Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
DETAILED ACTION
Priority
This application is a continuation of U.S. Patent Application No. 17/046,871, filed October 12, 2020, which is a National Stage Application of International Application No. PCT/US2019/028216, filed April 19, 2019, which claims priority to U.S. Provisional Application No. 62/661,928 filed April 24, 2018, that is hereby acknowledged by the Examiner.
Status of the Claims
The amendment dated 09/26/2024 is acknowledged. Claims 1-11, 15-16, 20-22, 24-26 and 28 are pending under examination.
Information Disclosure Statement
The information disclosure statement (IDS) submitted on 08/23/2024 is in compliance with the provisions of 37 CFR 1.97. Accordingly, the information disclosure statement(s) is/are being considered by the Examiner.
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.
Claim 11 is rejected under 35 U.S.C. 112(b), as being indefinite for failing to particularly point out and distinctly claim the subject matter which applicant regards as the invention.
Claim 11 recites “Shield 1”, which is a stabilizing agent such as Shield-1, commercially available from Cheminpharma LLC (Farmington, CT) or Clontech Laboratories, Inc. (Mountain View, CA). Where a trademark or trade name is used in a claim as a limitation to identify or describe a particular material or product, the claim does not comply with the requirements of 35 U.S.C. 112, second paragraph. See Ex parte Simpson, 218 USPQ 1020 (Bd. App. 1982) (see para. [47] of Applicant’s specification). The claim scope is uncertain since the trademark or trade name cannot be used properly to identify any particular material or product. A trademark or trade name is used to identify a source of goods, and not the goods themselves. Thus, a trademark or trade name does not identify or describe the goods associated with the trademark or trade name. In the present case, the trademark/trade name is used to identify/describe a reactive compound, wherein the reactive compound can be from either a redox active compound, a radical building compound, or a stabilizing compound and, accordingly, the identification/description is indefinite.
Claim Rejections - 35 USC § 102
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.
Claim 28 is rejected under 35 U.S.C. 102(a)(1) as being anticipated by Federspiel et al. (US PGPUB 2010/0143889, IDS of record dated 08/23/2024).
The claim is directed to a process for sterilizing a large virus comprising:
applying unpurified material comprising said virus onto a 0.2 um membrane made of PVDF or cellulose acetate; and b) collecting purified virus.
Regarding claim 28, Federspiel discloses a process for sterilizing a large virus (Abstract, methods and materials for obtaining large Volume, high titer, high purity preparations of Rhabdoviridae viruses (e.g., VSV) with low or non-existent levels of contaminants are provided), comprising: a) applying unpurified material comprising said virus onto a 0.2 μm membrane made of PVDF or cellulose acetate; and b) collecting purified virus (Para. [0031], a Supernatant containing Rhabdoviridae virus can be filtered using a series of filters of sequentially decreasing pore size (e.g., the first filter may have a pore size between 40-8 microns. followed by a 5-3 micron filter, followed by a 1.5-0.2 micron filter); Para. [0033). In some cases, a final filtration step can be performed using a standard filter (e.g., 0.2 or 0.45 or 1.2 micron filter). Any filter material can be used (e.g., polyethersulfone, PVDF, nylon, polypropylene). Once this final filtration step is completed, the sample can be aseptically Vialed for use in clinical Settings).
Therefore, the cited prior art anticipates the claimed invention.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103(a) which forms the basis for all obviousness rejections set forth in this Office action:
(a) A patent may not be obtained though the invention is not identically disclosed or described as set forth in section 102 of this title, if the differences between the subject matter sought to be patented and the prior art are such that the subject matter as a whole would have been obvious at the time the invention was made to a person having ordinary skill in the art to which said subject matter pertains. Patentability shall not be negatived 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.
This application currently names joint inventors. In considering patentability of the claims under 35 U.S.C. 103(a), the examiner presumes that the subject matter of the various claims was commonly owned at the time any inventions covered therein were made absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and invention dates of each claim that was not commonly owned at the time a later invention was made in order for the examiner to consider the applicability of 35 U.S.C. 103(c) and potential 35 U.S.C. 102(e), (f) or (g) prior art under 35 U.S.C. 103(a).
Claims 1-2, 6-8, 10 and 15-16 are rejected under 35 U.S.C. 103(a) as being unpatentable over Anderson et al. (US PGPUB 2017/0349634, IDS of record dated 08/23/2024) in view of Zhou (US PGPUB 2007/0167612, IDS of record dated 08/23/2024).
The claims are directed to a method of purifying human cytomegalovirus (HCMV) from a cell culture medium, the method comprising: a) contacting the cell culture medium comprising HCMV to an anion exchange chromatography medium under conditions that allow the HCMV to bind to the anion exchange chromatography medium; b) eluting the HCMV from the anion exchange chromatography medium to obtain an eluate; c) contacting the eluate with a polishing chromatography medium; and d) collecting the HCMV from the polishing chromatography medium to obtain purified HCMV.
Regarding claim 1, Anderson discloses a method of purifying human cytomegalovirus (HCMV) from a cell culture medium (Para. [0005]. provided VLPs contain one or more epitopes from viral structural proteins (e.g., pp65) which are antigens that play a role in induction of cellular immune responses (e.g., T-cell response). In some embodiments, utilized viral structural proteins (e.g., pp65) both stimulate formation of T-helper cells and also induce cytotoxic T lymphocytes (CTL) against HCMV; Para. [0006), In some embodiments, the present invention provides variants of viral envelope glycoproteins (e.g., gB and/or gH); Para. {0167). VLPs were produced and purified as follows. CHO cells were transfected .... The cells were cultured for 72 hours), the method comprising: a) contacting the cell culture medium comprising HCMV to an anion exchange chromatography medium under conditions that allow the HCMV to bind to the anion exchange chromatography medium (Para. [0167), The diafiltered material was loaded onto an anion exchange chromatography column (AEX); Para. (0169], AEX column chromatography was used to reduce DNA content.. .. Loading was performed at 3.2 mUmin, after which the column was washed with 5 column volumes of equilibration buffer, or until the base line was observed; Para. [0170), As shown in FIG. 11, intact gB-G monovalent VLPs are present after TFF (FIG. 11A) and AEX purification (FIG. 11 Bl), ; b) eluting the HCMV from the anion exchange chromatography medium to obtain an eluate (Para. [0169), The column was then stripped by 5 column volumes of stripping buffer (20 mM Histidine+1000 mM NaCl, pH 5.5) and the peak was collected. This was followed by 5 column volumes of another stripping buffer (20 mM Histidine+2000 mM NaCl, pH 5.5) to remove any strongly bound proteins and nucleic acids and the peak was collected).
Anderson fails to explicitly disclose c) contacting the eluate with a polishing chromatography medium; and d) collecting the HCMV from the polishing chromatography medium to obtain purified HCMV.
Zhou, however, teaches multi-step biomolecule purifications where an eluate from a first chromatography step is followed by a polishing step (Para. (0004), After a target molecule has been partially purified by an initial column-chromatography step and collected in an eluate pool, the partially purified target molecule is often subjected to further purification steps, generally referred to as "polishing steps."). where the target biomolecule is collected from the polishing chromatography medium to obtain purified target biomolecule (Para. (0026), In many embodiments of the present invention, a flow-through ("FT") O-membrane ("QM") polishing step is employed, in which an antibody-containing solution is passed through the multi-layer O-membrane cell at relatively high flow rates, with passage of undesirable, relatively large host-cell proteins, DNA, RNA, intact viruses, and endotoxins restricted by the Q membrane, while smaller antibody molecules readily pass through the Q-membrane cell for downstream collection).
Accordingly, it would have been obvious to one of ordinary skill in the art at the time of the invention to modify Anderson with the teaching of Zhou for the purpose of providing a rapid second purification step for a target biomolecule, as taught by Zhou (Para. [0009]. One of ordinary skill in the art would have been motivated to do so with a reasonable expectation of success as various embodiments of the present invention are directed to multi-step target-molecule purification systems that include chromatography-based and/or membrane-filtration-based polishing steps. Described embodiments of the present invention may be directed to separating target proteins, including recombinant monoclonal antibodies, from complex solutions that include host-cell proteins, viral particles, and other impurities; Para. [0025], using a Q membrane may eliminate other steps that are typically required .... may decrease the processing time of the polishing steps by an entire day).
Regarding Claim 2, modified Anderson discloses the method of claim 1. Anderson fails to explicitly disclose wherein the polishing chromatography medium is selected from a mixed-mode chromatography resin and a cationic exchange chromatography medium. Zhou teaches a polishing chromatography medium may be a cationic exchange chromatography medium (Abstract, a target-protein-containing eluate having a high residual salt concentration is collected from a first chromatography column prepared
with an affinity-chromatography resin, loaded onto a second chromatography column prepared with a cation-exchange resin, and eluted; Para. [0016), In various embodiments of the present invention, anion-exchange processes and cation-exchange processes may be used in one or more polishing steps following a protein-A-affinity-chromatography-based purification step).
It would have been obvious to one of ordinary skill in the art at the time of the invention to modify Anderson with the teaching of Zhou. One of ordinary skill in the art would have been motivated to do so with a reasonable expectation of success for the purpose of providing a rapid second purification step for a target biomolecule, as taught by Zhou (Para. [0009], Various embodiments of the present invention are directed to multi-step target-molecule purification systems that include chromatography-based and/or membrane-filtration-based polishing steps. Described embodiments of the present invention may be directed to separating target proteins, including recombinant monoclonal antibodies, from complex solutions that include host-cell proteins, viral particles, and other impurities; Para. (0025), using a Q mem9rane may eliminate other steps that are typically required .... may decrease the processing time
of the polishing steps by an entire day).
Regarding Claim 6, modified Anderson discloses the method of claim 2. Anderson further discloses wherein the chromatography medium is a cationic exchange chromatography medium, the HCMV binds the cation exchange chromatography medium, and the HCMV is eluted from the cationic exchange chromatography medium (Para. [0113], VLPs may be purified according to known techniques, such as
centrifugation, gradients, sucrose-gradient ultracentrifugation, tangential flow filtration and chromatography (e.g., ion exchange (anion and cation), affinity and sizing column chromatography), or differential solubility, among others).
Anderson fails to explicitly disclose a cation exchange polishing step.
Zhou, however, teaches a cation exchange polishing step where a target molecule binds the cation exchange chromatography medium, and the target is eluted from the cationic exchange chromatography medium (Abstract, a target-protein-containing eluate having a high residual salt concentration is collected from a first chromatography column prepared with an affinity-chromatography resin, loaded onto a second chromatography column prepared with a cation-exchange resin, and eluted from the second cation-exchange column. using a buffer in which a time-dependent pH gradient is established; Para. [0004). After a target molecule has been partially purified by an initial column-chromatography step and collected in an eluate pool, the partially purified target molecule is often subjected to further purification steps, generally referred to as "polishing steps.").
It would have been obvious to one of ordinary skill in the art at the time of the invention to modify Anderson with the teaching of Zhou. One of ordinary skill in the art would have been motivated to do so with a reasonable expectation of success for the purpose of providing a rapid second purification step for a target biomolecule, as taught by Zhou (Para. [0009), Various embodiments of the present invention are directed to multi-step target-molecule purification systems that include chromatography-based
and/or membrane-filtration-based polishing steps. Described embodiments of the present invention may be directed to separating target proteins, including recombinant monoclonal antibodies, from complex solutions that include host-cell proteins, viral particles, and other impurities; Para. [0025), using a Q membrane may eliminate other steps that are typically required .... may decrease the processing time
of the polishing steps by an entire day).
Regarding Claim 7, modified Anderson discloses the method of claim 1. Anderson further discloses further comprising tangential flow filtration of the eluate from step b), the purified HCMV from step d), or both (Para. [0113], VLPs may be purified according to known techniques, such as centrifugation, gradients, sucrose-gradient ultracentrifugation, tangential flow filtration and chromatography; Para. [0167), The cells were cultured for 72 hours, and then the cultures were centrifuged at 4000 rpm for 20 minutes, using rotor JS-4.2A by Beckman Coulter, in 1 L bottles. The supernatant was filtered through 0.8/0.45 nm filter (AcroPak 500 Capsule, Pall). The filtered
supernatant was then concentrated by Tangential Flow Filtration (TFF) and diafiltered against histidine containing buffer).
Regarding Claim 8, modified Anderson discloses the method of claim 1. Anderson further discloses wherein the HCMV is a recombinant genetically modified HCMV (Para. [0006], In some embodiments, the present invention provides variants of viral envelope glycoproteins (e.g., gB and/or gH); Para. [0081], In some embodiments, an envelope polypeptide from HCMV includes a transmembrane and cytoplasmic domain that is not found in nature in the HCMV protein. For example, in some embodiments, an envelope polypeptide from HCMV includes a transmembrane and cytoplasmic domain from another HCMV protein (e.g., gB or gH); Para. [0109], Provided VLPs in accordance with the present invention may be prepared according to general methodologies known to the skilled person. For example, various nucleic acid molecules, genomes or reconstituted vectors or plasmids may be prepared using sequences of known viruses .... Various synthetic or artificial sequences may also be produced from computer analysis or through (high throughput) screening of libraries. Recombinant expression of the polypeptides for VLPs .... the vector for production of the polypeptide may be produced by recombinant DNA technology).
Regarding Claim 10, modified Anderson discloses the method of claim 1. Anderson further discloses wherein the cell culture medium comprises one or more contaminants selected from proteins and nucleic acids. (Para. [0167], The diafiltered material was loaded onto an anion exchange chromatography column (AEX); Para. [0169], AEX column chromatography was used to reduce DNA content).
Regarding Claim 15, modified Anderson discloses the method of claim 1. Anderson further discloses wherein said eluting in step b) is by a salt selected from sodium chloride, potassium chloride, ammonium chloride, and sodium sulfate, each at a concentration of about 0.5-2 M (Para. (0169), The column was then stripped by 5 column volumes of stripping buffer (20 mM Histidine+1000 mM NaCl, pH 5.5) and the peak was collected. This was followed by 5 column volumes of another stripping buffer (20 mM Histidine+2000 mM NaCl, pH 5.5) to remove any strongly bound proteins and nucleic acids).
Regarding Claim 16, modified Anderson discloses the method of claim 1. Anderson further discloses wherein said eluting in step b) is by an amino acid selected from arginine and histidine (Para. [0169), The column was then stripped by 5 column volumes of stripping buffer (20 mM Histidine+1000 mM NaCl, pH 5.5) and the peak was collected. This was followed by 5 column volumes of another stripping buffer (20 mM Histidine+2000 mM NaCl, pH 5.5) to remove any strongly bound proteins and nucleic acids), each at a concentration of about 0.25 - 1 M.
Anderson fails to explicitly disclose histidine at a concentration of about 0.25 - 1 M.
It would have been obvious to one of ordinary skill in the art at the time the invention was made to use 0.25 - 1 M histidine, since where the general conditions of the claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art. The motivation for doing so with a reasonable expectation of success would be to use a histidine concentration that elutes the virus, as taught by Anderson (Para. [0169); the column was then stripped by 5 column volumes of stripping buffer (20 mM Histidine+1000 mM NaCl, pH 5.5) and the peak was collected. This was followed by 5 column volumes of another stripping buffer (20 mM Histidine+2000 mM NaCl, pH 5.5) to remove any strongly bound proteins and nucleic acids).
Therefore, the claimed invention would have been prima facie obvious to one of ordinary skill in the art before the effective filing date of the claimed invention.
Claims 3-5 are rejected under 35 U.S.C. 103(a) as being unpatentable over Anderson et al. (US PGPUB 2017/0349634, IDS of record dated 08/23/2024) in view of Zhou (US PGPUB 2007/0167612, IDS of record dated 08/23/2024) and further in view of "Data file 28-9983-07 AA: Multimodal chromatography: Capto Core 700" (hereinafter GE Healthcare, IDS of record dated 08/23/2024). The teachings of Anderson and Zhou are outlined above and incorporated herein.
Regarding claim 3, modified Anderson discloses the method of claim 2. Anderson fails to explicitly disclose wherein the polishing chromatography medium is a mixed-mode chromatography resin and the HCMV flows through the mixed-mode chromatography resin. GE Healthcare teaches a mixed mode polishing resin for whole virus purification (Pg. 1, Col. 1, Para. 1, Capto Core 700 is designed for intermediate purification and polishing of viruses and other large biomolecules. The novel core bead technology and multimodal, octylamine ligand give Capto Core 700 dual-functionality, size separation, and binding chromatography in one chromatography medium (resin)), with a MW cutoff of 700Kd, such that HCMV flows through the resin (Pg. 1, Col. 1, Para. 2, Core bead technology with ligand-activated core and inactive shell allows efficient capture of contaminants while target molecules are collected in the flowthrough; Table 1. Characteristics of Capto Core 700, Molecular weight cutoff Mr 700 000).
It would have been obvious to one of ordinary skill in the art at the time of the invention to modify Anderson with the teaching of GE Healthcare. One of ordinary skill in the art would have been motivated to do so with a reasonable expectation of success for the purpose of using a resin with particular advantage over gel-filtration as taught by GE Healthcare (Pg. 1, Col. 1, Para. 1, These features make Capto Core 700 an excellent alternative to gel filtration (size-exclusion chromatography) media that are typically employed in the final stages of virus purification in vaccine manufacture. Capto Core 700 offers a range of performance advantages over gel filtration (GF), which is often regarded as a productivity bottleneck in the polishing process due to low flow rates and limited sample loads).
Regarding Claim 4, modified Anderson discloses the method of claim 2. Anderson fails to explicitly disclose wherein the mixed-mode chromatography resin has size exclusion properties and the HCMV is excluded from the mixed-mode chromatography resin. GE Healthcare teaches a mixed mode, size-exclusion polishing resin for whole virus purification (Pg. 1, Col. 1, Para. 1, Capto Core 700 is designed for intermediate purification and polishing of viruses and other large biomolecules. The novel core bead technology and multimodal, octylamine ligand give Capto Core 700 dual-functionality, size separation, and binding chromatography in one chromatography medium (resin)), with a MW cutoff of 700Kd, such that HCMV flows through the resin (Pg. 1, Col. 1, Para. 2, Core bead technology with ligand-activated core and inactive shell allows efficient capture of contaminants while target molecules are collected in the flowthrough; Table 1. Characteristics of Capto Core 700, Molecular weight cutoff Mr 700 000).
It would have been obvious to one of ordinary skill in the art at the time of the invention to modify Anderson with the teaching of GE Healthcare. One of ordinary skill in the art would have been motivated to do so with a reasonable expectation of success for the purpose of using a resin with particular advantage over gel-filtration as taught by GE Healthcare (Pg. 1, Col. 1, Para. 1, These features make Capto Core 700 an excellent alternative to gel filtration (size-exclusion chromatography) media that are typically employed in the final stages of virus purification in vaccine manufacture. Capto Core 700 offers a range of performance advantages over gel filtration (GF), which is often regarded as a productivity bottleneck in the polishing process due to low flow rates and limited sample loads).
Regarding Claim 5, modified Anderson discloses the method of claim 4. Anderson fails to explicitly disclose wherein the mixed-mode chromatography resin includes a hydrophobic anion exchange chromatography ligand and a molecular weight exclusion of about 700 kDa. GE Healthcare teaches a mixed mode, size-exclusion/hydrophobic anion exchange polishing resin for whole virus purification (Pg. 1, Col. 1, Para. 1, Capto Core 700 is designed for intermediate purification and polishing of viruses and other large biomolecules. The novel core bead technology and multimodal, octylamine ligand (hydrophobic anion exchange) give Capto Core 700 dual-functionality, size separation, and binding chromatography in one chromatography medium (resin); Pg. 1, Col. 1, Para. 4, The core of each bead is
functionalized with ligands that are both hydrophobic and positively charged, resulting in a highly efficient multimodal binding of various contaminants), with a MW cutoff of 700Kd, such that HCMV flows through the resin (Pg. 1, Col. 1, Para. 2, Core bead technology with ligand-activated core and inactive shell allows efficient capture of contaminants while target molecules are collected in the flowthrough; Table 1. Characteristics of Capto Core 700, Molecular weight cutoff Mr 700 000).
It would have been obvious to one of ordinary skill in the art at the time of the invention to modify Anderson with the teaching of GE Healthcare. One of ordinary skill in the art would have been motivated to do so with a reasonable expectation of success for the purpose of using a resin with particular advantage over gel-filtration as taught by GE Healthcare (Pg. 1, Col. 1, Para. 1, These features make Capto Core 700 an excellent alternative to gel filtration (size-exclusion chromatography) media that are typically employed in the final stages of virus purification in vaccine manufacture. Capto Core 700 offers a range of performance advantages over gel filtration (GF). which is often regarded as a productivity bottleneck in the polishing process due to low flow rates and limited sample loads).
Therefore, the claimed invention would have been prima facie obvious to one of ordinary skill in the art before the effective filing date of the claimed invention.
Claim 9 is rejected under 35 U.S.C. 103(a) as being unpatentable over Anderson et al. (US PGPUB 2017/0349634, IDS of record dated 08/23/2024) in view of Zhou (US PGPUB 2007/0167612, IDS of record dated 08/23/2024) and further in view of and Merck Sharp & Dohme Corp. (US PGPUB 2014/0220062, hereinafter Merck, IDS of record dated 08/23/2024). The teachings of Anderson and Zhou are outlined above and incorporated herein.
Regarding Claim 9, modified Anderson discloses the method of claim 8. Anderson fails to explicitly disclose wherein the recombinant genetically modified HCMV has a genomic sequence of SEQ ID NO: 1.
Merck teaches a recombinant genetically modified HCMV comprising a genomic sequence of SEQ ID NO: 1 (Para. [0004), The present invention is directed to conditional replication defective CMV (rdCMV) and the use of rdCMV in compositions and methods of treating and/or decreasing the likelihood of an infection by CMV or pathology associated with such an infection in a patient. The rdCMV described herein comprises a nucleic acid encoding one or more fusion proteins that comprise an essential protein fused to a destabilizing protein .... replication is reduced, and preferably prevented, when administered to a patient (in the absence of the stabilizing agent); Para. [0049), The genome of the rdCMV with the destabilized IE1/2 and Ul51 is shown in SEQ ID NO:14 (100% identical to SEQ ID NO: 1 of the instant application)).
It would have been obvious to one of ordinary skill in the art at the time of the invention to modify Anderson with the teaching of Merck. One of ordinary skill in the art would have been motivated to do so with a reasonable expectation of success for the purpose of providing a replication deficient hCMV as taught by Merck.
Therefore, the claimed invention would have been prima facie obvious to one of ordinary skill in the art before the effective filing date of the claimed invention.
Claim 11 is rejected under 35 U.S.C. 103(a) as being unpatentable over Anderson et al. (US PGPUB 2017/0349634, IDS of record dated 08/23/2024) in view of Zhou (US PGPUB 2007/0167612, IDS of record dated 08/23/2024) and further in view of Merck Sharp & Dohme Corp. (US PGPUB 2014/0220062, hereinafter Merck, IDS of record dated 08/23/2024) and "Data file 28-9983-07 AA: Multimodal chromatography: Capto Core 700" (hereinafter GE Healthcare, IDS of record dated 08/23/2024).
Regarding Claim 11, modified Anderson discloses the method of claim 1. Anderson further discloses wherein the cell culture medium comprises host cell proteins, and host cell DNA (Para. (0167], The cells were cultured for 72 hours, and then the cultures were centrifuged at 4000 rpm for 20 minutes. using rotor JS-4.2A by Beckman Coulter, in 1 L bottles. The supernatant was filtered through 0.8/0.45 nm filter (AcroPak 500 Capsule, Pall). The filtered supernatant was then concentrated by Tangential Flow Filtration (TFF) and diafiltered against histidine-containing buffer; Para. [0169], AEX column chromatography was used to reduce DNA content....This was followed by 5 column volumes of another stripping buffer (20 mM Histidine+2000 mM NaCl, pH 5.5) to remove any strongly bound proteins and nucleic acids).
Anderson fails to explicitly disclose serum proteins, Shield 1, or exogenous endonuclease. GE Healthcare teaches removal of host cell proteins (HCP), serum proteins. host cell DNA, and exogenous endonuclease from culture medium comprising whole virus (Pg. 3, Col. 1, Paras. 1-2, Effective removal of HCP and DNA, Most HCP are negatively charged above pH 7. The ligands of Capto Core 700 are positively charged below a pKa of 10.6, and a pH of 7 to 9 is therefore recommended to ensure good binding of HCP. DNA is negatively charged over a wider pH range and the efficiency of the DNA removal is thus less dependent on pH. It is, however, recommended that DNA/RNA levels are reduced prior to the Capto Core 700 purification step, for example, by use of an anion exchange step or by treatment with Benzonase™ endonuclease. Degradation of DNA using Benzonase yields small oligonucleotide fragments that enter the core of the beads where these bind to the internal ligands. Benzonase will also enter the core and bind, and will thus be removed from the virus flowthrough fraction; Molecular weight cutoff, To investigate the molecular weight cutoff, the dynamic binding capacity of Capto Core 700 was determined for a range of proteins of different sizes. The proteins investigated were ovalbumin (Mr 45 000), apoferritin (Mr 475 000), thyroglobulin (Mr 660 000), and bovine lgM (approx. Mr 900 000) .... Capto Core 700 binds proteins up to Mr 660 000 while proteins with higher molecular weight, such as lgM, are excluded from the beads and pass through the column in the flowthrough (Fig 5).).
It would have been obvious to one of ordinary skill in the art at the time of the invention to modify Anderson with the teaching of GE Healthcare. One of ordinary skill in the art would have been motivated to do so with a reasonable expectation of success for the purpose of removing contaminants from viral preparations as taught by GE Healthcare. Merck teaches cell culture medium comprising hCMV and Shield 1 (Para. (0008], methods of making the rdCMV of the invention comprising propagating the rdCMVon epithelial cells, such as ARPE-19 cells (ATCC Accession No. CRL-2302), in the presence of
Shield-1 ). Additionally, It would have been obvious to one of ordinary skill in the art at the time of the invention to modify Anderson with the teaching of Merck for the purpose of growing rdCMV under replication conditions, and purifying CMV into replication deficient conditions as taught by Merck (Para. [0004), The present invention is directed to conditional replication defective CMV (rdCMV) and the use of rdCMV in compositions and methods of treating and/or decreasing the likelihood of an infection by CMV or pathology associated with such an infection in a patient. The rdCMV described herein comprises a nucleic acid encoding one or more fusion proteins that comprise an essential protein fused to a destabilizing protein .... replication is reduced, and preferably prevented, when administered to a patient (in the absence of the stabilizing agent)).
Therefore, the claimed invention would have been prima facie obvious to one of ordinary skill in the art before the effective filing date of the claimed invention.
Claims 20-22 and 24-26 are rejected under 35 U.S.C. 103(a) as being unpatentable over Anderson et al. (US PGPUB 2017/0349634, IDS of record dated 08/23/2024) in view of Zhou (US PGPUB 2007/0167612, IDS of record dated 08/23/2024) and further in view of "Data file 28-9983-07 AA: Multimodal chromatography: Capto Core 700" (hereinafter GE Healthcare, IDS of record dated 08/23/2024) and O’Riordan et al. “O’Riordan” (US PGPUB 2010/0279385, IDS of record dated 08/23/2024).
Regarding Claim 20, Anderson discloses a method for the purification of HCMV from a cell culture medium (Para. (0153], This Example describes methods for production of virus-like particles (VLPs) containing various recombinant HCMV antigens described in Example 1; Para. [0167), VLPs were produced and purified as follows), comprising the steps of: a) harvesting cell culture medium from a culture of ARPE-19 cells infected with HCMV (Para. [0154], After 48 to 72 hours of transfection, supernatants containing the VLPs were harvested and filtered through 0.45 um pore size membranes and further concentrated and purified by ultracentrifugation; Para. [0158), The serum/HCMV mixtures were added to human foreskin fibroblasts (HFF) or retinal pigmented epithelial cells (ARPE-19 cells) grown on
coverslips in 24 well tissue culture plates and incubated for 2 hours at 37° C., 5% CO2); c) clarifying the nuclease-treated cell culture medium using filtration and ultracentrifugation to obtain a clarified cell culture medium (Para. [0167}. The cells were cultured for 72 hours, and then the cultures were centrifuged at 4000 rpm for 20 minutes, using rotor JS-4.2A by Beckman Coulter, in 1 L bottles. The supernatant was filtered through 0.8/0.45 nm filter (AcroPak 500 Capsule, Pall). The filtered supernatant was then concentrated by Tangential Flow Filtration (TFF) and diafiltered against histidine-containing buffer); d) contacting the clarified cell culture medium comprising HCMV with an anion exchange chromatography media under conditions that allow the HCMV to bind to the anion exchange chromatography membrane and then eluting the HCMV from the anion exchange chromatography membrane to obtain an eluate (Para. [0167]. The diafiltered material was loaded onto an anion exchange chromatography column (AEX); Para. [0169], AEX column chromatography was used to reduce DNA contenL .. Loading was performed at 3.2 mUmin, after which the column was washed with 5 column volumes of equilibration buffer, or until the base line was observed; Para. [0169]. The column was then stripped by 5 column
volumes of stripping buffer (20 mM Histidine+1000 mM NaCl, pH 5.5) and the peak was collected. This was followed by 5 column volumes of another stripping buffer (20 mM Histidine+2000 mM NaCl, pH 5.5) to remove any strongly bound proteins and nucleic acids and the peak was collected; Para. [0170], As shown in FIG. 11, intact gB-G monovalent VLPs are present after TFF (FIG. 11A) and AEX
purification (FIG. 118)); and f) performing tangential flow filtration on the purified HCMV collected from step e) to adjust to the desired concentration and buffer (Para. [0113), VLPs may be purified according to known techniques, such as centrifugation, gradients, sucrose-gradient ultracentrifugation, tangential flow filtration and chromatography (e.g., ion exchange (anion and cation), affinity and sizing column chromatography); Para. [0167], The filtered supernatant was then concentrated by Tangential Flow Filtration (TFF) and diafiltered against histidine-containing buffer).
Anderson fails to explicitly disclose b) subjecting the cell culture medium to nuclease treatment using an endonuclease at a concentration of 10-160 U/mL, a 1.2 um glass fiber filter, an anion exchange chromatography membrane, e) contacting the eluate with a mixed-mode chromatography resin which is a hydrophobic anion exchange chromatography resin having a molecular weight exclusion of about 700
kDa and then collecting the HCMV from the mixed mode chromatography resin to obtain purified HCMV.
Zhou, however, teaches membranes for anion exchange purification of targets (Para. [0024), One family of anion exchangers used in various embodiments of the present invention, referred to as "Q-anion exchangers," includes Q membranes and Q chromatography columns. Q membranes and Q chromatography resins operate as basic anion-exchange adsorbers, and are based on quaternary ammonium salts).
It would have been obvious to one of ordinary skill in the art at the time of the invention to modify Anderson with the teaching of Zhou. One of ordinary skill in the art would have been motivated to do so with a reasonable expectation of success for the purpose of using a disposable chromatography step as taught by Zhou (Para. (0025], a Q membrane may be directly loaded with the eluate collected from a cation-exchange chromatography column, following an about one-fold dilution, having a conductivity of
about 3.5-4.5 mS/cm after being titrated to a pH of about 7 .2. A Q membrane is generally used once and then disposed, therefore eliminating a cleaning validation step from the anion exchanger- polishing protocol). GE Healthcare teaches b) subjecting the cell culture medium to nuclease treatment using an endonuclease, and e), contacting the eluate with a mixed-mode chromatography resin which is a hydrophobic anion exchange chromatography resin having a molecular weight exclusion of about 700 kDa and then collecting the HCMV from the mixed mode chromatography resin to obtain purified HCMV (Pg. 1, Col. 1, Para. 1, Capto Core 700 is designed for intermediate purification and polishing of viruses and other large biomolecules. The novel core bead technology and multimodal, octylamine ligand (hydrophobic anion exchange) give Capto Core 700 dual-functionality, size separation, and binding chromatography in one chromatography medium (resin); Pg. 1, Col. 1, Para. 4, The core of each bead is
functionalized with ligands that are both hydrophobic and positively charged, resulting in a highly efficient multimodal binding of various contaminants; Pg. 3, Col. 1, Para. 1, Effective removal of HCP and DNA, Most HCP are negatively charged above pH 7. The ligands of Capto Core 700 are positively charged below a pKa of 10.6, and a pH of 7 to 9 is therefore recommended to ensure good binding of HCP. DNA is negatively charged over a wider pH range and the efficiency of the DNA removal is thus less dependent on pH. It is, however, recommended that DNA/RNA levels are reduced prior to the Capto Core 700 purification step, for example, by use of an anion exchange step or by treatment with Benzonase ™ endonuclease. Degradation of DNA using Benzonase yields small oligonucleotide fragments that enter the core of the beads where these bind to the internal ligands. Benzonase will also enter the core and bind, and will thus be removed from the virus flow through fraction).
It would have been obvious to one of ordinary skill in the art at the time of the invention to modify Anderson with the teaching of GE Healthcare. One of ordinary skill in the art would have been motivated to do so with a reasonable expectation of success for the purpose of removing contaminants from viral preparations as taught by GE Healthcare. O'Riordan teaches 1.2 um glass fiber filters appropriate for clarifying viral cell culture supernates (Abstract, The present invention relates to the purification of large scale quantities of active (infectious) adenovirus and AAV, especially for use in therapeutic applications; Para. [0063], Preferably, purification of adenovirus includes the following steps: pressure lysis of 293 cells infected with adenovirus in the presence of a detergent such as Tween-BO and recovery of virus in the lysate; clarification of lysate by passage through a 3 um glass fiber filter and an 0.8 um cellulose acetate filter; Para. [0057], materials can be cellulose membrane or silica membrane cartridges characterized by high Substrate specificity for target protomers, negligible binding of non-specific proteins, and a pore size (-1.2 um) which is sufficient for purification of the largest known spheroidal viruses. The cartridge design, which consists of a stack of low-binding cellulose or silica membrane filters, is suited to high flow rates, while the large pore size (1.2 m) of the cartridges eliminates the diffusion associated with beaded gel resins packed in columns), and wherein benzonase is present at about 10-160 U/ml (Para. [0091], Following resuspension the cells were lysed using a Microfluidiser (Model HC5000, Microfluidics, Newton, Mass.) at 1000 psi and the lysale was incubated with benzonase (2500 units benzonase R/10 cells) for 1 hour at room temperature. To remove cellular debris, the lysale was clarified by passing ii through glass wool (without vacuum) or by vacuum filtration through 3.0 um glass fiber filters ). It would have been
obvious to one of ordinary skill in the art at the time of the invention to modify Anderson with the teaching of O'Riordan. One of ordinary skill in the art would have been motivated to do so with a reasonable expectation of success for the purpose of using a filter that does not damage the virus as taught by O'Riordan (Abstract, the invention provides improved methods for contacting Such viruses with Suitable chromatographic materials in a fashion Such that any damage to the virus, particularly to Surface
components thereof, resulting from contact with Such chromatographic materials is minimized or eliminated).
Regarding Claim 21, modified Anderson discloses the method of claim 20. Anderson fails to explicitly disclose wherein step b) is run prior to step a) by addition of nuclease to the cell culture medium prior to harvesting. It would have been obvious to one of ordinary skill in the art at the time the invention was made to add nuclease to the culture prior to harvesting, since selection of any order of process steps
which did not result in a new or unexpected result would involve only routine skill in the art. The
motivation with a reasonable expectation of success for doing so would be to effectively remove free DNA from the media as taught by Anderson (Para. [0167), The diafiltered material was loaded onto an anion exchange chromatography column (AEX); Para. (0169), AEX column chromatography was used to
reduce DNA content).
Regarding Claim 22, modified Anderson discloses the method of claim 20. Anderson fails to explicitly disclose wherein step b) is run following step a). GE Healthcare teaches wherein step b) is run following step a) ( Pg. 3, Col. 1, Para. 1, Effective removal of HCP and DNA, Most HCP are negatively charged above pH 7. The ligands of Capto Core 700 are positively charged below a pKa of 10.6, and a pH of 7 to 9 is therefore recommended to ensure good binding of HCP. DNA is negatively charged over a wider pH range and the efficiency of the DNA removal is thus less dependent on pH. It is, however, recommended that DNA/RNA levels are reduced prior to the Capto Core 700 purification step, for example, by use of an anion exchange step or by treatment with Benzonase ™ endonuclease. Degradation of DNA using Benzonase yields small oligonucleotide fragments that enter the core of the beads where these bind to the internal ligands. Benzonase will also enter the core and bind, and will thus be removed from the virus flow through fraction).
It would have been obvious to one of ordinary skill in the art at the time of the invention to modify Anderson with the teaching of GE Healthcare. One of ordinary skill in the art would have been motivated to do so with a reasonable expectation of success for the purpose of removing contaminants from viral preparations as taught by GE Healthcare.
Regarding Claim 24, modified Anderson discloses the method of claim 20. Anderson further discloses wherein the purified HCMV has at least 80% HCMV protein purity (Para. [0044], Isolated substances and/or entities may be separated from about 10% ... or more than about 99% of the other components with which they were initially associated. In some embodiments, isolated agents are about ... 99%, or more than about 99% pure; Para. [0109], Provided VLPs in accordance with the present invention may be prepared according to general methodologies known to the skilled person .... These elements can be isolated and manipulated using techniques well known to the skilled
artisan).
Regarding Claim 25, modified Anderson discloses the method of claim 20. Anderson fails to explicitly disclose wherein the purified HCMV has a yield of at least 40%. O'Riordan teaches chromatographic methods for virus purification having a yield of 40% or more (Abstract, The present invention relates to the purification of large scale quantities of active (infectious) adenovirus and AAV, especially for use in therapeutic applications. In particular, the invention provides improved methods for contacting Such viruses with Suitable chromatographic materials in a fashion such that any damage to the virus, particularly to Surface components thereof, resulting from contact with Such chromatographic
materials is minimized or eliminated; Para. (0136], Table 5 shows the recovery of AAV activity from several purification runs .... The three column purification procedure described above provided an AAV yield of 48% and a purity of >90% pure (FIG. 11 )).
It would have been obvious to one of ordinary skill in the art at the time of the invention to modify Anderson with the teaching of O'Riordan. One of ordinary skill in the art would have been motivated to do so with a reasonable expectation of success for the purpose of purifying therapeutic quantities of virus as taught by O'Riordan (Abstract, The result is the ability to rapidly and efficiently purify commercial level quantities of active (infectious) virus suitable for use in therapeutic applications, e.g. gene
transfer/therapy procedures).
Regarding Claim 26, modified Anderson discloses the method of claim 20. Anderson fails to explicitly disclose wherein the purified HCMV contains 10 ng or less hcDNA per dose. GE Healthcare teaches a chromatographic polishing step that effectively removes essentially all cellular DNA from purified virus preparations ( Pg. 3, Col. 1, Para. 1, Effective removal of HCP and DNA, Most HCP are negatively charged above pH 7. The ligands of Capto Core 700 are positively charged below a pKa of 10.6, and a pH of 7 to 9 is therefore recommended to ensure good binding of HCP. DNA is negatively charged over a wider pH range and the efficiency of the DNA removal is thus less dependent on pH. It is,
however, recommended that DNA/RNA levels are reduced prior to the Capto Core 700 purification step, for example, by use of an anion exchange step or by treatment with Benzonase™ endonuclease. Degradation of DNA using Benzonase yields small oligonucleotide fragments that enter the core of the beads where these bind to the internal ligands. Benzonase will also enter the core and bind, and will
thus be removed from the virus flow through fraction).
It would have been obvious to one of ordinary skill in the art at the time of the invention to modify Anderson with the teaching of GE Healthcare. One of ordinary skill in the art would have been motivated to do so with a reasonable expectation of success for the purpose of removing contaminants from viral preparations as taught by GE Healthcare.
Therefore, the claimed invention would have been prima facie obvious to one of ordinary skill in the art before the effective filing date of the claimed invention.
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 Langi, 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
on line using web-screens. An eTerminal Disclaimer that meets all requirements is autoprocessed
and approved immediately upon submission. For more information about eTerminal
Disclaimers, refer to www.uspto.gov/patents/apply/applying-online/eterminal-disclaimer.
Claims 1-9, 20-22 and 24-26 are rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1-4 of U.S. Patent No. 12060583. Although the claims at issue are not identical, they are not patentably distinct from each other because the claims are coextensive in scope and species with one another.
The patented claims are directed to:
1. A method for the purification of HCMV from a cell culture medium comprising the steps of:
a) harvesting cell culture medium from a culture of ARPE-19 cells infected with HCMV;
b) subjecting the cell culture medium to nuclease treatment using an endonuclease at a concentration of 10-160 U/mL;
c) clarifying the nuclease-treated cell culture medium using a 1.2 μm glass fiber filter to obtain a clarified cell culture medium;
d) contacting the clarified cell culture medium comprising HCMV with an anion exchange chromatography membrane under conditions that allow the HCMV to bind to the anion exchange chromatography membrane and then eluting the HCMV from the anion exchange chromatography membrane to obtain an eluate;
e) contacting the eluate with a mixed-mode chromatography resin which is a hydrophobic anion exchange chromatography resin having a molecular weight exclusion of about 700 kDa and then collecting the HCMV from the mixed mode chromatography resin to obtain purified HCMV; and
f) performing tangential flow filtration on the purified HCMV collected from step e) to adjust to the desired concentration and buffer wherein the cells are grown on microcarriers; wherein the purified HCMV has at least 80% HCMV protein purity and/or a process yield of at least 40%; and wherein the HCMV is a recombinant genetically modified HCMV having a genomic sequence of SEQ ID NO: 1 (instant claims 1-9, 20, 24-25).
2. The method of claim 1, wherein step b) is run prior to step a) by addition of nuclease to the cell culture medium prior to harvesting (instant claim 21).
3. The method of claim 1, wherein step b) is run following step a) (instant claim 22).
4. The method of claim 1, wherein the purified HCMV contains 10 ng or less hcDNA per dose (instant claim 26).
There is no patentable difference between the claimed composition and the patented composition in that the U.S. Patent No. 12060583 discloses a method of purifying human cytomegalovirus (HCMV) from a cell culture medium, the method comprising: a) contacting the cell culture medium comprising HCMV to an anion exchange chromatography medium under conditions that allow the HCMV to bind to the anion exchange chromatography medium; b) eluting the HCMV from the anion exchange chromatography medium to obtain an eluate; c) contacting the eluate with a polishing chromatography medium; and d) collecting the HCMV from the polishing chromatography medium to obtain purified HCMV. The MPEP states “where the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, a prima facie case of either anticipation or obviousness has been established. In re Best, 562 F.2d 1252, 1255, 195 USPQ 430, 433 (CCPA 1977).
Conclusion
No claims are allowed.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Barry Chestnut whose telephone number is (571)270-3546. The examiner can normally be reached on M-Th 8:00 to 4:00.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Thomas Visone can be reached on 571-270-0684. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/BARRY A CHESTNUT/Primary Examiner, Art Unit 1672
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