DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Continued Examination
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 08/11/2025 has been entered.
Status of the Claims
Claims 22-35 have been amended. Claim 36 is canceled. Claims 37-38 are new. Claims 22-35 and 37-38 are currently pending and are examined herein.
Status of the Rejection
All claim objections from the previous office action are withdrawn in view of the Applicant’s amendments.
New grounds of claim objections are necessitated by the amendments as outlined below.
All 35 U.S.C. § 112(b) rejections from the previous office action are withdrawn in view of the Applicant’s amendments.
New grounds of rejection under 35 U.S.C. § 112(b) are necessitated as outlined below.
All 35 U.S.C. § 103 rejections from the previous office action are withdrawn in view of the Applicant’s amendment.
New grounds of rejection under 35 U.S.C. § 103 are necessitated as outlined below.
Information Disclosure Statement
The information disclosure statement (IDS) submitted on 08/11/2025 has been considered by the examiner.
Claim Objections
Claims 22-36 are objected to because of the following informalities:
Claim 22, line b: please amend “Tris” to –Tris buffer—for purposes of consistency with claims 32-33.
Claim 23, line f: please amend “the CE-SDS with capillary temperature below” to – the CE-SDS with the capillary temperature--.
Claim 32, line 2 please amend “the Tris buffer has pH 9” to – the Tris buffer has a pH of 9--.
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.
Claims 22, 25-35 and 37-38 are 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.
Regarding claim 22, line 3, recites the term “impurity” and the scope of the term “impurity” is indefinite as there is no definition or clear boundary in the specification of what is and what is not an impurity in a protein mixture. It is unclear as to what constitutes the scope of an impurity since there is no stated use for the protein mixture and one of ordinary skill in the art would not be able to ascertain what is considered an impurity, especially as “mixture” as recited in claim 22 implies the presence additional chemicals or biochemicals. Therefore, the scope of claim 22 is indefinite. Claims 25-35 and 37-38 are further rejected by virtue of its dependence upon and because it fails to cure the deficiencies of claim 22. The examiner notes that claims 34-35 and 37-38 also recite the term “impurity” and are rejected accordingly.
Regarding claim 26, claim 26 recites “the protein mixture is at least 2 mg/mL”. As the protein mixture is a mixture of several components, it is unclear what component in the mixture has a concentration of at least 2 mg/mL or if, for example, it is the summation of several components. Therefore, the scope of claim 26 is indefinite.
Regarding claim 34, claim 34 recites the term “about 38 kDa” About is a relative term which renders the claim indefinite. The term “about” is not defined by the claim, the specification does not provide a standard for ascertaining the requisite degree, and one of ordinary skill in the art would not be reasonably apprised of the scope of the invention. Furthermore, it is unclear how close to 38kDa a low molecular weight impurity should be to meet this limitation. Therefore, the scope of claim 34 is indefinite.
Claim Rejections - 35 USC § 103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claim(s) 22-28, 30, 34-35, and 37-38 is/are rejected under 35 U.S.C. 103 as being unpatentable over Lee et al. (Capillary Electrophoretic Separation of Poly(ethylene glycol)-Modified Granulocyte-Colony Stimulating Factor, 2010, Arch Pharm Res, Vol 22, No 3, Pages 491-495 ) in view of Fukunaga et al. (Purification and Characterization of the Receptor for Morine Granulocyte Colony-stimulating Factor, 1990, Journal of Biological Chemistry, 265, Pages 14008-14015) and Sanger-van de Griend et al. ( Troubleshooting CE-SDS: baseline disturbances, peak area repeatability and the presence of ghost peaks, 2016, CEPharm 2015 troubleshooting workshop report, Pages 1-7). Guttman et al. (Better Separation Resolution of New Biopharmaceutical Modalities through Fine Tuning of the Temperature with CE-SDS, 2020, SCIEX, Pages 1-5) used as evidence for claims 22-24. Center for Drug Evaluation and Research et al. (Product Quality Reviews 2024, FDA, Pages 1-161, https://www.accessdata.fda.gov/drugsatfda_docs/nda/2018/761075Orig1s000ChemR.pdf used as evidence for claim 38.
Regarding claim 22, a process for improving protein peak separation efficiency in CE-SDS (Lee teaches a process for improving protein peak separation efficiency in SDS-CGE [Figure 7 shows improving peak separation efficiency of the proteins unmodified G-CSF [peak 1] and mono-PEG-20K-G-CSF [peak 2], [Figure 7 and Page 494, Col. 2, Para. 1 of Lee]. SDS-CGE is CE-SDS as evidenced by Guttman which states SDS-CGE also referred to as CE-SDS, [Page, 1, Col. 1, Para. 1 of Guttman]) comprising:
a. Providing a protein mixture comprising a low molecular weight impurity having a molecular weight of 18 kDa, and a protein of interest having a molecular weight of 38kDa (Lee teaches providing a protein mixture sample comprising a low molecular weight unmodified G-CSF impurity and mono-PEG-20K-G-CSF [PEG-G-CSF, a protein of interest] [Figure 7 and Fig. 7 caption, and Page 492, Col. 1, Para. 2 and 3 and Page 492, Col. 1, Para. 2-3]. G-CSF [the same low molecular weight impurity as the instant application] has a molecular weight of 18 kDa, as evidenced by the instant claims 22 and 35 and the instant specification which states the low molecular weight impurity is G-CSF and G-CSF/filgastim has a molecular weight of 18 kDa [see e.g., instant claims 22, 35; Page 5, lines 9-10, Page 6, line 32 -Page 7, line 1 and Page 21, lines 5-9 of the instant specification]. mono-PEG-20K-G-CSF [PEG-G-CSF, the same protein of interest as the instant application] has a molecular weight of 38kDa as evidenced by the instant claim 22 and instant specification which states the protein of interest is PEG-G-CSF and the protein of interest has a molecular weight of 38 kDa [see e.g., Page 6, lines 1-2 of the instant specification and instant claim 22]. Accordingly, products of identical chemical composition cannot have mutually exclusive properties, and thus, the claimed property (i.e., PEG-G-CSF [the protein of interest] having a molecular weight of 38 kDa and G-CSF [the low molecular weight impurity] having a molecular weight of 18 kDa), is necessarily present in the prior art material. [See MPEP 2112.01 (II)]).
b. Mixing the protein mixture with Tris, SDS, Lee teaches the protein mixture sample is mixed with sample buffer, the sample buffer containing Tris HCl buffer and 1% SDS to form a treated protein mixture, [Page 492, Col. 2, Para. 3]);
Lee is silent to and B-mercaptoethanol to form a treated protein mixture.
Fukunaga discloses purification and characterization of the receptor for murine granulocyte colony-stimulating factor and SDS based electrophoresis of G-CSF in a sample buffer containing Tris-HCl and SDS, with the addition of 2-mercaptoethanol as a reducing agent (Title and Page 14009, Col. 2, Para. 4). Fukunaga teaches when the purified G-CSF receptor was electrophoresed after heating with 5% 2-mercaptoethanol, proteins larger than 200 kDa were not observed in Fig. 6A, lanes 3 and 4. Although no reducing agent was included in the buffers used for the purification of the receptor, most of the G-CSF receptor exists as a monomer when electrophoresed under nonreducing conditions on a SDS polyacrylamide gel (Fig. 6A and Page 14012, Col. 2, Para. 1)
Sanger-van de Griend discloses methods for troubleshooting CE-SDS (Title and Page 1, Para. 1). Sanger-van de Griend teaches the CE equivalent of SDS-PAGE is CE-SDS (Page 1, Para. 2). CE-SDS can be performed under reduced conditions. Reduction, typically with beta-mercaptoethanol, reduces the disulfide bonds in a protein and allows the separation of disulphide bonded protein species (Page 1, Para. 2 and Page 2, Para. 1). Sanger-van de Griend further teaches that some users pre-mix beta-mercaptoethanol in the sample buffer to reduce variance between the samples (Page 5, Para. 2).
Lee, Fukunaga and Sanger-van de Griend are considered analogous art to the claimed invention because they are in the same field of electrophoretic- based separations of proteins (Fig. 7 of Lee; Page 1, Para. 2 of Sanger-van de Griend; Page 14009, Col. 2, Para. 4 of Fukunaga). It would have been obvious for one having ordinary skill in the art before the effective filing date of the claimed invention to modify the protein mixture of Lee to include or mix in the reducing agent B-mercaptoethanol to form a treated protein mixture, as taught by Fukunaga and Sanger-van de Griend, since Sanger-van de Griend teaches it would be beneficial for performing reducing conditions in CE-SDS and reduce the disulfide bonds in a protein and allows the separation of disulphide bonded protein species, and furthermore, premixing beta-mercaptoethanol in the sample buffer reduces variance between the samples (Page 2, Para. 1 and Page 5, Para. 2 of Sanger-van de Griend) and Fukunaga teaches it would be beneficial as a reducing agent for G-CSF in SDS-based electrophoresis (Page 14009, Col. 2, Para. 4 and Fig. 6 of Fukunaga). Furthermore, the claimed limitations are obvious because all the claimed elements were known in the prior art and one skilled in the art could have combined the elements as claimed by known methods with no change in their respective functions, and the combination yielded nothing more than predictable results, MPEP 2143[I][A]. Additionally, the selection of a known material, which is based upon its suitability for the intended use, is within the ambit of one of ordinary skill in the art [MPEP § 2144.07];
c. Injecting the treated protein mixture in CE-SDS (Modified Lee teaches injecting the treated protein mixture into a capillary electrophoresis (CE) instrument for performing SDS-CGE/CE-SDS, [see rejection above, Page 492, Col. 2, Para. 3 and Fig. 7 of Lee]); and
d. Performing the CE-SDS with a capillary temperature below 25°C to separate the LMW impurity from the protein of interest having a molecular weight of 38kDa (Modified Lee teaches performing SDS-CGE [CE-SDS] with a capillary temperature of 20ºC, which is below 25ºC, to separate the low molecular weight unmodified G-CSF impurity [peak 1] from the mono-PEG-20K-G-CSF [a protein of interest, peak 2] having a molecular weight of 38 kDa [see rejection of claim 22, limitation a. above, Figure 7 and Fig. 7 caption, and Page 492, Col. 1, Para. 2 and 3 and Page 492, Col. 1, Para. 2-3 of Lee]);
The limitation “wherein performing the CE-SDS with the capillary temperature below 25°C improves the protein peak separation efficiency compared to performing the CE-SDS at 25°C” is an intended result of a positively recited step. The court noted that a "‘whereby clause in a method claim is not given weight when it simply expresses the intended result of a process step positively recited.’" Id. (quoting Minton v. Nat’l Ass’n of Securities Dealers, Inc., 336 F.3d 1373, 1381, 67 USPQ2d 1614, 1620 (Fed. Cir. 2003)). MPEP 2111.04(I). Examiner notes, however, that since the prior art does disclose a process for improving protein peak separation efficiency in CE-SDS comprising substantially the same elements or components as that of the applicant, it is contended that the process of the prior art is capable of an improved protein peak separation efficiency performed at a capillary temperature below 25°C in CE-SDS compared to CE-SDS performed at 25°C. Accordingly, products of identical chemical composition cannot have mutually exclusive properties, and thus, the claimed property (i.e., performing the CE-SDS with the capillary temperature below 25°C improves the protein peak separation efficiency compared to performing the CE-SDS at 25°C), is necessarily present in the prior art material. [See MPEP 2112.01 (II)].
wherein the protein of interest is PEG-G-CSF (Modified Lee teaches the protein of interest is mono-PEG-20K-G-CSF [PEG-G-CSF] [see rejection above, Figure 7 and Fig. 7 caption, and Page 492, Col. 1, Para. 2 and 3 and Page 492, Col. 1, Para. 2-3 of Lee]).
Regarding claim 23, a process for a quantification and/or detection of G-CSF in a protein mixture (Lee teaches a process for the detection of unmodified G-CSF in a protein mixture comprising G-CSF and mono-PEG-20K-conjugated G-CSF, [Abstract and Fig. 7]), the process comprising:
a. Providing the protein mixture comprising G-CSF, PEG-G-CSF, and buffer or water (Lee teaches providing the protein mixture sample comprising the unmodified G-CSF and mono-PEG-20K-G-CSF [PEG-G-CSF], and buffer such as sodium acetate buffer in the unmodified G-CSF solution to which PEG solutions are added [Figure 7 and Fig. 7 caption, and Page 492, Col. 1, Para. 2 and 3]);
b. Mixing the protein mixture with Tris buffer, SDS Lee teaches the protein mixture sample is mixed with sample buffer, the sample buffer containing Tris HCl buffer and 1% SDS to form a treated protein mixture, [Page 492, Col. 2, Para. 3]);
Lee is silent to and B-mercaptoethanol to form a treated protein mixture.
Fukunaga discloses purification and characterization of the receptor for murine granulocyte colony-stimulating factor and SDS based electrophoresis of G-CSF in a sample buffer containing Tris-HCl and SDS, with the addition of 2-mercaptoethanol as a reducing agent (Title and Page 14009, Col. 2, Para. 4). Fukunaga teaches when the purified G-CSF receptor was electrophoresed after heating with 5% 2-mercaptoethanol, proteins larger than 200 kDa were not observed in Fig. 6A, lanes 3 and 4. Although no reducing agent was included in the buffers used for the purification of the receptor, most of the G-CSF receptor exists as a monomer when electrophoresed under nonreducing conditions on a SDS polyacrylamide gel (Fig. 6A and Page 14012, Col. 2, Para. 1)
Sanger-van de Griend discloses methods for troubleshooting CE-SDS (Title and Page 1, Para. 1). Sanger-van de Griend teaches the CE equivalent of SDS-PAGE is CE-SDS (Page 1, Para. 2). CE-SDS can be performed under reduced conditions. Reduction, typically with beta-mercaptoethanol, reduces the disulfide bonds in a protein and allows the separation of disulphide bonded protein species (Page 1, Para. 2 and Page 2, Para. 1). Sanger-van de Griend further teaches that some users pre-mix beta-mercaptoethanol in the sample buffer to reduce variance between the samples (Page 5, Para. 2).
Lee, Fukunaga and Sanger-van de Griend are considered analogous art to the claimed invention because they are in the same field of electrophoretic- based separations of proteins (Fig. 7 of Lee; Page 1, Para. 2 of Sanger-van de Griend; Page 14009, Col. 2, Para. 4 of Fukunaga). It would have been obvious for one having ordinary skill in the art before the effective filing date of the claimed invention to modify the protein mixture of Lee to include or mix in the reducing agent B-mercaptoethanol to form a treated protein mixture, as taught by Fukunaga and Sanger-van de Griend, since Sanger-van de Griend teaches it would be beneficial for performing reducing conditions in CE-SDS and reduce the disulfide bonds in a protein and allows the separation of disulphide bonded protein species, and furthermore, premixing beta-mercaptoethanol in the sample buffer reduces variance between the samples (Page 2, Para. 1 and Page 5, Para. 2 of Sanger-van de Griend) and Fukunaga teaches it would be beneficial as a reducing agent for G-CSF in SDS-based electrophoresis (Page 14009, Col. 2, Para. 4 and Fig. 6 of Fukunaga). Furthermore, the claimed limitations are obvious because all the claimed elements were known in the prior art and one skilled in the art could have combined the elements as claimed by known methods with no change in their respective functions, and the combination yielded nothing more than predictable results, MPEP 2143[I][A]. Additionally, the selection of a known material, which is based upon its suitability for the intended use, is within the ambit of one of ordinary skill in the art [MPEP § 2144.07];
c. Optionally incorporating a 10 kDa marker into the treated protein mixture (This limitation is optional and therefore, does not necessarily limit the claim to the method steps. Thus, Modified Lee meets all the required limitations of this claim.);
d. Injecting the treated protein mixture into a CE-instrument to perform CE-SDS (Modified Lee teaches injecting the treated protein mixture into a capillary electrophoresis (CE) instrument for performing SDS-CGE/CE-SDS, [see rejection above, Page 492, Col. 2, Para. 3 and Fig. 7 of Lee]);
e. Performing the CE-SDS with a capillary temperature below 25°C to separate the G-CSF from the PEG-G-CSF (Modified Lee teaches performing SDS-CGE [CE-SDS] with a capillary temperature of 20ºC [below 25°C] to separate the unmodified G-CSF impurity [peak 1] from the mono-PEG-20K-G-CSF [PEG-G-CSF, peak 2], [see e.g., Figure 7 and Fig. 7 caption, and Page 492, Col. 1, Para. 2 and 3 and Page 492, Col. 1, Para. 2-3 of Lee]. SDS-CGE is CE-SDS as evidenced by Guttman which states SDS-CGE also referred to as CE-SDS, [Page, 1, Col. 1, Para. 1 of Guttman]); and
f. Detecting and/or quantifying the G-CSF (Modified Lee teaches detecting the unmodified G-CSF which is shown in the SDS-CGE electrophoneogram of Fig. 7 of Lee as peak 1, [Figure 7 of Lee]),
The limitation “wherein performing the CE-SDS with capillary temperature below 25°C improves the quantification and/or detection of G-CSF or any other fragment compared to performing the CE-SDS at 25°C” an intended result of a positively recited step. The court noted that a "‘whereby clause in a method claim is not given weight when it simply expresses the intended result of a process step positively recited.’" Id. (quoting Minton v. Nat’l Ass’n of Securities Dealers, Inc., 336 F.3d 1373, 1381, 67 USPQ2d 1614, 1620 (Fed. Cir. 2003)). MPEP 2111.04(I). Examiner notes, however, that since the prior art does disclose a CE-SDS process for detecting unmodified G-CSF in a protein mixture comprising substantially the same elements or components as that of the applicant, it is contended that the process of the prior art is capable of an improved detection of G-CSF with a capillary temperature below 25ºC in CE-SDS compared to CE-SDS performed at 25ºC. Accordingly, products of identical chemical composition cannot have mutually exclusive properties, and thus, the claimed property (i.e., performing the CE-SDS with capillary temperature below 25°C improves the quantification and/or detection of G-CSF or any other fragment compared to performing the CE-SDS at 25°C), is necessarily present in the prior art material. [See MPEP 2112.01 (II)].
Regarding claim 24, a process for an analysis of PEG-G-CSF (Lee teaches a process for an analysis of mono-PEG-20K-G-CSF [PEG-G-CSF], [Abstract and Figure 7]) comprising;
a. Providing a protein mixture comprising the PEG-G-CSF and an unpegylated G-CSF in buffer or water (Lee teaches providing a protein mixture sample comprising unmodified G-CSF [unpegylated G-CSF] and mono-PEG-20K-G-CSF [PEG-G-CSF], and buffer such as sodium acetate buffer in the unmodified G-CSF solution to which PEG solutions are added [Figure 7 and Fig. 7 caption, and Page 492, Col. 1, Para. 2 and 3]);
b. Mixing the protein mixture with Tris buffer, SDS Lee teaches the protein mixture sample is mixed with sample buffer, the sample buffer containing Tris HCl buffer and 1% SDS, to form a treated protein mixture, Page 492, Col. 2, Para. 3);
Lee is silent to and B-mercaptoethanol to form a treated protein mixture.
Fukunaga discloses purification and characterization of the receptor for murine granulocyte colony-stimulating factor and SDS based electrophoresis of G-CSF in a sample buffer containing Tris-HCl and SDS, with the addition of 2-mercaptoethanol as a reducing agent (Title and Page 14009, Col. 2, Para. 4). Fukunaga teaches when the purified G-CSF receptor was electrophoresed after heating with 5% 2-mercaptoethanol, proteins larger than 200 kDa were not observed in Fig. 6A, lanes 3 and 4. Although no reducing agent was included in the buffers used for the purification of the receptor, most of the G-CSF receptor exists as a monomer when electrophoresed under nonreducing conditions on a SDS polyacrylamide gel (Fig. 6A and Page 14012, Col. 2, Para. 1)
Sanger-van de Griend discloses methods for troubleshooting CE-SDS (Title and Page 1, Para. 1). Sanger-van de Griend teaches the CE equivalent of SDS-PAGE is CE-SDS (Page 1, Para. 2). CE-SDS can be performed under reduced conditions. Reduction, typically with beta-mercaptoethanol, reduces the disulfide bonds in a protein and allows the separation of disulphide bonded protein species (Page 1, Para. 2 and Page 2, Para. 1). Sanger-van de Griend further teaches that some users pre-mix beta-mercaptoethanol in the sample buffer to reduce variance between the samples (Page 5, Para. 2).
Lee, Fukunaga and Sanger-van de Griend are considered analogous art to the claimed invention because they are in the same field of electrophoretic- based separations of proteins (Fig. 7 of Lee; Page 1, Para. 2 of Sanger-van de Griend; Page 14009, Col. 2, Para. 4 of Fukunaga). It would have been obvious for one having ordinary skill in the art before the effective filing date of the claimed invention to modify the protein mixture of Lee to include or mix in the reducing agent B-mercaptoethanol to form a treated protein mixture, as taught by Fukunaga and Sanger-van de Griend, since Sanger-van de Griend teaches it would be beneficial for performing reducing conditions in CE-SDS and reduce the disulfide bonds in a protein and allows the separation of disulphide bonded protein species, and furthermore, premixing beta-mercaptoethanol in the sample buffer reduces variance between the samples (Page 2, Para. 1 and Page 5, Para. 2 of Sanger-van de Griend) and Fukunaga teaches it would be beneficial as a reducing agent for G-CSF in SDS-based electrophoresis (Page 14009, Col. 2, Para. 4 and Fig. 6 of Fukunaga). Furthermore, the claimed limitations are obvious because all the claimed elements were known in the prior art and one skilled in the art could have combined the elements as claimed by known methods with no change in their respective functions, and the combination yielded nothing more than predictable results, MPEP 2143[I][A]. Additionally, the selection of a known material, which is based upon its suitability for the intended use, is within the ambit of one of ordinary skill in the art [MPEP § 2144.07];
c. Optionally incorporating a 10 kDa marker into the treated protein mixture (This limitation is optional and therefore, does not necessarily limit the claim to the method steps. Thus, Modified Lee meets all the required limitations of this claim.);
d. Injecting the treated protein mixture in CE-instrument to perform CE-SDS (Modified Lee teaches injecting the treated protein mixture into a capillary electrophoresis (CE) instrument for performing SDS-CGE/CE-SDS, [see rejection above, Page 492, Col. 2, Para. 3 and Fig. 7 of Lee]);
e. Performing the CE-SDS with keeping a capillary temperature below 25°C (Modified Lee teaches performing SDS-CGE [CE-SDS] with a capillary temperature of 20ºC, which is below 25ºC, [Figure 7 and Fig. 7 caption, and Page 492, Col. 1, Para. 2 and 3 and Page 492, Col. 1, Para. 2-3 of Lee]. SDS-CGE is CE-SDS as evidenced by Guttman which states SDS-CGE also referred to as CE-SDS, [Page, 1, Col. 1, Para. 1 of Guttman]); and
f. Analyzing the treated protein mixture to evaluate presence of the unpegylated G-CSF (Modified Lee teaches analyzing the treated protein mixture to evaluate the presence of the unpegylated/unmodified G-CSF [peak 1 in Fig. 7 of Lee], [Figure 7 and Figure 7 caption of Lee]);
The limitation “wherein performing the CE-SDS with the capillary temperature below 25°C improves the analysis of the presence of the unpegylated G-CSF compared to performing the CE-SDS performed at 25°C” is an intended result of a positively recited step. The court noted that a "‘whereby clause in a method claim is not given weight when it simply expresses the intended result of a process step positively recited.’" Id. (quoting Minton v. Nat’l Ass’n of Securities Dealers, Inc., 336 F.3d 1373, 1381, 67 USPQ2d 1614, 1620 (Fed. Cir. 2003)). MPEP 2111.04(I). Examiner notes, however, that since the prior art does disclose a CE-SDS process for analysis of PEG-G-CSF and unpegylated G-CSF comprising substantially the same elements or components as that of the applicant, it is contended that the process of the prior art is capable of an improved analysis of the presence of the unpegylated G-CSF with a capillary temperature below 25ºC in CE-SDS compared to CE- SDS performed at 25ºC. Accordingly, products of identical chemical composition cannot have mutually exclusive properties, and thus, the claimed property (i.e., performing the CE-SDS with the capillary temperature below 25°C improves the analysis of the presence of the unpegylated G-CSF compared to performing the CE-SDS performed at 25°C), is necessarily present in the prior art material. [See MPEP 2112.01 (II)].
Regarding claim 25, the process according to claim 22, wherein the SDS concentration is 1% (Modified Lee teaches the detergent is SDS wherein the concentration is 1% SDS, [Page 492, Col. 2, Para. 3 of Lee]).
Regarding claim 26, the process according to claim 22, wherein the protein mixture is at least 2 mg/mL (Modified Lee teaches the G-CSF solutions which is a component of the protein mixture, as outlined in the rejection of claim 22 above, has a concentration of 3.3 mg/mL, which is greater than at least 2 mg/mL [Page 492, Col. 1, Para. 3 of Lee and see rejection of claim 22 above]).
Regarding claim 27, the process according to claim 22, wherein the protein mixture does not comprise an antibody and/or fragment thereof (Modified Lee teaches the protein mixture sample does not contain an antibody, [Figure 7 and Fig. 7 caption, and Page 492, Col. 1, Para. 2 and 3 of Lee].
Regarding claim 28, the process according to claim 22, wherein the capillary temperature is 20°C (Modified Lee teaches the capillary temperature for CE-SDS/SDS-CGE was 20ºC, [see rejection above, Page 492, Col. 2, Para. 3 of Lee]).
Regarding claim 30, the process according to claim 22, wherein the CE-SDS is performed at a separation voltage at 15 kV or -15kV for at least 30 minutes (Modified Lee teaches the CE-SDS/SDS-CGE is performed at a separation voltage of 15 kV for 40 minutes, which is greater than 30 minutes [see Fig. 7b and Fig. 7 caption, Page 494, Col. 2, Para. 1 of Lee]).
Regarding claim 34, the process according to claim 22, wherein the low molecular weight impurity is less than about 38 kDa (As outlined in the rejection of claim 22 above, Modified Lee teaches the low molecular weight impurity, unmodified G-CSF, is less than about 38 kDa, since it has a molecular weight of 18 kDa, [see e.g., rejection of claim 22, Figure 7 of Lee; Page 492, Col. 1, Para. 1 of Lee; instant claims 22 and 35; [Page 5, lines 9-10, Page 6, line 32 -Page 7, line 1 and Page 21, lines 5-9 of the instant specification]]).
Regarding claim 35, the process according to claim 22, wherein the low molecular weight impurity is G-CSF or any other fragments derived from PEG-G-CSF (As outlined in the rejection of claim 22 above, Modified Lee teaches the low molecular weight impurity is unmodified G-CSF, [Figure 7 and Page 492, Col. 1, Para. 1 of Lee]).
Regarding claim 37, the process according to claim 22, wherein the protein mixture further comprises a high molecular weight impurity (Modified Lee teaches a high molecular weight impurity that is present in the protein mixture. This high molecular weight impurity is di-Peg-20K-G-CSF, shown as peak 3 in Fig. 7B [Figure 7, Page 492, Col. 1, Para. 2-3, Page 494, Col. 2, Para. 1 of Lee]).
Regarding claim 38, the process according to claim 22, wherein the high molecular weight impurity has a molecular weight greater than 38 kDa (Modified Lee teaches the high molecular weight impurity: di-Peg-20K-G-CSF, shown as peak 3 in Fig. 7B. di-Peg-20K-G-CSF has a molecular weight of 58 kDa [G-CSF is 18 kDa, PEG is 20 kDa and di represents two PEG present, thus, 18 kDa + (2 x 20 kDa) = 58 kDa] [see rejection of claim 22 above and Page 19, lines 25-26 of the instant specification]. This is evidenced by the Center for Drug Evaluation and Research which states dipegylated G-CSF has a molecular weight of ~58 kDa [Page 126, Para. 1 Review comment]. Thus, the high molecular weight impurity di-Peg-20K-G-CSF has a molecular weight greater than 38 kDa [see rejection of claim 22 above, Figure 7, Page 492, Col. 1, Para. 2-3, Page 494, Col. 2, Para. 1 of Lee]).
Claim(s) 29 is/are rejected under 35 U.S.C. 103 as being unpatentable over Lee in view of Fukunaga and Sanger-van de Griend as applied to claim 28 above, and further in view of Cetek Corporation et al. (WO2002082066A1), which is cited in the Information Disclosure Statement filed on 01/14/2022.
Regarding claim 29, the process according to claim 28, Modified Lee is silent to wherein the capillary temperature is 15°C.
Cetek Corporation teaches a method for separating and analyzing a protein of interest in capillary electrophoresis (Abstract and Page 2, lines 14-19). Cetek Corporation further teaches the capillary temperature is within a range of about 5ºC to about 37ºC, and the stability of proteins in the capillary can be increased by lowering the capillary temperature during CE (claim 10 and Page 8, lines 20-24).
It would have been obvious to have selected and utilized a capillary temperature within the disclosed range of about 5ºC to about 37ºC, as taught by Cetek Corporation, including those amounts that overlap within the claimed range, since one of ordinary skill in the art would reasonably expect any value within the taught range to be suitable given that Cetek Corporation specifically teaches the range to be suitable for capillary electrophoresis. It has been held that obviousness exists where the claimed ranges overlap or lie inside ranges disclosed by the prior art. See MPEP 2144.05 (I).
Generally, differences in concentration or temperature will not support the patentability of subject matter encompassed by the prior art unless there is evidence indicating such concentration or temperature 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." MPEP § 2144.05(II)(A). Therefore, it would have been obvious to one skilled in the art to use a capillary temperature of 15ºC as this would function is a predictable manner given these conditions.
Claim(s) 31 is/are rejected under 35 U.S.C. 103 as being unpatentable over Lee in view of Fukunaga and Sanger-van de Griend as applied to claim 22 above, and further in view of Sanger-van de Griend et al. (CE-SDS method development, validation, and best practice—An overview, May 2019, Electrophoresis, 40, Pages 2361-2374) and Gu et al. (Assessment of CE-based baseline disturbances using simulation and targeted experimental evaluation—impact on the purity determination of therapeutic proteins, March 2019, Analytical and Bioanalytical Chemistry, 411, Pages 2425-2437).
Regarding claim 31, the process according to claim 22, Modified Lee is silent to wherein the CE-SDS is performed at an injection voltage of 5 kV or -5kV for at least 10 seconds.
However, Lee teaches the samples are injected into the CE-instrument for CE-SDS by pressure injection [Page 492, Col. 2, Para. 3].
Sanger-van de Griend teaches best practice methods for CE-SDS in the characterization of proteins [Abstract]. Sanger-van de Griend further teaches two suitable injection methods: pressure [hydrodynamic injection], which is an alternative to electrokinetic injection, where electrokinetic injection is generally performed in CE-SDS. Electrokinetic injection [injection using an electric field and voltage] is beneficial because it is selective/discriminating [Table 1 and Page 2365, Col. 2, Para. 2-3].
Gu teaches a method for protein analysis using CE-SDS [Abstract]. Gu further teaches an injection protocol for denatured protein samples that are electrokinetically injected at 5kV for 20 seconds, falling within the claimed range of at least 10 seconds. Protein species were then separated with an applied voltage of 15 kV for 40 minutes (Page 2428, Col. 1, Para. 3).
Given the teachings of Sanger-van de Griend regarding pressure injection as an alternative to electrokinetic injection, while electrokinetic injection is generally performed in CE-SDS and the teachings of Gu regarding using an injection protocol for denatured protein samples that are electrokinetically injected at 5kV for 20 seconds, it would have been obvious for one having ordinary skill in the art before the effective filing date of the claimed invention to substitute the pressure injection method of Lee used in CE-SDS with an electrokinetic injection performed at an injection voltage of 5kV for 20 seconds, as taught by Gu, since Gu teaches this injection protocol would be suitable for denatured proteins in CE-SDS (Page 2428, Col. 1, Para. 3 in Gu) and Sanger-van de Griend teaches electrokinetic injection would be beneficial because it is selective/discriminating [Table 1 and Page 2365, Col. 2, Para. 2-3 of Sanger-van de Griend]. Furthermore, the simple substitution of one known element for another (i.e., pressure injection with electrokinetic injection) is likely to be obvious when predictable results are achieved (i.e., the sample is injected into the capillary electrophoresis instrument) [MPEP 2143(b)].
Claim(s) 32-33 is/are rejected under 35 U.S.C. 103 as being unpatentable over Lee in view of Fukunaga and Sanger-van de Griend as applied to claim 22 above, and further in view of Lacher et al. (Development, validation, and implementation of capillary gel electrophoresis as a replacement for SDSPAGE for purity analysis of IgG2 mAbs, 2010, J. Sep. Sci, 33, Pages 218-227).
Regarding claim 32, the process according to claim 22 Modified Lee is silent to wherein the Tris buffer has pH 9.
However, Lee teaches CE-SDS/SDS-CGE is performed with Tris HCl buffer by forming the treated protein mixture that is injected in the CE-SDS (see rejection of claim 22 above, Page 492, Col. 2, Para. 3 of Lee)
Lacher teaches a method for CGE or CE-SDS analysis of proteins with improved performance and throughput (Abstract, Conclusion, and Page 220, Col. 1, last paragraph). Lacher further teaches the protein samples were prepared using SDS-MW sample buffer [Tris-HCL, 1%SDS, pH 9) and B-mercaptoethanol (Page 219, Col. 1, Paras. 3-4 continued to next column). Lacher teaches the composition for a sample buffer for CE-SDS (Page 219, Col. 1, Para. 3-4 and Abstract, Conclusion). The sample buffer contains Tris-HCl at a pH of 9 and 1% SDS. This sample buffer is used for preparing the protein sample (Page 219, Col. 1, Para. 3-4).
It would have been obvious for one having ordinary skill in the art before the effective filing date of the claimed invention to modify the Tris HCl buffer of Modified Lee to have a pH of 9 as taught by Lacher, since Lacher teaches this composition of sample buffer would be beneficial for preparing protein samples and is a suitable pH for performing CE-SDS (Page 219, Col. 1, Para. 3-4, Abstract, Conclusion, and Page 220, Col. 1, last paragraph of Lacher). Furthermore, the use of a known technique (i.e., Using Tris HCl at a pH of 9, taught by Lacher) to improve similar methods in the same way is likely to be obvious. See KSR International Co. v. Teleflex Inc., 550 U.S. 398, 415-421, USPQ2d 1385, 1395 – 97 (2007) (see MPEP § 2143 [I][C]).
Regarding claim 33, the process according to claim 32, wherein the Tris buffer has a concentration of 60mM to 90mM (Modified Lee teaches the sample buffer contains 0.12M [120 mM] Tris HCl and the sample buffer is then diluted with the sample by mixing 100 mL of the sample with 100 mL of the sample buffer. Therefore, the CE-SDS is performed with Tris buffer at a final concentration of 60 mM [0.12M x 100 mL = M2 x 200 mL; thus M2 = 0.06M or 60 mM], [Page 492, Col. 2, Para. 3 of Lee]. Generally, differences in concentration or temperature will not support the patentability of subject matter encompassed by the prior art unless there is evidence indicating such concentration or temperature 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." MPEP § 2144.05(II)(A).).
Response to Arguments
Applicant's arguments, see Remarks Pgs. 7-10, filed 08/11/2025, with respect to the 35 U.S.C. § 103 rejections have been fully considered and all 103 rejections from the previous office action are withdrawn.
Applicant’s Argument #1:
Applicant argues on pages 8-9 that Lee fails to achieve high peak resolution for mono-PEG-20K-G-CSF (Peak 2). In fact, as shown in Figures 7(A) and 7(B) at both 12 kV and 15 kV running voltages, significant peak broadening is observed. Lee also fails to separate the peaks that elute before the unmodified G-CSF (Peak 1), as evidenced by the merged peaks in Figures 7(A) and 7(B) at both running voltages of 12 kV and 15 kV. Further, Lee states that Capillary Zone Electrophoresis is better than SDS-CGE for separating PEG-G-CSF conjugates. As described above, Lee fails to separate the peaks that elute before the unmodified G- CSF (Peak 1) where it appears to be merged with the G-CSF peak. Applicant submits that Lee fails to teach an efficient method for separating and/or quantifying PEG-GCSF and G-CSF molecule. It is important to note that Lee also attempted to perform the separation process at different voltages (12 kV and 15 kV) but still failed to achieve proper separation.
Examiner’s Response #1:
The examiner respectfully disagrees. In response to applicant's arguments against the references individually, one cannot show nonobviousness by attacking references individually where the rejections are based on combinations of references. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981); In re Merck & Co., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986).
In response to applicant's argument that the references fail to show certain features of the invention, it is noted that the features upon which applicant relies (i.e., high peak resolution for mono-PEG-20K-G-CSF and separating the peaks that eluted before the unmodified G-CSF) are not recited in the rejected claim(s). Although the claims are interpreted in light of the specification, limitations from the specification are not read into the claims. See In re Van Geuns, 988 F.2d 1181, 26 USPQ2d 1057 (Fed. Cir. 1993).
In response to applicant’s argument that Lee states that Capillary Zone Electrophoresis is better than SDS-CGE, Lee presents several embodiments such as CE methods and HP-SEC for separation of PEG-G-CSF. The embodiment of capillary zone electrophoresis is not relied upon in the current action. Furthermore, Lee states that CE methods show better separation capacity than HP-SEC for the separation of PEG-G-CSFs (Lee, Page 493, Col. 2, last paragraph). The examiner notes that disclosed examples and preferred embodiments do not constitute a teaching away from a broader disclosure or nonpreferred embodiments. In re Susi, 440 F.2d 442, 169 USPQ 423 (CCPA 1971) "The use of patents as references is not limited to what the patentees describe as their own inventions or to the problems with which they are concerned. They are part of the literature of the art, relevant for all they contain." In re Heck, 699 F.2d 1331, 1332-33, 216 USPQ 1038, 1039. (see MPEP 2123 and 2131.05)
Applicant’s Argument #2:
Applicant argues on page 9 that Lacher does not teach the separation or quantification of the PEG-G-CSF molecule using CE-SDS. Instead, Lacher focuses on the separation of IgG2 monoclonal antibodies (mAbs) by capillary gel electrophoresis. IgG2 monoclonal antibodies are all together different protein in terms of their physiochemical characteristics than PEG-G-CSF. Furthermore, IgG2 monoclonal antibodies do not have PEGylation or attachment of PEG molecule and therefore do not have the same problems (i.e., PEG interference with protein) as PEG-G-CSF.
Applicant further argues that Lacher prefers to perform CE-SDS at capillary temperatures of 25°C and 40°C, in contrast to the presently claimed methods. It is important to note that, Lacher acknowledges that generalization of the CE-SDS method is not applicable to different protein (e.g., IgG1 or IgG4) (see, e.g., page 221, right-hand column). Hence, if Lacher's CE-SDS method for IgG2 is not suitable for IgG1 or IgG4 then it would be difficult for a skilled person to predict its successful use for PEG-G-CSF. Applicant submits that Lacher's teachings are inconsistent with the teachings of Lee. Therefore, a skilled person would not have been motivated to combine Lacher with Lee.
Examiner’s Response #2:
Applicant’s arguments have been fully considered, but are moot in view of the new grounds of rejection. Examiner notes the new grounds of rejection does not rely on any teachings from Lacher applied to the rejection of the independent claims 22-24.
Applicant’s Argument #3:
Applicant argues on 10 that Guttman and CDER fail to remedy the deficiencies of Lee and Lacher. Applicant submits that Guttman merely generally discloses that temperature is one variable of CE-SDS. However, Guttman fails to disclose a method for separating and quantifying PEG-G-CSF by CE- SDS. Accordingly, present independent claims 22-24, and their dependent claims 25-35, 27, and 28, are not obvious in view of the teachings of Lee, alone or in combination with Lacher and Guttman. Applicant submits that a skilled person would not have been motivated to combine the teachings of Lee with Lacher and/or Guttman, let alone arrive at the claimed improved methods. Accordingly, Applicant respectfully requests that the obviousness rejections be reconsidered and withdrawn.
Examiner’s Response #3:
The examiner respectfully disagrees. In response to applicant's arguments against the references individually, such as Guttman fails to disclose a method for separating and quantifying PEG-G-CSF by CE- SDS does not teach the separation or quantification of PEG-G-CSF molecule using CE-SDS, one cannot show nonobviousness by attacking references individually where the rejections are based on combinations of references. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981); In re Merck & Co., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986). Furthermore, Guttman and CDER are used only as evidence references.
Additionally, Applicant’s arguments have been fully considered, but are moot in view of the new grounds of rejection.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. Burgess et al. (Purification of Two Forms of Colony-stimulating Factor from Mouse L-cell-conditioned Medium, 1985, The Journal of Biological Chemistry, 260, Pages 16004-16011) teaches even under mild conditions native CSF can be reduced by mercaptoethanol and dissociation in the presence of mercaptoethanol presumably occurs because the reduction of the disulfide bonds destabilizes the subunit conformation sufficiently to disrupt the interactions between subunit (Page 16007, Col. 2, Para. 2 and 4).
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/S.Y.O./Examiner, Art Unit 1794
/JAMES LIN/Supervisory Patent Examiner, Art Unit 1794
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