DETAILED ACTION
This Office action details a non-final action on the merits for the above referenced application No. Claims 3, and 5-26 are pending in this application.
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 .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 5 Mar. 2026 has been entered.
Status of Claims
Claims 1-2 and 4 are cancelled. Claims 8-26 are withdrawn.
Response to Amendment
The amendments filed on 5 Mar. 2026 have been entered.
Response to Arguments
The rejection of claims 3-7 under 35 USC 103 as being unpatentable over Chaumeil et al. (Nature Com.; published 2013), in view of McInnes et al. (Accounts Chem. Res.; published 1975) and Springsteen et al. (US 2020/0231527 A1; published 23 Jul. 2020), in further view of Cabella et al. (US 2015/0273086 A1; published 1 Oct. 2015) is withdrawn.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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.
Claim(s) 3, and 5-6 is/are rejected under 35 U.S.C. 103 as being unpatentable over Chaumeil et al. (Nature Com.; published 2013), in view of McInnes et al. (Accounts Chem. Res.; published 1975) for the reasons cited in the Office action filed on 9 Oct. 2025.
Claim(s) 3, and 5-7 is/are rejected under 35 U.S.C. 103 as being unpatentable over Chaumeil et al. (Nature Com.; published 2013), in view of McInnes et al. (Accounts Chem. Res.; published 1975), in further view of Cabella et al. (US 2015/0273086 A1; published 1 Oct. 2015) for the reasons cited in the Office action filed on 9 Oct. 2025.
Applicants Arguments
Applicants assert that Chaumeil does not teach an enriched composition of 1-13C-5-12C-alpha ketoglutarate such that the 12C at instant Ca and Cd is of about 99.9% isotope abundance and 13C is about 99% to about 99.9% abundance. Chaumeil does not disclose or suggest incorporating into the same molecule a 13C atom to amplify MRI signal and a 12C atom to decrease MRI signal much less realize that such a combination could be used to improve imaging results. Nowhere does McInnes disclose or suggest incorporating into the same molecule a 13C atom to amplify MRI signal and a 12C atom to decrease MRI signal much less realize that such a combination could be used to improve imaging results.
Applicant's arguments filed 6 Feb. 2026 have been fully considered but they are not persuasive. Chaumeil teaches [1-13C]α-KG as a promising agent for the in vivo interrogation of IDH1 mutational status and activity and Chaumeil shows that [1-13C]α-KG can detect the production of hyperpolarized [1-13C]2-HG in lysates and orthotopic tumors of cells engineered to express mutant IDH1 but not in lysates or tumors of their isogenic counterparts engineered to express wild-type IDH1. Chaumeil teaches that the [1-13C]α-KG composition therein is contaminated with a [5-13C]α-KG originating from the 1.1% natural abundance of 13C at the 5 position. At pg. 3, Chaumeil teaches that given the ~1 ppm linewidth of the 184 ppm resonance in vivo and in light of our findings in cell extracts showing that [5-13C]α-KG and [1-13C]2-HG are only 0.1 ppm apart these two resonances could not be spectrally resolved. Chaumeil recognizes [5-13C]α-KG as a contaminant and Chaumeil provides reason and motivation to one of ordinary skill in the art to remove the [5-13C]α-KG contaminant from the [1-13C]α-KG composition to better detect the [1-13C]2-HG the indicative of mutant IDH1 tumors. McInnes teaches 12C enrichment as a means to eliminate 13C signals originating from the natural abundance. According to McInnes, metabolites obtained by this 13C-depletion method should in principle give 13C spectra containing resonances for only the 13C-labeled positions.
See Ex parte Stern, 13 USPQ2d 1379 (Bd. Pat. App. & Inter. 1987) where it was held that claims to interleukin-2 purified to homogeneity were held unpatentable over references which recognized the desirability of purifying interleukin-2 to homogeneity in view of a method which taught a method of purifying proteins to homogeneity wherein the prior art method was similar to the method disclosed by the applicants.
It would have been obvious to a person of ordinary skill in the art before the effective filing date to modify the composition of Chaumeil so that the [1-13C]α-KG composition is essentially pure 1-13C-5-12C-alpha ketoglutarate as taught by Chaumeil and McInnes because that essentially pure composition would have been expected to advantageously enable a more sensitive method of detecting mutant IDH tumors free of the [5-13C]α-KG that confounds [1-13C]2-HG detection.
Conclusion
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/Michael G. Hartley/Supervisory Patent Examiner, Art Unit 1618
/SEAN R. DONOHUE/
Examiner, Art Unit 1618
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