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 .
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 September 11, 2025 has been entered.
Application Status
Applicant’s remarks and amendments to the claims and drawings filed September 11, 2025 are acknowledged. Claim 21 was amended, claims 13, 15, 25-26, and 29-30 were cancelled, and claims 31-37 were introduced. Claims 4-12, 14, 21, 27-28, and 31-37 are pending.
Restriction/Election
The restriction requirement between Inventions I and II detailed in the action mailed March 4, 2024 has been reconsidered in view of the amendments to the claims and the prior art reviewed during the search. The restriction requirement between Inventions I and II is officially withdrawn. Applicant is advised that if any claim presented in a divisional application is anticipated by, or includes all the limitations of, a claim that is allowable in the present application, such claim may be subject to provisional statutory and/or nonstatutory double patenting rejections over the claims of the instant application. Once a restriction requirement is withdrawn, the provisions of 35 U.S.C. 121 are no longer applicable. See In re Ziegler, 443 F.2d 1211, 1215, 170 USPQ 129, 131-32 (CCPA 1971). See also MPEP § 804.01.
The election of species requirements detailed in the action mailed March 4, 2024 remain in effect. Accordingly, claims 10 and 14 remain withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to nonelected species. Claims 4-9, 11-12, 21, 27-28, and 31-37 are under examination herein.
Withdrawn Rejections
Applicant’s cancellation of claims 25-26 is sufficient to obviate the § 112(d) rejections over the same. The cancellation of claims 29-30 is sufficient to overcome the § 112(a) and § 112(b) rejections over the same. Applicant’s amendments to claim 21 also resolve the § 112(b) rejections over the same. The § 112(d), § 112(b), and § 112(a) rejections raised in the prior action are withdrawn. A thorough search of the prior art uncovered additional art which better covers the independent claims as they are currently presented. Accordingly, the § 103 rejections over Hickey, Ozawa, and Chandler, or the same in further view of Bierwolf are withdrawn, accordingly.
Applicant’s remarks and amendments have been thoroughly reviewed, but are not persuasive to place the claims in condition for allowance for the reasons that follow. Any rejection or objection not reiterated herein has been overcome by amendment.
Priority
The claims under examination find support in provisional Application No. 62/567,631, filed October 3, 2017. The effective filing date of the claims under examination is October 3, 2017.
Claim Objections
Claims 31, 33-36 are objected to because of the following informalities:
Claim 31 recites “wherein the isolated exogenous nucleic acid located within an autologous hepatocyte in spheroids is in a pharmaceutical composition.” Claim 21 requires that the isolated exogenous nucleic acid be located within an autologous hepatocyte and “delivered to the liver as spheroids.” It is clear that the claim intends to require that the isolated exogenous nucleic acid, which is located within an autologous hepatocyte, and in spheroid form, be in a pharmaceutical composition. Accordingly, it would be preferable to amend claim 31 to recite ““wherein the are[[is]] in a pharmaceutical composition.”
It is clear that the term “the nucleic acids” in claim 33 refers to the previously recited “isolated exogenous nucleic acid.” To improve the flow and terminology of the claim relative to claim 21, it would be preferable to amend claim 33 to recite the following: “wherein the isolated exogenous nucleic acid[[s]] coding for the functional fumarylacetoacetate hydrolase protein codes for a human fumarylacetoacetate hydrolase protein.”
On the same basis as described above, it would be preferable to amend claim 34 to recite the following: “wherein the isolated exogenous nucleic acid[[s]] coding for the functional fumarylacetoacetate hydrolase protein has[[ve]] 95% identity to SEQ ID NO: 8.” It would also be preferable to amend claim 35 to recite the following: “wherein the isolated exogenous nucleic acid[[s]] coding for the functional fumarylacetoacetate hydrolase protein comprises SEQ ID NO: 8.”
Claim 36 recites “95% identify” which should be amended to recite “95% identity[[fy]].”
Appropriate correction is required.
Claim Rejections - 35 USC § 112(b)
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.
Claims 11, 21, and 31-37 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. The rejections below are new.
Claim 11 recites the term “older pediatric patient.” Neither the claim nor specification provide a definition of an “older pediatric patient.” The specification provides that “In some embodiments, the human is an older pediatric patient at least 1 year old or greater, and/or 18 years old or less” ([0024]). However, this embodiment does not sufficiently clarify the scope of the term “older pediatric patient” in the claimed method. It is not clear what would qualify as an “older” pediatric patient, compared to any other pediatric patient, and therefore, the scope of the claim is unclear.
Claim 21 recites “the liver,” but no such liver is previously recited in the claim. While the claim previously recites that the method “correct[s] defective genes in hepatocytes,” this phrase does not implicitly require a liver, because the recited hepatocytes could be located ex vivo or in vitro, for example. Accordingly, the term “the liver” lacks sufficient antecedent basis in the claim.
Claim 21 recites “delivering an isolated exogenous nucleic acid located within an autologous hepatocyte to the liver… wherein the isolated exogenous nucleic acid located within an autologous hepatocyte is deliver to the liver as spheroids, wherein the isolated exogenous nucleic acid codes for a functional fumarylacetoacetate hydrolase protein.” The claim then recites “a… []HCR[] is operably linked to a… []hAAT[] promoter that is operably linked to the isolated exogenous nucleic acid… within a lentiviral vector.” These two phrases appear uncoupled, such that the structure of the agent which is delivered to the liver is not clear. At first, the claim sets forth delivering a hepatocyte comprising an isolated exogenous nucleic acid encoding a functional fumarylacetoacetate hydrolase protein as spheroids. Then, the claim recites additional elements which are said to be “operably linked” to the isolated exogenous nucleic acid “within a lentiviral vector,” but no such lentiviral vector appears to be required or implied in the previous phrases. Should it be Applicant’s intent, Examiner recommends amending the claim to recite, for example:
“A method of correcting defective genes in hepatocytes comprising: delivering an autologous hepatocyte in spheroid form to a liver intrahepatically or via portal vein injection, wherein the autologous hepatocyte comprises a lentiviral vector comprising an isolated exogenous nucleic acid coding for a functional fumarylacetoacetate hydrolase protein, wherein the isolated exogenous nucleic acid is operably linked to a hepatic control region enhancer (HCR) operably linked to a human alpha 1-anti trypsin (hAAT) promoter.”
Claims 31-37 are rejected for depending from claim 21 and failing to remedy the indefiniteness.
Response to Remarks - 35 USC § 112(b)
Applicant’s remarks regarding the rejections raised in the prior action have been reviewed. The remarks are moot because the previous rejections have been withdrawn, and none of the arguments specifically address the new grounds of rejection described above.
Notice to Joint Inventors
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 Rejections - 35 USC § 103 – Nyberg in view of Ozawa and Chandler
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.
Claims 4-8, 21, and 27 are rejected under 35 U.S.C. 103 as being unpatentable over Nyberg (Hickey et al., October 2015, “2. Autologous hepatocyte transplantation after ex vivo gene therapy in a large animal model of metabolic liver disease,” Hepatology, Vol. 62, No. 1, pg. 208A) in view of Ozawa (Ozawa et al., US 2005/0147592 A1, published 7 July 2005; of record) and Chandler (Chandler et al., 2015, The Journal of Clinical Investigation, 125(2), p. 870-880; of record). The rejections that follow are new.
Regarding claims 4-6, and 8, Nyberg teaches a method of delivering a lentiviral vector coding for a functional fumarylacetoacetate hydrolase protein to hepatocytes of a subject via portal vein injection (“we tested the hypothesis that ex vivo gene therapy with a lentiviral vector (LV) encoding FAH and autologous hepatocyte transplantation can correct the metabolic disorder in FAH-/- pigs,” “Hepatocytes were transduced with a LV expressing the FAH cDNA under the control of the thyroxine-binding globulin promoter. Pigs received autologous transplants of hepatocytes by portal vein infusion… after 24 hours of LV transduction during 3-dimensional hepatocyte spheroid formation”).
Regarding claims 21 and 27, in view of the indefiniteness described above, claim 21 is interpreted as in the amendment suggested in paragraph 15. Nyberg teaches a method of correcting a defective FAH gene in hepatocytes, which treats subjects with hereditary tyrosinemia (“we tested the hypothesis that ex vivo gene therapy with a lentiviral vector (LV) encoding FAH and autologous hepatocyte transplantation can correct the metabolic disorder in FAH-/- pigs,” “Two pigs… indicat[ed] complete amelioration of the HT1 phenotype… demonstrating complete correction of tyrosine metabolism”). Nyberg teaches the method comprises delivering autologous hepatocytes in spheroid form to hepatocytes of a subject via portal vein injection, wherein the autologous hepatocytes comprise a lentiviral vector comprising an isolated exogenous nucleic acid coding for a functional fumarylacetoacetate hydrolase protein (“Hepatocytes were transduced with a LV expressing the FAH cDNA under the control of the thyroxine-binding globulin promoter. Pigs received autologous transplants of hepatocytes by portal vein infusion… after 24 hours of LV transduction during 3-dimensional hepatocyte spheroid formation”).
Nyberg teaches that the FAH cDNA in the lentiviral vector was “under the control of the thyroxine-binding globulin promoter,” but does not teach that the FAH cDNA is under control of a human alpha1-antityrpsin (hAAT) promoter operably linked to a hepatic control region enhancer.
Ozawa teaches a method of correcting defective FAH gene associated with hereditary tyrosinemia type I, by delivering an isolated exogenous nucleic acid substantially identical to that described by Nyberg (“1. A method of delivering a protein to a mammalian subject having an aminoacidopathy, comprising: a) providing recombinant adeno-associated virus (rAAV)… compris[ing] a heterologous gene encoding a metabolic protein involved in amino acid metabolism; b) administering said rAAV virions… wherein said administering results in transduction of at least one cell…” “5... wherein said aminoacidpathy is hypertyrosinemia. 6… wherein said hypertyrosinemia is tyrosinemia type I.” “13… to the liver of said mammalian subject”, pg. 13; “Tyrosinemia type I is an inherited disorder of tyrosine metabolism associated with deficient activity of fumarylacetoacetate hydrolase”, [0050]; [0041]-[0044]; [0048]-[0057]). Ozawa teaches that expression from the nucleic acid is driven by a liver-specific promoter, which in an especially preferred embodiment is the human alpha1-antitrypsin (hAAT) promoter operably linked to a hepatic control region (“In an especially preferred embodiment, the HAAT promoter is operably linked to an apolipoprotein E hepatic control region”, [0027]). Ozawa teaches that the hepatic control region is “an enhancer element useful for increasing gene expression in the liver” ([0040]).
Chandler teaches that mice delivered viral vectors (“AAV vectors”) carrying a therapeutic gene expressed under control of the TBG promoter develop hepatocellular carcinoma (HCC)(Fig. 5A; “Our results (Figure 5A and Table 1) and those previously reported document HCCs in mice after receiving AAV vectors carrying the TBG… promoter”, pg. 874). Chandler teaches that the hAAT promoter, in contrast, is not associated with HCC, likely because the hAAT promoter did not lead to overexpression of genes local to the integration site (pg. 877, right col.).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have substituted the regulatory element operably linked to the FAH cDNA of Nyberg, for a human AAT promoter and hepatic control region enhancer taught by Ozawa and Chandler. It would have amounted to a simple substitution of known liver-specific regulatory elements, by known means, to yield predictable results. A skilled artisan would have had a reasonable expectation of success in substituting the elements because Ozawa teaches a substantially identical method and isolated exogenous nucleic acid to that of Nyberg, in which the therapeutic metabolic gene, FAH, is most preferably expressed in the liver under control of an human AAT promoter and hepatic control region enhancer. Because Ozawa teaches that the hepatic control region is “an enhancer element useful for increasing gene expression in the liver,” and Chandler teaches that the hAAT promoter, in contrast to the TBG promoter used by Nyberg, is not associated with HCC, a skilled artisan would have been motivated to substitute the regulatory element operably linked to the FAH cDNA of Nyberg, for a human AAT promoter operably linked to a hepatic control region enhancer.
In rendering obvious the substitution of Nyberg’s regulatory elements for a human alpha1-antityrpsin (hAAT) promoter operably linked to a hepatic control region enhancer, instant claims 4-8, 21, and 27 are obvious.
Claim Rejections - 35 USC § 103 – Nyberg, Ozawa, and Chandler, in further view of Hickey
Claims 9, 11-12, 28, and 31-32 are rejected under 35 U.S.C. 103 as being unpatentable over Nyberg (Hickey et al., October 2015, “2. Autologous hepatocyte transplantation after ex vivo gene therapy in a large animal model of metabolic liver disease,” Hepatology, Vol. 62, No. 1, pg. 208A), Ozawa (Ozawa et al., US 2005/0147592 A1, published 7 July 2005; of record) and Chandler (Chandler et al., 2015, The Journal of Clinical Investigation, 125(2), p. 870-880; of record) as applied to claims 4-8, 21, and 27 above, in further view of Hickey (Hickey et al., 27 July 2016, Science Translational Medicine, 8(349), p. 1-10, and Supplementary Materials; of record). The rejections that follow are new.
The teachings of Nyberg, Ozawa, and Chandler are described above and applied as to claims 4-8, 21, and 27 therein.
Hickey teaches a substantially identical method to Nyberg, in which a defective FAH gene in hepatocytes of the liver of a subject are corrected in an effort to treat a patient with hereditary tyrosinemia (Abstract; Fig. 1A-B; Fig. 2A). Hickey’s method also involves delivering autologous hepatocytes comprising a lentiviral vector encoding a functional fumarylacetoacetate hydrolase via portal vein injection (Fig. 2A-B; “A total of four Fah-/- pigs underwent ex vivo gene therapy… Hepatocytes were transduced with… LV-Fah”, pg. 3, right col.; “the pig Fah cDNA was cloned into the TBG vector… to produce the LV-TBG-Fah expression construct”, Methods: LV production, Supplementary Materials; “After LV transduction, between 350 and 864 million live cells were injected through the portal vein or using ultrasound guidance to inject hepatocytes percutaneously,” pg. 3, right col.). Like Nyberg, Hickey teaches that FAH expression was restored in hepatocytes of recipient porcine subjects (“In contrast to the nontransplanted Fah-/- pig (L768), robust FAH expression was detected in Y707 and Y846,” pg. 4, right col.; Fig. 3B-C).
Regarding claims 9 and 11, in view of the indefiniteness related to the term “older pediatric patient,” the term is interpreted as any pediatric patient.
Nyberg teaches that their model “closely resembles the human phenotype,” and their method demonstrates “the feasibility and efficacy of ex vivo gene therapy” for hereditary tyrosinemia type I. Nyberg does not teach a method in a human or pediatric patient.
However, Hickey teaches use of the method for pediatric patients ( “pediatric patients with inborn errors of metabolism in the liver are most likely to benefit from the significant advantages of ex vivo LV gene therapy”, “we believe that ex vivo hepatocyte gene therapy with LV will provide a lasting impact for the treatment of inborn errors of metabolism of the liver in children before their disease has a change to reach an advanced stage”, pg. 8, left col.).
It would have been obvious to one of ordinary skill in the art before the effective filing date to have substituted the porcine subject in the method rendered obvious above, for a human pediatric subject in view of Hickey. It would have amounted to a simple substitution of two subjects amenable to the method based on the prior art, by known means to yield predictable results. The skilled artisan would have had a reasonable expectation of success in substituting the subjects based on the success of Nyberg’s and Hickey’s methods in mammalian subjects, and particularly because Nyberg teaches that their model “closely resembles the human phenotype.” The skilled artisan would have been motivated to substitute the subjects because Hickey teaches that human pediatric patients are the group “most likely to benefit from the significant advantages of ex vivo LV gene therapy,” because it has the potential to treat their disease before it reaches an advanced stage.
Regarding claims 12 and 31, in view of the indefiniteness described above related to claim 31, the claim is interpreted as requiring that the spheroids be delivered as a pharmaceutical composition.
Nyberg teaches the autologous hepatocyte spheroids were delivered via portal vein injection, but does not teach that the delivery was in a pharmaceutical composition.
However, Hickey teaches means to deliver autologous hepatocytes via portal vein injection (“Hepatocyte isolation, transduction, and transplantation,” pg. 8, right col.). Hickey teaches the hepatocytes are suspended in saline prior to transplantation (“hepatocytes were resuspended in saline… and transplanted through portal vein infusion,” pg. 8, right col.).
It would have been obvious to one of ordinary skill in the art before the effective filing date to have delivered the autologous hepatocyte spheroids in the method rendered obvious above in a pharmaceutical composition in view of Hickey. It would have amounted to delivering known hepatocyte spheroids in a known composition suitable for portal vein injection, by known means to yield predictable results. The skilled artisan would have had a reasonable expectation of success in delivering the autologous hepatocyte spheroids in saline as taught by Hickey because Nyberg’s and Hickey’s methods are substantially identical in design and function, and Hickey’s method successfully delivers hepatocytes via portal vein injection. The skilled artisan would have been motivated to deliver the autologous hepatocyte spheroids as taught by Hickey because Nyberg’s methodology is generic, and Hickey provides a detailed methodology to achieve transplantation of autologous hepatocytes in a substantially identical method to Nyberg’s.
Regarding claims 28 and 32, Nyberg’s description of the lentiviral vector is relatively generic, and does not teach the additional elements of the lentiviral vector or their orientation therein required of claims 28 and 32.
However, as stated above, Hickey teaches a substantially identical lentiviral vector to Nyberg’s, which is used for the same purpose. Hickey describes each element of the lentiviral vector and their orientation therein (Fig. 1A). Hickey’s lentiviral vector matches the elements and orientation required of claims 28 and 32.
It would have been obvious to one of ordinary skill in the art before the effective filing date to have prepared the lentiviral vector used in the method rendered obvious above with the additional elements and orientation of the lentiviral vector of Hickey. It would have amounted to preparing an obvious lentiviral vector with elements and orientation of a substantially identical vector for the same purpose, by known means to yield predictable results. The skilled artisan would have had a reasonable expectation of success in preparing the lentiviral vector rendered obvious above as taught by Hickey because Nyberg’s and Hickey’s methods are substantially identical in design and function, and both employ a lentiviral vector encoding a FAH cDNA. The skilled artisan would have been motivated to prepare the lentiviral vector rendered obvious above as taught by Hickey because Nyberg’s lentiviral vector is set forth generically, and Hickey provides a detailed description of the additional functional elements of a lentiviral vector encoding FAH cDNA used in a substantially identical method to Nyberg’s.
Claim Rejections - 35 USC § 103 – Nyberg, Ozawa, and Chandler, in further view of GenBank
Claims 33-37 are rejected under 35 U.S.C. 103 as being unpatentable over Nyberg (Hickey et al., October 2015, “2. Autologous hepatocyte transplantation after ex vivo gene therapy in a large animal model of metabolic liver disease,” Hepatology, Vol. 62, No. 1, pg. 208A), Ozawa (Ozawa et al., US 2005/0147592 A1, published 7 July 2005; of record) and Chandler (Chandler et al., 2015, The Journal of Clinical Investigation, 125(2), p. 870-880; of record) as applied to claims 4-8, 21, and 27 above, in further view of GenBank (Homo sapiens cDNA, FLJ94596, Homo sapiens fumarylacetoacetate hydrolase (fumarylacetoacetase)(FAH), mRNA, GenBank: AK313951.1, available 24 May 2008). The rejections that follow are new.
The teachings of Nyberg, Ozawa, and Chandler are described above and applied as to claims 4-8, 21, and 27 therein. Nyberg teaches that their method “closely resembles the human phenotype,” and demonstrates “the feasibility and efficacy of ex vivo gene therapy” for hereditary tyrosinemia type I.
None of Nyberg, Ozawa, or Chandler teach a human functional fumarylacetoacetate hydrolase protein (claim 33), that the nucleotide sequence encoding the protein comprises SEQ ID NO: 8 (claims 34-35), or that the encoded protein comprises SEQ ID NO: 9 (claims 36-37).
GenBank teaches a nucleotide sequence encoding a human functional fumarylacetoacetate hydrolase protein, which as shown in the attached alignments comprises 100% identity to SEQ ID NO: 8. In addition, GenBank teaches the protein sequence encoded by the nucleotide sequence (“/translation= “MSF…”). As shown in the attached alignment, the protein sequence disclosed by GenBank is 100% identical to SEQ ID NO: 9.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have substituted the generic FAH cDNA of Nyberg for the human FAH cDNA of GenBank. It would have amounted to a simple substitution of a generic FAH cDNA for a known, human FAH cDNA, by known means to yield predictable results. The skilled artisan would have had a reasonable expectation of success in substituting the two FAH cDNAs because they encode the same protein, and therefore, the skilled artisan would expect that the sequence disclosed by GenBank, when encoded in the lentiviral vector, would have the same effect as the FAH cDNA of Nyberg. Because Nyberg teaches the method is feasible and efficacious for treatment of hereditary tyrosinemia type I, a disease in humans, the skilled artisan would have been motivated to substitute the two FAH cDNAs in an effort to further develop the therapy for use in human subjects.
Response to Remarks - 35 USC § 103
Applicant’s remarks regarding the prior art rejections raised in the prior action have been reviewed. As stated above, the prior art rejections relied upon in the prior action were withdrawn. Accordingly, the remarks are addressed hereinafter as they apply to the new rejections above.
Regarding the use of a human alpha1-antitrypsin (hAAT) promoter and hepatic control region enhancer, Applicant asserts that because Ozawa’s teaching is prophetic, the skilled artisan would not have been motivated to replace the TBG promoter with the recited promoter-enhancer combination. Applicant also submits that because Ozawa’s vector is not a lentiviral vector, the skilled artisan would not would have had a reasonable expectation of success, or had motivation to modify the prior art lentiviral vector with Ozawa’s human alpha1-antitrypsin (hAAT) promoter and hepatic control region enhancer. Finally, Applicant asserts that Chandler’s teachings regarding the TBG promoter do not apply to the use of lentiviral vectors, because Chandler teaches insertional mutagenesis and subsequent genotoxicity of AAV vectors, not lentiviral vectors.
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 this case, the ordinarily skilled artisan at the time of filing would have had substantial understanding of viral vectors used for therapeutic purposes, and the elements necessary and/or advantageous for use in such vectors, e.g., liver-specific promoters and enhancers. This is clearly established by at least Ozawa, Chandler, and Hickey, each of which teach viral vectors comprising various regulatory elements, including the specific promoter and enhancer combination specifically claimed. The skilled artisan would have understood that a TBG promoter and the recited promoter-enhancer combination have the same purpose, regardless of viral vector type (i.e., regulating expression of a desired transgene). The skilled artisan would have had sufficient skill to prepare a lentiviral vector with the recited promoter-enhancer combination. Beyond argument, Applicant does not present any evidence that teaches or suggests that the skilled artisan would not have predicted success in substituting a TBG promoter for the recited promoter-enhancer combination in a lentiviral vector.
Examiner has also established motivation to substitute the TBG promoter for the recited promoter-enhancer combination in a lentiviral vector. Ozawa teaches a substantially identical method to Nyberg’s, in which the recited promoter-enhancer combination is an “especially preferred embodiment.” Furthermore, Chandler teaches that the hAAT promoter, in contrast to the TBG promoter used by Nyberg, is not associated with hepatocellular carcinoma (HCC). Examiner has acknowledged in the previous action and above that the viral vectors used by Chandler are AAV vectors. However, the skilled artisan, again, having substantial knowledge of viral vectors used for therapeutic purposes, would have understood that Chandler’s teachings were relevant to Nyberg’s lentiviral vectors, because lentiviral vectors also integrate into the genome. Beyond argument, Applicant has not provided any evidence that the skilled artisan would have interpreted the teachings of Chandler as applying exclusively to AAV vectors.
Applicant also asserts that the claimed method exhibits “surprising differences between delivery of an autologous hepatocytes and spheroids,” and provides results (1)-(6) for consideration. Examiner has considered Applicant’s evidence of alleged surprising results, the teachings of the prior art, and guidance related to consideration of surprising results in the MPEP. MPEP 716.02(b) states that the “burden [is] on Applicant to establish that results are unexpected and significant;” evidence relied upon should establish “that the differences in results are in fact unexpected and unobvious and of both statistical and practical significance.”
Result (1) alleges that a higher percentage of the initial dose of hepatocytes remains in the liver following single cell administration vs. spheroid administration. A review of Fig. 19A referenced in [0181] and the accompanying description in [0047], indeed, leads to the conclusion that a greater percentage of the initial dose is present in the liver of mice delivered single cells compared to mice delivered spheroids. This result is not significant based on the specification (“approached significance,” [00181]). Furthermore, it is not evident what practical significance this observation has with regard to the instantly claimed methods of delivering a nucleic acid encoding a functional FAH protein, correcting defective genes, or treating tyrosinemia, particularly given the success of Nyberg (using spheroids), and Hickey (using single cells) in substantially identical methods to those claimed.
Results (2)-(4) allege that spheroid administration results in different biodistribution within the liver, and more heterogenous distribution compared to single cells. The data corresponding to the results in paragraphs [0181]-[0182], and [0187] appears to be qualitatively derived from very few samples, calling in to question the statistical significance of the results. The practical significance of this observation is also not evident with respect to the instantly claimed methods. Furthermore, the specification states that “[d]istribution of cells was comparable between single cell and spheroid animals” ([0029]). The specification also states that “there was no significant difference in the overall biodistribution in terms of total cells in the liver between single cell hepatocytes and hepatocytes spheroids” ([0187]). Regarding heterogeneity, the specification states that “[h]eterogeneity in distribution of intraportally transplanted single cell hepatocytes within the liver has been previously described” ([0187]). Given that heterogeneity is observed for intraportally transplanted single cell hepatocytes, it is not evident that the observations of heterogeneity for intraportally transplanted spheroid hepatocytes is unexpected.
Result (5) is not surprising in view of the success of Nyberg’s substantially identical method.
Regarding result (6), which alleges that hepatocytes cultured to generate spheroids demonstrate “significantly higher efficiency of vector transduction and a comparable overall volume of cells within the liver after transplantation, despite showing a more heterogenous biodistribution than single cell hepatocytes.” First, the results related to heterogeneity are addressed above. Regarding the comparable overall volume of cells in the liver after transplantation, Bierwolf shows successful engraftment and preserved function following hepatocyte spheroid transplantation (Table 2; Fig. 2-4; pg. 750). In addition, Mao (Hickey et al., 2015, Liver Transplantation, 21: 442-453) teaches that FAH-positive hepatocyte spheroids “integrate[] normally” into FAH-/- mice livers (pg. 448). Thus, it does not appear unexpected based on the success of the prior art that hepatocyte spheroids would exhibit a “comparable overall volume of cells within the liver after transplantation.” Finally, Applicant appears to establish the alleged “significantly higher efficiency of vector transduction” based on the percent of GFP positive cells (see Fig. 18A-C). The level of GFP positivity is not a direct measurement of the efficiency of vector transduction, but is a direct measurement of transgene expression. Higher and prolonged transgene expression has been previously observed in hepatocyte spheroids compared to single cell cultures. For example, Uchida (Uchida et al., 2014, Biomaterials, 35 (2014), pg. 2499-2506) teaches that hepatocyte spheroids “showed approximately 10 times higher levels of luciferase expression that those in hepatocytes in suspension form over a period of one month” (pg. 2501, right col.; Fig. 2). In view of the prior art, it is not apparent that the higher levels of GFP positivity observed for hepatocyte spheroids vs. single cells is surprising.
Taken together, Applicant’s remarks and evidence of alleged surprising results are not sufficient to overcome the rejections above.
Conclusion
No claims are allowed.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to JENNA L PERSONS whose telephone number is (703)756-1334. The examiner can normally be reached M-F: 9-5pm.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, JENNIFER A DUNSTON can be reached at (571) 272-2916. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/JENNA L PERSONS/Examiner, Art Unit 1637
/Soren Harward/Primary Examiner, TC 1600