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 .
Election/Restrictions
Applicant's election with traverse of Group I (claims 1-7) in the reply filed on 10/22/2025 is acknowledged. The traversal is on the ground(s) that the elected invention (cell culture medium) in Group I is used in the nonelected method of Group II, therefore the claims could be examined together without imposing a serious search burden.
This is not found persuasive because Applicant traversed the restriction asserting that there would be no burden on the examiner in examining all of the claims at once.
Burden is not a consideration in a finding of lack of inventive unity; rather, according to M.P.E.P. §1850, the only consideration is whether the inventions share a special technical feature. The discussion of unity of invention under the Patent Cooperation Treaty Articles and Rules as it is applied as an International Searching Authority, International Preliminary Examining Authority, and in applications entering the National Stage under 35 U.S.C. 371 as a Designated or Elected Office in the U.S. Patent and Trademark Office is covered in M.P.E.P. §1850 and is dictated by PCT Rules 13.1 and 13.2. See M.P.E.P. §801.
The requirement is still deemed proper and is therefore made FINAL.
Claims 1-15 are pending.
Claims 8-15 are withdrawn from further consideration pursuant to 37 CFR 1.142(b), as being drawn to a nonelected Group, there being no allowable generic or linking claim.
Claims 1-7 are examined on the merits.
Claim Rejections - 35 USC § 112(a)
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 and 4-7 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.
Regarding claim 1: The claim recites a poloxamer with a polypropylene oxide block <700g/mol. This is interpreted as a polypropylene oxide block that has a molecular weight from 0-700 g/mol.
Table 1 of the instant specification teaches 23 examples of poloxamers, 10 of which are in the required molecular weight range for the PPO bock, below 700 g/mol. Table 1 teaches poloxamers ranging from 327 g/mol PPO and higher, but there are no examples of species below 327 g/mol.
Thus the species of poloxamer taught by the instant specification are not sufficient to demonstrate that Applicant had possession of the broad genus of poloxamers with a PPO oxide block of 700g/mol or less with an ethylene oxide percentage of >45%.
Wilson et al (WO 2019/125783 A1) teach poloxamers, especially poloxamer 188, are used in cell culture media processes and the addition of poloxamers to cell culture media improves cell viability (p1 [0003])
Wilson teach a poloxamer has the general formula of formula I (p2), shown below, in which x and z vary independently:
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178
530
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Wilson teach Y is ~15-26 and x+z is 81-100 with an average molecular weight of 6,000 g/mol – 8,000 g/mol (p3 [008]). Wilson further teach a negative relationship between peak molecular weight and poloxamer performance, which predicts lower molecular weight poloxamer 188 will have better performance in cell culture media (Figure 4, p4 [0014]). Wilson further teach one might try to improve poloxamer performance in cell culture by providing a low average molecular weight poloxamer (p4 [0017]).
No examples of poloxamers with a PPO block molecular weight of less than 300 g/mol are found in the art.
M.P.E.P. §2163 recites, “The written description requirement for a claimed genus may be satisfied through sufficient description of a representative number of species by actual reduction to practice, reduction to drawings, or by disclosure of relevant, identifying characteristics, i.e., structure or other physical and/or chemical properties, by functional characteristics coupled with a known or disclosed correlation between function and structure, or by a combination of such identifying characteristics, sufficient to show the applicant was in possession of the claimed genus…when there is substantial variation within the genus, one must describe a sufficient variety of species to reflect the variation within the genus.”
While the instant specification and art teach some specific examples of cell culture media comprising poloxamers, and poloxamers are described in the art, there is insufficient guidance for all poloxamers with a PPO block of < 700 g/mol and an EO% of >45%. No poloxamers are disclosed in either the art or the instant specification with a PPO block below 327 g/mol.
The gap between the limited number of structures corresponding poloxamers with a PPO block of < 700g/mol and EO percentage of >45% as described in the instant specification and art compared to the all poloxamer structures with a PPO block of < 700g/mol and EO percentage of >45%. Given this large gap, the specification fails to support the broad genus of “poloxamers with a PPO block of < 700g/mol and EO percentage of >45%” as claimed such that one skilled in the art can reasonably conclude the inventor had possession of the claimed invention.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
Claims 1-4 and 7 are rejected under 35 U.S.C. 103 as being unpatentable in view of Moreira et al (J Chem Tech Biotechnol (1995) 62;1-14) in view of Wilson et al (WO 2019/125783 A1), and as evidenced by Zarrintaj et al (Acta Biomaterialia (2020) 110;37-67), Gibco(2026) (DMEM formulation sheet [online] Gibco [retrieved on 02/12/2026]. Retrieved from the Internet: https://www.sigmaaldrich.com/US/en/technical-documents/technical-article/cell-culture-and-cell-culture-analysis/mammalian-cell-culture/dulbecco-modified-eagle-medium-formulation?srsltid=AfmBOoqecDsAS3NgBWp_SwcmJ93R_p22HbwY3lj6IfI4s6VsG4YwHcs-) and Wei et al (Scientific Reports (2016) 6:31175;1-6).
Regarding claims 1-3: Moreira teach methods for large scale culture of animal cells (abstract). Moreira teach cell culture media with and without Pluronic F-68 (also known as poloxamer 188) (p2 col2 ¶6). Moreira teach that the addition of surfactants such as Pluronic F-68 is required to protect cells from bubbles (p2 col2 ¶2).
Moreira do not teach the poloxamer has a PPO block of <700 g/mol.
Wilson teach poloxamers compositions for use as a shear protectant in cell culture (abstract). Wilson further teach the addition of poloxamers, especially Poloxamer 188, to cell culture media improves cell viability significantly (p1 [003]). Wilson teach that poloxamers with lower numbers of PPO (and therefore lower PPO block molecular weight) will have better performance in cell culture (Figure 1).
Wilson teach the structure of poloxamers has the general formula I, shown below:
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135
505
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Wilson further teach that x and z independently range preferably from 5-150 and y preferably ranges from 15-67 (p2 [0004]).
While Wilson do not explicitly disclose a poloxamer with a PPO block of <700 g/mol, Wilson do disclose low average molecular weight poloxamer provides superior performance and that it is possible to manufacture low average molecular weight poloxamer according to specification (p5 [0027]).
It would have been obvious to one of ordinary skill in the art to adapt the cell culture media comprising a poloxamer of Moreira by using a poloxamer with a PPO block with a low molecular weight as taught by Wilson.
One of ordinary skill in the art would have been motivated to modify the cell culture media comprising a poloxamer as taught by Moreira by using a poloxamer with a PPO block of low molecular weight as taught by Wilson because Wilson teach poloxamers with lower PPO numbers have a reduced decrease in cell culture performance (improved performance).
One would have had a reasonable expectation of success because Moreira teach use of Pluronic F-68 and that use of the Pluronic is required to protect cells from bubbles (p2 col2 ¶2).
Regarding claim 4: The teachings of Moreira are discussed supra. Moreira also teach studies are performed with and without 0.2% w/v Pluronic F-68 in cell culture medium (p3 col1).
One of ordinary skill in the art would understand 0.2% w/v is equivalent to 2 g/L and thus reads on “the poloxamer in an amount between 0.1 to 10g/L”.
MPEP 2131.03 reads “"[W]hen, as by a recitation of ranges or otherwise, a claim covers several compositions, the claim is ‘anticipated' if one of them is in the prior art." Titanium Metals Corp. v. Banner, 778 F.2d 775, 227 USPQ 773 (Fed. Cir. 1985)”
Regarding claim 7: The teachings of Moreira are discussed supra. Moreira further teach the cell culture medium is Dulbecco’s modified Eagle’s medium (DMEM) supplemented with fetal calf serum (p3 ¶2). As discussed below, DMEM and fetal calf serum (also known as FBS) comprise the components required by the instant claim.
As evidenced by the Gibco(2026) DMEM formulation sheet, DMEM contains one or more of the following: a saccharide (glucose), amino acids (L-arginine), vitamins (folic acid), salts (sodium chloride), buffer components (sodium phosphate monobasic) and co-factor (thiamine).
As evidenced by Wei, fetal calf serum is a source of nucleic acid components such as mRNAs (abstract).
Thus the teachings of Moreira and Wilson render obvious the invention as claimed.
Claims 5-6 are rejected under 35 U.S.C. 103 as being unpatentable over Moreira et al (J Chem Tech Biotechnol (1995) 62;1-14) in view of and Wilson et al (WO 2019/125783 A1), as applied above to claims 1-4 and 7, and further in view of Rayner-Brandes et al (WO 2015/003773 A1).
Regarding claims 5-6: The teachings of Moreira are discussed supra. Moreira do not teach the cell culture medium is a chemically defined medium or that the medium is a dry powder.
Rayner-Brandes teach cell culture media comprising polymer components (abstract). Rayner-Brandes teach that the cell culture medium is a chemically defined cell culture medium that is dry powder (claims 1 and 7 of Rayner-Brandes).
It would have been obvious to one of ordinary skill in the art to adapt the cell culture medium of Moreira by using a chemically defined culture medium or a medium that is dry powder as taught by Rayner-Brandes.
One of ordinary skill in the art would have been motivated to modify the culture medium as taught by Moreira with the teachings of Rayner-Brandes because Rayner-Brandes teach poorly chemically defined media is poorly characterized and difficult to manufacture with consistent quality (p2 ln24-30). Rayner-Brandes also teach one would be motivated to use dry powder medium because liquid cell culture media has reduced shelf life and has difficulties for shipping and storage (p3 ln 1-5).
One would have had a reasonable expectation of success because Rayner-Brandes disclose many cell culture media are offered as finely milled dry powder mixtures, and chemically defined media is easier to manufacture with consistent quality, and thus the results would have been predictable.
Thus the teachings of Moreira, Wilson and Moreira and Rayner-Brandes render obvious the invention as claimed.
Conclusion
No claims are allowed.
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/ANDREA LYNNE MORRIS SPENCER/Examiner, Art Unit 1631
/TAEYOON KIM/Primary Examiner, Art Unit 1631