DETAILED ACTION
Status of claim rejections
The rejections of record under 35 USC 112(a) are withdrawn in view of Applicant’s amendment to the claims in the response filed 11/21/25.
The rejections of record under 35 USC 112(b) are withdrawn in view of Applicant’s amendment to the claims in the response filed 11/21/25.
The rejection of record under 35 USC 102 are modified in view of Applicant’s amendment to the claims in the response filed 11/21/25.
The rejection of record under 35 USC 103 against claim 41 is withdrawn. in view of Applicant’s amendment to the claims in the response filed 11/21/25. Please note that the rejection is recast using a new reference below.
The rejection of record under 35 USC 103 against claim 42 are maintained in view of Applicant’s amendment to the claims in the response filed 11/21/25.
Claim Interpretation
The claims as amended now recite “culturing said host cell in a suitable culture medium under conditions to effect expression of plasminogen from the first polynucleotide and PAI-1 from the second polynucleotide for at least 3 days, wherein the culturing produces a yield of plasminogen is at least 30 mg/L of cell culture.” The examiner has interpreted this limitation to encompass an intended result of the culturing step (see MPEP 211.04).
Modified Claim Rejections - 35 USC § 102/103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
(a)(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention.
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claims 1, 35, 39, 44, and 54-57 are rejected under 35 U.S.C. 102(a)(1)/(a)(2) as being anticipated, or in the alternative, under 35 U.S.C. 103 as obvious over Mulvihill (US 5648254 A; prior art of record).
Mulvihill teaches a method for producing plasminogen, comprising: introducing into a baby hamster kidney cell a first DNA sequence encoding plasminogen (providing a host cell comprising a first recombinant polynucleotide encoding plasminogen as in claim 1) and an additional DNA sequence encoding a protein selected from the group consisting of Arg(358) alpha-1-antitrypsin, α2 plasmin inhibitor and plasminogen activator inhibitor 1 (and a second recombinant polynucleotide encoding PAI-1 as in claim 1), wherein said DNA sequences are operably linked to transcriptional promoter and terminator sequences; culturing the cell under conditions which allow the first and additional DNA sequences to be expressed (culturing said host cell in a suitable culture medium under conditions to effect expression of plasminogen from the first polynucleotide and PAI-1 from the second polynucleotide as in claim 1); and isolating the plasminogen from the cell (see claim 1 and claim 14; Example 2(E)). Mulvihill further teaches use of a single vector (see col 2, lines 20-30; claim 1 and 3).
Further regarding claim 1, Mulvihill teaches culturing the cells for 10-25 days (i.e., at least 3 days as claimed) before quantification of plasminogen co-expression (see col 18, lines 45-60). Mulvihill does not explicitly teach the culturing produces a yield of 30 mg/L of cell culture. However, this limitation to encompass an intended result of the culturing step (see MPEP 211.04). As such, absent evidence to the contrary, the amount of plasminogen produced would flow from the teachings of the Mulvihill, which explicitly discloses the method steps as instantly claimed.
In the alternative, it would have been prima facie obvious to one of ordinary skill at the time of filing to use the method of Mulvihill with a reasonable expectation of successfully producing recombinant plasminogen from recombinant host cells. One of ordinary skill would have been motivated to do so because Mulvihill teaches the protein can be produced using recombinant vector transfection and culturing techniques.
Regarding claim 35, Mulvihill teaches providing polynucleotide encoding plasminogen and a second polynucleotide encoding PAI-1 (see Example 2(E); claim 14 and 15) where the polynucleotides are operably linked to a promoter (see claim 14) and transfecting a host cell with the polynucleotides (see Example 2(E); claim 14 and 15).
Regarding claim 39, Mulvihill teaches the use of Glu-plasminogen and Lys-plasminogen (see col 7, lines 18-20; col 17, lines 56-67).
Regarding claim 44, Mulvihill teaches that the host cell is a mammalian cell (see claim 1, 4, 6, 14, 15).
Regarding claim 54, Mulvihill teaches isolating plasminogen from the host cell (see claim 1 and 14).
Regarding claim 55-56, Mulvihill teaches “introducing the DNA sequences into the host cell may be through (a) cotransfection or cotransformation with multiple vectors, each containing a separate expression unit (i.e., monocistronic expression of each protein); or (b) transfection or transformation with a single vector containing multiple expression units” where “introducing may also be through transfection with a single vector containing a single expression unit transcribed into a polycistronic message” (i.e., at least bicistronic expression) (see col 2, lines 12-31).
Regarding claim 57, Mulvihill teaches preferred mammalian cells, including COS cells (see col 9, lines 9-10).
Accordingly, the claimed invention was anticipated by, or in the alternative, rendered prima facie obvious by the teachings of Mulvihill.
Maintained/Modified Claim Rejections - 35 USC § 103
First rejection
Claim 38 is rejected under 35 U.S.C. 103 as being unpatentable over Mulvihill as applied to claim 1, 35, 39, 44, and 54-57 above, and further in view of Busby et al (Expression of recombinant human plasminogen in mammalian cells is augmented by suppression of plasmin activity. J Biol Chem. 1991 Aug 15;266(23):15286-92; in IDS; hereinafter “Busby”; prior art of record).
As discussed above, claims 1, 35, 39, 44, and 54-57 were anticipated by the teachings of Mulvihill.
The difference between Mulvihill and the instant claims is that Mulvihill does not explicitly teach the method further comprises the step of admixing PAI-1 into the culture media.
However, Busby teaches expression of recombinant human plasminogen (a serine protease) in mammalian cells is augmented by suppression of plasmin activity (title, abstract). Busby also teaches that over-expression of human plasminogen can be cytotoxic to mammalian cells (see abstract). To overcome this, Busby teaches the expression of plasminogen in baby hamster kidney cells and removing as much plasminogen in the Dulbecco’s modified Eagle’s cell culture medium by including an alpha2-PI plasminogen inhibitor (see pg. 15287 col 1, paragraph 2; pg. 15287 col 2, paragraph 1). Busby teaches that the inclusion of the protease inhibitor into the cell culture medium allows for depletion of serum plasminogen, as a precaution against trace amounts of plasmin being generated in the media by plasminogen activators secreted by the cells and can prevent activation of recombinant plasminogen activator (pg. 15287 col 2, paragraph 1). Please note that Busby does not teach mixing PAI-1 specifically into the cell culture media. However, one of ordinary skill would have readily applied the teachings of Busby by mixing any plasminogen inhibitor in a cell culture medium, because one of ordinary skill would have been able to choose from a finite number of identified plasminogen inhibitors for the purpose of reducing plasmin activation with a reasonable expectation of success (see MPEP 2143).
Therefore, it would have been prima facie obvious to one of ordinary skill at the time of filing to modify the method of producing plasminogen in recombinant mammalian cells as taught by Mulvihill by mixing plasminogen inhibitor into the cell culture medium as taught by Busby to arrive at the claimed invention. As Mulvihill teaches method of producing plasminogen in mammalian cells and Busby teaches that plasminogen inhibitors can be mixed into the cell culture medium, one of ordinary skill would have been motivated to make the modification with a reasonable expectation of success. One of ordinary skill would have been motivated to make the modification because Busby teaches that mixing plasminogen inhibitor advantageously allows for depletion of serum plasminogen, as a precaution against trace amounts of plasmin being generated in the media by plasminogen activators secreted by the cells and can prevent activation of recombinant plasminogen activator.
Accordingly, the claimed invention was prima facie obvious to one of ordinary skill at the time of filing, especially in the absence of evidence to the contrary.
Second rejection
Claim 41 is rejected under 35 U.S.C. 103 as being unpatentable over Mulvihill as applied to claim 1, 35, 39, 44, and 54-57 above, and further in view of Cao et al (WO200220813).
As discussed above, claims 1, 35, 39, 44, and 54-57 were anticipated, or rendered obvious by the teachings of Mulvihill.
The difference between Mulvihill and the instant claims is that Mulvihill does not explicitly teach the plasminogen comprises, consists or consists essentially of the amino acid sequence as set forth in any one of SEQ ID NO: 2, or a sequence at least 95% identical thereto.
However, Cao teaches recombinant proteins including human plasminogen (see abstract). Cao teaches that the nucleic acid molecule is derived from that encoding human plasminogen as shown in Fig. 1, as well as a method of making a protein, including expression from nucleic acid encoding the recombinant protein which is conveniently be achieved by growing a host cell containing such a vector in culture, under appropriate conditions which cause or allow expression of the protein (see pg. 14). Cao teaches a plasminogen polypeptide which has 99.9% sequence identity to instant SEQ ID NO: 2 (see alignment below).
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Therefore, it would have been prima facie obvious to one of ordinary skill at the time of filing to modify the method of producing plasminogen in recombinant mammalian cells as taught by Mulvihill by using the plasminogen polypeptide sequence as taught by Cao to arrive at the claimed invention. As the claimed invention requires the production of plasminogen polypeptide from a host cell, one of ordinary skill would have been motivated to perform a simple substitution of one known element (the plasminogen polypeptide of Mulvihill) with another (the polypeptide sequence of Cao) with a reasonable expectation of success (production of plasminogen polypeptide from a host cell). One of ordinary skill would have been motivated to make the substitution because Cao teaches that the disclosed plasminogen polypeptide can be successfully produced from a recombinant host cell.
Accordingly, the claimed invention was prima facie obvious to one of ordinary skill at the time of filing, especially in the absence of evidence to the contrary.
Third rejection
Claim 42 is rejected under 35 U.S.C. 103 as being unpatentable over Mulvihill as applied to claim 1, 35, 39, 44, and 54-57 above, and further in view of Uniprot/SwissProt Accession No. PAI1_HUMAN (as disclosed/evidenced by Pannekoek et al (Endothelial plasminogen activator inhibitor (PAI): a new member of the Serpin gene family. EMBO J. 1986 Oct;5(10):2539-44; hereinafter “Pannekoek”); hereinafter “PAI”; prior art of record).
As discussed above, claims 1, 35, 39, 44, and 54-57 were anticipated by the teachings of Mulvihill.
The difference between Mulvihill and the instant claims is that Mulvihill does not explicitly teach the polynucleotide encoding PAI-1 comprises a nucleic acid sequence as set forth in SEQ ID NO: 4, or a sequence at least 90% identical thereto.
However, PAI teaches a sequence of PAI-1 that has 98.8% identity to instant SEQ ID NO: 4. As disclosed by Pannekoek, inhibition of plasminogen activators [both t-PA and urokinase (uPA)] by PAI is accomplished by the formation of a 1:1 complex of the inhibitor and the 'target' serine protease (see pg. 2539, col 2, paragraph 3). Pannekoek further discloses the PAI nucleic acid sequence, as well as its production and expression from transfected mammalian cells in recombinant expression plasmids (pg. 2540, col 1, Fig. 1; col 2, paragraph 3; Fig. 2(a)).
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Therefore, it would have been prima facie obvious to one of ordinary skill at the time of filing to modify the method of producing plasminogen in recombinant mammalian cells as taught by Mulvihill by using the PAI-1 nucleic acid sequence as taught by PAI to arrive at the claimed invention. As the claimed invention requires the production of plasminogen and PAI-1 from nucleic acid sequence in a host cell, one of ordinary skill would have been motivated to perform a simple substitution of one known element (the PAI-1 polynucleotide sequence of Mulvihill) with another (the PAI-1 polynucleotide sequence of PAI/Pannakoek) with a reasonable expectation of success (production of PAI-1 from nucleic acid sequence in a host cell). One of ordinary skill would have been motivated to make the substitution because PAI teaches that the disclosed polynucleotide can be used successfully to produce PAI-1 in a host cell.
Accordingly, the claimed invention was prima facie obvious to one of ordinary skill at the time of filing, especially in the absence of evidence to the contrary.
Response to Arguments
Applicant's arguments filed 11/21/25 have been fully considered but they are not persuasive. Note that the rejection using the previously cited Novokhatny reference has been withdrawn, such that any arguments drawn to that reference are moot.
On pg. 6-7, Applicant argues that Mulvihill does not disclose culturing a host cell to effect expression from the polynucleotides and does not disclose culturing for at least 3 days of culture that yields at least 30 mg/L.
In response, as set forth above, the examiner disagrees. As discussed in the 102/103 rejection above, Mulvihill teaches culturing the cells for 10-25 days (i.e., at least 3 days as claimed) before quantification of plasminogen co-expression (see col 18, lines 45-60). Mulvihill does not explicitly teach the culturing produces a yield of 30 mg/L of cell culture. However, this limitation to encompass an intended result of the culturing step (see MPEP 211.04). As such, absent evidence to the contrary, the amount of plasminogen produced would flow from the teachings of the Mulvihill, which explicitly discloses the method steps as instantly claimed.
On pg. 7-11, Applicant argues that Mulvihill provides no disclosure as to culture conditions, length, or expected yield of plasminogen, such that one of ordinary skill would not have had a starting point to optimize expression of recombinant plasminogen, or reasonable expectation of success in producing 30 mg/L plasminogen from culturing. Applicant argues that the data in Mulvihill is not quantifiable but urges that it is likely that the amount of protein produced by Mulvihill is likely less than 5 mg/L. Applicant also argues that Busby does not cure the deficiencies of Mulvihill because although Busby generally discloses production of recombinant plasminogen, there is no guidance as to culture conditions, length of time of co-culture. Applicant urges that Busby’s unpredictable nature of protein production based on cell type in Busby, one of ordinary skill would not have had a reasonable expectation of success and cites to data in the specification to support the argument.
In response, the examiner disagrees. First, as discussed in the 102/103 rejection above, Mulvihill teaches culturing the cells for 10-25 days (i.e., at least 3 days as claimed) before quantification of plasminogen co-expression (see col 18, lines 45-60). Mulvihill does not explicitly teach the culturing produces a yield of 30 mg/L of cell culture. However, this limitation to encompass an intended result of the culturing step (see MPEP 211.04). As such, absent evidence to the contrary, the amount of plasminogen produced would flow from the teachings of the Mulvihill, which explicitly discloses the method steps as instantly claimed. Second, Applicant’s argument about the likelihood of Mulvihill’s protein yield must be substantiated by empirical evidence. An argument by the applicant is not evidence unless it is an admission. Arguments presented by applicant cannot take the place of evidence in the record. See In re De Blauwe, 736 F.2d 699, 705, 222 USPQ 191, 196 (Fed. Cir. 1984); In re Schulze, 346 F.2d 600, 602, 145 USPQ 716, 718 (CCPA 1965); In re Geisler, 116 F.3d 1465, 43 USPQ2d 1362 (Fed. Cir. 1997) (see MPEP 2145(I)). Third, regarding Applicant;s arguments regarding the Busby reference, one of ordinary skill would have readily applied the teachings of Busby by mixing any plasminogen inhibitor in a cell culture medium, because one of ordinary skill would have been able to choose from a finite number of identified plasminogen inhibitors for the purpose of reducing plasmin activation with a reasonable expectation of success (see MPEP 2143).
Furthermore, the yield of plasminogen, seems to be the result of the cells/culture conditions used to express the polypeptides, as Applicant has previously conceded on record that yields from stably transfected cells suitable for large-scale expression are in the order of 80-100 mg/L cell culture versus general, transient expression. It is noted that the cell type utilized for expression can be any host cell as instantly claimed, CHO, HeLa, COS, or Vero cells (see instant claim 57), also taught by Mulvihill. The host cell types encompassed by the instant claims and the specific cells chosen for expression seem to be the result of routine optimization using standard laboratory techniques available at the time of filing. Thus, in view of the teachings of the prior art references, the claims are prima facie obvious and the rejection is maintained.
Conclusion
NO CLAIMS ALLOWED.
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure:
Alessi et al. (1988), Purification and characterization of natural and recombinant human plasminogen activator inhibitor-1 (PAI-1). European Journal of Biochemistry, 175: 531-540
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/G.C.R./Examiner, Art Unit 1651
/THOMAS J. VISONE/Supervisory Patent Examiner, Art Unit 1672