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 .
Status of Action/Claims
Receipt of Remarks/Amendments and Declaration filed on 2/5/2026 is acknowledged. Claims 1-5, 7-9, 12-13 and 15-26 are currently pending. Claims 15-26 are withdrawn. Accordingly, claims 1-5, 7-9, 12-13 are presented for examination on the merits for patentability.
Rejection(s) not reiterated from the previous Office Action are hereby withdrawn. The following
rejections are either reiterated or newly applied. They constitute the complete set of rejections
presently being applied to the instant application.
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.
Claim(s) 1-5 and 12-13 is/are rejected under 35 U.S.C. 102(a)(1) as being anticipated by JPH0284401A (‘401).
Regarding claims 1, 3-5, ‘401 teaches cellulose particulate material made via spray drying, comprising porous polymeric particles, the average pore diameter being from 2 to 50 nm, and having a particle diameter/size of less than 100 microns which anticipates/reads on the claimed volume mean particle diameter D[4,3] of less than 100 microns, and they specifically teach wherein the volume of pores is greater than 0.10 cm3/g, specifically a pore volume of 0.3 cm3/g or more, and wherein the surface area of the material is greater than 10 m2/g, specifically 20 m2/g or more, and wherein the average pore diameter is from 10 to 30 nm, specifically greater than or equal to 10 nm (0.01 microns) (See abstract; claims; examples 1-2; Table 1;).
Regarding the recitation wherein the material is obtained by spray drying a polymer solution and the polymer solution is a solution comprising the cellulosic polymer is a product-by-process limitation. With regards to the product by process limitations of instant claims, MPEP §2113(I) states: “[E]ven though product-by-process claims are limited by and defined by the process, determination of patentability is based on the product itself. The patentability of a product does not depend on its method of production. If the product in the product-by-process claim is the same as or obvious from a product of the prior art, the claim is unpatentable even though the prior product was made by a different process.” (In re Thorpe, 227 USPQ 964,966). Once the Examiner provides a rationale tending to show that the claimed product appears to be the same or similar to that of the prior art, although produced by a different process, the burden shifts to applicant to come forward with evidence establishing an unobvious difference between the claimed product and the prior art product (In re Marosi, 710 F.2d 798, 802, 218 USPQ 289, 292 (Fed. Cir. 1983), MPEP 2113). Thus, the method steps recited in claim 1 do not appear to impart any structural limitations to the particulate material of claim 1, beyond wherein the polymer is a cellulosic polymer, and as such this structural limitation is the only limitation being given patentable weight at this time since ‘401 already teaches spray drying cellulose formulations to form particulates having the claimed properties/features.
Regarding claim 2, ‘401 teaches examples 1 and 2 of spray dried cellulose particulates wherein the particle diameter/size of less than 50 microns, specifically 10 microns (sample A from example 1) and 48 microns (sample B from example 2) which anticipates/reads on the claimed volume mean particle diameter D[4,3] of less than 50 microns.
Regarding claim 12, applicants appear to be trying to define their claimed product via their process of making the claimed particulate material. In the instant case, the solvents used to spray dry applicant’s particles as claimed in claim 12 do not further limit the particles themselves as claimed in claim 1 which were already known in the art to be formed via spray drying and to have the same features which are instantly claimed as is discussed above in the rejection of claim 1. Thus, because claim 12 does not further limit the actual particulate material of claim 1, ‘401 still reads on and anticipates this claim. With regards to the product by process limitations of instant claim 12, MPEP §2113(I) states: “[E]ven though product-by-process claims are limited by and defined by the process, determination of patentability is based on the product itself. The patentability of a product does not depend on its method of production. If the product in the product-by-process claim is the same as or obvious from a product of the prior art, the claim is unpatentable even though the prior product was made by a different process.” (In re Thorpe, 227 USPQ 964,966). Once the Examiner provides a rationale tending to show that the claimed product appears to be the same or similar to that of the prior art, although produced by a different process, the burden shifts to applicant to come forward with evidence establishing an unobvious difference between the claimed product and the prior art product (In re Marosi, 710 F.2d 798, 802, 218 USPQ 289, 292 (Fed. Cir. 1983), MPEP 2113). Thus, the method steps recited in claim 12 do not appear to impart any structural limitations to the particulate material of claim 1.
Regarding claim 13, ‘401 expressly teaches that when their particles are mixed with a crude drug that has sublimation properties such as aspirin, the active ingredient/drug is adsorbed into the pores, and the dissolution rate of the active ingredient (drug) becomes significantly faster (See sentence beginning: Furthermore, when the present invention is physically mixed with a crude drug… ).
Claim Rejections – 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claims 7-9 is/are rejected under 35 U.S.C. 103 as being unpatentable over JPH0284401A (‘401) as applied to claims 1-5 and 12-13 above, and further in view of US5354556.
Determination of the scope and content of the prior art
(MPEP 2141.01)
JPH0284401A (‘401) teaches the particulate material of claims 1-5, and 12-13 as discussed above and incorporated herein.
Ascertainment of the difference between prior art and the claims
(MPEP 2141.02)
Regarding claims 7-9, JPH0284401A (‘401) does not teach wherein the cellulose is a cellulose ether or cellulose ester, specifically one of the claimed cellulose derivatives of claim 8, more specifically cellulose acetate butyrate.
However, this deficiency in JPH0284401A (‘401) is addressed by US5354556.
US5354556 teaches that it was known to spray dry applicant’s preferred cellulose derivative, cellulose acetate butyrate with drugs, e.g. theophylline or erythromycin (see Examples 1 and 10; Col. 5, ln.52-Col. 6, ln. 39).
Finding of prima facie obviousness
Rationale and Motivation (MPEP 2142-2143)
It would have been obvious to one of ordinary skill in the art at the time of the instant filing to switch out the cellulose of ‘401 for the cellulose acetate butyrate of US5354556 because it is an alternative cellulose that is known to be effective when spray dried with drugs to afford effective delivery of the drugs in the microparticles of cellulose acetate butyrate that are formed, one of ordinary skill in the art would be motivated to do this to provide further cellulose particles which offer good/highly effective absorption/adsorption of drugs into the pores formed by the process taught by ‘401. One of ordinary skill in the art would want to use the spray drying process of ‘401 with the cellulose acetate butyrate of US5354556 because US5354556 teaches that spray drying allows for selection of inlet and outlet temperatures, the rate of introduction of the spray, size of spray tip, concentration of active to polymer thereby allowing for highly optimizable particles to afford the desired size, etc. to yield the most/more effective delivery of the incorporated drug.
In light of the forgoing discussion, the Examiner concludes that the subject matter defined by the above claims would have been obvious to one of ordinary skill in the art within the meaning of 35 USC 103(a).
From the teachings of the references, it is apparent that one of ordinary skill in the art would have had a reasonable expectation of success in producing the claimed invention. Therefore, the invention as a whole would have been prima facie obvious to one of ordinary skill in the art, as evidenced by the references, especially in the absence of evidence to the contrary.
Claims 1-5, 7-9, 12-13 are rejected under 35 U.S.C. 103 as being unpatentable over Sparks et al. (US 5,354,556; Oct. 11, 1994) in view of Shen et al. (US 2011/0244002A1; Oct. 6, 2011).
Determination of the scope and content of the prior art
(MPEP 2141.01)
Sparks throughout the reference teaches a controlled release powder containing microparticles for use in pharmaceutical and other controlled in release compositions. The microparticles have an average size in the range of from 0.1 to 125 μm, preferably from 5 to 100 μm, which overlaps the particle diameter recited in claims 1 and 2. The particles also have a degree of porosity. The dissolution rate of the particles is found to relate to the degree of porosity of said particles. The microparticles are obtained by forming a solution of a polymer in a solvent, dissolving or dispersing an active ingredient in the polymer solution to form the mixture, and removing the solvent from the mixture to obtain microparticles. Preferred solvent include water and acetone. Sparks teaches obtaining the microparticles by spray drying the polymer solution. Specifically, Sparks teaches the mixture of active ingredient and polymer in the solvent is sprayed into a stream of hot air in a conventional manner. This causes the solvent to evaporate and the powder containing microparticles is collected in the spray drying vessel. Sparks teaches wherein the polymer is cellulose acetate butyrate. (see e.g., Abstract; col. 3, lines 45-64; col. 5-6; col. 9, line 50-68; Examples; Entire Document).
Ascertainment of the difference between prior art and the claims
(MPEP 2141.02)
While Sparks does not expressly teach the specific pore diameter, volume of pores and the surface area of the material as recited in instant claims 1 and 3-5, Sparks does teach the particles have a degree of porosity. The dissolution rate of the particles is found to relate to the degree of porosity of said particles. Sparks also teaches the size of the particles may be controlled in a number of ways, for example, by Pre-selecting the inlet and outlet temperature of the spray drying vessel; the rate of introduction of the spray, the size of the spray tip or the ratio of the concentration of active ingredient to polymer. Also, the particle size may be controlled by the rate of mixing, the viscosity of the external liquid phase, the viscosity of the internal phase, the active ingredient particle size or the volatility of the solvent. The initial burst of release of active ingredient is considered to be active ingredient lying close to the surface of the particles. The dissolution rate is dependent on the amount of active ingredient remaining in the particle matrix at any given time (col. 6, line 26 to col. 7, line 24; col. 9, line 40-57).
Shen et al. further addresses this deficiency in Sparks.
Shen teaches mesoporous composition comprising an active ingredient which is also obtained by spray drying process. The mesoporous composition has a particle size of about 0.1 μm to about 100 μm. Pores of said mesoporous composition have a mean diameter of about 2 nm to about 30 nm. Pores of said mesoporous composition have a mean volume of about 0.8 cm3/g to about 3.0 cm3/g. The mesoporous materials have surface areas of about 300 to about 2000 m2/g and more preferably have specific surface areas of about 400 to 1200 m2/g. Shen teaches the architecture, size and volume of the pores can be modified in order to achieve a tailored release profile. (Abstract; Claims; Para 0061, 0067, 0071; Entire Document).
Finding of prima facie obviousness
Rationale and Motivation (MPEP 2142-2143)
It would have been obvious to one of ordinary skill in the art at the time of the instant filing to have combined the teachings of Sparks and Shen and formulate a polymeric material comprising porous polymeric particles having the specific pore diameter, volume of pores and the surface area of the material as recited in instant claims 1 and 3-5. As discussed supra, Sparks teaches the particles have a degree of porosity. The dissolution rate of the particles is found to relate to the degree of porosity of said particles. Shen teaches the architecture, size and volume of the pores can be modified in order to achieve a tailored release profile. Thus, one skilled in the art would have found it obvious to optimize the pore diameter and volume of pore based on the desired dissolution rate and/or release profile of the active drug ingredient. Also, as discussed supra, Sparks teaches the initial burst of release of active ingredient is considered to be active ingredient lying close to the surface of the particles. The dissolution rate is dependent on the amount of active ingredient remaining in the particle matrix at any given time. Thus, one skilled in the art would have found it obvious to optimize the surface area of the microparticle based on the desired initial burst of release of active ingredient as having a larger surface area would allow for more active ingredient close to the surface of the particles and hence, higher initial burst of release. Further, Shen teaches similar mesoporous composition comprising an active ingredient which is also obtained by spray drying process and Shen teaches the mesoporous composition having pore diameter, volume of pores and surface area which are the same as instantly claimed. Since Sparks is silent on the specific pore diameter, volume of pores and surface area of the microparticles, it would have been obvious to one skilled in the art to utilize the teachings of Shen for the size, volume and surface area of the microparticles and pores in the microparticles. “The normal desire of scientists or artisans to improve upon what is already generally known provides the motivation to determine where in a disclosed set of percentage ranges is the optimum combination of percentages.” In re Hoeschele, 406 F.2d 1403, 160 USPQ 809 (CCPA 1969). See MPEP 2144.05. Moreover, as discussed supra, Sparks teaches the same method steps of making the porous microparticles as instantly claimed and therefore, the resulting product of Sparks would necessarily have the same size/shapes as are instantly claimed. Additionally, changes in size, shape, or sequence of adding ingredients generally have limited impact on patentability unless they produce unexpected results or solve a specific problem. See: MPEP 2144.04.
In light of the forgoing discussion, the Examiner concludes that the subject matter defined by the above claims would have been obvious to one of ordinary skill in the art within the meaning of 35 USC 103(a).
From the teachings of the references, it is apparent that one of ordinary skill in the art would have had a reasonable expectation of success in producing the claimed invention. Therefore, the invention as a whole would have been prima facie obvious to one of ordinary skill in the art, as evidenced by the references, especially in the absence of evidence to the contrary.
Response to Arguments/Declaration
Applicant in the remarks and declaration argued that in the further experimental tests shown in Annex 2, suspensions of colloidal microcrystalline cellulose (MCC) and nanocrystalline cellulose (NCC), representative of the particles disclosed in prior art ‘401 reference, were spray dried and compared with MesoPac particles produced by spray drying of cellulose solution according to the present invention. Applicant argued the results showed that spray drying a suspension of MCC and NCCC did not produce mesoporous particles while the MesoPAC particles of the present invention have a porous surface. Thus, resultant structure is different to that obtained by spray drying a suspension of cellulose as described in 401.
In response, firstly the examiner argues that the instant claims are directed to a product and the recitation wherein the material is obtained by spray drying a polymer solution and the polymer solution is a solution comprising the cellulosic polymer is a product-by-process limitation. With regards to the product by process limitations of instant claims, MPEP §2113(I) states: “[E]ven though product-by-process claims are limited by and defined by the process, determination of patentability is based on the product itself. The patentability of a product does not depend on its method of production. If the product in the product-by-process claim is the same as or obvious from a product of the prior art, the claim is unpatentable even though the prior product was made by a different process.” (In re Thorpe, 227 USPQ 964,966). Once the Examiner provides a rationale tending to show that the claimed product appears to be the same or similar to that of the prior art, although produced by a different process, the burden shifts to applicant to come forward with evidence establishing an unobvious difference between the claimed product and the prior art product (In re Marosi, 710 F.2d 798, 802, 218 USPQ 289, 292 (Fed. Cir. 1983), MPEP 2113). In the instant case, as discussed supra, ‘401 teaches cellulose particulate material made via spray drying, comprising porous polymeric particles, the average pore diameter being from 2 to 50 nm, and having a particle diameter/size of less than 100 microns which anticipates/reads on the claimed volume mean particle diameter D[4,3] of less than 100 microns, and they specifically teach wherein the volume of pores is greater than 0.10 cm3/g, specifically a pore volume of 0.3 cm3/g or more, and wherein the surface area of the material is greater than 10 m2/g, specifically 20 m2/g or more, and wherein the average pore diameter is from 10 to 30 nm, specifically greater than or equal to 10 nm (0.01 microns) (See abstract; claims; examples 1-2; Table 1;). ‘401 clearly teaches and anticipates the polymeric material product having a porous structure and applicant’s declaration/arguments fail to establish that the claimed product is structurally different than the porous polymeric structure taught by ‘401.
Further, with regards to the declaration filed on 2/5/2026, the magnified image in figure 6 appears to show the NCC particles also having some degree of porosity. Specifically, the bottom right image in figure 6 appears to show there being some degree of porosity in the NCC particle. While the amount or degree of porosity may be different in MESOPAC and NCC particles, however, the image appears to show that there is still some sort of porosity in the NCC as well. Therefore, the results/images provided in the declaration do not appear to have established that the polymer material obtained by spray drying a polymer suspension is non-porous.
Regarding the 103 rejection over Sparks in view of Shen, applicant argued that office does not identify disclosure in the references that teach or suggests a particulate material that is obtained by spray drying a polymer solution.
In response, as discussed in the 103 rejection above, Sparks teaches the microparticles are obtained by forming a solution of a polymer in a solvent, dissolving or dispersing an active ingredient in the polymer solution to form the mixture, and removing the solvent from the mixture to obtain microparticles. Preferred solvent include water and acetone. Sparks teaches obtaining the microparticles by spray drying the polymer solution. Specifically, Sparks teaches the mixture of active ingredient and polymer in the solvent is sprayed into a stream of hot air in a conventional manner. This causes the solvent to evaporate and the powder containing microparticles is collected in the spray drying vessel. Further, as discussed supra, the results/images provided in the declaration do not appear to have established that the polymer material obtained by spray drying a polymer suspension is non-porous. Thus, applicant’s argument/declaration is also not persuasive to overcome the 103 rejection over Sparks.
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
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/A.S/Examiner, Art Unit 1616
/SUE X LIU/Supervisory Patent Examiner, Art Unit 1616
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