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 .
Election/Restrictions
Applicant's election with traverse of claims 1-11, 13-25, 27-34 in the reply filed on 2/15/25 is acknowledged. The traversal is on the ground(s) that a search for non-porous sheets would result in a prior art for porous prior art as there is overlap in the relative prior art. This is not found persuasive because the search of the resulting sheets require different materials and structure physically. Non-porous sheets would not swell similarly to those sheets that are porous.
The requirement is still deemed proper and is therefore made FINAL.
Claim Rejections - 35 USC § 103
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.
Claim(s) 1-11, 13-25, 27-34 is/are rejected under 35 U.S.C. 103 as being unpatentable over the combined disclosures of CN 107325307 A hereafter 301 in view of Tanaka et al (US 2013/0337227 A1 hereafter Tanaka), Tillman et al (The in vivo stability of electrospun polycaprolactone-collagen scaffolds in vascular reconstruction, Biomaterials, 30, 583-588, 2009 hereafter Tillman) and Shen et al (US 11,027,040 hereafter Shen).
307 discloses a non-fibrous film comprising a collagen, a polyester where the content of the polyester polymer is present in a ratio of 5: 1 relative to the collagen [Embodiment 1], meeting limitations of claim 1. The collagen is type I [0011], meeting the limitations of claim 2 and 3. The polyester can be polylactic acid (PLA) has a molecular weight from 20,000 to 300,000 and a, intrinsic viscosity from 0.3-2 dl/g [0009-0010], meeting limitations of claim 6-8. The non-fibrous film can be porous with pore below 10 microns [0009], meeting limitation of claim 9 and 10. Solvents for the formulation include trifluoroacetic acid [0018], meeting limitations of claim. The sheet can be crosslinked [Embodiments].
The reference, while disclosing a non-fibrous sheet, the reference is silent to the swelling rate of the film. The inclusion of collagen into biopolymers sheets that swell are known in the art as seen in the Tanaka.
Tanaka discloses a non-fibrogenesis collagen material [0017]. The sheet is crosslinked by glutaraldehyde [0065]. The sheet is swellable with a swelling ratio it at least 100% [0067-0068]. The sheet is porous with pores with a diameter at least 50 microns [0073-0074]. It would have been obvious to include the collagen of the Tanaka into the formulation of 307 as they solve similar problems.
The combination discloses a combination of a polyester and collagen into a non-fibrous sheet, but does not disclose the exact polyester of the instant claims. The use of specific polyester is well known in the art as seen in the Tillman study.
Tillman discloses a polycarprolactone-collagen scaffold for cells [abstract]. The PCL and collagen is present in a 50-50 ratio and the scaffold is useful for cell growth comprising vascular cells by comprising endothelial progenitor cells [abstract, pg. 584]. The scaffold is formed by preparing a solution comprising a solute, the polyester and the collagen, where the polyester is preset about 50% and the solute is a perfluorocarbon, followed by drying the solution (2.1). The PCL has an inherent viscosity of 1.77 dL/g [2.1]. The composite scaffold is crosslinked with glutaraldehyde solution for 6 hours [2.1] meeting limitations of claim 28-31. It would have been obvious to include these elements into the formulation of 307 as they solve the same problem.
The combination however is silent to the specific molecular weight of the polycaprolactone. The use of specific molecular weight polyesters is known in the art as seen in the Shen.
Shen discloses a porous film useful for tissue adhesion and healing comprising polycaprolactone (abstract, col. 1, lin. 35-62). The polycaprolactone has a molecular weight up to 800,000 (col. 1, lin. 63-67). The pores have a diameter as low as 10 microns (col. 2, lin. 25-30). The sheets are formed in a method where the polyesters are dissolved, in a solution, and dried to form a film (Examples). It would have been obvious to include these PCL into the combination as they provide a porous sheet that allows for improve cell growth (col. 9, lin. 30-57).
With these aspects in mind it would have been obvious to combine the prior art to form a stable non-fibrous scaffold for tissue growth and wound healing. It would have been obvious to combine the collagen of Tanaka into the formulation of 307 as they solve the same problem and provide sufficient swelling for cell growth. It would have been obvious to include the specific polyester of Tillman as it established the level of skill in the art regarding polyester and collagen sheets as grow scaffolds for cells in tissue sheets. It would have been obvious to include the specific high molecular weight PCL of Shen as the pores allow for improve cell growth. It would have been obvious to an artisan of ordinary skill in the art optimize the ratios and concentrations of the components of the formulation combination through routine experimentation. One of ordinary skill in the art would have been motivated to combine the prior art with an expected result of a stable cell sheet useful in wound healing.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to MICAH PAUL YOUNG whose telephone number is (571)272-0608. The examiner can normally be reached Monday through Friday, 9:00 am to 5:30 pm.
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/MICAH PAUL YOUNG/ Primary Examiner, Art Unit 1618