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 .
Claims status
Applicants reply filed 5/18/2026 is acknowledged.
Claims 2, 22, 23 is/are cancelled. Claims 1, 3-7, 9-12, 14, 17-19, 21, 24 is/are currently pending with claims 9-12, 14, 17-19 is/are withdrawn. Claims 1, 3-7, 21, 24 is/are under examination.
Withdrawn Objections
The objections presented herein represent the full set of objections currently pending in this application. Any objections not specifically reiterated are hereby withdrawn.
Claim Rejections - 35 USC § 112(b) – New, necessitated by claim amendment
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.
Rejection of Claims 4-6, 21 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention is withdrawn in light of claim amendments.
Claims 1, 3-7, 21-24 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Claim 1 amended to recites passaging the cells “at least about” 8 times in line 10. The specification defines about as “within 20%, preferably within 10%, and more preferably within 5% of a given value or range.” [0093]. Thus, in reciting the term “about”, the claim embraces a range of passages, specifically 8 ± 20% of 8 i.e. 6.4-9.6 passages or more reasonably, rounded to 6-10 passages. It is unclear if the claim requires the number of passages to be at least 6 or at least 7 or at least 8 or at least 9 or at least 10. A passage number that is at least 9 could not be 6th, 7th or 8th passage. The phrase “at least about” is unclear. For the purpose of compact prosecution, the claim(s) 1 is/are interpreted as “or more than 10 times”.
Claim 1 amended to recite use of CHIR99021 at a concentration of “at least about” 5uM in line 13. The specification defines about as “within 20%, preferably within 10%, and more preferably within 5% of a given value or range.” [0093]. Thus, in reciting the term “about”, the claim embraces a range of concentrations, specifically 5uM ± 20% of 5uM i.e. 4-6uM. It is unclear if the claim requires the concentration to be at least 4uM or at least 5uM or at least 6uM. A concentration that is at least 6uM could not be 5 or 4uM. The phrase “at least about” is unclear. This is further unclear because claim 3 recites CHIR99021 at a concentration of “about 5uM” in options (a) and (b), thus embracing a concentration range of 4-6uM. For the purpose of compact prosecution, the claim(s) 1 is/are interpreted as “at least 4uM”.
Claim 3-7, 21-24 is/are rejected due their dependence on claim 1 because they do not clarify the 112b issue noted with claim 1.
Claim Interpretation – Updated to address claim amendments
Claim 1 is directed to a method for producing “axial stem cells”. The specification states “As used herein, the term "axial stem cell/s" (or "AxSC/s") may interchangeably be used with the term "neuromuscular-skeletal stem cells" and may refer to cells produced by the methods of the present invention or having characteristics of the cells produced by the methods of the present invention as described herein below” [0079]. Thus, the specification states that the claimed axial stem cells may refer to any cells that are a result of the claimed method or have the characteristics of the claimed method. The claimed method requires exposing either embryonic or induced pluripotent stem cells, derived from human recited in claim 7, to CHIR99021 at about 10uM for about 24 hours and subsequently passage the cells at least about 8 times, using serial passaging recited in claim 24, in the presence of CHIR99021 at least about 5uM along with FGF2 and/or TGFb inhibitor.
As mentioned above, the specification defines about as “within 20%, preferably within 10%, and more preferably within 5% of a given value or range.” [0093] but use of “at least about” raises indefiniteness issues, and interpretation for this phrase is provided above in the U.S.C. 112b rejection.
Thus, the claimed method requires exposing either embryonic or induced pluripotent stem cells, derived from human recited in claim 7, to CHIR99021 at 8-12uM for 19-29 hours and subsequently passage the cells 6-10 times or more, using serial passaging recited in claim 24, in the presence of CHIR99021 at 4uM or more along with FGF2 and/or TGFb inhibitor.
The claim further recites markers expressed by the cells derived from the recited steps, specifically SOX2 along with any one of the listed markers.
Claim 3 recites three alternative combinations of CHIR99021, FGF2 and TGFb inhibitor that each result in 3 distinct cell types with different marker expression, but each still “axial stem cells” since as noted above, the claimed axial stem cells are any cells that are a result of the claimed method.
Claims 4-6 recite additional features of the cells produced by the method of claim 1 using a “wherein clause” and thus represent intended results of the method of claim 1. However, the court noted that a "‘whereby clause in a method claim is not given weight when it simply expresses the intended result of a process step positively recited.’" Id. (quoting Minton v. Nat’l Ass’n of Securities Dealers, Inc., 336 F.3d 1373, 1381, 67 USPQ2d 1614, 1620 (Fed. Cir. 2003)). See MPEP 2111.04.
Claim 4 recites characteristics of “axial stem cells” produced by the method of claim 1. Since these characteristics are of the “axial stem cells” produced by the method of claim 1, these characteristics must necessarily arise from the active steps of claim 1. Thus, prior art anticipating and/or rendering obvious the method of claim 1, results in the “axial stem cells” with the claimed characteristics. Similarly, claim 5, the proteins recited as expressed by the “axial stem cells” are inherent to the axial stem cells produced by the method of claim 1. Similarly for claim 6, the differentiation capabilities of the axial stem cells are inherent to these stem cells and must necessarily arise from the active steps of claim 1. Thus, prior art anticipating and/or rendering obvious the method of claim 1, results in the “axial stem cells” with the claimed characteristics of claims 4-6.
Claim Rejections - 35 USC § 102 - Withdrawn
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
Rejection of Claim(s) 1-7, 22 and 23 under 35 U.S.C. 102(a)(1) as being anticipated by Ashton et al. (US 2016/0068806 A1, Mar. 10, 2016; IDS 7/31/2023) as evidenced by Verrier et al (Development (2018) 145, dev166215; IDS 7/31/2023) is withdrawn in light of claim amendment.
Claim Rejections - 35 USC § 103 – New, necessitated by claim amendment
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.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Rejection of Claim(s) 21 under 35 U.S.C. 103 as being unpatentable over Ashton as applied to claim 1 above, and further in view of Kent (Cell Culture Basics: Stem Cell Media – The “What” and “Why”. Feb 3, 2016.) is withdrawn due to withdrawal of the rejection it relied upon.
Rejection of Claim(s) 24 under 35 U.S.C. 103 as being unpatentable over Ashton as applied to claim 1 above, and further in view of Ashton is withdrawn due to withdrawal of the rejection it relied upon.
Claim(s) 1, 3-7, 21, 24 is/are rejected under 35 U.S.C. 103 as being unpatentable over Ashton et al. (US 2016/0068806 A1, Mar. 10, 2016; IDS 7/31/2023).
Regarding claims 1 and 7, Ashton teaches a method comprising
providing human pluripotent stem cells (PSC), including human embryonic and induced pluripotent stem cells (= step (a); human= as required by claim 7; [003, 0061, 0141]),
activating the Wnt/b-catenin signaling pathway in the said cells using CHIR99021, a GSK3b inhibitor, at a concentration of 1-20uM, specifically reciting 8,10 and 12uM, for at least 24 hours in their method (=step (b); [009, 0095, 0142, 152]; Example 2, 4; Figures 2, 4, 7, 8, 11) and
passaging the cells exposed to CHIR99021 in the presence of CHIR99021 along with FGF2 and/or TGFb inhibitor; wherein CHIR990021 is at a concentration of 1-20uM, specifically reciting 4, 5, 6, 8uM and using 3-6uM in the examples (=step(c) in part; Example 2, 4; [007, 0047, 0048, 0050, 100, 102, 126, 138]; Figures 2, 4, 6, 7, 8, 11; Example 1)
Regarding claim 3 (option a), Ashton teaches passaging cells with CHIR99021 along with FGF2 and further inclusion of SB-431542 as a TGFb inhibitor ([007, 0050, 0088, 100, 126, 0128, 0163]; Figure 2, 4, 6, 7, 8, 11). Ashton teaches the concentration for each of these agents. Ashton teaches CHIR99021 at a concentration of 1-20uM, specifically reciting 4, 5, 6, 8uM and using 3-6uM in the examples (=claimed about 5uM; [0095, 142, 152]). Ashton teaches FGF2 at a concentration of 50-400ng/ml, using 100-200ng/ml in the examples 1 and 4 ([007, 0050, 0088, 0128 0163]; Figure 6). Ashton teaches SB-431542 at a concentration of about 10uM ([0100, 0126]).
Ashton’s method results in SOX-2+ve, T-box+ve and PAX-ve cells ([0011, 129, 0147]; Figure 2, 6; Example 1, 2, 4).
Regarding claim 21, Ashton teaches maintenance of human PSC in suitable PSC media ([0141]).
Regarding claim 24, Ashton teaches serial passaging i.e., wherein cells are reseeded at a lower density (from 1.5x105 to 1.2x105 cells/cm2) in fresh medium, which was serum-free E6 medium ([0141], [0122]).
Regarding number of passages in step 1(c), Ashton teaches that after production of neuromesodermal progenitors, “if extended neuromesodermal propagation was required” then passaging was repeated ([0152], Figure 11). Ashton explicitly teaches passaging the cells produced at least 2 times (Figures 5 and 11).
Ashton does not explicitly teach passaging the produced cells for 6-10 times (=claimed about 8 times). However, Ashton teaches that for extended propagation passaging can be performed and preferred for extended propogation.
Therefore, it would be obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to passage the cells produced by Ashton’s method for more than 2 times as taught by Ashton, such as 6 times or more. An ordinary artisan would be motivated to passage the cells produced by Ashton’s method for 6 times or more to continue to propagate the cells produced. An ordinary artisan would reasonably expect to passage the cells produced by Ashton’s method for at least 6 times because Aston teaches the passaging method.
Taken together, Ashton renders the method steps recited in claim 1, 3, 7, 21 and 24 as prima facie obvious.
Regarding the identity and characteristics of cells produced recited in the claims using wherein clauses, Ashton does not use term “axial stem cells” for the cells produced by their method or identify additional markers such as recited in the claims (MYCN, LIN28B, IRX3, SOX1, ZIC2, or SOX11) or if the cells are “indefinitely renewing” (as recited in claim 1); or if the cells are additionally EOMES positive (as recited in claim 3); or some of the markers and characteristics of cells produced recited in claims 4-6.
However, as noted above, Ashton teaches the active steps recited in the claims. Furthermore, Ashton teaches several markers and characteristics that are same as claimed.
Ashton teaches that the cells derived are endogenous SOX2 positive and method are “reminiscent of the axial stem cell population found in vivo” (as recited in claim 1; Example 2, Figure 2, 7, 11; [0048]). Ashton’s method results in SOX-2+ve, T-box+ve and PAX-ve cells (as recited in claim 3; [0011, 129, 0147]; Figure 2, 6; Example 1, 2, 4).
Ashton teaches that cells produced express SOX2 (Example 2, Figure 2, 7, 11) and are caudal-lateral epiblasts i.e. are region-specific multipotent (Example 1, 2) cells that are obtainable from pluripotent stem cells (Example 1 and 2) (some of the options recited in claim 4). Ashton also teaches that cells SOX-2+ve, T-box+ve (some of the options recited in claim 6; [0011, 129, 0147]; Figure 2, 6; Example 1, 2, 4).
As noted in the claim interpretation above, each of the characteristics of the cells produced by the claimed method must necessarily arise from the claimed active steps. The intended results recited in these claims arise from the active steps positively recited and rendered obvious by Ashton (see MPEP 2111.04 and claim interpretation above).
Therefore, since Ashton obviates the active method steps recited in the claims, Ashton method results in “axial stem cells” with the claimed characteristics.
Therefore, the invention as a whole was prima facie obvious to one of ordinary skill in
the art at the effective time of filing of the invention, especially in the absence of evidence to the
contrary.
Response to Arguments
Applicant argue against claim interpretation recited in previous OA regarding axial stem cells and neuromesodermal progenitors (NMPs) that are each SOX2 positive (page 47, para 3)
Applicant allege that the cells produced by the claimed method are “indefinitely renewing” because they are phenotypically stable over months in culture (page 47, para 4). Applicant allege that this result is “condition-dependent and is not achieved by simply applying Wnt activation at any dose” pointing to [219-220] and Figure 4 that shows concentration below 5uM did not promote cell line formation and above 10uM was toxic (page 47, last para). Applicant allege that the cells produced by the claimed method are not NMPs since the cells other express markers (MYCN, LIN28B, TRX3, SOX1, ZIC2, SOX11) not expressed by NMPs.
In response, specific claim interpretation equating terms used to describe SOX2 positive cells in the art and the specification is now removed. As was noted in the previous claim interpretation, axial stem cells, NMPs and caudal lateral epiblasts are terms used in the art, sometimes interchangeably but a distinction between these terms and critically, cell type is not clear. Therefore, focusing on primarily the active steps which would result in the cells, regardless of the term used for the cells, is more relevant. This is indeed evident from the simple definition for axial stem cells given in the specification [0079] which is that axial stem cells are cells produced by the claimed method.
Regarding the conditions, it must be noted that Ashton teaches concentration of about 5uM and, according to specification, 10uM was toxic only for ESC but not iPSC. Specifically, Ashton also teaches that CHIR99021 concentration to be used is cell line dependent [152].
Regarding markers identified, at first it must be noted that “Mere recognition of latent properties in the prior art does not render nonobvious an otherwise known invention” (see MPEP 2145(II). In example 16, Applicant perform a RNAseq from the cells produced by the claimed method thus identifying additional markers, yet these markers are a result of the active method steps and flow from it. Furthermore, the conclusion that human NMPs do not express these markers is based on comparison of Applicant’s data set with that of Verrier [255] but this conclusion is limited to cells produced by Verrier’s method and not necessarily “NMPs” produced by other methods, such as Ashton’s.
Applicant’s arguments with respect to the U.S.C. 102 rejection of claim(s) 1-7, 22 and 23 have been considered but are moot because the new ground of rejection necessitated by claim amendment.
Arguments pertinent to instant U.S.C. 103 rejection of the claims over Ashton are addressed below.
Applicant allege that Ashton’s method result in “transient NMP-like cells that can be passaged several times but which ultimately differentiate to posterior neuroectoderm or neuroepithelium” while Applicant show that “If hPSCs are not passaged following Wnt/b-catenin
stimulation, SOX2 is quickly down regulated, which prohibits the derivation of axial
progenitors altogether” (page 50, para 1).
In response, Applicant provide no evidence that Ashton’s cells are “transient” or must “ultimately differentiate to posterior neuroectoderm or neuroepithelium”. Ashton teaches specific addition of GDF11 to ultimately differentiate to posterior neuroectoderm or neuroepithelium without which this fate is not achieved (Example 4). Example 1-3 in Ashton do not use GDF11. Furthermore, same as claimed, Ashton also teaches Wnt/b-catenin stimulation and passaging in its presence to maintain neuromesodermal identity [0152].
Of note, the specification does not show that “If hPSCs are not passaged following Wnt/b-catenin stimulation, SOX2 is quickly down regulated”. Rather it shows that if hPSCs are passaged following Wnt/b-catenin stimulation but without continued Wnt/b-catenin stimulation then SOX 2 is down regulated (Figure 1).
Applicant’s arguments with respect to the U.S.C. 103 rejection of claim(s) 24 and 21 have been considered but are moot because claim 21 is now cancelled and the new ground of rejection necessitated by claim amendment for claim 24.
Arguments pertinent to instant U.S.C. 103 rejection of the claims over Ashton are addressed below.
Applicant argue that “Ashton et al. fails to teach or reasonably suggest all of the features of claim 1, and claims 21 and 24 depend from claim 1” (page 50, last para). Applicant allege that Ashton teaches “transient NMP-like cells” that necessarily differentiate into posterior neuroectoderm or neuroepithelium” pointing to Ashton’s Abstract that states hPSC were differentiated into “caudal lateral epiblasts, posterior neuroectoderm or posterior neuroepithelium, or motor neurons having” and Example 4 that teaches differentiation of caudal lateral epiblasts/NMPs into definitive neural identity in the presence of GDF11. Thus, Applicant allege that Ashton is directed to “generating human neural cells” (page 51, para 3).
In response, as above, Applicant provide no evidence that Ashton’s cells are “transient” or must “ultimately differentiate to posterior neuroectoderm or neuroepithelium”. Indeed Ashton teaches generation of each of caudal lateral epiblasts, posterior neuroectoderm or posterior neuroepithelium, or motor neurons however this does not indicate that Ashton does not teach generation of what they term “caudal lateral epiblasts” by using CHIR99021 in combination with at least FGF2.
Regarding example 4, as above, Ashton teaches specific addition of GDF11 to ultimately differentiate to posterior neuroectoderm or neuroepithelium without which this fate is not achieved (Example 4). Example 1-3 in Ashton do not use GDF11. Thus, Ashton is not limited to only human neural cells.
Next, Applicant argue that Ashton does not teach the specifically recited characteristics of indefinite renewal and the markers from example 6 of the instant specification (page 51-52, bridging para).
In response, as above, Ashton teaches the active steps of the claimed method and the recited characteristics are the result of these steps. Although Ashton does not show the characteristics recited in the claims, “Mere recognition of latent properties in the prior art does not render nonobvious an otherwise known invention” (see MPEP 2145(II). In example 16, Applicant perform a RNAseq from the cells produced by the claimed method and compare these markers to RNAseq data of Verrier [255] but not Ashton’s.
Next, Applicant argue that Ashton teaches away from claimed method because it teaches both a TGFb antagonist and also a BMP antagonist in [126] while Applicant show that media comprising CHIR99021 and BMP antagonist do not result in axial stem cells (Figure 4) (page 52, para 1).
In response, it is unclear how in teaching addition of TGFb antagonist or a BMP antagonist could be considered a teaching away. Ashton does not teach that TGFb antagonist inhibits their method and neither does the instant specification. BMP antagonist is not claimed.
Finally, Applicant argue that instant Application shows that “a passaging campaign beginning at 24 hours after CHIR99021 treatment alone and in presence of CHIR99021, produced progeny stably expressing SOX2” and “Surprisingly, permanent activation of Wnt/b-catenin in hESCs and passaging that begins at 24 hours, promote renewal of cells that express the axial marker SOX2, and express one or more of MYCN, LIN28B, IRX3, SOX1, ZIC2, and SOX11.” (page 52, para 2).
In response, indeed the method used by the Applicant starts with CHIR99021 treatment alone and passaging beginning at 24 hours. However, there is no requirement in the claims that the method start with CHIR99021 alone. The claim requires activation of Wnt pathway but does not limit activation of any other pathway. Furthermore, there is no evidence that an initial first step with CHIR alone is required for the results. Indeed the results show that CHIR alone is sufficient but it does not necessitate a conclusion that CHIR must be used alone. Similarly, there is no evidence that first passage must be at 24 hours. Ashton teaches treating cells with CHIR, albeit with FGF, and passaging cells for continued propagation. Arguments pertaining to markers produced are addressed above.
Conclusion
No claim is allowed.
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). 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 MATASHA DHAR whose telephone number is (571)272-1680. The examiner can normally be reached M-F 8am-4pm (EST).
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/MATASHA DHAR/Examiner, Art Unit 1632
/ANOOP K SINGH/Primary Examiner, Art Unit 1632
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