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 .
Application Status
This action is written in response to applicant’s correspondence received 07/30/2026. Claims 10-11, 13-26 are currently pending.
Any rejection or objection not reiterated herein has been overcome by amendment. Applicant’s
amendments and arguments have been thoroughly reviewed but are not persuasive to place the claims in condition for allowance for the reasons that follow.
Priority
This application is a 371 of PCT/EP2022/064233 filed on 05/25/2022. Applicant’s claim for the benefit of a prior-filed application under 35 U.S.C. 119(e) or under 35 U.S.C. 120, 121, 365(c), or 386(c) is acknowledged. Acknowledgment is made of applicant's claim for foreign priority based on an application filed in EP 21175889.1 on 05/26/2021.
Receipt is acknowledged of certified copies of papers required by 37 CFR 1.55.
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.
Claims 10-11, 13-26 are rejected under 35 U.S.C. 103 as being unpatentable over Piao (WO 2021/158789 A1, published on 08/12/2021, filed on 02/04/2021) in view of Saba (eLife 8:e40981; Published 2019), further in view of Yazdan Panah (WO 2017/109161 A1, published on 06/29/2017), claim 13 is evidenced by Fulgenzi (Int. J. Mol. Sci. 2019, 20, 1019).
Piao teaches “methods for reducing, minimizing, or inhibiting the formation of double-stranded ribonucleic acid (dsRNA) during the preparation of ribonucleic acid (RNA) …” (Abstract, lines 1-3), and “in vitro transcription (IVT)” (Page 1, ¶[0005]). Regarding the recitation of the instant claim 10, “for reducing double stranded RNA (dsRNA) formation during in vitro transcription reaction”, it refers to an intended use, therefore is insufficient to distinguish the method of Piao from the claimed method.
Piao further teaches that “The in vitro transcription mixture (starting reaction mixture) generally comprises a DNA template, a transcription buffer, nucleotide triphosphates (NTPs) (natural or modified), magnesium ion, and RNA polymerase(s)…” (Page 14, ¶[0087]), wherein “Magnesium in the transcription mixture is, in certain embodiments, at a final concentration of about 12 to about 60 mM” with at least one embodiment of about 35mM (Page 14, ¶[0089], lines 8-10);
And, the IVT starting reaction mixture was kept for 2-3 hours at selected temperature, i.e. around 37 ° to perform the IVT and synthesize RNA, followed by adding DNase I to digest the DNA template and stop the reaction (Page 16, ¶[0096], last 2 lines; Page 19, ¶[00104], last 2 lines; Page 27, ¶[00130] & [00131]; Table 15; Page 30, ¶[00140]; Page 31, ¶[00144]). Piao uses DNase I to terminate IVT, but Piao does not describe the details of DNase I treatment method.
However, Yazdan Panah teaches that “incubating for 2h at 37°C” is a typical DNase I treatment (Page 40, lines 8 & 12). Neither Piao nor Yazdan Panah teaches that the IVT reaction is terminated by the addition of a metal chelator, wherein the metal chelator being EDTA, or the concentrations of EDTA.
However, Saba (2019) teaches a method of terminating IVT reactions, in that “Reaction samples were removed at various time points and quenched with an equal volume of 2X stop buffer (8 M urea, 50 mM EDTA…” (Page 18, last 2 lines – Page 19, first line; Under the In vitro transcription pause assays section). Hence, Saba teaches terminating IVT using EDTA with a final concentration of 50mM ÷ 2 = 25mM, which is about 24mM.
Regarding claim 10, it would have been obvious to persons having ordinary skill in the art (PHOSITAs) before the effective filing date of the claimed invention to have modified the methods of performing IVT using reaction mixture comprising magnesium at from about 35mM to about 60mM final concentration, taught by Piao, by replacing the DNase I termination step, which takes additional incubation time, in view of Yazdan Panah’s teaching that “incubating for 2h at 37°C” (Page 40, lines 8 & 12), with Saba’s conventional strategy of simply adding the 2X stop buffer that comprises 50mM EDTA at equal volume to the IVT reaction mixture for immediate reaction quenching. It would have merely amounted to simple substitution of known elements in the art according to known methods to yield predictable results. One would have been motivated to do so because The simpler and immediate effect of such an approach offers motivation for PHOSITAs to adopt such an approach under suitable circumstances, e.g. where multiple time points with short intervals for sampling are necessary to assess IVT dynamics in order to determine the optimal reaction time or conditions, such as temperature, chemical compositions, among other variables. Lengthy DNase I digestion, e.g. 2 hours, prevents timely data collection that requires nimble termination of the IVT reactions. One would have reasonable expectations of success because both IVT termination methods are known, interchangeable, and serve the same function to achieve the same outcome.
Regarding claim 11, Piao further teaches that “Pyrophosphatase in the transcription mixture…” (Page 14, ¶[0089], line 17).
Regarding claim 13, EDTA is a metal chelator, as evidenced by Fulgenzi (2019)’s teaching of “chelating agent calcium disodium ethylenediaminetetraacetic acid (EDTA) …” and “a chelating agent able to bind and remove toxic metals” (Page 5/16, section 4. Last two lines).
Regarding claim 14, Piao further teaches, in certain embodiments, “Magnesium in the transcription mixture is, in certain embodiments, at a final concentration of about 12 to about 60 mM” (Page 14, ¶[0089], lines 8-10), therefore, at least some embodiments are at from about 35mM to about 60mM, which are within the claimed ranges of “about 35mM to about 150mM”.
Regarding claim 15, Piao teaches at least some embodiments with about 40mM to about 60mM of magnesium, which are within the range of “about 40mM to about 100mM”.
Regarding claim 16, Piao teaches at least some embodiments with about 45mM to about 60mM of magnesium, which are within the range of “from about 45mM and about 75mM”.
Regarding claim 17, Piao teaches at least one embodiment of about 55mM of magnesium.
Regarding claim 18, Piao further teaches, in certain embodiments, that “Pyrophosphatase in the transcription mixture is, … at a final concentration of about 0.1 to about 10U/mL” (Page 14, ¶[0089], line 17), therefore all those embodiments are within the range of “about 0.01 U/ml to about 40 U/ml”.
Regarding claim 19, Piao teaches embodiments within “about 0.1 U/ml” to “about 20 U/ml”.
Regarding claim 20, Piao teaches at least some embodiments with about 1 U/ml to about 10 U/ml of Pyrophosphatase, which are within the range of “about 1 U/ml to about 10 U/ml”.
Regarding claim 21, Piao teaches at least one embodiment with about 5 U/ml of Pyrophosphatase.
Regarding claim 22, Saba teaches the final concentration of EDTA, the metal chelator, is about 24mM as cited above, and 24mM is within the claimed ranges of “about 10mM to about 50mM”.
Regarding claim 23, Saba teaches the final concentration of EDTA, the metal chelator, is about 24mM as cited above, and 24mM is within the claimed ranges of “about 20mM to about 30mM”.
Regarding claim 24, Saba teaches the final concentration of EDTA, the metal chelator, is about 24mM as discussed above.
Regarding claim 25, Yazdan Panah (2017) further teaches a “Method for in vitro transcription of a nucleic acid template into RNA,…” (Page 41, claim 1) and “Method according to any one of the preceding claims, wherein the magnesium salt is magnesium chloride” (Page 42, claim 9).
Regarding claim 26, Piao further teaches “In certain embodiments, a 5’ cap and/or a 3’ poly A tail can be added independently to the RNA product (for example, transcript product of in vitro transcription (IVT))” (Page 13, ¶[0082] lines 1-3). Since Piao also teaches using modified nucleotide triphosphates (NTPs) in the transcription mixture (Page 14, ¶[0087]), the RNA product of IVT would inherently comprise one or more modified nucleosides.
Response to Arguments
Applicant's arguments filed on 07/30/2026 have been fully considered but they are not
persuasive. Applicant argues on page 8 of the Remarks:
“the inventors unexpectedly found that elevated magnesium reduces dsRNA formation during IVT while maintaining RNA yield and integrity.....”
Applicant’s arguments with respect to combining Piao, Saba, and Yazdan Panah have been considered but not persuasive. The argument above about unexpected results is misplaced because adding Magnesium in the IVT reaction mixture is not a modification as the primary reference Piao anticipates this practice. Piao already teaches the high-Mg condition and its dsRNA-reducing effect as set out in the §102 rejection of the previous office action mailed on 04/30/2026. The only modification is swapping the termination step, DNase I for EDTA. Hence, an argument about obviousness, i.e. an unexpected result, is irrelevant because there is insufficient nexus between the subject of argument regarding what is unexpected, i.e. the addition of Mg2+, and the subject of 103 rejection, which is the obviousness of adding a metal chelator.
Furthermore, unexpected results require evidence. Applicant has the burden to demonstrate actual data that is commensurate in scope with the claims and compared against the closest prior art, which is Piao with DNase I (See MPEP 716.02(b), (d), (e)). Argument alone isn't enough.
Applicant argues on page 9 of the Remarks:
“This addition of metal chelators, thereby sequestering free magnesium ions, in fact achieves a synergistic technical effect:
1. It immediately halts the magnesium-dependent T7 RNA polymerase activity, ensuring precise control over the transcript length.
2. It instantly deprives any contaminating nucleases of the divalent cofactors required for their catalytic activity, thereby preserving the high integrity of the produced mRNA”.
The argument above has been considered but is not persuasive. The argument for a "synergistic technical effect" recites two known functions of adding a metal chelator to IVT reactions, each doing what it always did, by itself. A chelator chelates Mg²⁺, which stops the polymerase, also inhibits contaminating nucleases. Each is a known, inherent result of chelation. Whether there is an synergistic effect or not between two effects of a single modification is irrelevant, because both effects are inherent by adding a metal chelator alone. Recognizing an additional advantage does not make the modification non-obvious, as the rationale different from applicant’s is permissible. See MPEP 2144(IV).
“This specific combination of high-magnesium transcription followed by chelator-mediated termination is neither disclosed nor rendered obvious by the cited references.”
Applicant’s assertion is not evidence. Applicant has provided no evidence of unexpected results regarding the “combination”. See MPEP 716.02; MPEP 2145(I). Replacing Piao's DNase I step with Saba's EDTA quench is a simple substitution of one known termination method for another, with predictable results, as set forth in the office action above and in the previous office action mailed on 04/30/2026. See MPEP 2143(I)(B). One cannot show non-obviousness by attacking the references individually when the rejection is based on their combination. See In re Keller, 642 F.2d 413, 426 (CCPA 1981).
Applicant argues on page 10 of the Remarks:
“The Applicant respectfully submits that the Office has failed to establish that one of ordinary skill in the art would have had a reasonable expectation of success from the alleged combination. The mere fact that references can be combined or modified does not render the resultant combination obvious unless the results would have been predictable to one of ordinary skill in the art. MPEP § 2143.01 (emphasis added).”
The argument above has been considered but is not persuasive. Prior art-derived motivation is supplied with the previous office action mailed on 04/30/2026 and reiterated herein, see §103 above.
Reasonable expectation of success is met. The rejection is based on predictability under MPEP §2143(I)(B) with a rationale of simple substitution. Piao and Saba each teach an IVT method that differs in the termination step; Both methods stop the IVT reaction; The result of swapping the IVT termination methods is predictable to one of ordinary skill in the art since the IVT reaction stops either way.
The rejection under 35 U.S.C. §103 is maintained.
Conclusion
No claims are allowable.
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 Delphinus D. Yu whose telephone number (571) 272-1576. The examiner can normally be reached Mon-Thr 7:30am to 4:30pm Fri 10am to 2pm ET.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Neil P Hammell can be reached on (571) 270-5919. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/DELPHINUS DOU YI YU/Examiner, Art Unit 1636
/NEIL P HAMMELL/Supervisory Patent Examiner, Art Unit 1636
