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 .
DETAILED ACTION
The text of those sections of Title 35, U.S. Code not included in this action can be found
in a prior Office action.
This Action is in response to the papers filed on November 13, 2025 for a Request for Continued Examination. 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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 November 13, 2025 has been entered.
Pursuant to the amendment filed on November 11, 2025, claims 2-5, 9-10 and 15 are currently pending. Claim 15 has been amended and claims 6-8 and 17-19 have been cancelled in addition to previously withdrawn claims 1, 11, 20-26 have been canceled in Applicant’s Amendments filed on November 13, 2025.
The previous Office Action filed on May 14, 2025 has made notice of Allowable Subject Matter, specifically SEQ ID NO: 3 as there were no sequences that were 100% identical to the sequence when using sequence search tools. After continued examination, the Examiner has learned of prior art that makes obvious this sequence, and therefore is no longer any allowable subject matter after the new round of examination. Please refer to the new ground of rejection listed below for claim 15.
Therefore, claims 2-5, 9-10, and 15 are currently under examination to which the following grounds of rejection are applicable.
Response to Arguments
Withdrawn Objections/Rejections in response to Applicants’ arguments or amendments:
Drawings
In view of Applicants’ amendment to the Drawings received on November 10, 2025, the objections to the Drawings have been withdrawn.
Claim Rejections - 35 USC § 112(a)
In view of Applicants’ amendment to the claims dated November 10, 2025, wherein claims 17-19 have been cancelled, the rejection to claims 17-19 rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, have been rendered moot.
Claim Rejections - 35 USC § 112(b)
In view of Applicants’ amendment to the claims dated November 10, 2025, wherein claim 15 has been amended and claim 17 has been cancelled, the rejection to claims 2-10, 15, 17-19 rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite, have been withdrawn.
Claim Rejections - 35 USC § 103
In view of Applicants’ amendment to the claims dated November 10, 2025, wherein claim 15 has been amended and claims 6-8 and 17-19 have been cancelled, the rejection to claims 2, 5, 9, and 15 rejected under 35 U.S.C. 103 as being unpatentable over Biffi further in view of Krawetz are withdrawn. The rejection to now cancelled claims 6-7 have been rendered moot.
In view of Applicants’ amendment to the claims dated November 10, 2025, wherein claim 15 has been amended and claims 6-8 and 17-19 have been cancelled, the rejection to claims 3-4 rejected under 35 U.S.C. 103 as being unpatentable over Biffi further in view of Krawetz as applied to claim 15, and further in view of Malik are withdrawn.
In view of Applicants’ amendment to the claims dated November 10, 2025, wherein claim 15 has been amended and claims 6-8 and 17-19 have been cancelled, the rejection to claims 9, 10 and 15 rejected under 35 U.S.C. 103 as being unpatentable over Biffi further in view of Krawetz as applied to claim 15, and further in view of Oshikawa is withdrawn.
The withdrawn rejections are in view of the amendment to claim 15 now reciting, “wherein the LV comprises a modified Woodchuck Posttranscriptional Regulatory Element having a nucleic acid sequence as set forth in SEO ID NO: 3,” because the prior art references do not teach this specific WPRE sequence.
Applicants’ arguments are moot in view of the withdrawn rejection. A response to any argument pertaining to a new or maintained rejection can be found below.
New Grounds of Rejection:
Claim Rejections - 35 USC § 103
Claims 2, 5, 9, and 15 are rejected under 35 U.S.C. 103 as being unpatentable over Biffi et al. (Science 341, 1233158 (2013); of record IDS filed on February 21, 2023; hereinafter ‘Biffi’) in view of Krawetz et al. (Tissue Engineering Part C: Methods 16.4 (2010): 573-582; hereinafter ‘Krawetz’; of record) and Zanta-Boussif et al. (Gene Therapy 16.5 (2009): 605-619; of record IDS filed on February 21, 2023; hereinafter ‘Zanta-Boussif’) as evidenced by STIC Sequence Search for SEQ ID NO:3; of record). The STIC Sequence Search has been supplied in the Office Action dated May 15, 2025.
Claim 15 is directed to a method of maintaining the multipotency for LV infection of a t-hematopoietic stem cell transduced with a recombinant lentiviral vector (LV) comprising: an arylsulfatase A (ARSA) gene encoding an arylsulfatase A polypeptide, where said LV is a self-inactivating (SIN) lentiviral vector wherein the LV comprises a modified Woodchuck Posttranscriptional Regulatory Element having a nucleic acid sequence as set forth in SEO ID NO: 3, in a media comprising thrombopoietin (TPO), stem cell factor (SCF), PMS-like tyrosine kinase-3 (FLT3), and Interleukin 3 (IL-3) factors, and wherein the media further comprises kinase inhibitors that inhibit mammalian target of rapamycin (mTOR) and Rho associated protein kinase (ROCK) activity.
Regarding claim 15, Biffi teaches CD34+ cells/ hematopoietic stem cells (HSCs) that are isolated from a patient which were then placed in culture media containing interleukin-3 (IL-3), thrombopoietin (TPO), stem cell factor (SCF), and Flt3 ligand, and the cells were then transduced with a self-inactivating lentiviral vector comprising the ARSA gene ((p 9, col 1), “The vector used in this study (pCCLsin.cPPT.hPGK.hARSA.WPREmut6 - PGK.ARSA.LV) is a self-inactivating lentiviral vector produced with a third-generation split packaging system”; p 8, col 2-3); HSC gene marking in vivo revealed evidence of self-renewal and multilineage potential of the transduced engrafted HSCs suggesting maintenance of multipotent potential (p 5, col 2- p 6, col 1).
Biffi does not teach any kinase inhibitors with the transduced HSCs, more specifically kinase inhibitors that inhibit mTOR and ROCK activity, and furthermore the vector employing the same WPRE comprised in SEQ ID NO: 3.
Krawetz teaches that ROCK inhibitors (ROCKi) increase the survival of dissociated, single human embryonic stem cells, and moreover, facilitates the formation of aggregates in static cultures (p 573, col 2, par 1-2). This is vital because hES cells do not survive when transitioned directly from static culture to a suspension culture, and therefore the addition of ROCKi would increase aggregate formation, and subsequently cell survival (p 576, col 1, par 1). Furthermore, the use of Rapamycin, a mTOR inhibitor, revealed at high concentrations the hES cell cultures no longer expanded, but at lower concentrations spontaneous differentiation no longer occurred (p 580, col 1, par 2).
Biffi and Krawetz do not teach the LV comprises a modified Woodchuck Posttranscriptional Regulatory Element having a nucleic acid sequence as set forth in SEO ID NO: 3.
Zanta-Boussif teaches a modified WPRE, specifically mut1, consisting of a single nucleotide mutation in the WHX protein translation start site (Fig. 1). The WPRE sequence overlaps with that of the woodchuck hepatitis virus X protein (WHX), which is a transcriptional activator of about 150 AA implicated in the development of liver tumors. The WPRE inserted in most vectors contains the WHX gene promoter and an open-reading frame coding for the first 61 AA of WHX in its 3’ region (p 606, col 1). Zanta-Boussif found that the mut1 version was as efficient in expressing high levels of the transgene in comparison to the wild-type WPRE sequence, and therefore functioned equivalently despite losing the ability to translate the WHX polypeptide(abstract, p 606, col 2). The mut1 version is displayed below in Fig. 1a:
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The STIC Sequence Search has provided no alignments that are 100% identical, in particular the closest identical sequence is around 99.7% identical as seen below for alignments compared across other Published Applications, specifically the differences are a single nucleotide difference in the same location described by Zanta-Boussif. Provided below is a snapshot of the most similar alignments, in addition to Result #3 (filing date of 03-03-2010) sequence alignment that depicts the same mismatch as Mut1.
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The specification describes SEQ ID NO: 3 as WPRE mut 1 wherein a thymine is mutated to guanine as seen in bold “("t" to "G" mutation site in BOLD)” (p 6, lines 22-24). The region highlighted for SEQ ID NO: 3 is 575 nt in length (sites 1698-2273) wherein the mutation occurs at site 2107 which is the 409th nt: tccaGggct. It appears based on the location and specific mutation made, that Zanta-Boussif teaches this mutation wherein the WHX translation is abrogated, and expression levels of the transgene are maintained.
It would have been prima facie obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have been motivated to include kinase inhibitors to inhibit ROCK and mTOR based on the teachings of Krawetz that describe the combination being necessary for moving stem cells from a static culture to a suspension culture. In particular, the use of a ROCK inhibitor at low concentrations promoted aggregation and the mTOR inhibitor blocked spontaneous differentiation by maintaining pluripotency. Therefore, there would a reasonable expectation that using such inhibitors would have similar outcomes with the HSCs described in the claimed invention wherein multipotency is maintained.
Secondly, it would have been prima facie obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the WPRE of the vector to be have a mutation in the WHX translation start site because Zanta-Boussif teaches the same mutation wherein translation of the WHX is prevented which is implicated in liver tumors, and expression of the transgene is maintained relative to the wild-type version, and altogether functioned equivalently. Therefore, there is a reasonable expectation of success that incorporation of this mut1 sequence by Zanta-Boussif would lead to similar outcomes for the claimed invention in maintaining high expression of the ARSA gene in the self-inactivating (SIN) lentiviral vector.
Claim 2, dependent on claim 15, recites wherein the vector comprises a recombinant ARSA gene under the control of an ARSA gene 5' promoter and an ARSA 3' enhancer.
Biffi teaches lentiviral vectors “(LVs) encoding the human ARSA cDNA under the control of the human phosphoglycerate kinase promoter (PGK)” (p 1233158-1, col 3, par 3). Moreover, Biffi teaches Metachromatic leukodystrophy (MLD) is an inherited lysosomal storage disease caused by mutations in the Arylsulfatase A gene, the reference treated patients diagnosed with MLD wherein gene replacement was accomplished by using lentiviral vectors within hematopoietic stem cells (HSCs).
Biffi does not teach employing the 5’ promoter and 3’ enhancer of ARSA, nor a recombinant ARSA.
It would have been prima facie obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have employed the endogenous ARSA promoter in addition to the enhancer regions found within the genomic sequence based on these sequences being well-known at the time of filing of the claimed invention. In particular, the goal of MLD treatment is to restore ARSA expression with a functional copy, and therefore, it would be obvious to employ all the same endogenous regulatory elements, i.e. promoters, enhancers, absent any evidence of unexpected results. Secondly, in respect to the lentivirus vector encoding a recombinant ARSA, it would have been obvious to modify the coding sequence in view of the system/ organism being used in such as animal studies.
Regarding claim 4, dependent on claim 15, Zanta-Boussif teaches a self-inactivating lentiviral vector that comprises a Rev Responsive Element (RRE) (Fig. 1b).
Regarding claim 5, dependent on claim 15, Biffi teaches the vector contains a central polypurine tract (“cPPT”), in addition to containing a post-translational regulatory element, specifically a modified Woodchuck Post-transcriptional Regulatory Element (WPRE) (“WPREmut6”) (p 5, col 2). Moreover, Zanta-Boussif teaches a self-inactivating vector that comprises a central polypurine tract (Fig. 1).
Regarding claim 9, dependent on claim 15, Biffi teaches the vector encodes the ARSA gene, that is the human ARSA gene (“CD34+ cells were stimulated ex vivo with early acting cytokines in serum-free medium and transduced with purified third-generation LVs encoding the human ARSA cDNA under the control of the human phosphoglycerate kinase promoter (PGK) (fig. S2).”; p 1, col 3, par 3).
Claims 4 and 15 are rejected under 35 U.S.C. 103 as being unpatentable over Biffi et al. (Science 341, 1233158 (2013); of record IDS filed on February 21, 2023; hereinafter ‘Biffi’) in view of Krawetz et al. (Tissue Engineering Part C: Methods 16.4 (2010): 573-582; hereinafter ‘Krawetz’; of record) and Zanta-Boussif et al. (Gene Therapy 16.5 (2009): 605-619; of record IDS filed on February 21, 2023; hereinafter ‘Zanta-Boussif’) as applied to claim 15 above, and further in view of Malik (US-2019/0276844-A1; of record).
The disclosure of Biffi in view of Krawetz and Zanta-Boussif’is applied as in the 103 rejections above, the content of which is incorporated herein, in its entirety.
Regarding claim 4, dependent on claim 15, Biffi does not disclose if the vector used includes an insulator.
Malik teaches a modified self-inactivating (SIN) lentiviral vector for transduction into hematopoietic stem cells (HSCs) that comprises a cHS4 chromatin insulator that permits higher titer expression of the vector and an env fragment containing a rev response element (RRE) that is essential for efficient assembly/packaging of lentivirus particles as opposed to mRNA transport (0020, 0027, 0104, claim 27).
It would have been prima facie obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the lentiviral vector taught by Biffi is to include both an insulator and RRE sequences in order to improve outcomes related to gene expression and viral particle assembly as Malik has described with such sequences. Furthermore, there is an expectation that the combination of these sequences as taught in a lentiviral vector would lead to the predictable outcome of the claimed lentiviral vector having improved gene expression and number of viral particles due to these sequences’ taught characteristics.
Claims 9, 10 and 15 are rejected under 35 U.S.C. 103 as being unpatentable over Biffi et al. (Science 341, 1233158 (2013); of record IDS filed on February 21, 2023; hereinafter ‘Biffi’; of record) in view of Krawetz et al. (Tissue Engineering Part C: Methods 16.4 (2010): 573-582; hereinafter ‘Krawetz’; of record) and Zanta-Boussif et al. (Gene Therapy 16.5 (2009): 605-619; of record IDS filed on February 21, 2023; hereinafter ‘Zanta-Boussif’) as applied to claims 9 and 15 above, and further in view of Oshikawa et al. (Molecular vision 15 (2009): 482.; STIC Sequence Search Result; hereinafter ‘Oshikawa’; of record). The STIC Sequence Search has been supplied in Office Action dated May 15, 2025.
The disclosure of Biffi in view of Krawetz and Zanta-Boussif’ is applied as in the 103 rejections above, the content of which is incorporated herein, in its entirety.
Claim 10, dependent on claim 9, is directed to wherein the ARSA gene has a nucleic acid sequence as set forth in SEQ ID NO: 2. Biffi teaches the human ARSA gene within the vector, “the vector used in this study (pCCLsin.cPPT.hPGK.hARSA.WPREmut6 - PGK.ARSA.LV) is a self-inactivating lentiviral vector produced with a third-generation split packaging system” (p 8, col 2); yet Biffi does not teach the ARSA sequence.
The STIC Sequence Search determined the instant SEQ ID No: 2 is 100% identical to Result #6, ID# AB448736 listed as “Homo sapiens ARSA mRNA for arylsulfatase A, complete cds.” (The full alignment is provided with the Office Action). The sequence was published by Oshikawa et al wherein the reference describes the purpose as “The aim of this study was to characterize the arylsulfatase I (ARSI) gene that has been shown to be preferentially expressed in the human retinal pigment epithelium cell line ARPE-19 and to propose it as a candidate gene responsible for inherited eye diseases such as retinitis pigmentosa (RP).” (Abstract).
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It would have been prima facie obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have employed SEQ ID No: 2 for the ARSA coding sequence of the disclosed vector based on this sequence being well-known at the time of the filing of the instant application as the human ARSA coding sequence.
Conclusion
Claims 2-5, 9-10, and 15 are rejected No claims are allowed.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to MICHAEL A RIGA whose telephone number is (571)270-0984. The examiner can normally be reached Monday-Friday (8AM-6PM).
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Maria G Leavitt can be reached at (571) 272-1085. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/MICHAEL ANGELO RIGA/ Examiner, Art Unit 1634
/MARIA G LEAVITT/ Supervisory Patent Examiner, Art Unit 1634