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 Under 37 CFR 1.114
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 04/03/2026 has been entered.
Withdrawal of Rejections
The response and amendments filed on 04/03/2026 are acknowledged. Any previously applied minor objections and/or minor rejections (i.e., formal matters), not explicitly restated here for brevity, have been withdrawn necessitated by Applicant’s formality correction and/or amendments. For the purposes of clarity of the record, the reasons for the Examiner’s withdrawal, and/or maintaining, if applicable, of the substantive or essential claim rejections are detailed directly below and/or in the Examiner’s Response to Arguments section.
Briefly, the previous claim rejection sunder 35 U.S.C. 103 for obviousness have been withdrawn; however, new grounds of rejection are set forth below.
The following rejections and/or objections are either reiterated or newly applied. They constitute the complete set presently being applied to the instant application.
Claim Rejections - 35 USC § 103, Obviousness
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claims 1-4 and 6 are rejected under 35 U.S.C. 103 as being unpatentable over Ho (KR 20030060150; Date of Publication: July 16, 2003 – cited in the IDS filed on 02/11/2022 – newly cited) in view of Jung (US 2011/0091937; Date of Publication: April 21, 2011 – previously cited), Yun (KR 20170062694; Date of Publication: June 8, 2017 – cited in the IDS filed on 02/11/2022 – newly cited), Lebreton (US 2009/0148435; Date of Publication: June 11, 2009 – previously cited), and Kang (KR 100667860; Date of Publication: January 11, 2007 – previously cited).
Ho’s general disclosure relates to “a method for purifying Clostridium botulinum type A toxin, specifically, (a) adding pH 3 to the culture solution of Clostridium botulinum type A strain 4 to produce a precipitate, and then obtaining a precipitate; (b) dissolving the obtained precipitate in a buffer solution, and then lysing the lysate with ammonium sulfate to obtain a precipitate; (c) suspending the precipitate with phosphate buffer, treating the RNA hydrolase, removing the insoluble one, and then precipitating the supernatant with ammonium sulfate to obtain a precipitate; (d) dissolving the obtained precipitate in a buffer solution, and then performing ion exchange chromatography to obtain only a fraction having a value of A260 / 280 of 0.6 or more; (e) performing gel permeation chromatography on the obtained fractions” (see, e.g., Ho, English Translation, abstract).
Regarding claim 1 pertaining to preparing botulinum toxin, Ho teaches Clostridium botulinum type A strain cultures were acidified with 3N sulfuric acid until pH 3.5. After standing for 3-4 hours, the upper layer was carefully removed from the lower layer with a clear upper layer and a cloudy precipitate, and the lower layer was centrifuged at 2,400 × g at 4 ° C. for 20 minutes to obtain a precipitate (see, e.g., Ho, English Translation, Example – Step 1). Furthermore, Ho teaches “The precipitate was dissolved and eluted with 0.1 M citrate buffer (0.1 M citric acid-trisodium citrate butter, pH 5.5) for about 1 hour. Centrifugation (9800xg, 20 minutes, 4 ° C) was performed to obtain a solution. After repeating the above procedure again, the eluate was again precipitated at 4 ° C. overnight with ammonium sulfate (35.1 g / 100ml)” (see, e.g., Ho, English Translation, Example – Step 2). After treatment overnight with ammonium sulfate, Ho teaches “The precipitate obtained by centrifugation (12,000 × g, 20 min, 4 ° C.) was dissolved in phosphate buffer (0.005 M Na 2 HPO 4 -NaH 2 PO 4 buffer, pH 6.0), followed by RNA hydrolase (50 mg / ml). Was added and reacted at 37C for 3 hours. Again, this was centrifuged at 23,700 g for 20 minutes at room temperature to remove insoluble matters, and again the supernatant was treated with ammonium sulfate (35.1 g / 100 ml) and precipitated at 4 ° C. overnight” (see, e.g., Ho, English Translation, Example – Step 3). Therefore, one of ordinary skill in the art would readily understand that the nucleic acid removal process via RNA hydrolase was performed after, not before, the first addition of ammonium sulfate. Moreover, Ho teaches “The precipitate obtained by centrifugation (17,600 × g, 20 minutes, 4 ° C.) was eluted with 0.05 M phosphate buffer (pH 5.5), and then dialyzed with dialysis membrane (Spectrum Co, USA, MW Cut-off: 12,000) and then dished out. The insoluble material was removed by centrifugation (17,600 × g, 15 min, 23 ° C.) and passed through a DEAE-Sephadex A50 column (Pharmacia, Sweden) equilibrated with 0.05M citrate buffer at a rate of 0.5 ml per minute. The first peak (fractions with a value of A260 / A280 of 0.6 or greater) was then obtained which flowed into the same buffer solution” (see, e.g., Ho, English Translation, Example – Step 4). After anion exchange chromatography, Ho teaches the purified botulinum toxin was treated “with ammonium sulfate (35.1 g / 100ml) and centrifuge (17,600xg, 15 minutes, 4 ° C) to precipitate again, elute it again with 0.05M citrate buffer (pH 5.0), then centrifuge (17,600xg) , 15 min, 23° C.) to remove insoluble matter” (see, e.g., Ho, English Translation, Example – Step 5).
Regarding claim 3 pertaining to the acid precipitation in step (b), Ho teaches “Clostridium botulinum type A strain cultures were acidified with 3N sulfuric acid until pH 3.5” (see, e.g., Ho, English Translation, Example – Step 1).
Regarding claim 4 pertaining to the buffer in step (c), Ho teaches after acid precipitation with sulfuric acid, “The precipitate was dissolved and eluted with 0.1 M citrate buffer (0.1 M citric acid-trisodium citrate butter, pH 5.5) for about 1 hour” (see, e.g., Ho, English Translation, Example – Step 2).
Regarding claim 6 pertaining to the ammonium sulfate in step (c), Ho teaches the eluate was again precipitated at 4 ° C. overnight with ammonium sulfate (35.1 g / 100ml)” (see, e.g., Ho, English Translation, Example – Step 2). One of ordinary skill in the art would readily understand that 35.1 g / 100ml of ammonium sulfate is equivalent to 35.1% (w/v) of ammonium sulfate (see, e.g., MPEP 2144.05(I)).
However, Ho does not teach: culturing Clostridium botulinum in a culture medium containing 6,10,14- trimethylpentadecan-2-one and free of animal-derived components to produce botulinum toxin (claim 1, step (a)); or performing ultrafiltration or buffer replacement using a dialysis tube on the purified botulinum toxin resulting from step (d) (claim 1, step (e)); or performing secondary anion-exchange chromatography using a quaternary ammonium- crosslinked beaded agarose column to obtain purified botulinum toxin wherein the botulinum toxin is obtained as a botulinum toxin-containing fraction from a flow through (FT) eluted from anion-exchange chromatography (claim 1, step (f)); or performing cation-exchange chromatography using a column comprising cross-linked beaded poly(styrene-divinylbenzene) particles surface coated with a polyhydroxylated polymer functionalized with sulfopropyl to concentrate botulinum toxin; wherein the chromatography process in the steps (d), (f), and (g) are each performed using 10mM or 50mM sodium citrate buffer with pH 4.5 to pH 6.5, and wherein the sodium citrate buffer used in steps (f) and (g) is identical in composition (claim 1, step (g)); or wherein the culture medium in the step (a) further contains a yeast extract and glucose (claim 2).
Jung’s general disclosure relates to “a method of producing Clostridium botulinum toxin
by using a media containing plant-derived components” (see, e.g., Jung, abstract). Moreover,
Jung discloses “that a large amount of Clostridium botulinum toxin was expressed outside the
cell by using a composition of plant-derived components, and Clostridium botulinum toxin could
be effectively produced by using a disposable bioreactor through fermentation that u sed strict
anaerobes, Clostridium botulinum strains. In addition, the inventors of the present application
found that Clostridium botulinum toxin could be easily and very simply purified from the culture
from which the cell was removed” (see, e.g., Jung, [0010]).
Regarding claim 1 pertaining to step (a) of culturing Clostridium botulinum, Jung teaches
culturing Clostridium botulinum in plant-derived components (see, e.g., Jung, claim 1).
Additionally, Jung teaches that the culture medium contains 6,10,14-trimethylpentadecan-2-one,
or phytone peptone (see, e.g., Jung, claim 2).
Yun’s general disclosure relates to “producing a botulinum toxin by an animal product free (APF) process. More particularly, the present invention relates to a method for producing a botulinum toxin, After adding the buffer solution to the precipitate containing the botulinum toxin, the buffer solution was added to the filtrate by using depth filtration (DF), microfiltration (MF), ultrafiltration (UF), sterile filtration, Clarification through one or more methods selected from the group consisting of membrane chromatography (MC) and centrifugation; A solution containing the purified botulinum toxin is subjected to UF diafiltration, ammonium sulfate precipitation, or hydrochloric acid precipitation, and then the dialyzed retentate of the UF diaphylacture is diluted in a buffer solution, or ammonium sulfate Dissolving the precipitate of the precipitate or the hydrochloric acid precipitate in the buffer solution; And purifying the botulinum toxin using anion exchange chromatography (AEX) on a diluted dialyzed artifact, a lysate of an ammonium sulfate precipitate, or a lysate of a hydrochloric acid precipitate” (see, e.g., Yun, English Translation, abstract).
Regarding claim 1 pertaining to steps e-f, Yun teaches first anion exchange chromatography followed by secondary anion exchange chromatography (see, e.g., Yun, English Translation, steps e-f, pg. 6). Furthermore, Yun teaches “performing a UF diafiltration, ammonium sulfate precipitation, or hydrochloric acid precipitation on the solution containing the purified botulinum toxin in step (b), and then performing a dialysis retention of the UF diaphylacture, To a buffer solution, or to dissolve a precipitate of ammonium sulfate precipitation or hydrochloric acid precipitation in a buffer solution” (see, e.g., Yun, English Translation, pg. 4). Moreover, Yun teaches “In the present invention, in the step (f), the secondary anion exchange chromatography has a pH of 2 to 9, preferably 3 to 8, a conductivity of 2 to 40 mS / cm, preferably 3 to 30 mS / cm. In the step (f), the botulinum toxin may be obtained by fractionating the flow through from the anion exchange chromatography into a fraction containing the botulinum toxin (flow through mode, and a binding mode with a fraction containing a botulinum toxin bound to a resin of anion exchange chromatography” (see, e.g., Yun, English Translation, pg. 7). Moreover, Yun teaches “In the method for preparing a botulinum toxin according to the present invention, the resin used for anion exchange chromatography includes diethylaminoethyl (DEAE), quaternary aminoethyl (QAE) and quaternary amine (Q) groups” (see, e.g., Yun, English Translation, pg. 7). Yun teaches “Cellular ion exchange resins such as DE23, DE32, DE52, CM-23, CM-32 and CM-52 are commercially available from GE Healthcare, Lindesnes, Norway, and SEPHADEX- Crosslinked ion exchangers are also known. For example, DEAE-, QAE-, CM-, and SP-SEPHADEX and DEAE-, Q-, CM- and S-SEPHAROSE and SEPHAROSE Fast Flow are both available from GE Healthcare Bio-Sciences. Additionally, DEAE and CM derivatized ethylene glycol-methacrylate copolymers (e.g., TOYOPEARL ™ DEAE-650S or M and TOYOPEARL ™ CM-650S or M) were purchased from Tosoh Bioscience LLC, King of Prussia, PA” (see, e.g., Yun, English Translation, pg. 7). Furthermore, Yun teaches further purifying the botulinum toxin obtained from the secondary anion exchange chromatography using cation exchange chromatography (see, e.g., Yun, English Translation, pg. 6), wherein “the resin used for the cation exchange chromatography comprises carboxymethyl (CM), sulfoethyl (SE), sulfopropyl (SP), phosphate (P) and sulfonate” (see, e.g., Yun, English Translation, pg. 7).
Regarding claim 2 pertaining to the culture medium, Yun teaches “the medium for culturing Clostridium botulinum strains may include casein hydrolyzate, yeast extract, glucose, etc.” (see, e.g., Yun, English Translation, pg. 5).
Lebreton’s general disclosure relates to a method of purifying an antibody by cation
exchange chromatography with a high pH wash step to remove contaminants prior to eluting the
protein (see, e.g., Lebreton, abstract). Moreover, Lebreton discloses “a method for purifying
antibody from a composition comprising the antibody and at least one contaminant using cation
exchange chromatography, wherein a high pH wash step is used to remove contaminants prior to
eluting the desired antibody using an elution buffer with increased conductivity” (see, e.g.,
Lebreton, [0003]). Additionally, Lebreton discloses “a method for purifying an antibody from a
composition comprising the antibody and at least one contaminant, which method comprises the
sequential steps of: (a) loading the composition onto a cation exchange material wherein the
composition is at a first pH; (b) washing the cation exchange material with a first wash buffer at
a pH which is greater than that of the composition in (a), wherein the pH of the first wash buffer
is from about 6.8 to about 9.0; (c) washing the cation exchange material with a second wash
buffer at a pH which is less than that of the first wash buffer; and (d) eluting the antibody from
the cation exchange material with an elution buffer at a conductivity which is substantially
greater than that of the second wash buffer” (see, e.g., Lebreton, [0012]-[0016]).
Regarding claim 1, step (g) pertaining to the cation-exchange chromatography column,
Lebreton teaches “A preferred cation exchange material herein comprises cross-linked
poly(styrene-divinylbenzne) flow-through particles (solid phase) coated with a polyhydroxylated
polymer functionalized with sulfopropyl groups (for example, POROS 50 HS.RTM.
chromatography resin)” (see, e.g., Lebreton, [0037] & claim 8).
Kang’s general disclosure relates to “a method for purifying ninth factor of high purity human blood coagulation from human plasma, and the method for purifying ninth factor of human blood coagulation of high purity according to the present invention uses human plasma from which cryopaste is removed as a starting material. First eluted using anion exchange chromatography, and then inactivated virus by S / D treatment (Solvent / Detergent treatment), and then secondly eluted again using anion exchange chromatography. In the method for purifying human coagulation factor 9 by concentration and filtration, the eluted solution purified by the second anion exchange chromatography was eluted by using heparin affinity chromatography. After purification, the ratio was qualitatively determined using cation exchange chromatography. After purification by the method of collecting the complex again, further comprising the step of nanofiltration (nanofiltration) to remove the virus” (see, e.g., Kang, English Translation, abstract).
Regarding claim 1, step (g) pertaining to the sodium citrate buffer, Kang teaches sodium citrate in cation exchange chromatography, wherein the sodium citrate is 10-20 mM for the equilibration buffer (see, e.g., Kang, English Translation, Claim 6). Moreover the pH of the sodium citrate buffer is 6.0 to 8.0 (see, e.g., Kang, English Translation, Claim 4) (see, e.g., MPEP 2144.05(I)).
It would have been first obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to culture Ho’s Clostridium botulinum in media comprising 6,10,14-trimethylpentadecan-2-one, as taught by Jung. One would have been motivated to do so because Jung teaches that phytone peptone (i.e., 6,10,14-trimethylpentadecan-2-one) “plays a vital role in expressing Clostridium botulinum type A toxin outside the cell” (see, e.g., Jung, [0055]). Moreover, Ho teaches culturing Clostridium botulinum in order to produce a purified botulinum toxin via anion exchange chromatography and gel permeation chromatography (see, e.g., Ho, English Translation, Example 1, steps 1-5). Therefore, based on the teachings of Kim and Jung, it would have been obvious to culture Clostridium botulinum in media comprising 6,10,14-trimethylpentadecan-2-one in order to express Clostridium botulinum type A toxin outside the cell for subsequent isolation and purification.
It would have been secondly obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to culture Ho’s Clostridium botulinum in media that is free of animal-derived components, as taught by Jung. One would have been motivated to do so because Jung teaches that when plant-derived components are used to culture Clostridium botulinum, more botulinum toxin is secreted outside of the cell, when compared to media comprising animal-derived components (see, e.g., Jung, [0035], [0054]). Moreover, Ho teaches culturing Clostridium botulinum in order to produce a purified botulinum toxin via anion exchange chromatography and gel permeation chromatography (see, e.g., Ho, English Translation, Example 1, steps 1-5). Therefore, based on the teachings of Ho and Jung, it would have been obvious to culture Clostridium botulinum in media free of animal-derived components in order to increase the yield of botulinum toxin. One would have expected success because Ho and Jung both teach the production of botulinum toxin by culturing Clostridium botulinum.
It would have been thirdly obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to purify Ho’s botulinum toxin via primary anion exchange chromatography, wherein after primary anion exchange chromatography, the botulinum toxin undergoes secondary anion exchange chromatography, as taught by Yun. One would have been motivated to do so because Yun teaches that secondary anion exchange chromatography was performed after primary anion exchange chromatography in order to further purity the botulinum toxin protein (see, e.g., Yun, English Translation, Example 2-3-2). Additionally, Yun teaches secondary anion exchange chromatography as a binding mode, wherein the secondary anion exchange chromatography further refines the sample obtained by primary anion exchange chromatography by having the sample bind to the secondary anion exchange chromatography resin due to a difference in charge (see, e.g., Yun, English Translation, Example 2-3-2). Moreover, Ho teaches anion exchange chromatography for purification of botulinum toxin (see, e.g., Ho, English Translation, Example 1, steps 1-5). Therefore, based on the teachings of Ho and Yun, it would have been obvious to combine primary and secondary anion exchange chromatography in order to obtain a significantly purified and refined botulinum toxin product. One would have expected success because Ho and Yun both teach methods of purifying botulinum toxin via chromatography processes.
It would have been fourthly obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to purify Ho’s botulinum toxin, wherein the purification process includes a cation exchange chromatography column, as taught by Yun, and wherein the cation exchange chromatography column comprises cross-linked beaded poly(styrene-divinylbenzene) particles surface coated with a polyhydroxylated polymer functionalized with sulfopropyl, as taught by Lebreton. One would have been motivated to do so because Lebreton teaches that poly(styrene-divinylbenzene) is a mechanically stable matrix that allow for one or more charged ligands to adhere during the purification process (see, e.g., Lebreton, [0038]). Moreover, Kim teaches cation-exchange chromatography methods for purifying a Clostridium botulinum toxin in order to produce a botulinum toxin at a very high purity and very high yield (see, e.g., Kim, abstract & [0022], [0024], Figures 4-7). Furthermore, Ho teaches culturing Clostridium botulinum in order to produce a purified botulinum toxin via anion exchange chromatography and gel permeation chromatography (see, e.g., Ho, English Translation, Example 1, steps 1-5). Moreover, Kim teaches that anion-exchange chromatography, followed by cation-exchange chromatography, results in production of a botulinum toxin with a very high purity (see, e.g., Kim, [0076]). Therefore, based on the teachings of Ho, Kim, and Lebreton, it would have been obvious to use a column comprising cross-linked beaded poly(styrene-divinylbenzene) particles surface coated with a polyhydroxylated polymer functionalized with sulfopropyl for purification of the botulinum toxin. Furthermore, based on the teachings of Ho, Kim, and Lebreton, it would have been obvious to perform cation exchange chromatography after anion exchange chromatography in order to produce a botulinum toxin with a very high purity. One would have expected success because Ho, Kim, and Lebreton both teach the purification of proteins using chromatography.
It would have been fifthly obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to purify botulinum toxin via primary anion exchange chromatography, secondary anion exchange chromatography, and cation exchange chromatography, as taught by Ho and Yun, wherein the chromatography steps are all performed with sodium citrate buffer, as taught by Ho and Kang. One would have been motivated to do so because Kang teaches sodium citrate in cation exchange chromatography, wherein the sodium citrate is 10-20 mM for the equilibration buffer (see, e.g., Kang, English Translation, Claim 6). Moreover the pH of the sodium citrate buffer is 6.0 to 8.0 (see, e.g., Kang, English Translation, Claim 4). Moreover, Ho teaches primary anion exchange chromatography wherein “the insoluble material was removed by centrifugation (17,600 × g, 15 min, 23 ° C.) and passed through a DEAE-Sephadex A50 column (Pharmacia, Sweden) equilibrated with 0.05M citrate buffer at a rate of 0.5 ml per minute” (see, e.g., Ho, English Translation, Example – Step 4). Since Ho successfully teaches the use of sodium citrate in primary anion exchange chromatography, this is motivation for one of ordinary skill in the art to use sodium citrate in the secondary anion exchange chromatography process. Moreover, this would result in teachings and motivation to use the same sodium citrate buffer in all chromatography steps. Based on the teachings of Ho, Yun, and Kang, it would have been obvious to use sodium citrate as the buffer in all chromatography processes since Ho and Kang both teach that anion and cation exchange chromatography can be successfully performed with this buffer. One would have expected success because Ho, Yun, and Yun all teach purification of proteins using chromatography.
Regarding claim 1, step(d)’s packing volume limitations, those working in the biological and/or pharmaceutical arts would understand that adjustments of particular conventional working conditions (e.g., volumes, concentrations, amounts, etc.) is deemed a matter of judicious selection and routine optimization, which is within the purview of the skilled artisan. For example, Ho teaches purification of botulinum toxin by anion exchange chromatography, wherein the insoluble material was removed by centrifugation (17,600 × g, 15 min, 23 ° C.) and passed through a DEAE-Sephadex A50 column (Pharmacia, Sweden) equilibrated with 0.05M citrate buffer at a rate of 0.5 ml per minute (see, e.g., Ho, English Translation, Example – Step 4). Moreover, Yun also teaches anion exchange chromatography for purification of botulinum toxin, wherein “Cellular ion exchange resins such as DE23, DE32, DE52, CM-23, CM-32 and CM-52 are commercially available from GE Healthcare, Lindesnes, Norway, and SEPHADEX- Crosslinked ion exchangers are also known. For example, DEAE-, QAE-, CM-, and SP-SEPHADEX and DEAE-, Q-, CM- and S-SEPHAROSE and SEPHAROSE Fast Flow are both available from GE Healthcare Bio-Sciences. Additionally, DEAE and CM derivatized ethylene glycol-methacrylate copolymers (e.g., TOYOPEARL ™ DEAE-650S or M and TOYOPEARL ™ CM-650S or M) were purchased from Tosoh Bioscience LLC, King of Prussia” (see, e.g., Yun, English Translation, pg. 7). Moreover, Yun teaches “TQ resin was packed on column XK 26/40 to a height of 30 ~ 34 cm” (see, e.g., Yun, English Translation, Example 2-3-1). Since anion exchange chromatography is used in these methods to purify botulinum toxin, one of ordinary skill in the art would be motivated to optimize the packing volume of the column to obtain optimal protein purification. This is motivation for one of ordinary skill in the art to practice or test the parameter widely to find out those that are functional or optimal which then would be inclusive of the steps as instantly claimed. Moreover, one of ordinary skill in the at would readily understand that manipulating the packing volume of the anion exchange chromatography column would affect protein purification efficiency. Absent any teaching of criticality by the Applicant concerning the packing volume, it would be prima facie obvious that one of ordinary skill in the art would recognize these limitations are result effective variables which can be met as a matter of routine optimization.
Regarding claim 1(g)’s composition limitations, such as concentration and pH of the sodium citrate, MPEP 2144.05 states that “Generally, differences in concentrations or temperatures will not support the patentability of subject matter encompassed by the prior art unless there is evidence indicating such concentration or temperature is critical. Where 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”. Those working in the biological and/or pharmaceutical arts would understand that adjustments of particular conventional working conditions (e.g., concentration or amount of a compound, pH of a solution, etc.) is deemed a matter of judicious selection and routine optimization, which is within the purview of the skilled artisan. For example, the disclosure of Jung states “It will be understood by one of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the following claims” (see, e.g., Jung, [0072]). Furthermore, Kang teaches sodium citrate in cation exchange chromatography, wherein the sodium citrate is 10-20 mM for the equilibration buffer (see, e.g., Kang, English Translation, Claim 6). Moreover the pH of the sodium citrate buffer is 6.0 to 8.0 (see, e.g., Kang, English Translation, Claim 4). Moreover, Ho teaches primary anion exchange chromatography wherein “the insoluble material was removed by centrifugation (17,600 × g, 15 min, 23 ° C.) and passed through a DEAE-Sephadex A50 column (Pharmacia, Sweden) equilibrated with 0.05M citrate buffer at a rate of 0.5 ml per minute” (see, e.g., Ho, English Translation, Example – Step 4). Therefore, Ho and Kang both teach sodium citrate between a pH of 4.5 and 6.5, and a concentration of 10 mM or 50 mM, for anion and cation exchange chromatography. This is motivation to use these pH and concentrations of sodium citrate for all chromatography processes since Ho and Kang teach that chromatography can successfully be performed with this composition of sodium citrate. Furthermore, this is motivation for one of ordinary skill in the art to practice or test the parameter widely to find out those that are functional or optimal which then would be inclusive of the steps as instantly claimed. Furthermore, one of ordinary skill in the art would understand that manipulating the concentration and/or pH of sodium citrate within the buffer(s) would affect the purification efficiency within the anion and cation exchange chromatography methods. Absent any teaching of criticality by the Applicant concerning the compositions comprising sodium citrate, it would be prima facie obvious that one of ordinary skill in the art would recognize these limitations are result effective variables which can be met as a matter of routine optimization.
Regarding claim 6’s concentration of ammonium sulfate, those working in the biological and/or pharmaceutical arts would understand that adjustments of particular conventional working conditions (e.g., volumes, concentrations, amounts, etc.) is deemed a matter of judicious selection and routine optimization, which is within the purview of the skilled artisan. For example, Ho teaches the eluate was again precipitated at 4 ° C. overnight with ammonium sulfate (35.1 g / 100ml)” (see, e.g., Ho, English Translation, Example – Step 2). One of ordinary skill in the art would readily understand that 35.1 g / 100ml of ammonium sulfate is equivalent to 35.1% (w/v) of ammonium sulfate. Additionally, based on the teachings of Ho, one of ordinary skill in the art would readily understand that the concentration of ammonium sulfate would affect precipitation of the eluate. This is motivation for one of ordinary skill in the art to practice or test the parameter widely to find out those that are functional or optimal which then would be inclusive of the steps as instantly claimed. Absent any teaching of criticality by the Applicant concerning the concentration of ammonium sulfate, it would be prima facie obvious that one of ordinary skill in the art would recognize these limitations are result effective variables which can be met as a matter of routine optimization.
Examiner’s Response to Arguments
Regarding Applicant’s arguments pertaining to Kim and Xiang (remarks, pages 7-9), as discussed above, all previous 35 U.S.C. 103 rejections were withdrawn; however, new grounds of rejection are set forth above. Kim and Xiang were not relied upon in the above presented rejection; therefore, Applicant’s arguments are moot.
Regarding Applicant’s argument that Lebreton does not teach or suggest the use of a 10 mM or 50 mM sodium citrate buffer at a pH of 4.5 to 6.5 with an identical composition for anion and cation exchange chromatography (remarks, page 8), this argument is not persuasive because Lebreton was not relied upon to teach this limitation. Instead, as discussed above, Ho and Kang both teach sodium citrate between a pH of 4.5 to 6.5, and a concentration of 10 mM or 50 mM, for anion and cation exchange chromatography (see, e.g., Kang, English Translation, Claims 4 & 6) (see, e.g., Ho, English Translation, Example – Step 4). One of ordinary skill in the art would be motivated to use sodium citrate at 10 mM or 50 mM, and pH of 4.5 to 6.5, because Ho and Kang teach the same sodium citrate composition for anion and cation exchange chromatography for the purpose of purifying botulinum toxin.
Regarding Applicant’s argument pertaining to the teachings of Kang (remarks, pages 8-9), this argument is not persuasive because Kang was relied upon in the above presented rejection to teach the concentration and pH of the sodium citrate buffer during cation exchange chromatography. Kang was not relied upon to teach the concentration and pH of sodium citrate in anion exchange chromatography. Instead, Ho was relied upon to teach the concentration and pH of the sodium citrate buffer during anion exchange chromatography. Moreover, as discussed above, Ho and Kang teach identical sodium citrate buffer compositions for anion and cation exchange chromatography.
Regarding Applicant’s argument pertaining to the volume of the DEAE-Sepharose column not being taught by prior art (remarks, page 10), this argument is not persuasive because, as discussed above, the packing volume is deemed a matter of routine optimization. Applicant has not provided evidence that the packing volume is critical to the instantly claimed invention; therefore, absent any teaching of criticality by the Applicant concerning the packing volume, it would be prima facie obvious that one of ordinary skill in the art would recognize these limitations are result effective variables which can be met as a matter of routine optimization. Moreover, as stated above, merely changing the packing volume, or even concentration and pH of sodium citrate within the buffer, is a matter of routine optimization. MPEP 2144.05(II)(A) states "It is a settled principle of law that a mere carrying forward of an original patented conception involving only change of form, proportions, or degree, or the substitution of equivalents doing the same thing as the original invention, by substantially the same means, is not such an invention as will sustain a patent, even though the changes of the kind may produce better results than prior inventions." (In re Williams, 36 F.2d 436, 438, 4 USPQ 237 (CCPA 1929)). Furthermore, the instant specification specifically states “The inventors of the present invention attempted to establish an optimum process with high toxin production yield by changing conditions of some steps of the basic process of Example 1” (see, e.g., instant specification, [0079]); therefore, Applicant’s invention in merely routine optimization of a pre-existing protocol.
Regarding Applicant’s argument that the use of 10 mM or 50 mM sodium citrate buffer is absent from the cited references (remarks, page 10), this argument is not persuasive because Ho teaches “The insoluble material was removed by centrifugation (17,600 × g, 15 min, 23 ° C.) and passed through a DEAE-Sephadex A50 column (Pharmacia, Sweden) equilibrated with 0.05M citrate buffer at a rate of 0.5 ml per minute” (see, e.g., Ho, English Translation, Example – Step 4). Additionally, Kang teaches sodium citrate in cation exchange chromatography, wherein the sodium citrate is 10-20 mM for the equilibration buffer (see, e.g., Kang, English Translation, Claim 6). Moreover the pH of the sodium citrate buffer is 6.0 to 8.0 (see, e.g., Kang, English Translation, Claim 4) (see, e.g., MPEP 2144.05(I)). Therefore, Ho and Kang teach these limitations pertaining to sodium citrate.
Regarding Applicant’s argument pertaining to unexpected results (remarks, pages 11-13), this argument is not persuasive because Applicant’s results are not commensurate in scope with the claimed invention. Applicant directed the Examiner to Examples 3 and 4, which rely on soytone media or phytone peptone medium (see, e.g., instant specification, [0086]), as well as buffer replacement after treatment with 60% ammonium sulfate (see, e.g., instant specification, [0093]). Therefore, Applicant is relying on a specific medium and percentage of ammonium sulfate, which are not part of the instantly claimed invention. Even if one were to presume there is some unexpected data, the data is not commensurate in scope with the claimed invention (see, e.g., MPEP 716.02(d)). Moreover, Applicant merely provides statements that the results are unexpected over the cited art; however, Applicant does not provide evidence comparing the instantly claimed invention to the prior art to make this claim. Evidence of unexpected properties may be in the form of a direct or indirect comparison of the claimed invention with the closest prior art which is commensurate in scope with the claims. See In re Boesch, 617 F.2d 272, 205 USPQ 215 (CCPA 1980) (see, e.g., MPEP 716.02(b)(III) & 716.02(e)).
Conclusion
Claims 1-4 and 6 are rejected.
No claims are allowed.
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/NATALIE IANNUZO/Examiner, Art Unit 1653
/SHARMILA G LANDAU/Supervisory Patent Examiner, Art Unit 1653
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