Prosecution Insights
Last updated: August 06, 2026
Application No. 18/263,955

IONIZABLE LIPID MOLECULE, PREPARATION METHOD THEREFOR, AND APPLICATION THEREOF IN PREPARATION OF LIPID NANOPARTICLE

Final Rejection §103§DP
Filed
Aug 02, 2023
Priority
Feb 05, 2021 — CN 202110159969.3 +1 more
Examiner
SHOMER, ISAAC
Art Unit
1612
Tech Center
1600 — Biotechnology & Organic Chemistry
Assignee
Immorna (Hangzhou) Biotechnology Co. Ltd.
OA Round
2 (Final)
63%
Grant Probability
Moderate
3-4
OA Rounds
0m
Est. Remaining
94%
With Interview

Examiner Intelligence

Grants 63% of resolved cases
63%
Career Allowance Rate
753 granted / 1190 resolved
+3.3% vs TC avg
Strong +30% interview lift
Without
With
+30.3%
Interview Lift
resolved cases with interview
Typical timeline
2y 11m
Avg Prosecution
49 currently pending
Career history
1242
Total Applications
across all art units

Statute-Specific Performance

§101
1.0%
-39.0% vs TC avg
§103
45.9%
+5.9% vs TC avg
§102
11.5%
-28.5% vs TC avg
§112
25.8%
-14.2% vs TC avg
Black line = Tech Center average estimate • Based on career data from 1190 resolved cases

Office Action

§103 §DP
DETAILED ACTION Applicants’ arguments, filed 26 May 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 Rejections and/or objections not reiterated from previous office actions are hereby withdrawn.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. Claim Rejections - 35 USC § 103 – Obviousness 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. Claim(s) 1, 4-7, 9-10, 15-20 and 32-34 is/are rejected under 35 U.S.C. 103 as being unpatentable over Baryza et al. (US 2018/0369386 A1) in view of Beckwith et al. (US 2017/0275243 A1) Baryza et al. (hereafter referred to as Baryza) is drawn to lipids for the delivery of active agents, as of Baryza, title and abstract. One lipid taught by Baryza has the following structure, as of Baryza, page 89, paragraphs 1025 and 1029, wherein the structure from paragraph 1029 is reproduced below. PNG media_image1.png 272 810 media_image1.png Greyscale This structure reads on most of the required features of the instant claims, as set forth in the following table that was generated by the examiner and is set forth on the next page. Claimed Variable Feature in Baryza [1029] Q Benzene ring (albeit oriented in 1,3,5 orientation, which differs from claimed invention) L2 and L3 -O(CH2)x wherein x=1 R4, R5, R6, and R7 All hydrogen b and c b=4 and c=4 when x=1 L1 and L4 Both -C(=O)O- wherein the carbon faces the benzene ring R2, R3, R8, and R9 All hydrogen a and d Both 11 R1 and R10 Both methyl groups L5, R11, and e Not taught by Baryza R12 and R13 Both C1 hydrocarbyl (i.e. methyl) As such, the structure on paragraph 1029 of Baryza differs from the claimed invention because (a) the structure of Baryza lacks the required L5, R11, and e, and (b) the structure of Baryza fails to teach the 1,2,5 substitution pattern around the benzene ring, instead teaching a 1,3,5 substitution pattern around the benzene ring. However, Baryza teaches the following structure on page 59, paragraph 0746, relevant structure reproduced below with annotation by the examiner. PNG media_image2.png 250 732 media_image2.png Greyscale The above-noted portion of the structure reads on the claim requirements in the following manner: Claimed Element Feature in Baryza [0746] L5 -(CH2)y-OC(=O)- wherein y=1 R11 Hydrogen e 2 R12 and R13 Both C1 hydrocarbyl (i.e. methyl) The structure as of Baryza, paragraph 0746, differs from the claimed structure because it does not include both (L2 and L3) and (L1 and L4) together in the same molecule. It would have been prima facie obvious for one of ordinary skill in the art to have substituted the amine-containing headgroup of the structure of paragraph 0746 of Baryza in place of the amine-containing headgroup of the structure of paragraph 1029 on the lipid of paragraph 1029 of Baryza. Both the headgroups of the lipid of paragraph 0746 of Baryza and of paragraph 1029 of Baryza are ionizable cationic lipid headgroups which would have been useful for forming a composition for delivery of siRNA or mRNA, as of paragraph 0013 of Baryza. As such, the skilled artisan would have been motivated to have substituted the headgroup of the compound of paragraph 0746 of Baryza in place of that of paragraph 1029 of Baryza in order to have predictably formed a cationic lipid capable of delivering RNA with a reasonable expectation of success. The simple substitution of one element (e.g. the headgroup of paragraph 0746 of Baryza) in place of another (e.g. the headgroup of the structure of paragraph 1029 of Baryza) to obtain predictable results (formation of an ionizable cationic lipid to deliver RNA) is prima facie obvious. See MPEP 2143, Exemplary Rationale B. Baryza differs from the claimed invention because Baryza teaches 1,3,5 substitution around the benzene ring, whereas the instant claims require 1,2,5 substitution around the benzene ring – this is the case even with the above-indicated substitution. Beckwith et al. (hereafter referred to as Beckwith) is drawn to a lipid for the delivery of active agents, as of Beckwith, title and abstract, and teaches nucleic acid delivery in paragraph 0061. Beckwith teaches a number of lipids with a benzene ring in the center and a 1,2,5 orientation around the benzene ring, including but not limited to the following chemical structure as of Beckwith, page 47, structure at bottom of page, reproduced below. PNG media_image3.png 200 746 media_image3.png Greyscale Beckwith differs from the claimed invention because Beckwith does not teach the required variables L1 and L4. in contrast, at the positions where L1 and L4 are located, there is an ester group wherein the oxygen faces the benzene ring; in contrast, the claimed invention requires an ester group where the carbonyl carbon faces the benzene ring. The examiner notes that this deficiency appears to be present in all of the structures of Beckwith that have an ester at this position; see e.g. Beckwith, paragraphs 0480, 0483, 0485, and 0487 for other examples of this. It would have been prima facie obvious for one of ordinary skill in the art to have rearranged the structure of Baryza to have had oriented the substituents on the benzene ring in a 1,2,5 manner rather than a 1,3,5 manner. Both Baryza and Beckwith are drawn to ionizable cationic lipids for delivery of nucleic acids having a benzene ring with three substituents thereon. Baryza teaches these substituents oriented in a 1,3,5 manner; however, Beckwith teaches orienting these substituents in a 1,2,5 manner. As such, the skilled artisan would have been motivated to have used a 1,2,5 substitution around the benzene ring in place of a 1,3,5 substitution in order to have predictably formed an ionizable cationic lipid capable of delivery of a nucleic acid with a reasonable expectation of success. The simple substitution of one element (a 1,2,5 substitution pattern) in place of another (a 1,3,5 substitution pattern) in order to achieve predictable results (formation of a cationic lipid capable of delivery of a nucleic acid) is prima facie obvious. See MPEP 2143, Exemplary Rationale B. As to claim 4, the structure of Baryza, paragraph 0746, teaches that y=2. As to claim 5, the structure of Baryza teaches that a and d are 11, which exceeds the claimed requirements. Nevertheless, elsewhere in the document, Baryza teaches lipids with shorter groups in the positions of a and d. One example of this is Baryza, paragraph 0779, relevant structure reproduced below. PNG media_image4.png 222 752 media_image4.png Greyscale This structure of paragraph 0779 of Baryza differs from the claimed structure because it lacks the required L5 and because the carbonyl groups face the opposite direction as compared with what is required by the instant claims. Nevertheless, the structure of paragraph 0779 of Baryza appears to comprise a and d as 6. As such, Baryza appears to teach a value for a and d that ranges from 6, as in the structure of paragraph 0779 to 11, as in the structure of paragraph 1029. This overlaps with the claimed requirement. While the prior art does not disclose the exact claimed values, but does overlap: in such instances even a slight overlap in range establishes a prima facie case of obviousness. See MPEP 2144.05(I). As to claim 6, Baryza teaches b=4 in paragraph 1029. As to claim 7, Baryza teaches e=2 in paragraph 0746. As to claim 9, the structure of Baryza that would have been made via the combination of Baryza, paragraphs 1029 and 0746 differs from the structure of compound I of claim due to the lengths of various alkyl chains. Specifically, the alkyl chain between the phenolic oxygens (L2 and L3) and the ester group (L1 and L4) is longer than what is required by the instant claims, the alkyl group between the ester groups (L1 and L4) is shorter than what is required by the instant claims, and the alkyl group represented by “e” is one carbon shorter in Baryza, paragraph 0746 as compared with the instantly claimed structure. Nevertheless, a prima facie case of obviousness may be made when chemical compounds have very close structural similarities and similar utilities. An obviousness rejection based on similarity in chemical structure and function entails the motivation of one skilled in the art to make a claimed compound, in the expectation that compounds similar in structure will have similar properties. See MPEP 2144.09, especially MPEP 2144.09(I). In this case, both the structure of Baryza and the instantly claimed structure are used as ionizable cationic lipids in lipid nanoparticles for delivering RNA. As such, differences in carbon chain lengths would have been close structural similarity, and the particles of these different chain lengths would have been expected to have been useful in forming lipid nanoparticles for delivery of RNA. Also, while the majority of examples of Baryza teach 1,3,5 substitution around the benzene ring, Baryza also suggests other substitution patterns as of at least the structure on paragraph 1061; as such, the skilled artisan would have been motivated to have optimized the substitution pattern around the benzene ring. As to claim 10, this claim is rejected for essentially the same reason that claim 9 is rejected. As to claim 15, Baryza teaches siRNA and mRNA in paragraph 0013; these are understood to read on the required therapeutic agent. As to claim 16, Baryza teaches siRNA and mRNA in paragraph 0013; these are understood to read on the required nucleic acid. As to claim 17, Baryza teaches siRNA and mRNA in paragraph 0013; these are understood to read on the requirements of claim 17. As to claim 18, Baryza teaches self-replicating mRNA in paragraph 0418. As to claim 19, Baryza teaches a formulation comprising I), a helper lipid, for example cholesterol, a neutral lipid, for example DSPC, and a stealth lipid, for example PEG-DMG in paragraph 0302. As to claim 20, Baryza teaches the following in paragraph 0303, reproduced below. PNG media_image5.png 350 504 media_image5.png Greyscale Baryza also teaches adjusting the ratios of the different lipids, as of paragraph 0308. As such, the skilled artisan would have been motivated to have optimized the ratios of the different lipids in the nanoparticle of Baryza to have achieved the claimed ratio. Optimization of a result-effective variable is prima facie obvious; see MPEP 2144.05(II)(B). In this case, the teachings of paragraph 0308 of Baryza would appear to indicate that the amounts of various lipids is a result-effective variable. As to claims 32-33, Baryza teaches DSPC and DOPE in paragraph 0276. Baryza teaches cholesterol as a helper lipid in paragraph 0301. Baryza teaches cholesterol, DSPC and PEG-DMG in paragraph 1502. Baryza suggests formulating the molecular weight of PEG to be about 2000 Daltons in paragraph 0296. As to claim 34, this claim is rejected for the same reason that claims 9-10 are rejected. Response to Arguments Regarding Prior Art Rejections Applicant has presented various arguments regarding the previously applied prior art rejection, as of applicant’s response on 26 May 2026 (hereafter referred to as applicant’s response). These arguments are addressed below. Applicant argues that the proposed combination is based upon hindsight reasoning, as of applicant’s arguments, page 15. This is not persuasive. Applicants may argue that the examiner’s conclusion of obviousness is based on improper hindsight reasoning. However, any judgment on obviousness is in a sense necessarily a reconstruction based on hindsight reasoning, but so long as it takes into account only knowledge which was within the level of ordinary skill in the art at the time the claimed invention was made and does not include knowledge gleaned only from applicant’s disclosure, such a reconstruction is proper. See MPEP 2145(X)(A). In this case, applicant has not pointed to the examiner using knowledge gleaned only from applicant’s disclosure in setting forth the applied rejection. As such, applicant’s arguments based upon hindsight reasoning are not persuasive. Applicant argues that structure-activity relationships with respect to ionizable lipids for nucleic acid delivery are highly unpredictable, as of applicant’s response, page 15. In a similar vein, applicant makes the following argument, as of page 16, top paragraph, relevant text reproduced below. PNG media_image6.png 130 790 media_image6.png Greyscale In order to further explain the state of the art regarding this issue, the examiner cites Lowe (https://www.science.org/content/blog-post/rna-vaccines-and-their-lipids accessed 19 October 2022, originally published 11 January 2021, 15 printed pages). Lowe teaches the following on page 3, last paragraph, about the lipid formulations used to deliver mRNA in the COVID-19 mRNA vaccines, wherein relevant text has been reproduced below. PNG media_image7.png 402 1600 media_image7.png Greyscale Lowe further teaches the following on page 4, second paragraph, relevant text reproduced below. PNG media_image8.png 322 1594 media_image8.png Greyscale As such, in view of the teachings of Lowe the examiner does not dispute the general idea that different lipids and different formulations would have had different levels of effectiveness. With that being said, the examiner notes that a case of obviousness requires a reasonable expectation of success, not absolute predictability. See MPEP 2143.02, especially MPEP 2143.02(II). The skilled artisan would have had a reasonable (but not absolute) expectation that a particular ionizable cationic lipid, when used in a lipid nanoparticle such as that described by Baryza and/or Beckwith (as well as of that of Lowe) would have successfully delivered an RNA payload. The examiner further notes that even if, purely en arguendo, the teachings of Lowe are interpreted as teaching that the lipids relied upon by the examiner in the applied rejection are not the best lipids (and the examiner does not concede that Lowe actually teaches this), that would still not be sufficient to overcome the applied rejection. A known or obvious composition does not become patentable simply because it has been described as somewhat inferior to some other product for the same use. See MPEP 2145(X)(D)(1), first paragraph in section. Additionally, the prior art’s mere disclosure of more than one alternative does not constitute a teaching away from any of these alternatives because such disclosure does not criticize, discredit, or otherwise discourage the solution claimed. See MPEP 2145(X)(D)(1), second paragraph in section. Statements in both applicant’s arguments and in Lowe attesting to the fact that different lipids would have had different levels of effectiveness are not teaching away from the combination proposed by the examiner. The examiner clarifies that Lowe is not part of the statement of rejection. In contrast, Lowe is newly cited by the examiner in an attempt to best evaluate applicant’s arguments and to best place applicant’s arguments into their appropriate context. Applicant argues that the combination proposed by the examiner of Baryza was not actually made or tested by Baryza, as of applicant’s response, page 15, bottom paragraph. In response, the examiner takes the position that for this reason, the claims are not rejected as anticipated by Baryza. Nevertheless, the skilled artisan would have been motivated to have made the proposed combination and would have had a reasonable expectation of forming an ionizable cationic lipid capable of successfully delivering nucleic acid when formed in a lipid nanoparticle. This is sufficient to result in a prima facie case of obviousness. Applicant then makes the following argument on page 16, relevant text reproduced below. PNG media_image9.png 202 786 media_image9.png Greyscale Applicant’s argument that the prior art fails to teach the claimed ester orientation is not correct. Baryza teaches the required ester orientation in the long alkyl chains in the structure below. PNG media_image1.png 272 810 media_image1.png Greyscale While the compounds of Beckwith have a different orientation of the ester groups, this is insufficient to overcome the applied rejection. This is because applicant’s arguments appear to point to the teachings of Beckwith by itself rather than the combination of references. Such arguments are not persuasive. One cannot show non-obviousness by attacking references individually where the rejections are based on combinations of references. See MPEP 2145(IV). Applicant argues that the examiner has not provided a reason as to why the skilled artisan would have reversed the ester orientation (as compared with the ester orientation taught by Beckwith). In response, the examiner notes that the “reversed” ester orientation (i.e. the ester orientation that is reversed compared with what is taught by Beckwith but reads on the claims) has been taught by Baryza. Applicant then makes the following argument. PNG media_image10.png 102 786 media_image10.png Greyscale Even if, purely en arguendo, the above-reproduced statement is correct, it is insufficient to overcome the applied rejection. Nothing in the prior art indicates that a particular ester orientation would have resulted in a lipid having an electron density or hydrolytic stability that would have been unsuitable for delivery of a nucleic acid. Additionally, nothing in the prior art indicates that a particular ester orientation would have resulted in the formation of lipid nanoparticles that would have failed to have delivered active agent. As such, the above-reproduced argument does not meet the burden of showing that the prior art teaches away from the claimed invention. See the discussion above regarding MPEP 2145(X)(D)(1) and 2145(X)(D)(2) regarding the issues of teaching away. Applicant’s arguments regarding Strodiot et al. (WO 2018/220553 A1) have not been addressed substantively here because the instant claims are not rejection over Strodiot. Strodiot is discussed below. Applicant then makes the following argument, as of page 16, relevant text reproduced below. PNG media_image11.png 138 780 media_image11.png Greyscale This is not persuasive. To the extent that applicant is arguing that there are unexpected improvements associated with compounds I, II, and III, this is not persuasive. The burden is on applicant to establish that results are unexpected and significant. See MPEP 716.02(b)(I). Applicants have the burden of explaining data which is proffered as evidence of non-obviousness. See MPEP 716.02(b)(II). The above-reproduced statement does not meet the burden on applicant set forth in MPEP 716.02(b). Claims 11-12 Are Not Rejected Over Prior Art Claims 11-12 are not rejected over prior art. As relevant prior art, the examiner cites Baryza et al. (US 2018/0369386 A1), which was cited in the obviousness rejection above. The teachings of Baryza are insufficient to render claims 11-12 prima facie obvious at least because Baryza does not teach the combination of a molecule comprising a) a carbonyl group between the benzene ring and the amine (L5), two phenolic oxygen atoms on the carbon chains lacking the amine (i.e. L2 and L3), a 1,2,5 substitution pattern around the ring (wherein the “1” refers to the chain with the amine), ester groups between the phenolic oxygen and the end of the carbon chains in which the carbonyl carbon faces the benzene ring (i.e. L1 and L4), as well as an asymmetric molecule wherein one functional group of R1-3 splits into two chains whereas the other functional group of R8-10 remains a single chain. There would have been no motivation for the skilled artisan to have picked and chosen different features in Baryza to have achieved the structures recited by claims 11-12. As an additional relevant prior art reference, the examiner cites Strodiot et al. (WO 2018/220553 A1). Strodiot et al. (hereafter referred to as Strodiot) is drawn to a liposome encapsulated RNA and a method of making such a liposome, as of Strodiot, title and abstract. Strodiot teaches the following lipid, as of page 25, relevant structure reproduced below. PNG media_image12.png 150 338 media_image12.png Greyscale Strodiot also teaches the following lipid, as of page 26, relevant structure reproduced below. PNG media_image13.png 178 344 media_image13.png Greyscale These structures differ from the claimed invention at least in the same manner that the structures of Baryza differ from the claimed invention. Structure RV84 also has an ester orientation with the ester oxygen closest to the benzene ring; this is opposite what is required by the instant claims. As such, instant claims 11-12 have not been rejected as obvious over Strodiot for essentially the same reason that these claims have not been rejected as obvious over Baryza. As additional relevant prior art, the examiner cites Beckwith et al. (US 2017/0275243 A1), over which the claims are rejected above. One relevant structure taught by Beckwith is the following from page 59, paragraph 0558, which is reproduced below with annotation by the examiner. PNG media_image14.png 360 549 media_image14.png Greyscale The above-reproduced structure differs from the structures of claims 11-12. This is because a) the above-reproduced structure does not teach the required L1 and L4 because in the above-reproduced structure, the oxygen faces the benzene ring, whereas the claims require carbon atoms facing the benzene ring, b) the above-reproduced structure teaches various ether oxygen atoms not recited by the claims, and c) the above-reproduced structure is not an asymmetric molecule wherein one functional group of R1-3 splits into two chains whereas the other functional group of R8-10 remains a single chain. In view of this, instant claims 11-12 have not been rejected over Beckwith. The examiner clarifies that claims 11-12 are not allowable because they remain subject to non-prior art rejections. Non-Statutory Double Patenting The nonstatutory double patenting rejection is based on a judicially created doctrine grounded in public policy (a policy reflected in the statute) so as to prevent the unjustified or improper timewise extension of the “right to exclude” granted by a patent and to prevent possible harassment by multiple assignees. A nonstatutory double patenting rejection is appropriate where the conflicting claims are not identical, but at least one examined application claim is not patentably distinct from the reference claim(s) because the examined application claim is either anticipated by, or would have been obvious over, the reference claim(s). See, e.g., In re Berg, 140 F.3d 1428, 46 USPQ2d 1226 (Fed. Cir. 1998); In re Goodman, 11 F.3d 1046, 29 USPQ2d 2010 (Fed. Cir. 1993); In re Longi, 759 F.2d 887, 225 USPQ 645 (Fed. Cir. 1985); In re Van Ornum, 686 F.2d 937, 214 USPQ 761 (CCPA 1982); In re Vogel, 422 F.2d 438, 164 USPQ 619 (CCPA 1970); In re Thorington, 418 F.2d 528, 163 USPQ 644 (CCPA 1969). A timely filed terminal disclaimer in compliance with 37 CFR 1.321(c) or 1.321(d) may be used to overcome an actual or provisional rejection based on nonstatutory double patenting provided the reference application or patent either is shown to be commonly owned with the examined application, or claims an invention made as a result of activities undertaken within the scope of a joint research agreement. See MPEP § 717.02 for applications subject to examination under the first inventor to file provisions of the AIA as explained in MPEP § 2159. See MPEP § 2146 et seq. for applications not subject to examination under the first inventor to file provisions of the AIA . A terminal disclaimer must be signed in compliance with 37 CFR 1.321(b). The filing of a terminal disclaimer by itself is not a complete reply to a nonstatutory double patenting (NSDP) rejection. A complete reply requires that the terminal disclaimer be accompanied by a reply requesting reconsideration of the prior Office action. Even where the NSDP rejection is provisional the reply must be complete. See MPEP § 804, subsection I.B.1. For a reply to a non-final Office action, see 37 CFR 1.111(a). For a reply to final Office action, see 37 CFR 1.113(c). A request for reconsideration while not provided for in 37 CFR 1.113(c) may be filed after final for consideration. See MPEP §§ 706.07(e) and 714.13. The USPTO Internet website contains terminal disclaimer forms which may be used. Please visit www.uspto.gov/patent/patents-forms. The actual filing date of the application in which the form is filed determines what form (e.g., PTO/SB/25, PTO/SB/26, PTO/AIA /25, or PTO/AIA /26) should be used. A web-based eTerminal Disclaimer may be filled out completely online using web-screens. An eTerminal Disclaimer that meets all requirements is auto-processed and approved immediately upon submission. For more information about eTerminal Disclaimers, refer to www.uspto.gov/patents/apply/applying-online/eterminal-disclaimer. Claims 1, 4-7, 9-12, 15-20 and 32-34 are provisionally rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1, 5-6, 19, 30-31, 34, 47, 53, 63, 72, 76, 86, 93, 112, 117, and 123-126 of copending Application No. 18/667,934 (reference application). Although the claims at issue are not identical, they are not patentably distinct from each other because of the following reasons: The instant claims are drawn to an ionizable lipid with a particular chemical structure. The copending claims recite an ionizable lipid with the following chemical structures, as of copending claim 76, relevant structures reproduced below. PNG media_image15.png 392 558 media_image15.png Greyscale The instant claims and copending claims differ because the copending claims include various claims drawn to a self-replicating RNA vector, which are not recited by the instant claims. Nevertheless, the above-reproduced chemical structures from the copending claims appear to be within the scope of the structures recited by the instant claims. Thereby the structures from the copending claims effectively anticipate the instant claims, thereby resulting in a prima facie case of anticipatory-type non-statutory double patenting. This is a provisional nonstatutory double patenting rejection because the patentably indistinct claims have not in fact been patented. Claims 1, 4-7, 9-11, 15-20 and 32-34 are provisionally rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1-2, 5, 8, 13, 15, 21-23, 28-29, 35, 39, 42-43, 45-46, and 80-82 of copending Application No. 18/667,939 (reference application). Although the claims at issue are not identical, they are not patentably distinct from each other because of the following reasons: The instant claims are drawn to an ionizable lipid with a particular chemical structure. The copending claims recite an ionizable lipid with the following chemical structures, as of copending claim 1, relevant structure reproduced below. PNG media_image16.png 174 652 media_image16.png Greyscale The instant claims and copending claims differ because the copending claims include various claims drawn to a self-replicating RNA vector, which are not recited by the instant claims. Nevertheless, the above-reproduced chemical structures from the copending claims appear to be within the scope of the structures recited by the instant claims. Thereby the structures from the copending claims effectively anticipate the instant claims, thereby resulting in a prima facie case of anticipatory-type non-statutory double patenting. This is a provisional nonstatutory double patenting rejection because the patentably indistinct claims have not in fact been patented. Claims 1, 4-7, 9-12, 15-20 and 32-34 are provisionally rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1-2, 4, 8, 10, 12-13, 16, 19, 22-23, 27-33, 36, and 42 of copending Application No. 19/231,051 (reference application). Although the claims at issue are not identical, they are not patentably distinct from each other because of the following reasons: The instant claims are drawn to an ionizable lipid with a particular chemical structure. The copending claims recite an ionizable lipid with the following chemical structures, as of copending claim 30, relevant structures reproduced below. PNG media_image17.png 546 554 media_image17.png Greyscale The instant claims and copending claims differ because the copending claims include various claims drawn to a self-replicating RNA vector, which are not recited by the instant claims. Nevertheless, the above-reproduced chemical structures from the copending claims appear to be within the scope of the structures recited by the instant claims. Thereby the structures from the copending claims effectively anticipate the instant claims, thereby resulting in a prima facie case of anticipatory-type non-statutory double patenting. This is a provisional nonstatutory double patenting rejection because the patentably indistinct claims have not in fact been patented. Response to Arguments Regarding Double Patenting Rejections In applicant’s response on 26 May 2026, applicant has requested that the double patenting rejections be held in abeyance. As such, the previously applied double patenting rejections have been maintained by the examiner. Conclusion No claim is allowed. 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. Any inquiry concerning this communication or earlier communications from the examiner should be directed to ISAAC SHOMER whose telephone number is (571)270-7671. The examiner can normally be reached 7:30 AM to 5:00 PM Monday Through Friday. Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice. If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Sahana Kaup can be reached at (571)272-6897. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300. Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000. ISAAC . SHOMER Primary Examiner Art Unit 1612 /ISAAC SHOMER/ Primary Examiner, Art Unit 1612
Read full office action

Prosecution Timeline

Aug 02, 2023
Application Filed
Feb 23, 2026
Non-Final Rejection mailed — §103, §DP
May 26, 2026
Response Filed
Jun 25, 2026
Final Rejection mailed — §103, §DP (current)

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Patent 12636352
Functionalized Enzyme-Powered Nanomotors
4y 11m to grant Granted May 26, 2026
Patent 12611419
LIPOSOMAL COMPOSITION FOR USE IN A METHOD OF TREATING PARKINSON'S DISEASE
3y 1m to grant Granted Apr 28, 2026
Study what changed to get past this examiner. Based on 5 most recent grants.

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Prosecution Projections

3-4
Expected OA Rounds
63%
Grant Probability
94%
With Interview (+30.3%)
2y 11m (~0m remaining)
Median Time to Grant
Moderate
PTA Risk
Based on 1190 resolved cases by this examiner. Grant probability derived from career allowance rate.

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