DETAILED ACTION
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
This office action is directed at claims filed 12/17/2024.
Claims 1-20 are pending.
The instant application claims priority as a continuation in part of U.S. application 18/275,591 filed 8/2/2023, now U.S. patent 12,180,481, under 37 CFR to PCT/US22/14958 filed 2/2/2022 which claims the benefit of U.S. Provisional Application Serial No. 63/144,827, filed February 2, 2021, and U.S. Provisional Application Serial No. 63/184,011, filed May 4, 2021.
Information Disclosure Statement
An IDS filed 11/15/2024 has been identified and the documents considered. The signed and initialed PTO Form 1449 has been mailed with this action. The document listed as a Search reports has been considered but have been crossed off of the Form 1449.
Claim Objections
Claim 20 is objected to because of the following informalities: in vivo, in vitro, ex vivo should be italicized.
Appropriate correction is required.
Claim Rejections - 35 USC § 112, second paragraph
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claim 8 recites the limitation "the heterologous membrane surface ligand" in line 14. There is insufficient antecedent basis for this limitation in the claim. Claim 14 does not so reference a ligand.
Claim 19 recites the limitation "The method" in line 1. There is insufficient antecedent basis for this limitation in the claim. Claims should initiate with the article “A”.
Claim Rejections - 35 USC § 112, first paragraph
The following is a quotation of the first paragraph of 35 U.S.C. 112:
The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same and shall set forth the best mode contemplated by the inventor of carrying out his invention.
Claims 1-20 are rejected under 35 U.S.C. 112, first paragraph, because the specification, while being enabling for administering Saccharomyces boulardii extracellular vesicles comprising expression cassettes encoding shRNA targeting Nsp1 gene from SARS-COV-2 genome integrated in YPRCt3 locus on XVI chromosome under control of an RNA polymerase II promoter to a subject infected with SARS-COV-2, does not reasonably provide enablement for any other embodiment. The specification does not enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the invention commensurate in scope with these claims.
The test of enablement is whether one skilled in the art could make and use the claimed invention from the disclosures in the patent coupled with information known in the art without undue experimentation (United States v. Telectronics, Inc., 8 USPQ2d 1217 (Fed. Cir. 1988)). Whether undue experimentation is required is not based on a single factor but is rather a conclusion reached by weighing many factors (See Ex parte Forman, 230 USPQ 546 (Bd. Pat. App. & Inter, 1986) and In re Wands, 8USPQ2d 1400 (Fed. Cir. 1988); these factors include the following:
1) Nature of invention. The instant claims are drawn to a method of using extracellular vesicles (EVs) to deliver heterologous RNAs to a target cell. The cell is in vivo or in vitro and is used to treat infection or disease or conditions. In some claims the RNA inhibits expression of a pathogen gene or endogenous gene expression.
2) Scope of the invention. The scope of the invention is extremely broad in that in all cases of claim 1 (treating an infection), claim 14 (treating a disease or condition) and claim 19 (delivering a nucleic acid to a target cell), the EV contains any heterologous nucleic acid and the target is simply any even if to treat an infection or disease or condition, the base claims do not limit this condition or infection. Secondly, in all cases, the method simply r3eqwuires administering (claim 1 and 14) or contacting (claim 19). In claim 1, the claim is directed to inhibit the expression of any pathogen gene or endogens gene in a subject. The implication appears that the infection is caused by either of these. However, the genes are extremely broad as recited. In claim 14, the disease or condition is an unlimited diverse array of conditions and in claim 19 there is no target or outcome.
3) Number of working examples and guidance. The disclosure teaches isolation and characterization of Saccharomyces-boulardii EVs. Because Sb does not have RNAi machinery, expression cassettes expression shRNA under RNA polymerase II type TDH3 promoter or under control of RNA polymerase I rRNA promoter and the only example provided was,
Expression cassettes used in this work contained two short hairpin RNA (shRNA), one targeting Nsp1 gene from SARS-COV-2 genome (SEQ ID NO. 1, and 18), and second targeting eGFP gene (SEQ ID NO. 1, and 18). ShRNA expression cassettes were genome integrated in YPRCt3 locus on XVI chromosome. It was previously shown that integration at this locus does not affect the cell growth and gene expression in S. boulardii (Durmusoglu et al, 2020)
Inhibition was assayed on cells in vitro and
After 4 days of co-cultivation, the present inventors extracted RNA from H1299 cells and performed qPCR with primers to nspl gene to measure the nspl expression level. As shown in FIG. 7, the H1299 cells grown in the presence of both Sb strains expressing shRNA targeting nspl gene under control of pol I or pol II promoters the level of nsp1 expression was significantly lower (30% reduction for pol I-driven, and 52% reduction for pol II-driven siRNA expression) compared to the cells co-cultivated with wt Sb, though this effect was more prominent in cells co-cultivated with Sb-pol-II-siNsp1-siGFP strain.
4) State of the art. Saccharomyces boulardii is a nonpathogenic yeast prescribed for treatment of diarrhea and other gastrointestinal diseases as a probiotic (see Kelesidis and Pothoulakis, Therapeutic Advances in Gastroenterology, 22012, pages 111-125). However, it s use as a source of exosomes is nascent. This is reviewed by Mierzejewska et al (Int. J. Mol. Sci. 2023, pages 1-15).
The research was divided into three main tasks: (1) isolation and morphological and proteomic characterization of EVs from yeast cultures; (2) study of changes in the metabolic activity of model human intestinal cell lines in the presence of yeast EVs; and (3) investigation of whether EVs are able to effectively transfer their cargo to human cells.
The results were promising but have not extended beyond cell culture.
This research has also shown that the tested vesicles are clearly not cytotoxic for three model human intestinal cell lines. In addition, yeast EVs are able to internalize in vitro with human cells and transfer their cargo. Moreover, the detailed proteomic analysis of these particles might be helpful for modifying the protein composition of yeast EVs so that they contain not only biologically active molecules but also receptor proteins that recognize, for example, cancer cells in colon tissues. This could lead to the specific transport of loaded biologically active substances to selected cells and tissues in the body. Taking all of the above into account, the final conclusion of the study is that probiotic yeast EVs are promising candidates as carriers of biologically active substances
As to attempts to target SARS-COV2, Guo et al teach EVs that comprise inhibitory RNA against SARS-COV2 such as siRNA (see abstract, page 3, lines 24-29, and figure 28).
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Guo does not teach that the EV are generated from Saccharomyces. However, EV from Saccharomyces were well known in the art. Polach et al teach methods of constructing and using EV from Saccharomyces cerevisiae comprising biologically active RNA molecules to treat diseases and disorders (see abstract and ¶0021). The system provides a solution to a problem of loading biologically active molecules in abundance for use in vivo (see ¶0085). The vesicles are secreted from yeast cells and accumulate in the growth media in high production scale wherein RNA is easily loaded or transcribed in the vesicle (see ¶0094, 0097, 0098).
5) Unpredictability of the art. The claimed methods are not supported with sufficient guidance such that a person of skill in the art could perform the method. As a first issue, the target is so broad that identifying the subject or target would require undue experimentation. It would require identifying the disease or infection or condition and thereafter the nucleic acid to administer. In claim 19, the use is unknown. The only disclosed targets and outcomes disclosed in the disclosure is nsp1 inhibition to target SARS-COV-2 infection wherein the EV is more particularly designed with integrated expression cassettes.
The broadly claimed invention to the contrary does not overcome obstacles so noted in the art. These are summarized by Nunes et al (Molecular Therapy, 2025, pages 2243-
Despite the encouraging application of EVs as a therapeutic tool for delivering nuclei acids, several challenges still remain. These challenges include identifying the right donor cells for EV production, developing a more efficient method to load therapeutic nucleic acid into EVs, and improving the targeting of the EVs. 49 Advances in overcoming these challenges will help to facilitate safe clinical ap plications of nucleic acid-EVs.
However, several challenges still exist that need to be addressed for the widespread clinical use of EVs. The first is the rapid clearance of EVs after intravenous injection, mostly due to engulfment by macrophages and other cell types. The second is the need to limit the off-target effects of EVs. Although progress has been made at increasing the targeting EVs to certain cell types, it has been difficult to prevent the off-target uptake of EVs. Third, the composition of EVs is complex, making the production and quality control of vesicles difficult to reproduce. Reproducible, scalable engineering and production strategies are needed as well as scalable EV isolation protocols, which also include procedures for storage of EVs. Also, despite the engineering of EVs to carry a therapeutic agent(s), the many endogenous components within EVs from a specific cell type could have unwanted effects. In addition, when loaded with drugs or nucleic acids through passive methods, the molecular composition of donor cells and EVs changes. This also may be true for active loading approaches.
Loading the EV as generically claimed has not been easy to accomplish. The instant claims are engineered EVs and Xu teaches
Engineered EVs can somewhat overcome the limitations of natural EVs, such as drug loading and targeted delivery. However, engineering EVs also faces many challenges. The efficacy vs. safety trade-off in EV engineering is a critical consideration for therapeutic applications. While engineering can enhance EV functionality (e.g., drug delivery, targeting, or immunomodulation), it may also introduce risks such as toxicity, immunogenicity, or unintended biodistribution9,228. Endogenous loading (via parental cell modification) has relatively stable but low loading efficiency and is associated with a risk of unintended cargo alterations224,229. Exogenous loading (postisolation modification) suffers from payload leakage and requires extensive postpurification to remove unencapsulated molecules230. Moreover, chemical and physical modification processes can induce structural deformations (15% to 30% vesicle collapse rate) and impair biological activity by denaturing surface proteins224,229. The membrane damage caused by electroporation/sonication may lead to EV clearance by the mononuclear phagocyte system, and residual transfection reagents (e.g., lipofectamine) can cause cytotoxicity.
Furthermore, direct loading of sdiRNA has found to lead to aggregation and precipitation (see Xu et al, Signal Transduction and Targeted Therapy (2025) pages 1-26 especially page 5 and 13).
Finally, claim 7 refers to combinations of the anchor proteins recited above. At issue is these are compounds recited in terms of partial structures wherein the partial structures are invoked to perform a function of creating an EV with the ability link the ligand to the lipid bilayer. However, the disclosure is not drawn to any combinations nor does the art provide combinations of these components that can be used to anchor the ligand. Claim 14 refers to polynucleotides “configured to treat the disease or condition”. However, the only configuration taught is siRNA encoding nspI to treat SARS. To this end, the MPEP provides such guidance (emphasis added). If the application as filed does not disclose the complete structure (or acts of a process) of the claimed invention as a whole, determine whether the specification discloses other relevant identifying characteristics sufficient to describe the claimed invention in such full, clear, concise, and exact terms that a skilled artisan would recognize applicant was in possession of the claimed invention. For example, if the art has established a strong correlation between structure and function, one skilled in the art would be able to predict with a reasonable degree of confidence the structure of the claimed invention from a recitation of its function. Thus, the written description requirement may be satisfied through disclosure of function and minimal structure when there is a well-established correlation between structure and function. In contrast, without such a correlation, the capability to recognize or understand the structure from the mere recitation of function and minimal structure is highly unlikely. In this latter case, disclosure of function alone is little more than a wish for possession; it does not satisfy the written description requirement. See Eli Lilly, 119 F.3d at 1568, 43 USPQ2d at 1406 (written description requirement not satisfied by merely providing "a result that one might achieve if one made that invention"); In re Wilder, 736 F.2d 1516, 1521, 222 USPQ 369, 372-73 (Fed. Cir. 1984) (affirming a rejection for lack of written description because the specification does "little more than outline goals appellants hope the claimed invention achieves and the problems the invention will hopefully ameliorate"). Compare Fonar, 107 F.3d at 1549, 41 USPQ2d at 1805 (disclosure of software function adequate in that art).
6) Undue experimentation. The claims have been evaluated in light of the art at the time of filing and found not to be commensurate in scope with the specification. MPEP 2164.05 teaches, “However, the examiner should carefully compare the steps, materials, and conditions used in the experiments of the declaration with those disclosed in the application to make sure that they are commensurate in scope; i.e., that the experiments used the guidance in the specification as filed and what was well known to one of skill in the art. Such a showing also must be commensurate with the scope of the claimed invention, i.e., must bear a reasonable correlation to the scope of the claimed invention. The invention recites use of a broad group of sequence. Given the unpredictability of the art, the poorly developed state of the art with regard to predicting the structural/ functional characteristics of antagonists, the lack of adequate working examples and the lack of guidance provided by applicants, the skilled artisan would have to have conducted undue, unpredictable experimentation to practice the claimed invention.”
Double Patenting
A rejection based on double patenting of the "same invention" type finds its support in the language of 35 U.S.C. 101 which states that "whoever invents or discovers any new and useful process ... may obtain a patent therefor ..." (Emphasis added). Thus, the term "same invention," in this context, means an invention drawn to identical subject matter. See Miller v. Eagle Mfg. Co., 151 U.S. 186 (1894); In re Ockert, 245 F.2d 467, 114 USPQ 330 (CCPA 1957); and In re Vogel, 422 F.2d 438, 164 USPQ 619 (CCPA 1970).
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. See 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);and, 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) may be used to overcome an actual or provisional rejection based on a nonstatutory double patenting ground provided the conflicting application or patent is shown to be commonly owned with this application. See 37 CFR 1.130(b).
Effective January 1, 1994, a registered attorney or agent of record may sign a terminal disclaimer. A terminal disclaimer signed by the assignee must fully comply with 37 CFR 3.73(b).
Claims 1-20 are provisionally rejected under the judicially created doctrine of obviousness-type double patenting as being unpatentable over claims 1 ,2, 4-9 and 11-16 of U.S. Patent 12,180,481. The safe harbor for non-statutory double patenting only applies for applications filed as divisional applications. The instant application is a CIP of the copending U.S, serial 18/275,591 now U.S. Patent 12,180,481.
An obviousness-type double patenting rejection is appropriate where the conflicting claims are not identical, but an examined application claim is not patentably distinct from the reference claims because the examined claim is either anticipated by, or would have been obvious over, the reference claims. Although the conflicting claims are not identical, they are not patentably distinct from each other because the cited claims of the instant invention are generic to all that is recited in claims 1 ,2, 4-9 and 11-16 of U.S. Patent 12,180,481. That is, the cited claims of U.S. Patent 12,180,481 anticipate and fall entirely within the scope of the rejected claims of the instant application. Specifically, application U.S. Patent 12,180,481 is drawn to products used in the methods of the instant claims. The EV recited in the copending claims overlap by referencing heterologous RNAs that include the dsRNA, miRNA and siRNA of the instant claims. As well, the target of the SARS-COV-2 is found in both claims as are the surface ligands and anchor proteins. Missing from the instant claims is the explicit recitation of SEQ ID NO:18 representing an siRNA.
Additionally, if a patent resulting from the instant claims was issued and transferred to an assignee different from the assignee holding the U.S. Patent 12,180,481, then two different assignees would hold a patent to the claimed invention of U.S. Patent 12,180,481, and thus improperly there would be possible harassment by multiple assignees.
Conclusion
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/MARIA MARVICH/Primary Examiner, Art Unit 1631
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