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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 6 August 2025 has been entered.
Status of Claims
The amendments and arguments filed 6 August 2025 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. Claim 1 is 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claims 3-6, 8-21, 23-25, 27-33, 35-36, 38-44, 47-62, 70-72, and 74-101 are cancelled; claims 63-69, 73, and 102 are withdrawn; no claims are new.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.
Response to Arguments
Applicant’s arguments, see the Remarks and Declaration, filed 6 August 2025, with respect to the rejection(s) of claim(s) 1-2, 7, 22, 34, 37, 45, and 103 under 35 U.S.C. 103 in over Watson et al., Egli et al., and Discher et al. have been fully considered and are persuasive. Therefore, the rejection has been withdrawn. However, upon further consideration, a new grounds of rejection has been set forth Yanase et al. and Alibolandi et al.
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 rejected under 35 U.S.C. 103 as being unpatentable over Yanase et al. (Vaccine, 2014, Vol. 32, 5918-5924) in view of Alibolandi et al. (J Nanopart. Res., 2015, Vol. 17, 76).
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).
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).
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.
Conclusion
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/PAUL HOERNER/Examiner, Art Unit 1611
/BETHANY P BARHAM/Supervisory Patent Examiner, Art Unit 1611