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 .
DETAILED ACTION
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 06/03/2026 has been entered.
Response to Amendment
The amendment filed 08/25/2025, amending claims 1, 6, 7, 9, 15, 19, and cancelling claims 2, 4, 5, 17 and newly adding claim 53 is acknowledged. Claims 1, 6-11, 13, 15, 19, 21-25, 27, 29-37, 39, 41-43, 45, and 53 are pending. Claims 21-25, 27, 29-38, 41-43, and 45 remain withdrawn. Claims 1, 6-11, 13, 15, 19, and 53 are pending and under examination.
Applicant’s amendments to the claims have overcome each and every claim objection, 112(b) rejection, and 112(d) rejection previously set forth in the Final Office Action mailed 12/03/2025.
The rejection of claims 1, 13, 15, 19 under 35 U.S.C. 102(a)(2) as being anticipated by or, in the alternative, under 35 U.S.C. 103 as obvious over Benenato as evidenced by Colorado State is withdrawn. Applicant has amended the base claim to remove “human JAG1”, which Benenato was referenced for disclosing/teaching in the claimed method. As such, the rejection of claims 6-11 under 35 U.S.C. 103 as being unpatentable over Benenato, Colorado State, and further in view of Chen and Cameron is similarly withdrawn.
Priority
Applicant' s claim for the benefit of a prior-filed provisional application 62/663,675 filed on 04/27/2018 and PCT/US19/29501 filed 04/26/2019 under 35 U.S.C. 119(e) or under 35 U.S.C. 120, 121, or 365(c) is acknowledged.
Claim Objections
Claim 7 is objected to because of the following informalities:
For consistency, the examiner recommends adding “coding region” after “TGFBR1” in line 2.
Appropriate correction is required.
Applicant is advised that should claim 1 be found allowable, claim 9 will be objected to under 37 CFR 1.75 as being a substantial duplicate thereof. When two claims in an application are duplicates or else are so close in content that they both cover the same thing, despite a slight difference in wording, it is proper after allowing one claim to object to the other as being a substantial duplicate of the allowed claim. See MPEP § 608.01(m).
Claim 9 recites “wherein the human TGFBR1 coding region is borne by a vector”. The recitation “borne by a vector” does not add to or change the structure of the method (e.g., as written, the use of the term “vector” does not alter the structure from that of the polynucleotide).
Claim Rejections - 35 USC § 112(a)- Written Description
The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
The following is a quotation of the first paragraph of pre-AIA 35 U.S.C. 112:
The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention.
Claims 1, 6-11, 13, 15, 19, and 53 are rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the written description requirement. The claim(s) contains subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for applications subject to pre-AIA 35 U.S.C. 112, the inventor(s), at the time the application was filed, had possession of the claimed invention.
Claim 1 recites “a method of inducing transdifferentiation of a hepatocyte into a mature cholangiocyte comprising introducing at least one expressible coding region of human Transforming Growth Factor Beta Type I Receptor (TGFBR1) into the hepatocyte of a human patient with a cholestatic disease or cholestatic injury under conditions where the expression of the at least one expressible coding region is greater than the wild- type level of expression in the hepatocyte, thereby inducing transdifferentiation of the hepatocyte into a mature cholangiocyte”.
In analyzing whether the written description requirement is met for genus claims, it is first determined whether a representative number of species have been described by their complete structure. To provide adequate written description and evidence of possession of a claimed genus, the specification must provide sufficient distinguishing identifying characteristics of the genus. The factors to be considered include disclosure of complete or partial structure, physical and/or chemical properties, functional characteristics, structure/function correlation, methods of making the claimed product, or any combination thereof. The disclosure of a single species is rarely, if ever, sufficient to describe a broad genus, particularly when the specification fails to describe the features of that genus, even in passing. (see In re Shokal 113USPQ283(CCPA1957); Purdue Pharma L.P. vs Faulding Inc. 56 USPQ2nd 1481 (CAFC 2000).
The court explained that “reading a claim in light of the specification, to thereby interpret limitations explicitly recited in the claim, is a quite different thing from ‘reading limitations of the specification into a claim,’ to thereby narrow the scope of the claim by implicitly adding disclosed limitations which have no express basis in the claim.” The court found that applicant was advocating the latter, i.e., the impermissible importation of subject matter from the specification into the claim.). See also In re Morris, 127 F.3d 1048, 1054-55, 44 USPQ2d 1023, 1027-28 (Fed. Cir. 1997).
The broadest reasonably interpretation of the claims encompasses in vivo, in vitro, and ex vivo contexts (claim 19 limits to in vivo), which includes but is not limited to in vitro cell culture, tissue culture, organoid models, and direct application to cells in a human.
The genus “cholestatic disease or cholestatic injury” is generically recited. The specification fails to provide further guidance on what is and is not considered “a cholestatic disease or injury”, noting in [0009]:
In some embodiments, the injury, such as a tissue or organ injury, results from a disease, such as human Alagille syndrome (ALGS), biliary atresia, cystic fibrosis, alpha-1 antitrypsin deficiency, progressive familial intrahepatic cholestasis, arthrogryposis-renal dysfunction-cholestasis syndrome, trihydroxycoprostanic acidemia, trisomy 17,trisomy 18,trisomy 21, primary biliary cholangitis, primary sclerosing cholangitis, autoimmune hepatitis, acute rejection of liver transplant, chronic rejection of liver transplant, liver transplant ischemia, bone marrow transplant-induced chronic graft-versus-host disease, Hodgkin lymphoma, Langerhans cell histiocytosis, macrophage activation syndrome, cytomegalovirus (CMV) infection, reovirus type 3 infection, rubella infection, hepatitis C infection, hepatitis B infection, Epstein-Barr Virus (EBV) infection; microbe infection, sarcoidosis, or idiopathic adulthood ductopenia.
In some embodiments, the disease is human Alagille syndrome (ALGS), biliary atresia, cystic fibrosis, alpha-1 antitrypsin deficiency, progressive familial intrahepatic cholestasis, arthrogryposis-renal dysfunction-cholestasis syndrome, trihydroxycoprostanic acidemia, trisomy 17,trisomy 18, or trisomy 21.
In some embodiments, the disease is human Alagille syndrome (ALGS) wherein the expressible coding region introduced into hepatocytes of the patient encodes JAG1, JAG2, DLL1, DLL3, DLL4, NOTCHi, NOTCH2, NOTCH3, NOTCH4 or any one or more of the respective NOTCH intracellular domains.
In some embodiments, the disease is primary biliary cholangitis, primary sclerosing cholangitis, autoimmune hepatitis, acute rejection of liver transplant, chronic rejection of liver transplant, liver transplant ischemia, bone marrow transplant-induced chronic graft-versus-host disease, Hodgkin lymphoma, Langerhans cell histiocytosis, macrophage activation syndrome, infections (CMV infection, reovirus type 3 infection, rubella infection, hepatitis C infection, hepatitis B infection, Epstein-Barr Virus infection; microbe infection, sarcoidosis, or idiopathic adulthood ductopenia.
In some embodiments, the disease is human Alagille syndrome (ALGS), biliary atresia, cystic fibrosis, alpha-1 antitrypsin deficiency, progressive familial intrahepatic cholestasis, arthrogryposis-renal dysfunction-cholestasis syndrome, trihydroxycoprostanic acidemia, trisomy 17,trisomy 18, or trisomy 21.
In some embodiments, the disease is primary biliary cholangitis, primary sclerosing cholangitis, autoimmune hepatitis, acute rejection of liver transplant, chronic rejection of liver transplant, liver transplant ischemia, bone marrow transplant-induced chronic graft-versus-host disease, Hodgkin lymphoma, Langerhans cell histiocytosis, macrophage activation syndrome, infections (CMV infection, reovirus type 3 infection, rubella infection, hepatitis C infection, hepatitis B infection, Epstein-Barr Virus infection; microbe infection, sarcoidosis, or idiopathic adulthood ductopenia.
In some embodiments, the disease is human Alagille syndrome (ALGS), primary biliary cholangitis, or primary sclerosing cholangitis.
The promoter(s) of the claims is/are recited at a high level of generality (e.g., no promoter recited in claim 1; claim 7 further limits to a constitutive promoter; claim 8 further limits to the EF1alpha promoter).
The breadth of the claimed genus of cholestatic diseases or injuries reasonably encompasses a wide variety of diseases/injuries that impact, are impacted by, or related to the flow of bile through the biliary system. These diseases may have different mechanisms of action, however, and are not limited to diseases/injuries that most directly impact the bile duct (e.g., cystic fibrosis is a genetic condition largely affecting the lungs, while autoimmune hepatitis is a chronic liver diseases where the immune system mistakenly attacks liver cells; both diseases are listed in claim 13). The examples provided in the specification only relate to Alagille syndrome (ALGS), which does not provide much guidance to an artisan on what all the undisclosed species of cholestatic diseases or injuries are. Claims 13 and 15 to further limit what the cholestatic disease or injury of the patient may be.
Further, there is no recitation in the claims or disclosure in the specification for an artisan on the route of administration(s), dose(s), formulation(s), etc. (e.g., how is the TGFBR1 coding region introduced to the cell?) that is necessary/sufficient to “induce transdifferentiation of hepatocyte into a mature cholangiocyte” in a hepatocyte of a human patient with a cholestatic disease or injury. Example 8 of the specification investigates whether activating TGFbeta signaling in hepatocytes enhances HpBD formation by intravenously injecting mice with an AAV8 vector expressing constitutively active TGFBR1 from the Ef1alpha promoter. The examiner notes that in the Applicant’s remarks filed 06/03/2026,the Applicant states that [0050] of Example 1 of the specification, which teaches 1x10^11 viral genomes (vg) of AAV-Ef1alpha-caTgfbr1 being delivered by tail vein injection, pertains to Example 8 as well. Reflecting improved bile drainage, cholestasis, and liver fibrosis resolved faster in treated mice. The specification concludes from this data that TGFbeta signaling in hepatocytes enhances HpBD formation, and drives transdifferentiation and morphogenesis in HpBD formation.
While Example 8 discusses whether the findings are relevant for human ALGS, pSMAD3 IF was used to determine if TGFbeta signaling is active in pBDs of regenerative nodules from liver samples of 2 patients.
No other working examples involved TGFBR1.
Therefore, an artisan is unable to determine the necessary conditions and amount of at least one expressible coding region of TGFBR1 introduced into a hepatocyte of a human patient with a cholestatic disease or injury to necessarily/predictably induce transdifferentiation. Further, there is not enough necessary/sufficient guidance in the disclosure on what expression level is necessary to predictably induce transdifferentiation of the hepatocyte into a mature cholangiocyte.
Chen, Simeng, et al. "Transforming growth factor β1 (TGF-β1) activates hepcidin mRNA expression in hepatocytes." Journal of Biological Chemistry 291.25 (2016): 13160-13174 is considered relevant prior art for teaching transfecting hepatocytes from human patients undergoing partial hepatectomy for metastatic liver tumors of colorectal cancer and hepatocytes from the livers of C56BL/6JRj mice with human recombinant TGF-B1. Additionally, Chen et al. injected AdTGFB1 into the tail vein of male C56BL/6JRj mice. Further, primary murine hepatocytes underwent adenoviral transduction to introduce ALK5 (also known as TGFBR1) (pg. 13161; “Experimental Procedures”). Chen teaches “To test whether TGF-B1 induces hepcidin in wild-type mice, adenovirus encoding constitutively active TGF-B1^223/225 or DL70–3 control virus was injected into C56BL/6JRj mice through the tail vein. Constitutively active TGF-B1^223/225 is preferentially expressed in hepatocytes after systemic intravenous
adenovirus vector injections (38, 39). 4 days after injection, hepatic porcine TGF-B1^223/225 mRNA was highly induced in the AdTGF-B1^223/225 injected group but was undetectable in the untreated and control virus-injected group (AdCON) (data not shown). Consistently, hepatic TGF-B1 signaling was activated, as evidenced by increased phosphorylation of Smad3 (Fig. 2A) and increased mRNA levels of the hepatic target gene Pai1 (Fig. 2C).We further observed a small increase of hepcidin mRNA levels in the liver, indicating that the hepcidin response to TGF-B1 is preserved in vivo (Fig. 2C).
In summary, Chen et al. showed that TGF-beta1 mRNA levels are increased in mouse models of iron overload and that TGF-beta1 contributes to hepatocyte hepcidin activation via an ALK5 and Smad1/5-dependent signaling pathway (pg. 13172, col 1, “The Role of TGF-B1-mediated Hepcidin Regulation”). Chen is silent on whether the introduction of TGF-beta1 induced transdifferentiation of the hepatocytes into mature cholangiocytes.
Zu (US Patent 9,512,406, by inventors) is considered relevant prior art for teaching methods for treatment of a liver disease or injury in a patient comprising administering immature hepatocytes produced by a process in which cells are incubated in a first composition to generate induced multipotent progenitor cells from which endoderm progenitor cells differentiated and subsequently immature and mature hepatocytes are differentiated (claim 1). Zu teaches that endodermal progenitor cells can be differentiated into hepatocytes in a composition (e.g., a medium) containing a TGF-beta inhibitor, basic fibroblast growth factor (bFGF), bone morphogenetic protein 4 (BMP4), dexamethasone, hepatocyte growth factor (HGF), oncostatin M (OSM), a Notch inhibitor (e.g., compound E (C-E)), or any combination on thereof (paragraph [0165] of the published application). However, Zu et al., does not identify administration into hepatocytes of a patient of at least one expressible coding region gene that induces transdifferentiation of mature hepatocytes into cholangiocytes.
Sparks (2010; Hepatology, Pgs. 35-43) is considered relevant art for further teaching that four Notch receptors (Notch1 [N1], N2, N3, and N4) transduce signals from two families of ligands (Jagged1 [Jag1], Jag2, Delta-like-1 [Dll1], Dll3, and Dll4) expressed on the surface of neighboring cells, where mutations in both JAGGED1 (JAG1) and NOTCH2, a Notch pathway ligand and receptor, respectively, cause Alagille syndrome (AGS) (page 35; col. 1). However, Sparks et al., evidences that only N1 is critical for maintenance of major bile duct branches into adulthood while N3 and N4 are redundant and N2 is not sufficient to maintain tubular structures outside the local portal environment into adulthood (page 1399; col.1). Sparks teaches an expressible coding region of NOTCH1 inducibly expressed under control of the ubiquitously expressed ROSA26 locus (page 1392 col.1) and states “to date, no mouse model has inactivated Notch signaling and disrupted all IHBD formation. This limits our ability to definitively affirm that Notch signaling is required for cholangiocyte specification” (page 1399; col.1).
Sparks is silent on the potential role of TGFBR1 in transdifferentiatrion of hepatocytes into mature cholangiocytes and ALGS.
Meindl (Meindl‐Beinker, Nadja M., and Steven Dooley. "Transforming growth factor‐β and hepatocyte transdifferentiation in liver fibrogenesis." Journal of gastroenterology and hepatology 23 (2008): S122-S127.) is considered relevant prior art for teaching that stimulation of hepatocytes with TGF-beta regulates the expression of genes involved in epithelial mesenchymal transition (EMT) and fibrosis. Additionally, in a mouse model, hepatocyte-specific overexpression of Smad7 was able to blunt a fibrogenic response after CCl4 intoxication (Abstract). However, Meindl does not teach the treatment of TGF-beta nor the overexpression of Smad7 in hepatocytes inducing transdifferentiation into mature cholangiocytes that form at least one bile duct.
Hasegawa (Drugs (2021) 81:1181–1192) is considered relevant post-filing art and teaches that cholestatic liver disease is represented by primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC), with different pathophysiological pathways causing bile stasis in both diseases (abstract). Thus, Hasegawa highlights the unpredictability of forming a bile duct using different expressible coding regions, as cholestatic liver diseases/injuries differ in etiologies and therapeutic end points.
Limaye et al. (Limaye, Pallavi B., et al. "Expression of hepatocytic-and biliary-specific transcription factors in regenerating bile ducts during hepatocyte-to-biliary epithelial cell transdifferentiation." Comparative hepatology 9.1 (2010): 9.) (previously cited in EP examination action) is considered relevant prior art for studying the acquisition of biliary specific transcription factors by hepatocytes leading to reprogramming of BEC-specific cellular profile as a potential mechanism of transdifferentiation in two different models of compromised biliary regeneration in rats (Abstract).
Gradient of TGFb expression regulated by Onecut transcription factor HNF6 in ductal plate hepatoblasts during embryonic liver development is crucial for biliary differentiation. In the present study, TGFb1and HNF6 expression pattern was studied in order to determine if similar mechanism is recapitulated during hepatocyte to BEC transdifferentiation in the adult liver. (pg. 2, col 1, para 3).
Compared to controls (Figure 6A), TGFb1 induction was observed in the region surrounding the biliary ductules after DAPM treatment in both the models under study (Figure 6B and 6C). However, after DAPM toxicity, no significant change in HNF6expression was observed (Additional File 2, Figure S2, B and C).
Limaye et al. notes that in a different study, TGFb1 induction was observed in the in vitro hepatocyte organoid cultures undergoing biliary transdifferentiation. Additionally, recently TGFb1-treated fetal hepatocytes were found to behave as liver progenitors and also gain expression of CK19 [24]. Limaye et al. concludes that the data from their study suggest that TGFb1 signaling can lead to transdifferentiation without any changes in the HNF6 expression in the adult liver upon need.
Limaye et al. is silent on the specific role TGFBR1 may play in hepatocyte to BEC transdifferentiation.
In summary, the prior art does not provide further guidance on the relationship between the structure (i.e., active method step) claimed in claim 1 of the instant case and its claimed resulting function(s). Additionally, although the art does teach exposing hepatocytes to TGFB or indirectly inducing TGFB1 in hepatocytes, the art does not teach introducing a coding region of TGBR1 by in hepatocytes leading to the transdifferentiation of hepatocytes into mature cholangiocytes, let alone in vivo/in human patients.
Additionally, the claims are considered to lack adequate written description for failing to recite the structure that is necessary and sufficient to cause the recited functional language (e.g., inducing transdifferentiation).
The specification fails to disclose what structural changes to the method steps of claim 1
(e.g., promoter) is necessary and sufficient to induce transdifferentiation of human patient hepatocytes into cholangiocytes, and thus the ordinary artisan would not know what modification(s) must be made in order to fulfill the instant recitation.
The specification offers minimal guidance on the promoter(s) of the claimed invention. The claim is far broader in scope than the working example(s) of the specification. For example, Example 8 of the specification discloses the use of a ELFalpha1 promoter in the AAV8 vector comprising the heterologous polynucleotide TGFBR1. Example 9 discloses the use of a CMV promoter in the AAV8 vector comprising JAG1. Additionally, [0008] recites:
“In some embodiments, the TGFBR1 coding region is a constitutive allele, or the TGFBR1 is under the expression control of a constitutive expression control element, e.g., a constitutive promoter, such as the Elongation Factor la (EFla) promoter”.
[0033] recites:
“Expression control elements contemplated for inclusion in this aspect of the disclosure are heterologous promoters, such as strong promoters, constitutive promoters, inducible promoters, repressible promoters, and any combination thereof known in the art. Other contemplated expression control elements include enhancers, strong ribosome binding sites (e.g., sites conforming more closely to the Kozak consensus sequence for expression in eukaryotic cells), an altered intron sequence or length, stronger intron donor and acceptor splice sites, a polyadenylation sequence, or a transcriptional termination element. Preferred expression control elements for delivery to hepatocytes according to the disclosure are heterologous promoters and enhancers.”
The claims fail to recite, and the specification fails to disclose, a nexus between the required promoter that the coding region of claim 1 is under control of and the corresponding functional property(ies) of inducing transdifferentiation of the hepatocyte into a mature cholangiocyte.
Therefore, the claims fail to recite, and the specification fails to disclose the nexus of the structure of claim 1 and the function of transdifferentiating hepatocytes of human patients with a cholestatic disease or injury into mature cholangiocytes.
Claim Rejections - 35 USC § 112(a)- Scope of Enablement
The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
The following is a quotation of the first paragraph of pre-AIA 35 U.S.C. 112:
The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention.
Claims 1, 6-11, 13, 15, 19, and 53 are rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, because the specification, while being enabling for:
an in vitro method of transdifferentiating hepatocytes into mature cholangiocytes, comprising introducing an AAV8 vector comprising at least one expressible coding region of human TGFBR1 under the control of an EF1alpha promoter into a hepatocyte, and
an in vivo method of transdifferentiating hepatocytes into mature cholangiocytes, comprising introducing an AAV8 vector comprising at least one expressible coding region of human TGFBR1 under the control of an EF1alpha into a hepatocyte via intravenous, bile duct, or direct liver injection,
does not reasonably provide enablement for a method of inducing transdifferentiation of a hepatocyte into a mature cholangiocyte comprising introducing at least one expressible coding region of human TGFBR1 under control of a generically recited genus of promoters via a vast genera of methods of transduction and transfection recited at a high level of generality. The specification does not enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to use the invention commensurate in scope with these claims.
While determining whether a specification is enabling, one considers whether the claimed invention provides sufficient guidance to make and use the claimed invention. If not, whether an artisan would have required undue experimentation to make and use the claimed invention and whether working examples have been provided. When determining whether a specification meets the enablement requirements, some of the factors that need to be analyzed are: the breadth of the claims, the nature of the invention, the state of the prior art, the level of one of ordinary skill, the level of predictability in the art, the amount of direction provided by the inventor, the existence of working examples, and whether the quantity of any necessary experimentation to make or use the invention based on the content of the disclosure is “undue” (In re Wands, 858 F.2d 731, 737, 8 USPQ2ds 1400, 1404 (Fed. Cir. 1988)). Furthermore, USPTO does not have laboratory facilities to test if an invention will function as claimed when working examples are not disclosed in the specification. Therefore, enablement issues are raised and discussed based on the state of knowledge pertinent to an art at the time of the invention. And thus, skepticism raised in the enablement rejections are those raised in the art by artisans of expertise.
The factors to be considered in determining whether undue experimentation is required are summarized in In re Wands, 858 F.2d 731, 737, 8 U.S.P.Q.2d 1400, 1404 (Fed. Cir. 1988) (a) the breadth of the claims; (b) the nature of the invention; (c) the state of the prior art; (d) the level of one of ordinary skill; (e) the level of predictability in the art; (f) the amount of direction provided by the inventor; (g) the existence of working examples; and (h) the quantity of experimentation needed to make or use the invention based on the content of the disclosure. While all of these factors are considered, a sufficient number are discussed below so as to create a prima facie case.
The Breadth of the Claims and The Nature of the Invention
The Examiner incorporates herein the analysis discussed above in the 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, written description rejection.
The claims are directed to a method of inducing transdifferentiation of a hepatocyte into a mature cholangiocyte, the method comprising introducing a at least one expressible coding region of human Transforming Growth Factor Beta Type I Receptor (TGFBR1) into a hepatocyte of a human patient with a cholestatic disease or cholestatic injury under conditions where the expression level of the at least one expressible coding region of TGFBR1 is greater than the wild- type level of expression in the hepatocyte, thereby inducing transdifferentiation of the hepatocyte into a mature cholangiocyte.
None of the claims recite an action-taking step of administering the heterologous polynucleotide to a patient, or administering the hepatocytes that comprise the heterologous polynucleotide to the patient. Although claim 19 recites introducing the coding region into the hepatocytes in vivo, no dose, route of administration, volume, formulation, etc. is recited.
The claims are broad for reasonably encompassing a multitude of gene therapy methods, including but not limited to CRISPR, and a vast genus of viral vectors such as adenoviruses, lentiviruses, AAVs, etc.
The claims are broad for reasonably encompassing any disease or injury related to the flow of bile in the biliary system (e.g., any cholestatic disease or cholestatic injury).
The State of the Prior Art, The Level of One of Ordinary Skill and The Level of Predictability in the Art
The Examiner incorporates herein the analysis discussed above in the 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, written description rejection.
Considering the mode of administration, the specification simply requires administration of the AAV to the subject by any means. The art has demonstrated through numerous publications, delivery of nucleic acid vectors in vivo is highly unpredictable for successful human therapy.
At issue in general are organ barriers, failure to persist, side-effects in other organs, T-cell responses, virus neutralizing antibodies, humoral immunity, normal tropism of the vector to other organs and more. The challenge is to maintain the efficiency of delivery and expression while minimizing any pathogenicity of the virus from which the vector was derived. The inability to develop an adequate means of overcoming obstacles such as humoral; responses and refractory cells limits the successful means by which the nucleic acid can be administered. The physiological art is recognized as unpredictable. (MPEP 2164.03.) In cases involving predictable factors, such as mechanical or electrical elements, a single embodiment provides broad enablement in the sense that, once imagined, other embodiments can be made without difficulty and their performance characteristics predicted by resort to known scientific laws. In cases involving unpredictable factors, such as most chemical reactions and physiological activity, the scope of enablement obviously varies inversely with the degree of unpredictability of the factors involved. In this case, the nucleic acid is broadly stated as being administered to a patient. The lack of guidance exacerbates the highly unpredictable field of gene therapy and the method of delivery of polynucleotides is highly unpredictable to date. Gene delivery has been a persistent problem for gene therapy protocols and the route of delivery itself presents an obstacle to be overcome for the application of the vector therapeutically.
To date, no single mode of gene transfer has provided a viable option for successful gene therapy protocols Daya et al (Gene Therapy Using Adeno-Associated Virus Vectors, Clin. Microbiol. Rev. 21(4): 583-593, 2008; pg 590-591, joining ¶). When considering AAV therapy, there are many obstacles to its use systemically- host cell immune response which leads to toxicity (Daya et al, pg 587, col 2), blood brain as well as cellular barriers against the virus, adequate expression, degradation of the vector or the product. Even the use of targeting methods and tissue specific promoters have done little to overcome the numerous obstacles related to gene delivery. Even use of tissue specific promoters and capsids targeting has not successfully overcome these obstacles. Taken together with the large breadth of target tissues and diseases claimed, in light of the difficulties to overcome even one of these barriers, one could not perform the full breadth of the claims.
The Existence of Working Examples and The Amount of Direction Provided by the Inventor
The Examiner incorporates herein the analysis discussed above in the 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, written description rejection.
The specification fails to provide any evidence that the method as written can predictably and reliably induce transdifferentiation of hepatocytes from a patient with cholestatic disease or injury into mature cholangiocytes with any promoter, via any method of transfection or transducing, and via any route of administration.
As discussed in the 112(a) written description rejection above, the specification identifies in Example 8, the TGFβ signaling as the driver of hepatocyte transdifferentiation and Hepatic bile duct (HpBD) formation in mice following tail vein injection of AAV8-EF1alpha-caTGFBR1 [0081].
In relation to introducing a heterologous polynucleotide under conditions where the expression level of the coding region is greater than the wild-type level of expression, the specification contemplates increasing expression of a normal, or wild-type, allele of a TGFβ or Notch pathway gene such as TGFBR1 or JAG1 using CRISPR technology (paragraph [0012]). However, there are not examples of introducing expressible coding regions using CRISPR technology, let alone other conditions (other than what is discussed above) that when introduced into hepatocytes of a patient, convert hepatocytes into mature cholangiocytes.
In relation to expression control elements, the specification also discloses enhancers, strong ribosome binding sites (e.g., sites conforming more closely to the Kozak consensus sequence for expression in eukaryotic cells), an altered intron sequence or length, stronger intron donor and acceptor splice sites, a polyadenylation sequence, or a transcriptional termination element (paragraph [0033]). However, except for systemic administration of the recombinant adeno-associated Virus serotype 8 (AAV8), wherein expression of constitutively active Jag1
is under the control of a constitutive expression control element, e.g., CMV-Jag1 (paragraph [0082]), there are not teachings of other expression control elements that would predictably result in introducing in vivo into hepatocytes of a patient an expressing said heterologous polynucleotides to convert hepatocytes into mature cholangiocytes.
The specification fails to make up for the deficiencies of the global scientific community.
The Quantity of Any Necessary Experimentation to Make or Use the Invention
Thus, the quantity of necessary experimentation to make or use the invention as claimed, based upon what is known in the art and what has been disclosed in the specification, will create an undue burden for a person of ordinary skill in the art to demonstrate that at least one expressible coding region of human TGFBR1 or human JAG1 to human hepatocytes of the broadly encompassing recitation of a patient with a cholestatic disease or injury so as to necessarily and predictably achieve the transdifferentiation of hepatocytes into mature cholangiocytes.
It is generally recognized in the art that biological compounds often react unpredictably under different circumstances (Nationwide Chem. Corp. v. Wright, 458 F. supp. 828, 839, 192 USPQ95, 105(M.D. Fla. 1976); Affd 584 F.2d 714, 200 USPQ257 (5th Cir. 1978); In re Fischer, 427 F.2d 833, 839, 166 USPQ 10, 24(CCPA 1970)). The relative skill of the artisan and the unpredictability of the pharmaceutical art are very high. Where the physiological activity of a chemical or biological compound is considered to be an unpredictable art (Note that in cases involving physiological activity such as the instant case, "the scope of enablement obviously varies inversely with the degree of unpredictability of the factors involved" (See In re Fischer, 427 F.2d 833, 839, 166 USPQ 10, 24(CCPA 1970))), the skilled artisan would have not known how to extrapolate the results provided in the instant specification to necessarily and predictably for transdifferentiate hepatocytes in patients with a plurality of etiologically and pathologically distinct cholestatic disease and injuries.
The gene therapy art is unpredictable. The unpredictability is manifested in the poor and unpredictable targeting of the gene therapy vectors to target cells (e.g., possible vectors), routes of administration, the transient and unpredictable expression of the transgenes in target cells (e.g., possible promoters and/or regulatory sequences), the specific genes to be used for a treatment (e.g., the generically recited genus of expressible coding regions), and the unsuitability of many animal models of human diseases (as discussed below), all of which are critical for the success of a gene therapy method.
Reliance on animal models is not predictive of clinical outcome. This has been complicated by the inability to extrapolate delivery methods in animals with those in humans or higher animals.
Mingozzi and High (Immune responses to AAV vectors: overcoming barriers to successful gene therapy, Blood 122(1): 23-36, 2013) demonstrate that the human findings are not recapitulated from the animal studies (page 26, col 2, “it seemed logical that one could model the human immune response in these animals, but multiple attempts to do so have also failed”). Hence, lessons learned from small animals such as the mice studies could not recapitulate the ability to deliver adequately in humans.
Kattenhorn et al (Adeno-Associated Virus Gene Therapy for Liver Disease, Human Gene Therapy 27(12): 947-961, November 28, 2016) taught concerns for translation lead to extensive analysis of the effects on clinical use. The use of AAV after initial promising results went on hiatus (pg 947, col. 2, “clinical hiatus in the field”) as the animal models were deficient (pg 953, col. 2, “Although animal models predicted many aspects of the human immune response…, they largely failed to predict responses to AAV capsid”; “Work done in nonhuman primates has not met with any additional success”). This emphasizes that the challenge in humans is to maintain the efficiency of delivery and expression while minimizing any pathogenicity of the virus from which the vector was derived. Eventually, the use of AAV is serotype-dependent (e.g. pg 950, col. 1), organ and concentration dependent. The inability to develop an adequate means of overcoming humoral responses, neutralizing antibody, inactivation of transgene expression, shedding and refractory cells limits the successful means by which the nucleic acid can be administered.
Greenberg (Gene Therapy for heart failure, Trends in Cardiovascular Medicine 27: 216-222, 2017) is considered relevant prior art for taught that despite success in experimental animal models, translating gene transfer strategies from the laboratory to the clinic remains at an early stage (Abstract). The success of gene therapy depends on a variety of factors that will ultimately determine the level of transgene expression within the targeted cells. These factors include the vector used for delivery, the method and conditions of delivery of the vector to the [target tissue], the dose that is given and interactions between the host and the vector that alter the efficiency of transfection of [target] cells (e.g. pg 217, col. 1). Failure of therapeutic results may arise because the vector DNA levels were at the lower end of the threshold for dose-response curves in pharmacology studies, and/or only a small proportion of target cells were expressing the therapeutic transgene (e.g. pg 220, col. 1). Although the use of AAVs for gene therapy is appealing, additional information about the best strain of AAVs to use in human patients is needed. Experience indicates that there is a need to carefully consider the dose of the gene therapy vector; however, this has proved to be difficult in early phase developmental studies due to the complexity and cost of such studies (e.g. pg 221, col. 1).
Maguire et al (Viral vectors for gene delivery to the inner ear, Hearing Research 394: e107927, 13 pages, doi.org/10.1016/j.heares.2020.107927, 2020) is considered relevant post-filing art for taught that despite the progress with AAV vectors in the inner ear, little is known regarding the mechanism of transduction of specific cells by AAV within the cochlea (e.g. pg 2, col. 2). There are limitations to what experiments in mice can tell us about the true translation potential of a new therapeutic (e.g. pg 8, col. 2), e.g. species-related physiological differences between mice and humans (e.g. pg 9, col. 1). The AAV dosage is a significant factor in achieving transduction of the target cell, as insufficient dosage may achieve no transduction of the target cells (e.g. pg 9, col. 2).
In conclusion, the specification fails to provide any guidance as to how an artisan would have dealt with the art-recognized limitations of the claimed method. Those of ordinary skill in the art would immediately recognize that the instant specification fails to establish the nexus between the generically recited genus of cholestatic diseases and injuries and generically recited method step of introducing at least one expressible coding region of human TGFBR1 into a hepatocyte of a human patient, and necessarily and predictably achieve a real-world result inducing transdifferentiation of the hepatocyte into a mature cholangiocyte.
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 1, 6-11, 13, 15, 19, and 53 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 recites: a method of inducing transdifferentiation of a hepatocyte into a mature cholangiocyte comprising introducing at least one expressible coding region of human Transforming Growth Factor Beta Type I Receptor (TGFBR1) into the hepatocyte of a human patient with a cholestatic disease or cholestatic injury under conditions where the expression of the at least one expressible coding region is greater than the wild- type level of expression in the hepatocyte, thereby inducing transdifferentiation of the hepatocyte into a mature cholangiocyte.
As written, it is unclear whether the introduction of TGFBR1 into hepatocytes requires the expression of the at least one expressible coding region to be greater than the wild- type level, or whether the expression of the at least one expressible coding region being greater than the wild- type level is a result of the method step of introducing the at least one expressible coding region of TGFBR1 into the hepatocyte (e.g., is greater than wild-type expression a condition or a result?). It would be remedial to clarify as such (e.g., the recitation “under conditions” causes confusion). For examination purposes, the claim language is interpreted to read on greater than wild-type expression being a condition or a result.
Claim 53 recites: The method of claim 1, wherein the at least one expressible coding region encodes a constitutively active form of human TGFBR1 and wherein the transdifferentiation occurs in the absence of Notch signaling. This recitation is unclear because as written in claim 1, inducing transdifferentiation is a result of the claimed method, not an active method step. As such, how would one carry out transdifferentiation under the condition of the absence of Notch signaling? (e.g., the recitation of “occurs in the absence of Notch signaling” does not structurally modify/further limit the active method step of introducing TGFBR1). It would be remedial to clarify in the claim language how occurring in the absence of Notch signaling modifies the active method step, not the result (i.e., function) of the claimed method. For examination purposes, the recitation “transdifferentiation occurs in the absence of Notch signaling” is not interpreted to further limit the structure of the claimed method, and instead further defines the function.
Response to Arguments
Applicant's arguments filed 06/03/2026 have been fully considered but they are not persuasive.
Regarding the 112(a) written description rejection, Applicant argues that Example 8 of the specification demonstrated the inventors had possession of the invention. This argument is not persuasive because the Examiner discusses Example 8 in the 112(a) rejection and sets forth why this singular working example is not sufficient. The Applicant fails to respond the issues previously set forth.
The Applicant does clarify in the specification where the dosage used in Example 8 can be found. However, teaching one exemplary dose does not sufficiently prove possession of the generically recited claimed method (e.g., no dosage). Additionally, the Applicant fails to expand on how [0043], [0044], and [0050] provide “ample guidance” on routes, doses, and formulation.
The Applicant does clarify where in the specification there is guidance for human TGFBR1 being used.
The Applicant argues that the functional condition “under conditions where the expression level of the at least one expressible coding region is greater than the wild-type level of expression in the hepatocyte”. As noted in the 112(b) rejection above, it is unclear how this recitation is intended to further limit the claimed method. How would an artisan know how to further limit the structure of the promoter based on this recitation alone, when no promoter is even recited in the base claim?
Regarding the 112(a) enablement rejection, Applicant argues that Example 8 provides sufficient information to one of ordinary skill in the art such that undue experimentation is not required, and that the Wands enablement factors leads to the conclusion that the claims are enabled. The Applicant fails to respond to the issues raised by the examiner upon this issue in the rejection and distinctly point out why there is no undue experimentation and why the Wands factors, which were outlined by the examiner, lead to enablement. Further, the Applicant fails to distinctly point out how an artisan would determine the “appropriate promoters, vectors, and routes of administration” (the Examiner notes that the claim language does not specify vectors as the method of introduction) without undue experimentation based on Example 8 alone. How does one working example for example, involving injecting AAV8-EF1alpha-caTGFBR1 into the tail vein of mice, lead to the enablement of successfully inducing transdifferentiation in vivo in human hepatocytes? Although the gene therapy references cited by the Examiner are not specific to TGFBR1, that does not discount their relevance to the claimed method. How are the challenges of gene therapy delivery not related to the claimed invention, which involves introducing (e.g., delivering) TGFBR1 (e.g., a gene) to the hepatocyte of a human with a cholestatic disease or injury (e.g., acting as a therapeutic)?
The Applicant arguments regarding the 103 rejection previously set forth are found to be persuasive. In view of the claim amendments and these arguments, the 103 rejection has been withdrawn.
Conclusion
No claims are allowed.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to ALLISON M JOHNSON whose telephone number is (703)756-1396. The examiner can normally be reached Monday-Friday 9am-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, Tracy Vivlemore can be reached on (571) 272-2914. 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.
/ALLISON MARIE JOHNSON/Examiner, Art Unit 1638
/ROBERT M KELLY/Primary Examiner, Art Unit 1638
Prosecution Insights