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 Claims
The amendments and arguments filed 15 May 2026 are acknowledged and have been fully considered. Claims 1-2, 7, 22, 26, 34, 37, 45-46, 63-69, 73, and 102-103 are currently pending. No claims are amended; claims 3-6, 8-21, 23-25, 27-33, 35-36, 38-44, 47-62, 70-72, and 74-101 are cancelled; claims 63-69, 73, and 102 are withdrawn; no claims are new.
Claims 1-2, 7, 22, 26, 34, 37, 45-46, and 103 are examined on the merits herein.
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.
Claims 1-2, 7, 22, 34, 37, and 103 are maintained rejected under 35 U.S.C. 103 as being unpatentable over Yanase et al. (Vaccine, 2014, Vol. 32, 5918-5924; of record) in view of Alibolandi et al. (J Nanopart. Res., 2015, Vol. 17, 76; of record).
Claim 1 is drawn to a polymersome configured to elicit an immune response to an antigen, comprising:
an amphiphilic block copolymer vesicle comprising an exterior surface and an interior surface; and
the antigen,
wherein the antigen is conjugated to the exterior surface of the polymersome via a covalent bond to a component of the block copolymer, wherein the antigen is not conjugated to the interior surface of the polymersome, and wherein the antigen is a polypeptide.
Yanase et al. teach antigen ovalbumin (OVA) conjugated nanoparticles for eliciting an immune response (Abstract), wherein the nanoparticles are self-assembled polymeric micelles comprising the block copolymer PEG-pGlu and the OVA is covalently conjugated to the surface of the micelles (Sec. 2.1 on pg. 5919).
As such, Yanase et al. teach a polymeric micelle configured to elicit an immune response to an antigen comprising an amphiphilic block copolymer micelle comprising an exterior surface and the antigen, wherein the antigen is conjugated to the exterior surface of the polymeric micelle via a covalent bond to a component of the block copolymer, wherein the antigen is not conjugated to the interior of the micelle, and wherein the antigen is a polypeptide.
The polymeric micelle of Yanase et al. differs from the instantly claimed polymersome in the following ways:
the micelle of Yanase et al. does not comprise a vesicle comprising an interior surface.
Yet, as to 1: Alibolandi et al. teach a comparison of polymeric micelles and polymersomes for medical uses (Abstract). Alibolandi et al. further teach that polymersomes have higher stability and in vitro stability than polymeric micelles (Conclusion on pgs. 14-15).
Therefore, it would have been prima facie obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention to have modified the composition of Yanase et al. by substituting polymersomes in the place of polymeric micelles. It would have been obvious to use the known polymersomes to improve the composition of Yanase et al., by providing higher stability in vitro, with a reasonable expectation of success.
Based on all of the foregoing, claim 1 is rejected as prima facie obvious.
Claim 2 is drawn to the polymersome of claim 1, wherein the covalent bond comprises a thioether bond formed by a sulfhydryl containing compound conjugated to a sulfhydryl-reactive chemical group via alkylation.
Claim 7 is drawn to the polymersome of claim 1, wherein the covalent bond is formed via a linker moiety.
Yanase et al. further teach in Sec. 2.1 (Pg. 5919) the covalent bond between a maleimide group (i.e., a sulfhydryl-reactive group) on the block copolymer and thiolated OVA (i.e., a sulfhydryl containing compound). The modification of the block polymer to comprise a maleimide group reads on a linker moiety as discussed in the instant specification at Par. [0038].
As such, claims 2 and 7 are rejected as prima facie obvious.
Claim 22 is drawn to the polymersome of claim 1, wherein the polymersome has a diameter greater than 70nm.
Claim 103 is drawn to the polymersome of claim 22, wherein the polymersome is between about 100nm to about 1µm.
Yanase et al. further teach an average diameter of 110nm (Sec. 3.1 on pg. 5920), overlapping with the instantly claimed range.
As such, claims 22 and 103 are rejected as prima facie obvious.
Claim 34 is drawn to the polymersome of claim 1, wherein the polymersome has a circumferential membrane of an amphiphilic polymer.
Claim 37 is drawn to the polymersome of claim 34, wherein the amphiphilic polymer comprises a diblock copolymer.
Yanase et al. further teach the use of the amphiphilic diblock copolymer PEG-pGlu (Pg. 5919 left column second paragraph).
As such, claims 34 and 37 are rejected as prima facie obvious.
Claim 2 is ADDITIONALLY rejected under 35 U.S.C. 103 as being unpatentable over Yanase et al. and Alibolandi et al. as applied to claims 1-2, 7, 22, 34, 37, and 103 above, and further in view of Hamley (Biomacromolecules, 2014, Vol. 15, 1543-1559; of record).
Claim 26 is rejected under 35 U.S.C. 103 as being unpatentable over Yanase et al. and Alibolandi et al. as applied to claims 1-2, 7, 22, 34, 37, and 103 above, and further in view of Hamley (Biomacromolecules, 2014, Vol. 15, 1543-1559; of record).
The teachings of Yanase et al. and Alibolandi et al. have been set forth above.
Claim 2 is drawn to the polymersome of claim 1, wherein the covalent bond comprises an amide moiety (Applicant’s elected species).
Yanase et al. and Alibolandi et al. do not teach the antigen being conjugated to the polymersome by an amide moiety.
However, Yanase et al. teach the conjugation of OVA to the PEG terminus of the block polymer (Sec. 2.1 on pg. 5919).
Hamley teaches the formation of PEG-protein conjugates for biotech applications (Pg. 1543 left column first paragraph). Hamley further teaches common coupling chemistries including formation of an amide by reaction of an amine with an NHS ester and forming a thioether bond by reacting a thiol and a maleimide derivative (Fig. 1 on pg. 1544).
Therefore, it would have been prima facie obvious to a person having ordinary skill in the art to have modified the polymersome of Yanase et al. and Alibolandi et al. to utilize an amide linker as taught by Hamley. It would have been obvious to substitute one covalent linker suitable for forming PEG-protein conjugates for biotech applications for another, with a reasonable expectation of success.
Claim 26 is drawn to the polymersome of claim 1, wherein the polymersome is capable of releasing said antigen in an oxidation-independent manner and triggering a humoral immune response, wherein said releasing is an in vivo releasing.
Yanase et al. further teach the OVA causing a humoral immune response in vivo (Sec. 3.2).
And as discussed in MPEP 2112.01, “Products of identical chemical composition cannot have mutually exclusive properties.” In re Spada, 911 F.2d 705, 709, 15 USPQ2d 1655, 1658 (Fed. Cir. 1990). A chemical composition and its properties are inseparable. Therefore, if the prior art teaches the identical chemical structure, the properties applicant discloses and/or claims are necessarily present.
In the instant case, the capability of the cleaving of the covalent bond to the antigen in an oxidation-independent manner is a property that is inherent to the covalent bond. As Yanase et al., Alibolandi et al., and Hamley teach the physical limitations of the instantly claimed polymersome and Applicant’s elected species of covalent linkage, the instantly claimed capability to release the antigen in an oxidation-independent manner is necessarily present.
As such, claim 26 is rejected as prima facie obvious.
Claims 45-46 are rejected under 35 U.S.C. 103 as being unpatentable over Yanase et al. and Alibolandi et al. as applied to claims 1-2, 7, 22, 34, 37, and 103 above, and further in view of Nallani et al. (WO 2014/077781; of record).
Claim 45 is drawn to the polymersome of claim 34, wherein said amphiphilic polymer is polybutadiene-polyethylene oxide (PDB-PEO).
Claim 46 is drawn to the polymersome of claim 34, wherein the polymersome comprises diblock copolymer PBD21-PEO14 (Applicant’s elected species).
Nallani et al. also teach polymersomes as carriers for an immunogen for eliciting an immune response (Abstract). Nallani et al. further teach the use of PBD21-PEO14 as the amphiphilic block copolymer to form the polymersomes (Pars. [0050-51]).
Therefore, it would have been prima facie obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention to have modified the polymersomes of Yanase et al. and Alibolandi et al. to comprise PBD21-PEO14. It would have been obvious to substitute one diblock copolymer suitable for forming polymersomes for delivery of an immunogen for another, with a reasonable expectation of success.
As such, claims 45-46 are rejected as prima facie obvious.
Response to Arguments
Applicant's arguments filed 15 May 2026 have been fully considered but they are not persuasive.
Applicant argues on pgs. 6-8 of the remarks that one of ordinary skill in the art would not look to Alibolandi et al. for modification of Yanase et al. based on the as they are directed to different technical problems, further arguing that there would be no expectation of success for the combination.
This argument is not persuasive. While Alibolandi et al. and Yanase et al. are not directed to the same technical problem, the teachings of Alibolandi et al. are in a relevant field of endeavor to Yanase et al. As discussed in MPEP 2141.01(a), “the field of endeavor is not limited to the specific point of novelty, the narrowest possible conception of the field, or the particular focus within a given field” quoting Unwired Planet, LLC v. Google Inc., 841 F.3d 995, 1001, 120 USPQ2d 1593, 1597 (Fed. Cir. 2016), further discussing the Federal Circuit reads KSR as "direct[ing] us to construe the scope of analogous art broadly" because "familiar items may have obvious uses beyond their primary purposes, and a person of ordinary skill often will be able to fit the teachings of multiple patents together like pieces of a puzzle." Wyers v. Master Lock Co., 616 F.3d 1231, 1238, 95 USPQ2d 1525, 1530 (Fed. Cir. 2010). As both Yanase et al. and Alibolandi et al. are drawn to the delivery of bio-affecting compounds via block polymer-based nanoparticles, they are considered to be analogous art, and one of ordinary skill in the art would reasonably look to Alibolandi et al. to modify the teachings of Yanase et al. Further, as both Yanase et al. and Alibolandi et al. are analogous to the instant application, the combination renders the instant claims prima facie obvious.
Regarding Applicant’s argument that there would be no reasonable expectation for success, the unpredictability discussed by Yanase et al. is an unpredictability in immune response, not an unpredictability in the formation of nanoparticles. As the instant claims are drawn to a polymersome, Yanase et al. teach the formation of block polymer nanoparticles with surface conjugated OVA, and Alibolandi et al. teaches the formation of polymersomes from block polymers, one of ordinary skill in the art would have a reasonable expectation for success in making the instantly claimed polymersomes based on the teachings of Yanase et al. and Alibolandi et al.
Further, the Yanase et al. teach that the physical properties of the NPs could affect immune responses and the structure of OVA on the surface might be optimal for activation of B-cell receptor for antigen, not that the specific parameters are required for the NPs to elicit any immune response. As such, one of ordinary skill in the art would reasonably expect there to be a range for each of the physical parameters of the NPs that are capable of eliciting an immune response. And, as discussed in MPEP 2143.02, Conclusive proof of efficacy is not required to show a reasonable expectation of success. OSI Pharm., LLC v. Apotex Inc., 939 F.3d 1375, 1385, 2019 USPQ2d 379681 (Fed. Cir. 2019) and “the expectation of success need only be reasonable, not absolute”. As Yanase et al. teach that block polymer nanoparticles with surface bound OVA are capable of eliciting an immune response, one of ordinary skill in the art would reasonably expect the polymersome with surface bound OVA of Yanase et al. and Alibolandi et al. to be capable of eliciting a similar immune response, with the extent of the immune response being an optimizable quantity based on the physical properties of the NPs.
Applicant argues on pg. 9 of the remarks that Hamley does not teach vaccine formulation, antigen display, or immunogenic nanoparticle design, and as such does not supply the motivation to combine with Yanase et al. and Alibolandi et al.
This argument is not persuasive. Hamley is not relied on for teaching antigen display or immunogenic nanoparticle design, but for the amide bond linkage between the antigen and block polymer. As discussed in MPEP 2141(I), "In United States v. Adams, . . . [t]he Court recognized that when a patent claims a structure already known in the prior art that is altered by the mere substitution of one element for another known in the field, the combination must do more than yield a predictable result.” As the PEG terminus of the block copolymer conjugated to OVA and the use of amide bonds for conjugating PEG to peptides are both known in the prior art, the substitution of one PEG-peptide linking moiety for another is prima facie obvious.
Conclusion
THIS ACTION IS MADE FINAL. 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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/PAUL HOERNER/Examiner, Art Unit 1611
/CRAIG D RICCI/Primary Examiner, Art Unit 1611
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