DETAILED ACTION
Applicant’s amendment and Arguments/Remarks received on 27 March 2026 have been entered. Claims 1-39, 41-43, 69, 75, 77, 79, and 83 were previously pending in the application. Claims 2-9, 11-15, 17-22, 24, 26, and 29 have been newly cancelled by Applicant. Claims 1, 10, 16, 23, 25, 27-28, 30-39, 41-43, 69, 75, 77, 79, and 83 are currently pending in the application. Claims 1, 39, 41, 43, 69, 75, 77, 79, and 83 are independent claims.
The election of Group I, drawn to a non-human animal, a non-human animal cell, a nucleic acid, a targeting vector for generating a humanized endogenous TTR locus, a method of assessing the activity of a human-TTR-targeting reagent in vivo, and a method of optimizing the activity of a human-TTR-targeting reagent in vivo, remains in effect in the instant application. The following election of species remains in effect in the instant application:
TTR 3’ UTRs: a. human
Signal peptides: a. human
TTR locus sequences: a. SEQ ID NO: 24
Claims 75, 77, 79, and 83 remain withdrawn from consideration as being directed to a nonelected invention, there being no allowable generic or linking claim.
Claim 10 remains withdrawn from consideration as being directed to a nonelected species, there being no allowable generic or linking claim.
Claims 1, 16, 23, 25, 27-28, 30-39, 41-43, and 69 are currently pending and under examination in the instant application. An action on the merits follows.
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA . The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Priority
The present application is a 35 U.S.C. 371 national stage filing of International Application No. PCT/US2021/023674, filed 23 March 2021, which claims priority to U.S. Provisional Application No. 62/993,289, filed 23 March 2020.
Thus, the earliest possible priority for the instant application is 23 March 2020.
Claim Objections
The objection to amended and cancelled claims 1-9, 11, 13-16, 23-25, 29, 36-39, 41-43, and 69 for reciting abbreviations without first writing out the term for which they are abbreviated is withdrawn.
Claim Rejections - 35 USC § 112(b)
The rejection of amended and cancelled claims 8, 13, 16, 29, 33-34, 36-37, 38, and 69 under 35 U.S.C. 112(b) as failing to particularly point out and distinctly claim the subject matter which the inventor(s) regards as the invention for multiple issues of indefiniteness is withdrawn in view of Applicant’s amendments to the claims.
**The following new rejection is necessitated by Applicant’s amendments to the claims.
Amended claims 1, 16, 23, 25, 27-28, 30-39, 41-43, and 69 are newly 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. Amended claims 16, 23, 25, 27-28, 30-38, 43, and 69 are included in this rejection due to their dependence on or encompassing of independent claim 1.
Amended independent claims 1, 39, 41, and 42 each recite the limitation "the corresponding human TTR sequence" in line 8 (claims 1 and 39), line 7 (claim 41), and lines 7 and 16-17 (claim 42), respectively. There is insufficient antecedent basis for this limitation in the claim. None of claims 1, 39, 41, nor 42 have any prior recitations of a corresponding human TTR locus. Humans may be considered to have a single TTR locus, and as such use of the article “the” would be appropriate in referring to “the human TTR locus” or “the corresponding human TTR locus”. However, the TTR gene sequence itself is variable within the human population. As such, there is not one inherent “the human TTR sequence” nor “the corresponding human TTR sequence”.
Additionally, "the corresponding human TTR sequence" is recited within the context of “wherein a region of the endogenous TTR locus from the TTR start codon to the TTR stop codon has been deleted and replaced with a human TTR sequence comprising the corresponding human TTR sequence and a human TTR 3’ untranslated region”.
In the prior action, the phrase “corresponding human TTR sequence” was afforded its broadest reasonable interpretation to include any sequence of the human TTR gene locus which otherwise meets the explicit limitations of the claims (e.g., comprising both a TTR exonic sequence and a TTR intronic sequence as recited in the previous versions of independent claims 1, 39, 41, and 42). However, independent claims 1, 39, 41, and 42 as amended do not recite any explicit structural limitations with respect to a “corresponding human TTR sequence”. As such, it is unclear what is meant to be encompassed by a “corresponding human TTR sequence”. For example, it is unclear whether “corresponding” is meant to indicate that the human TTR sequence is merely from the homologous human gene and therefore comprises any sequence of the human TTR gene or whether “corresponding” is meant to indicate some kind of parallel or equivalent structure of the human TTR sequence with respect to the mouse genome sequence being deleted. If the later, then it is unclear whether “corresponding” is meant to encompass some level of equivalency with respect to the coding sequence, such as replacing the region of the endogenous TTR locus from the TTR start codon to the TTR stop codon with the full coding sequence of the human TTR sequence, or whether “corresponding” is meant to encompass a stricter level of equivalency with respect to the genome sequence, such that the region of the endogenous TTR locus from the TTR start codon to the TTR stop codon requires replacement with the full region of the human TTR locus from the human start codon through to the human stop codon.
Therefore, the metes and bounds of the claim cannot be determined.
Independent claims 41 and 42 each further recite, “the endogenous TTR locus” in lines 5-6 and 5, respectively, which is indefinite because claim 41 is a nucleic acid and claim 42 is a targeting vector. Nucleic acids on their own cannot have endogenous locus outside of the context of a cell. Additionally, a targeting vector itself cannot have an endogenous locus since it is not an organism or cell.
Additionally, recitation of “the endogenous TTR locus” also lacks antecedent basis since it is not an inherent property of a nucleic acid or an inherent property of a targeting vector.
Therefore, the metes and bounds of the claim cannot be determined.
Claim Rejections - 35 USC § 103
The rejection of amended and cancelled claims 1-9, 11-16, 23-39, 41-43, and 69 under 35 U.S.C. 103 as being unpatentable over Zhao et al. [2008, Genes to Cells, 13, 1257-1268, IDS]; in view of Devoy et al. [2012, Nature Reviews Genetics, 13, 14-20]; Yu et al. [US20130316366A1, published 28 November 2013]; NCBI [2002, Homo sapiens BAC clone RP11-549B18 from 18, complete sequence, GenBank: AC017100.4, retrieved on 04 January 2026 from: <https://www.ncbi.nlm.nih.gov/nuccore/AC017100.4>, updated 25 January 2002]; Nagata et al. [1995, Journal of Biochemistry, 117(1), 169-175, IDS]; Saelices et al. [2018, Proceedings of the National Academy of Sciences, 115(29), E6741-6750, IDS]; Wei et al. [2004, Amyloid: The Journal of Protein Folding Disorders, 11, 113-120, IDS]; Butler et al. [2016, Amyloid: The Journal of Protein Folding Disorders, 23(2), 109-118]; Konermann et al. [2015, Nature, 517, 583-588]; and Chu et al. [2016, BMC Biotechnology, 16(4), 1-15]; is withdrawn over cancelled claims 2-9, 11-15, 24, 26, and 29 and maintained over amended claims 1, 16, 23, 25, 27-28, 30-39, 41-43, and 69. Applicant's amendments to the claims and arguments have been fully considered but have not been found persuasive in overcoming the rejection for reasons of record as discussed in detail below.
Applicant amended the independent claims 1, 39, 41, and 42 to recite limitations incorporated from previously rejected cancelled dependent claims 2-9, 11-15, 24, 26, and 29. Amendments to dependent claims address issues of indefiniteness and/or update the claim to be consistent with amended independent claim 1. No new limitations have been added which were not already addressed in the obviousness rejection under 35 U.S.C. 103 in the prior action.
Accordingly, Applicant’s amendments do not overcome a finding of obviousness under 35 U.S.C. 103 over Zhao, Devoy, Yu, NCBI, Nagat, Saelices, Wei, Butler, Konermann, and Chu.
Applicant argues that:
One of ordinary skill in the art would not have had a reasonable expectation of success in generating the claimed homozygous humanized TTRV30M rodents with the claimed serum levels of human TTR; and
The claimed rodents are an unexpectedly superior humanized TTR model compared to the mice with inserted human TTR cDNAs in Zhao with respect to the serum levels of human TTR.
However, this is not agreed.
In response to Applicant’s arguments against the references individually, it is noted that the test for obviousness is not whether the features of a secondary reference may be bodily incorporated into the structure of the primary reference; nor is it that the claimed invention must be expressly suggested in any one or all of the references. Rather, the test is what the combined teachings of the references would have suggested to those of ordinary skill in the art. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981). One cannot show nonobviousness by attacking references individually where the rejections are based on combinations of references. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981); In re Merck & Co., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986). Further, the Examiner recognizes that obviousness may be established by combining or modifying the teachings of the prior art to produce the claimed invention where there is some teaching, suggestion, or motivation to do so found either in the references themselves or in the knowledge generally available to one of ordinary skill in the art. See In re Fine, 837 F.2d 1071, 5 USPQ2d 1596 (Fed. Cir. 1988), In re Jones, 958 F.2d 347, 21 USPQ2d 1941 (Fed. Cir. 1992), and KSR International Co. v. Teleflex, Inc., 550 U.S. 398, 82 USPQ2d 1385 (2007). In addition, it must be recognized that any judgment on obviousness is in a sense necessarily a reconstruction based upon hindsight reasoning. But so long as it takes into account only knowledge which was within the level of ordinary skill at the time the claimed invention was made, and does not include knowledge gleaned only from the applicant's disclosure, such a reconstruction is proper. See In re McLaughlin, 443 F.2d 1392, 170 USPQ 209 (CCPA 1971).
Specifically, regarding Applicant’s arguments 1) and 2), Applicant references the instant working examples and instant Figure 5 for teaching that the claimed humanized TTR V30M locus is capable of expressing V30M TTR at serum levels of ~30 µg/mL. Instant Figure 5 shows hTTR levels in blood plasma samples of the humanized hTTRWT/WT and hTTRV30M/V30M mice, wherein hTTRWT/WT mice average about 55 µg/mL hTTR and hTTRV30M/V30M mice average about 30 µg/mL [0069].
As acknowledged in the prior rejection, Zhao provides a western blot showing serum hTTR levels, but does not disclose quantification of the serum levels of the hTTR expressed from the humanized TTR locus.
Applicant references Li et al. (2018) Lab Invest. 98(4):512-524, IDS, to teach the hTTR levels resulting in a mouse taught by Zhao. Li teaches a mouse having a humanized TTR locus as taught by Zhao, which has been bred with a mouse having a humanized RBP4 locus to generate a double-humanized mouse expression hTTR and hRBP4, which form a complex in the blood [abstract]. Li Figure 2 presents serum hTTR levels for such double-humanized mice, along with serum hTTR levels for transgenic mice as taught by Nagata et al. [1995, Journal of Biochemistry, 117(1), 169-175, IDS, cited in the prior action] (i.e., Ttr+/+:Tg[6.0hTTRMet30]), wherein the transgenic mice express about 150 µg/mL hTTR in serum and the double-humanized mice express about 6-7 µg/mL hTTR in serum.
The teachings of Li for the +/+:Tg (i.e., Ttr+/+:Tg[6.0hTTRMet30]) mouse agree with the teachings of Nagata, which show that the 6.0-hMet30 transgenic mouse lines are capable of producing serum hTTR levels of up to about 171 µg/mL and that the 0.6-hMet30 transgenic mouse lines produce serum hTTR levels up to about 34 µg/mL [Nagata Figure 2]. Therefore, Nagata and Li each teach that hTTR can be expressed, secreted into the blood, and circulate in the blood of a mouse at a concentration at least as high as 171 µg/mL.
Note, however, that the data Li presents for the serum levels of hTTR from the humanized mouse “hV/hM:hR/hR”, while comprising the same hTTR cDNA construct inserted into the mTTR locus, is not the same mouse line presented by Zhao. The mouse of Li has been cross-bred with a humanized hRBP4 mouse to generate the “hV/hM:hR/hR” (i.e., TtrhTTRVal30/Met30:Rbp4hRBP4/hRBP4) double-humanized mouse [abstract]. As taught by Li, the mouse comprising a humanized hTTR gene locus in the absence of a humanized hRPB4 gene locus will express human TTR, which will then associated with mouse RBP4 [abstract]. Li teaches that the association of human TTR with mouse RBP4 results in different kinetic and thermodynamic stability profiles of the TTR tetramers compared to hTTR-hRPB4 in humans [abstract]. Therefore, given the teachings of Li that hTTR-mRBP4 vs hTTR-hRBP4 have different kinetic and thermodynamic stability profiles, it follows that serum hTTR levels for a hV/hM:hR/hR doubly humanized mouse are not representative of nor equivalent to serum hTTR levels in a homozygous hMet30 singly humanized mouse.
Additionally, Zhao also teaches wherein TTR is synthesized in the liver and secreted therefrom into the blood plasma [column 1 ¶ 1]. Zhao further teaches that the hTTR is expressed from the endogenous mouse TTR promoter in a similar pattern to the mouse endogenous Ttr gene in terms of tissue-specific expression as well as in terms of expression levels, such that the hTTR expression levels in the humanized mouse liver are comparable to mTTR levels in a wild-type mouse liver [column 16 ¶ 4, Figure 1, 3A, 3C, 4A-B]. Although Zhao does not provide absolute quantitation, Zhao teaches that the hTTR serum levels in the humanized mouse are similar to the mTTR serum levels in a wild-type mouse, wherein the normalized mTTR levels for the wild-type mouse are about 2.25 and the normalized mTTR levels for the homozygous hTTR are about 0.6 [Figure 4C]. Note further that the heterozygous +/Val30 mouse produced mTTR and hTTR levels which were essentially identical at about 1.25 [Figure 4C]. Although the serum levels for the homozygous hTTRVal30 taught in Figure 4C are lower than the levels for homozygous wild-type mTTR, the hTTRVal30 levels are only reduced by about 75% compared to the homozygous wild-type mTTR and about 50% compared to the heterozygous mTTR. Note additionally that Figure 3C teaches that the serum levels of hTTR in the Val30/Val30, Val30/Met30, and Met30/Met30 humanized mice are all nearly identical to each other, such that the relationship between the Val30 hTTR serum levels and the wild-type mTTR serum levels would be expected to be equivalent to a relationship between the Met30 hTTR serum levels and the wild-type mTTR serum levels. Therefore, the ordinarily skilled artisan at the time of filing the instant application would expect that the Met30 hTTR in the humanized TTR mouse will express at a level comparable to the normal endogenous mTTR expression level and be present in the serum of the mouse at a level that is about 50-75% of the normal homozygous wild-type mTTR level.
Note that although the hTTR transgene of Nagata is expressed from the exogenous human TTR promoter, Nagata teaches that the liver expression levels of the 0.6-hMet30-62 hTTR transgene are nearly identical to the liver expression levels of the wild-type mTTR in a wild-type control mouse (see, for example, the 0.25 µg slot for the liver in figure 4a) [Figure 4].
Therefore, given the teachings of Zhao that the hTTR liver expression levels within the humanized mouse are comparable to the mTTR liver expression levels in a wild-type mouse, and the teachings of Nagata that the liver expression levels of hTTR in the 0.6-hMet30-62 transgenic mouse are comparable to the liver expression levels of mTTR in a wild-type mouse; an ordinarily skilled artisan at the time of filing would expect that the hTTR serum levels in the humanized TTR mouse of Zhao would likewise be comparable to the hTTR serum levels in the 0.6-hMet30-62 transgenic mouse of Nagata (i.e., 20 µg/ml) [Figure 2a]. As such, an ordinarily skilled artisan at the time of filing would expect the humanized TTR mouse of Zhao to exhibit serum hTTR levels of about at least 20 µg/ml with a reasonable expectation of success. Accordingly, it would not have been unexpected to an ordinarily skilled artisan at the time of filing the instant application to achieve serum levels of transthyretin protein expressed from the humanized endogenous TTR locus in the rodent of at least 20 µg/ml.
Therefore, Applicant’s arguments do not overcome a finding of obviousness under 35 U.S.C. 103 over Zhao, Devoy, Yu, NCBI, Nagat, Saelices, Wei, Butler, Konermann, and Chu, and the rejection is maintained.
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.
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DR. KATIE L. PENNINGTON
Examiner
Art Unit 1634
/KATIE L PENNINGTON/Examiner, Art Unit 1634
Dr. A.M.S. Wehbé
/ANNE MARIE S WEHBE/Primary Examiner, Art Unit 1634
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