culturing step. However, an ordinary skill in the art can modify or optimize the concentration of the serum replacement based on the instruction of the commercially available serum replacement (i.e., keep the concentration within the range of 1% - 30%) during the culture period, and it is not inventive to find optimal workable ranges by routine experimentation. Generally, differences in concentration (i.e., herein the various concentration of serum replacement during the culture period) will not support the patentability of subject matter encompassed by the prior art unless there is evidence indicating such concentration is critical. "[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation." See Jn re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955).
Double Patenting
The nonstatutory double patenting rejection is based on a judicially created doctrine grounded in public policy (a policy reflected in the statute) so as to prevent the unjustified or improper timewise extension of the “right to exclude” granted by a patent and to prevent possible harassment by multiple assignees. A nonstatutory double patenting rejection is appropriate where the conflicting claims are not identical, but at least one examined application claim is not patentably distinct from the reference claim(s) because the examined application claim is either anticipated by, or would have been obvious over, the reference claim(s). See, e.g., In re Berg, 140 F.3d 1428, 46 USPQ2d 1226 (Fed. Cir. 1998); In re Goodman, 11 F.3d 1046, 29 USPQ2d 2010 (Fed. Cir. 1993); In re Longi, 759 F.2d 887, 225 USPQ 645 (Fed. Cir. 1985); In re Van Ornum, 686 F.2d 937, 214 USPQ 761 (CCPA 1982); In re Vogel, 422 F.2d 438, 164 USPQ 619 (CCPA 1970); In re Thorington, 418 F.2d 528, 163 USPQ 644 (CCPA 1969).
A timely filed terminal disclaimer in compliance with 37 CFR 1.321(c) or 1.321(d) may be used to overcome an actual or provisional rejection based on nonstatutory double patenting provided the reference application or patent either is shown to be commonly owned with the examined application, or claims an invention made as a result of activities undertaken within the scope of a joint research agreement. See MPEP § 717.02 for applications subject to examination under the first inventor to file provisions of the AIA as explained in MPEP § 2159. See MPEP § 2146 et seq. for applications not subject to examination under the first inventor to file provisions of the AIA . A terminal disclaimer must be signed in compliance with 37 CFR 1.321(b).
The filing of a terminal disclaimer by itself is not a complete reply to a nonstatutory double patenting (NSDP) rejection. A complete reply requires that the terminal disclaimer be accompanied by a reply requesting reconsideration of the prior Office action. Even where the NSDP rejection is provisional the reply must be complete. See MPEP § 804, subsection I.B.1. For a reply to a non-final Office action, see 37 CFR 1.111(a). For a reply to final Office action, see 37 CFR 1.113(c). A request for reconsideration while not provided for in 37 CFR 1.113(c) may be filed after final for consideration. See MPEP §§ 706.07(e) and 714.13.
The USPTO Internet website contains terminal disclaimer forms which may be used. Please visit www.uspto.gov/patent/patents-forms. The actual filing date of the application in which the form is filed determines what form (e.g., PTO/SB/25, PTO/SB/26, PTO/AIA /25, or PTO/AIA /26) should be used. A web-based eTerminal Disclaimer may be filled out completely online using web-screens. An eTerminal Disclaimer that meets all requirements is auto-processed and approved immediately upon submission. For more information about eTerminal Disclaimers, refer to www.uspto.gov/patents/apply/applying-online/eterminal-disclaimer.
Claims 1, 4, 7, 10, 16, 18, 21, 26, 39, 40, 46 and 50 are provisionally rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1, 4, 6, 8 and 10-15 of co-pending Application No. 19/684,193 (reference application). Although the claims at issue are not identical, they are not patentably distinct from each other because co-pending claims anticipate or renders obviousness to instant claims. This is a provisional nonstatutory double patenting rejection because the patentably indistinct claims have not in fact been patented.
Regarding claims 1, 4, 7, 10, 18 and 21, co-pending claims 1, 4 and 8 teach a method for culturing primary human hepatocytes, the method comprising the step of culturing one or more hepatocytes in contact with an extracellular matrix (ECM) in the presence of an expansion medium comprising a basal medium for human cells to which is added: Wnt3a, an R-spondin, a fibroblast growth factor (FGF),an epidermal growth factor (EGF), a hepatocyte growth factor (HGF), and a transforming growth factor-alpha (TGF-alpha), wherein the culturing step is performed on a two-dimensional surface coated with the ECM, wherein the hepatocytes are adherently attached to the surface during the culturing step, wherein the expansion medium comprises a TGFβ inhibitor, and wherein the ECM comprises a laminin.
Regarding claim 16, co-pending claim 6 teaches the expansion medium does not contain gastrin, a Rho kinase inhibitor, a Notch inhibitor, a Notch agonist, or a combination thereof.
Regarding claims 26 and 50, co-pending claim 10 teaches the expansion medium comprises a serum replacement component, and the concentration of the serum replacement component is varied over the duration of the culturing step.
Regarding claims 39 and 40, co-pending claims 11-13 teach the culturing step comprises expanding plated hepatocytes (step P0) and a first passage of expanded hepatocytes (step P1), and step P0 has a duration of 7 to 16 days, or wherein step P1 has a duration of 7 to 20 days.
Regarding claim 46, co-pending claims 14-15 teach the step P0 comprises seeding the hepatocytes at a density of 200 cells/cm2 to 13,333 cells/cm2, or step P1 comprises seeding the hepatocytes at a density of 333 cells/cm2 to 13,333 cells/cm2.
Claims 1, 4, 7, 10, 16, 18, 21, 26, 39, 40, 46, 50, 64, 83, 84 and 89 are provisionally rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1, 4, 6, 8 and 10-15 of copending Application No. 19/684,193 in view of Clevers et al. (WO 2020/109324 A1, published 06/04/2020, cited in IDS). This is a provisional nonstatutory double patenting rejection.
Regarding claims 64, 83, 84 and 89, co-pending claims do not teach maturing the hepatocytes as recited in instant claims. However, this was disclosed by Clevers et al.. Clevers et al. teach a differentiation medium for maturation of fetal hepatocytes (p13, L7-8). The differentiation medium comprises the hepatocyte culture medium of the invention and at least one of dexamethasone and oncostatin M (p12, L33-35). Clevers et al. teach differentiating the cells of Fetal-orgs and/or single cells derived therefrom is performed by culturing the cells in a differentiation medium (p12, L27-28), indicates that the maturation step begins immediately following the hepatocyte expansion (i.e., change the medium from expansion medium to differentiation medium).
It would have been prima facie obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify instant claims’ method of culturing primary human hepatocytes, and further use a differentiation medium for maturation of the cultured hepatocytes as taught by Clevers et al.. The skilled artisan would have been motivated to use a differentiation medium for maturation of hepatocytes, since Clevers et al. teach mature hepatocyte is beneficial for cell transplant since transplantability generally correlates with hepatocyte maturity (p47, L31). There would be a reasonable expectation of success of using a differentiation medium for maturation of the cultured hepatocytes since Clevers et al. teach the recipe of the differentiation medium (see i.e., p12, L33-35; p3, L24-31; and p24, L2-3).
Claims 1, 4, 7, 10, 15, 16, 18, 21, 26, 39, 40 and 50 are provisionally rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1, 4, 6, 8, 11, 12, 14 and 15 of co-pending Application No. 19/702,355 (reference application). Although the claims at issue are not identical, they are not patentably distinct from each other because co-pending claims anticipate or renders obviousness to instant claims. This is a provisional nonstatutory double patenting rejection because the patentably indistinct claims have not in fact been patented.
Regarding claims 1, 4, 7, 10, 18 and 21, co-pending claims 1 and 6 teach a method of expanding hepatocytes, the method comprising culturing one or more hepatocytes on a cell culture surface in the presence of a cell culture medium comprising a basal cell culture medium for human cells to which is added a concentration of: a fibroblast growth factor (FGF), an epidermal growth factor (EGF), a hepatocyte growth factor (HGF), an R-spondin, and a transforming growth factor-beta (TGF-beta) inhibitor, wherein one or more of FGF7, Wnt3a, and transforming growth factor-alpha (TGF-alpha) are not added to the cell culture medium, wherein the surface of the cell culture vessel is coated with an extracellular matrix (ECM), and wherein the hepatocytes are cultured in a two-dimensional culture system, wherein the ECM comprises a laminin.
Regarding claim 15, co-pending claim 8 teaches N-acetyl cysteine is added to the cell culture medium.
Regarding claim 16, co-pending claims 11 and 12 teaches one or more of gastrin, arachidonic acid, and prostaglandin E2 are not added to the cell culture medium.
Regarding claims 26 and 50, co-pending claim 4 teaches a serum or a serum replacement component is added to the cell culture medium at a volumetric concentration of 1% to 6% and is increased to a volumetric concentration of 7% to 15% when the hepatocytes reach 30% to 70% confluency.
Regarding claims 39 and 40, co-pending claims 14 and 15 teach passaging the hepatocytes, wherein each passage is 5 to 25 days, indicates that the culture method comprises P0 which can be 7 to 16 days and P1 which can be 7-20 days.
Claims 1, 4, 7, 10, 15, 16, 18, 21, 26, 39, 40, 50, 64, 83, 84 and 89 are provisionally rejected on the ground of nonstatutory double patenting as being unpatentable over claim 1, 4, 6, 8, 11, 12, 14 and 15 of copending Application No. 19/702,355 in view of Clevers et al. (WO 2020/109324 A1, published 06/04/2020, cited in IDS). This is a provisional nonstatutory double patenting rejection.
Regarding claims 64, 83, 84 and 89, co-pending claims do not teach maturing the hepatocytes as recited in instant claims. However, this was disclosed by Clevers et al.. Clevers et al. teach a differentiation medium for maturation of fetal hepatocytes (p13, L7-8). The differentiation medium comprises the hepatocyte culture medium of the invention and at least one of dexamethasone and oncostatin M (p12, L33-35). Clevers et al. teach differentiating the cells of Fetal-orgs and/or single cells derived therefrom is performed by culturing the cells in a differentiation medium (p12, L27-28), indicates that the maturation step begins immediately following the hepatocyte expansion (i.e., change the medium from expansion medium to differentiation medium).
It would have been prima facie obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify instant claims’ method of culturing primary human hepatocytes, and further use a differentiation medium for maturation of the cultured hepatocytes as taught by Clevers et al.. The skilled artisan would have been motivated to use a differentiation medium for maturation of hepatocytes, since Clevers et al. teach mature hepatocyte is beneficial for cell transplant since transplantability generally correlates with hepatocyte maturity (p47, L31). There would be a reasonable expectation of success of using a differentiation medium for maturation of the cultured hepatocytes since Clevers et al. teach the recipe of the differentiation medium (see i.e., p12, L33-35; p3, L24-31; and p24, L2-3).
Claims 1, 4, 7, 10, 15, 16, 18, 21, 26, 39, 40, 46 and 50 are provisionally rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1, 6, 10-13 and 15-17 of co-pending Application No. 19/684,582 (reference application). Although the claims at issue are not identical, they are not patentably distinct from each other because co-pending claims anticipate or renders obviousness to instant claims. This is a provisional nonstatutory double patenting rejection because the patentably indistinct claims have not in fact been patented.
Regarding claims 1, 4, 7, 10, 18 and 21, co-pending claims 1 and 6 teach a method of culturing hepatocytes, the method comprising culturing one or more hepatocytes on a cell culture surface in the presence of a cell culture medium comprising a basal cell culture medium for human cells to which is added a concentration of: a fibroblast growth factor (FGF),an epidermal growth factor (EGF), a hepatocyte growth factor (HGF),an R-spondin, a transforming growth factor-beta (TGF-beta) inhibitor, a Yes-associated protein (YAP) activator, and a signal transducer and activator of transcription 3 (STAT3) activator, wherein one or more of FGF7, Wnt3a, and transforming growth factor-alpha (TGF-alpha) are not added to the cell culture medium, wherein the surface of the cell culture vessel is coated with an extracellular matrix (ECM), and wherein the hepatocytes are cultured in a two-dimensional culture system, wherein the ECM comprises a laminin.
Regarding claim 15, co-pending claim 10 teaches N-acetyl cysteine is added to the cell culture medium.
Regarding claim 16, co-pending claims 11 teaches one or more of gastrin, arachidonic acid, and prostaglandin E2 are not added to the cell culture medium.
Regarding claims 26 and 50, co-pending claims 12 and 13 teach adding a serum replacement component to the basal cell culture medium, wherein the serum or serum replacement component is added to the cell culture medium at a volumetric concentration of 1% to 5% upon plating the hepatocytes and is increased in the cell culture medium to a volumetric concentration of 7% to 15% over the course of culturing.
Regarding claims 39, 40 and 46, co-pending claims 15-17 teach step P0 and P1, as well as the cell density, renders obvious to instant claims.
Claims 1, 4, 7, 10, 15, 16, 18, 21, 26, 39, 40, 46, 50, 64, 83, 84 and 89 are provisionally rejected on the ground of nonstatutory double patenting as being unpatentable over claim 1, 6, 10-13 and 15-17 of copending Application No. 19/684,582 in view of Clevers et al. (WO 2020/109324 A1, published 06/04/2020, cited in IDS). This is a provisional nonstatutory double patenting rejection.
Regarding claims 64, 83, 84 and 89, co-pending claims do not teach maturing the hepatocytes as recited in instant claims. However, this was disclosed by Clevers et al.. Clevers et al. teach a differentiation medium for maturation of fetal hepatocytes (p13, L7-8). The differentiation medium comprises the hepatocyte culture medium of the invention and at least one of dexamethasone and oncostatin M (p12, L33-35). Clevers et al. teach differentiating the cells of Fetal-orgs and/or single cells derived therefrom is performed by culturing the cells in a differentiation medium (p12, L27-28), indicates that the maturation step begins immediately following the hepatocyte expansion (i.e., change the medium from expansion medium to differentiation medium).
It would have been prima facie obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify instant claims’ method of culturing primary human hepatocytes, and further use a differentiation medium for maturation of the cultured hepatocytes as taught by Clevers et al.. The skilled artisan would have been motivated to use a differentiation medium for maturation of hepatocytes, since Clevers et al. teach mature hepatocyte is beneficial for cell transplant since transplantability generally correlates with hepatocyte maturity (p47, L31). There would be a reasonable expectation of success of using a differentiation medium for maturation of the cultured hepatocytes since Clevers et al. teach the recipe of the differentiation medium (see i.e., p12, L33-35; p3, L24-31; and p24, L2-3).
Claims 1, 4, 7, 10, 15, 16, 18, 21, 26, 39, 40 and 50 are provisionally rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1, 4, 6, 8, 13 and 20-21 of co-pending Application No. 19/060,439 (reference application). Although the claims at issue are not identical, they are not patentably distinct from each other because co-pending claims anticipate or renders obviousness to instant claims. This is a provisional nonstatutory double patenting rejection because the patentably indistinct claims have not in fact been patented.
Regarding claims 1, 4, 7, 10, 18 and 21, co-pending claims 1 and 6 teach a method of expanding hepatocytes comprising culturing one or more hepatocytes on a cell culture surface in the presence of a cell culture medium comprising a basal cell culture medium for human cells to which is added a concentration of: a fibroblast growth factor (FGF), an epidermal growth factor (EGF), a hepatocyte growth factor (HGF), an R-spondin, and a transforming growth factor-beta (TGF-beta) inhibitor, wherein one or more of FGF7, Wnt3a, and transforming growth factor-alpha (TGF-alpha) are not added to the cell culture medium, wherein the surface of the cell culture vessel is coated with an extracellular matrix (ECM), and wherein the hepatocytes are cultured in a two-dimensional culture system, wherein the ECM comprises a laminin.
Regarding claim 15, co-pending claim 8 teaches N-acetyl cysteine is added to the cell culture medium.
Regarding claim 16, co-pending claim 13 teaches one or more of gastrin, arachidonic acid, and prostaglandin E2 are not added to the cell culture medium.
Regarding claims 26 and 50, co-pending claim 4 teaches a serum or a serum replacement component is added to the cell culture medium at a volumetric concentration of 1% to 6% and is increased to a volumetric concentration of 7% to 15% when the hepatocytes reach 30% to 70% confluency.
Regarding claims 39 and 40, co-pending claims 20-21 teach passaging the hepatocytes, wherein each passage is 5 to 25 days renders obvious to instant claims.
Claims 1, 4, 7, 10, 15, 16, 18, 21, 26, 39, 40, 50, 64, 83, 84 and 89 are provisionally rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1, 4, 6, 8, 13 and 20-21 of copending Application No. 19/060,439 in view of Clevers et al. (WO 2020/109324 A1, published 06/04/2020). This is a provisional nonstatutory double patenting rejection.
Regarding claims 64, 83, 84 and 89, co-pending claims do not teach maturing the hepatocytes as recited in instant claims. However, this was disclosed by Clevers et al.. Clevers et al. teach a differentiation medium for maturation of fetal hepatocytes (p13, L7-8). The differentiation medium comprises the hepatocyte culture medium of the invention and at least one of dexamethasone and oncostatin M (p12, L33-35). Clevers et al. teach differentiating the cells of Fetal-orgs and/or single cells derived therefrom is performed by culturing the cells in a differentiation medium (p12, L27-28), indicates that the maturation step begins immediately following the hepatocyte expansion (i.e., change the medium from expansion medium to differentiation medium).
It would have been prima facie obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify instant claims’ method of culturing primary human hepatocytes, and further use a differentiation medium for maturation of the cultured hepatocytes as taught by Clevers et al.. The skilled artisan would have been motivated to use a differentiation medium for maturation of hepatocytes, since Clevers et al. teach mature hepatocyte is beneficial for cell transplant since transplantability generally correlates with hepatocyte maturity (p47, L31). There would be a reasonable expectation of success of using a differentiation medium for maturation of the cultured hepatocytes since Clevers et al. teach the recipe of the differentiation medium (see i.e., p12, L33-35; p3, L24-31; and p24, L2-3).
Conclusion
No claims are allowed.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to QINHUA GU whose telephone number is (703)756-1176. The examiner can normally be reached M-F: 9:00 - 5:00.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Christopher Babic can be reached at (571)272-8507. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/Q.G./Examiner, Art Unit 1633
/FEREYDOUN G SAJJADI/Supervisory Patent Examiner, Art Unit 1699
Prosecution Insights