DETAILED ACTION
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 February 12, 2026 has been entered.
Previous Rejections
Applicant’s arguments, filed February 12, 2026, have been fully considered. Rejections and/or objections not reiterated from previous office actions are hereby withdrawn. The following rejections and/or objections are either reiterated or newly applied. They constitute the complete set presently being applied to the instant application.
Information Disclosure Statement
The information disclosure statements (IDS) submitted on February 12, 2026 is in compliance with the provisions of 37 CFR 1.97. Accordingly, the information disclosure statement is being considered by the examiner.
Claim Status
Claim 46 is newly added.
Claims 8 – 12, 28 – 30, and 40 – 44 are withdrawn.
Claims 1, 2, 4 – 7, 13, 45 and 46 are examined here-in.
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 non-obviousness.
Claims 1, 2, 4 – 6, 45, and 46 are rejected under 35 U.S.C. 103 as being unpatentable over Twibanire (Twibanire J. K. and Grindley, T.B. “Polyester dendrimers” Polymers 2012, 4, p. 794 – 897) in view of Han (Han, S. et al. “Water-Soluble lipopolymer for gene delivery” Bioconjugate Chemistry 2001, 12, p. 337 – 345).
Twibanire teaches polyester dendrimers are easy to make and non-toxic (abstract, p. 796). Twibanire teaches dendrimers are polymeric molecules that include multiple branched monomers that radiate from a central core (p. 797). Twibanire teaches dendrimers have multiple layers outward from the core which are the dendrimer generation, and that the outermost layer size, shape, and functional groups depend on the number of generations (p. 797, 798). Twibanire teaches that dendrimer diameter increases with generation number, and at low generations a dendrimer has a floppy, flat structure, with more space between the periphery groups, but at higher generations it has increased rigidity and a globular or spherical conformation with much less space between periphery groups (p. 802).
Twibanire teaches dendrimers can be produced via various different chemistries, including ester and click chemistry reactions, thiol-ene reactions, displacement of ketohalides, amide formation, and thioline reactions, amount others (p. 797, 800). Notably, Twibanire explains that the different chemical groups used for core, linker, and periphery will ultimately impact the solubility, degradability, and biological activity of the dendrimer (p. 797).
Twibanire teaches 2,2-bis(hydroxymethyl)propanoic acid is a popular building block for dendrimers because it is commercially available, inexpensive, and results in non-toxic and biodegradable dendrimers, which is advantageous for drug delivery applications (p. 806 – 807).
Twibanire teaches amine-containing polyester dendrimers, with at least one example of 2,2-bis(hydroxymethyl)propanoic acid functionalized with an amine linkage (p. 806, 818). Twibanire teaches that polyester dendrimers with amine functionalities are attractive for drug delivery because the amine groups can serve as buffers to neutralize acids generated during dendrimer degradation (p. 844).
Twibanire does not teach a fatty acid or lipophilic periphery group.
Han teaches the missing element of Twibanire.
Han teaches that lipopolymers are suitable for in vivo gene delivery (abstract).
Han teaches that the lipid group can be a cholesterol or a fatty acid chain (p. 337 column 2). Han teaches that lipid structure enables interaction with cell membranes, wherein the DNA cargo has increased permeation through cell membranes due to lipid character (p. 337 columns 1 and 2).
Han teaches a lipid can be bound to polymer group via an ester, amide or carbamate bond, which will determine chemical stability and biodegradability of the overall complex (p. 337 columns 1 and 2).
The combination of Twibanire and Han’s teachings render claims 1, 2, 4 – 6, 45, and 46 prima facie obvious because Han’s teachings for lipid groups for gene delivery would motivate a person of ordinary skill in the art to include such a group on the polymeric dendrimer compounds of Twibanire (MPEP 2143(i)(g)). Said differently, a person of ordinary skill in the art would be motivated to modify Twibanire’s teaching of a polyester dendrimer for drug delivery (p. 844) to include a lipidic (i.e. fatty acid) peripheral group according to Han’s teachings because Han teaches that a lipid periphery group enables of the drug delivery vehicle interaction with cell membranes, wherein the DNA cargo will have increased permeation through cell membranes (p. 337 columns 1 and 2). The combination of prior art elements based on some teaching, suggestion, or motivation in the prior art that would lead a person of ordinary skill in the art to modify or combine prior art references is prima facie obvious according to MPEP 2143(i)(g).
Twibanire’s teaching for a polyester dendrimers based on 2,2-bis(hydroxymethyl)propanoic acid functionalized with an amine linkage (p. 806, 818), in combination with Han’s teaching to conjugate a lipid to a polymeric carrier group via an amide bond (p. 337 columns 1 and 2) for the delivery of nucleic acids (Twibanire p. 806 – 807, 844, Han p. 337 columns 1 and 2) reads on instant claims 1 and 46. Specifically, Twibanire’s teaching for a polyester dendrimer based on 2,2-bis(hydroxymethyl)propanoic acid reads on the recitation of PE in formula Ia, an amine linker reads on group A, and a lipid group reads on the hydrophobic unit derived from a fatty acid or fatty acid derivative of group B.
Twibanire’s teaching that dendrimers have multiple layers outward from the core which are the dendrimer generation, and various examples with generation numbers ranging from 1 to 4, such as in Scheme 12 (p. 807) reads on instant claims 2 and 4. Twibanire’s teaching that dendrimer shape and diameter changes with generation number, wherein low generations have a floppy, flat structure, with more space between the periphery groups, but at higher generations have increased rigidity and a globular or spherical conformation with much less space between periphery groups (p. 802) would lead a person of ordinary skill in the art to choose a number of generations suitable for the desired drug carrier.
Twibanire’s teaching for 2,2-bis(hydroxymethyl)propanoic acid as a core group for polyester dendrimer (p. 806 – 807) reads on instant claims 5 and 6. A person of ordinary skill in the art would be motivated to choose 2,2-bis(hydroxymethyl)propanoic acid because Twibanire teaches it is commercially available, inexpensive, and results in non-toxic and biodegradable dendrimers, which is advantageous for drug delivery applications (p. 806 – 807).
Han’s teaching that the lipid group can be a fatty acid chain (p. 337 column 2) reads on instant claim 45.
Claims 7 and 13 are rejected under 35 U.S.C. 103 as being unpatentable over Twibanire (as cited above) and Han (as cited above) and further in view of Demeule (US 2016/0015823 A1, of record).
Twibanire and Han’s teachings are discussed above.
The combination of Twibanire and Han does not teach an acetylene carboxylic acid group (claim 7) or N1-(3-aminopropyl)-N1-ethylbutane-1,4 diamine (structure 20, claim 13) as amine linker.
Demeule teaches the missing elements of the combination of Twibanire and Han.
Demeule teaches dendrimers for the delivery of therapeutic agents (abstract). Demeule teaches that dendrimers have a core group that branches to a different moiety in generations (paragraphs 0005 – 0008). Demeule teaches that the core or branch moieties of the dendrimer can be propargylamine, ethylenediamine, triethanolamine, pentaerythritol, azido-propyl(alkyl)amine, hydroxyethyl(alkyl)amine, tetraphenyl methane, trimesoylchloride, diaminohexane, diaminobutane, cysteamine, propylenediamine, propyleneamine, or a molecule with at least three functional groups (paragraphs 0008, 0012, 0028, 0029). Demeule teaches that the functional groups are points at which branching occurs (paragraphs 0028 – 0029).
Demeule teaches that the dendrimer includes linkers which may have 2 to 15 carbon atoms and homobifunctional or heterobifunctional amino groups (paragraph 0058). Demeule teaches that carboxylic acids and acetylene as possible linking groups (paragraph 0058).
The combination of Twibanire, Han, and Demeule’s teachings renders claims 7 and 13 prima facie obvious as combining known elements according to known methods to yield predictable results (MPEP 2143(I)(a)). A person of ordinary skill in the art would have been motivated to implement Demeule’s teachings for various core and linkers with multiple reactive groups (paragraphs 0008, 0012, 0028, 0029) because Twibanire and Han both teach that the combination of different cores, linking groups, and peripheral units determine the chemical stability, biodegradability, and thus drug delivery of the overall complex (Twibanire abstract, p. 796, 797, 800, Han p. 337 columns 1 and 2).
The combination of Twibanire’s teaching for a polyester dendrimers based on 2,2-bis(hydroxymethyl)propanoic acid functionalized with an amine linkage (p. 806, 818), Han’s teaching to conjugate a lipid to a polymeric carrier group via an amide bond (p. 337 columns 1 and 2), and Demeule’s teaching that carboxylic acids and acetylene are suitable reactive groups for linking dendrimer components together (paragraph 0058) reads on instant claim 7.
Demeule’s teaching that the core or branch moieties of the dendrimer can be propargylamine, ethylenediamine, triethanolamine, pentaerythritol, azido-propyl(alkyl)amine, hydroxyethyl(alkyl)amine, tetraphenyl methane, trimesoylchloride, diaminohexane, diaminobutane, cystamine, propylenediamine, propyleneamine, or a molecule with at least three functional groups (paragraphs 0008, 0012, 0028, 0029) reads on instant claim 13. Although Demeule’s named compounds do not overlap exactly on the claimed compounds, the general alkyl backbone structure and presence of amine functional groups at each end is the same. Because there is close structural similarity between Demeule’s teachings and the claimed compounds, claim 13 is prima facie obvious according to MPEP 2144.09(I).
Examiner’s Reply to Attorney Arguments Dated February 12, 2026
Applicant’s arguments with respect to the prior art of Khan and Shanta have been considered but are moot because the new ground of rejection does not these references to address the claims as presented at this time.
Double Patenting
The judicially created doctrine for non-statutory double patenting rejections has been described in detail in the previous action.
Double Patenting over 18/553,624
Claims 1, 2, 4 – 7, 13, 45, and 46 are provisionally rejected on the ground of non-statutory double patenting as being unpatentable over claims 1 – 6, 14 – 18, 22 – 24, 27 – 29, and 46 - 48 of copending Application No. 18/553,624.
Although the claims at issue are not identical, they are not patentably distinct from each other because: instant claim 1 is drawn to a nucleic acid carrier having a polyester dendrimer or dendron, an amine linker (A), a hydrophobic unit (B), and a number of surface groups (z).
Conflicting claim 1 is drawn to a nucleic acid carrier having a polyester dendrimer or dendron, an amine linker (A), a hydrophobic unit (B), and a number of surface groups (z). Formulas Id, Ie, and If each include a polyester dendrimer with an amine linker (A) and a hydrophobic unit (B).
The instant and conflicting claims differ because conflicting claim 1 includes additional structures (Ia, Ib, Ic) not shown in instant claim 1, however, each of these is listed in the alternative.
Conflicting claim 2 recites generation number is in a range from 1 to 10, overlapping on instant claim 2.
Conflicting claim 3 recites the monomeric polyester units are 2,2-bis(hydroxymethyl)propionic acid or 2,2-bis(hydroxymethyl)butyric acid, overlapping on instant claim 1.
Conflicting claim 4 overlaps on instant claim 4.
Conflicting claim 5 overlaps on instant claim 13.
Conflicting claim 6 overlaps on instant claims 1 and 45.
Conflicting claims 14 – 18, 22 – 24, 27 – 29, and 46 – 48 are directed to compositions and methods containing the dendrimer of conflicting claim 1.
This is a provisional non-statutory double patenting rejection because the patentably indistinct claims have not in fact been patented.
Examiner’s Reply to Attorney Arguments Dated February 12, 2026
The provisional non-statutory double patenting rejections for 17/414,193 and 18/130,122 have been withdrawn because these conflicting claims recite the inclusion of a PEG moiety. Applicant does not make an argument regarding the provisional non-statutory double patenting rejection for 18/553,624, instead indicating that these rejections will be addressed only if allowable subject matter is indicated (Remarks page 18). According to MPEP 804(1), a complete response to a non-statutory double patenting rejection is either a showing that the claims subject to the rejection are patentably distinct from the reference claim or the filing of a terminal disclaimer. The Examiner notes that Applicant’s argument is not a showing that the claims are patentably distinct from the reference claims. As such, the provisional non-statutory double patenting rejection for 18/553,624 is maintained.
Conclusion
All claims are rejected. No claims are allowed.
Correspondence
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Toriana N. Vigil whose telephone number is (571)270-7549. The examiner can normally be reached Monday - Friday 9:00 a.m. - 5:00 p.m. EST.
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/TORIANA N. VIGIL/Examiner, Art Unit 1612
/SAHANA S KAUP/Supervisory Primary Examiner, Art Unit 1612
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