Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined pursuant to the first inventor to file provisions of the AIA .
DETAILED ACTION
Status of the Claims
Applicants filed claims 1 – 7 with the instant application on 29 January 2025. In a Preliminary Amendment filed on 14 April 2025, Applicants canceled claims 1 – 7 and added new claims 8 - 25. Consequently, claims 8 – 25 are available for substantive consideration.
Information Disclosure Statement
The Examiner has considered the Information Disclosure Statements (IDS’s) filed 14 April 2025 and 13 March 2026, which are now of record in the file.
Rejections Pursuant to 35 U.S.C. § 103
The following is a quotation of 35 U.S.C. § 103 that 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 of this title, 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 set forth in Graham v. John Deere Co., 383 U.S. 1, 148 USPQ 459 (1966), that are applied 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 absent any evidence to the contrary. Applicants are advised of the obligation pursuant to 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 8 – 25 are rejected pursuant to 35 U.S.C. § 103, as being obvious over WO 2019/232589 to Dehghani, F. and I. Avitehrani, published 12 December 2019, identified on the Information Disclosure Statement (IDS) filed 14 April 2025, cite no. 019 (FOR) (“Dehghani WO ‘589, in view of US 2019/0083681 to Bhumiratana, S., et al, published 21 March 2019, identified on the IDS filed 14 April 2025, cite no. 010 (USPAT) (“Bhumiratana ‘134”), US 2010/0168798 A1 to Clineff, T., et al., published 1 July 2010 (“Clineff ‘798”), and WO 99/34772 A1 to Winston, A. and N. Usen, published 15 July 1999, identified on the IDS filed 14 April 2025, cite no. 013 (FOR) (“Winston WO ‘772”).
The Invention as Claimed
Applicants claim a method of implanting a bioresorbable putty implant into a bone implant site in a patient in need thereof, the method comprising the steps of heating an implant to provide the implant in a putty state; applying the implant in the putty state to the bone implant site; and allowing the implant in the putty state to cool to harden the implant; wherein the implant comprises poly(propylene carbonate) (PPC) with a porosity of 10 – 90%, and about 20% to about 30% by weight of a ceramic, such as calcium phosphate, hydroxyapatite, or bioglass 45s5, wherein the ceramic is in the form of particles, fibers, or whiskers, wherein the ceramic has a particle size of 1 µm to 20 µm, wherein the bioresorbable putty implant comprises a bioresorbable carbohydrate filler, such as corn or maize starch at relative loadings of about 1 % to about 40%, or 20 – 40% by weight, with particle sizes of 5 µm to 30 µm, wherein the bioresorbable putty implant is in a moldable putty state at about 45° C and a hardened state at about 37° C, wherein the bioresorbable putty implant is a non-load bearing implant, and wherein the bioresorbable putty implant is ==used for distal femoral osteotomy, high tibial osteotomy, pediatric osteotomies, proximal humerus fractures, tibial plateau fractures, bone tumors and cyst, cancellous fractures, osteolysis total joints, or bone-soft tissue reconstruction.
The Teachings of the Cited Art
Dehghani WO '589 discloses implants fabricated from a poly(propylene carbonate) and starch blend (PPC-starch), wherein the bioactivity and mechanical stiffness of PPC-starch blends was increased by the addition of bioglass microparticles (10% w/w) (see Abstract), wherein the addition of bioceramics is known to typically enhance osseointegration of implants (see p. 4, II. 3 - 4), wherein the combination of these biodegradable polymers with bioglass could produce a superior biomaterial that addresses certain shortfalls of currently available polymers (see p. 6, II. 5 - 7), wherein a hot melt compression technique was developed for the preparation of the blends of PPC-starch-bioglass (see p. 6, I. 8), wherein the bioactivity and stiffness of PPC-starch blends is increased by the addition of bioglass microparticles (at 10% w/w), as shown by in vitro osteoblast differentiation assay and mechanical testing (see p. 7, II. 29 - 31), wherein, in a rat knee implantation model, PPC-starch-bioglass screws inserted into the distal femur show osseointegration with no localized adverse effects after 3 and 12 weeks (see p. 7, II. 3 - 5), wherein the mechanical properties of a PPC-starch blend rival those of biodegradable aliphatic polyesters and, depending on the relative concentrations of PPC and starch in the blend, can be tuned for particular purposes (bending strength, toughness, rigidity, compressibility) (see p. 7, II. 13 - 16), wherein it is preferable to include a bioactive material, such as bioglass, which releases ions that promote the growth of bone (see p. 7, II. 22 - 24), wherein the composite comprises a blend of poly(propylene carbonate) (PPC) and starch, and a biocompatible ceramic material selected from hydroxyapatite (HA), calcium phosphates, and silica (SiO₂) based bioactive glass (see p. 8, II. 2 - 3), wherein the bioglass particles have an average particle size of 10 - 200 µm (see p. 10, II. 20 - 22), with a majority below 125 µm (see p. 10, II. 30 - 32), wherein the alkaline phosphatase (ALP) activity was found to increase in proportion to the amount of bioglass (from 0 to 10% w/w) included in the blend (see p. 13, II. 8 - 10), and wherein, in an in vivo biocompatibility and osseointegration in a knee implantation model, after 12 weeks of implantation, nearly 40.05 ± 0.79 % of the surface area of PPC/starch/bioglass samples were covered by new bone, as compared to a value of only 33.50 ± 0.94 % for PLA only constructs (see p. 29, II. 28 - 30). The reference does not expressly disclose implanting methods comprising heating an implant before implantation, and allowing the heated implant to cool to a hardened state, or implants wherein the PPC has a porosity of 10 – 90%, or implants with 45s5 as the bioglass, or implants comprising corn starch as the filler. These deficiencies are remedied by the teachings of Bhumiratana ‘681, Clineff ‘798, and Winston WO ‘772.
Bhumiratana ‘681 discloses porous polymer materials (or scaffolds), and more particularly to a polymer-ceramic composite having interconnected pores and a porosity of about 50% to 90%, wherein the scaffolds are bioresorbable and exhibit advantageous mechanical properties that mimic those found in natural bone (see Abstract), wherein the scaffolds optionally comprise a bioactive agent, such as mesenchymal stem cells (see ¶[0006]), wherein the porous polymeric scaffolds are prepared by heating a mixture comprising a biodegradable polymer, an inorganic additive (or ceramic material), and a porogen, compressing the heated mixture at a pressure of about 10 MPa to about 110 MPa, cooling the compression to form a bulk substrate, selectively removing a material from the bulk substrate to afford a shaped substrate, removing the porogen from the shaped substrate to result in the porous scaffold having a desired shape (see ¶¶[0008] – [0012]), wherein the scaffolds comprise a highly porous and biocompatible material, comprising a bioresorbable polymer and an inorganic additive, such as tricalcium phosphate, and has interconnected pores throughout the structure (see ¶[0023]), wherein the scaffold is sufficiently porous to allow, for example, seeding and growth of cells, such that the size of the pores can be adjusted to optimize cell survival and proliferation with pores that are at least about 50 µm to at least about 850 µm in diameter (see ¶[0033]), wherein the porosities of the scaffolds are at least about 30% to at least about 90% (see ¶[0037]), with an average pore size distribution of less than about 200 µm (see ¶[0042]).
Clineff ‘798 discloses bioactive implants comprising bioactive composites of polymer and glass (see Abstract), wherein the bioactive composites comprise a bioactive glass, such as 45S5, mixed with a polymer to produce a homogenous composite (see ¶[0005]), wherein the biocompatible polymer is a synthetic polymer (see ¶[0106]), wherein the biocompatible polymer may have a particle size of from about 4 µm to about 4,000 µm (see ¶[0108]), wherein, by incorporating bioactive glass, with particles in the size range of about 50 to about 300 µm, into the polymer matrix, a composite material is formed which, when implanted, elicits a bioactive reaction and leads to bone formation and direct bone apposition onto the surface of the implant, usually without intervening fibrous tissue (see ¶[0109]), wherein the bioactive glass component may also be in the form of fibers, whiskers or strands (see ¶[0118]), wherein the bioactive glass is present in an amount of about 5 to 50% by weight of the composite material (see ¶[0121]), wherein the composite material may be used in a variety of orthopedic procedures involving bone repair and restoration (see ¶[0199]), wherein results of mechanical push out testing demonstrate that all formulations of the bioactive glass-containing composite had at least two times greater interfacial shear strength as compared to the 100% polymer control at 12 and 24 weeks, and at 12 weeks, almost all bioactive composite formulations had significantly stronger bone-bonding than 100% polymer (p<0.05), while at 24 weeks, the 70/30 and 60/40 bioactive
composite materials exhibited significantly greater interfacial shear strength as compared to 100% polymer (see ¶[0238]).
Winston WO ‘772 discloses solid products for remineralizing subsurface lesions comprising a calcium phosphate component mixed in a carrier, wherein the products can be used in an implant (see Abstract), wherein the products further comprise a solid substrate (see p. 13, ll. 2 – 10), wherein the solid products provide for a means for remineralizing teeth and/or mineralizing dentin tubules at desired specific sites and at the same time provide an extended release of calcium and phosphate salts from the solid product (see p. 15, ll. 28 – 32), and wherein the carrier component of the solid products of can be any suitable gum, starch, including corn starch, wax or polymeric material which allow for the release the calcium and phosphate salts, preferably simultaneously, into the water and/or saliva (see p. 28, ll. 9 – 17).
Application of the Cited Art to the Claims
It would have been prima facie obvious before the filing date of the claimed invention to prepare tissue implants for implantation into a tissue injury or defect, wherein the implants fabricated from a poly(propylene carbonate) and starch blend (PPC-starch), wherein the bioactivity and mechanical stiffness of PPC-starch blends was increased by the addition of bioglass microparticles (10% w/w) (see Abstract), wherein a hot melt compression technique was developed for the preparation of the blends of PPC-starch-bioglass (see p. 6, I. 8), wherein the bioactivity and stiffness of PPC-starch blends is increased by the addition of bioglass microparticles (at 10% w/w), wherein, in a rat knee implantation model, PPC-starch-bioglass implants inserted into the distal femur show osseointegration with no localized adverse effects after 3 and 12 weeks, wherein the mechanical properties of a PPC-starch blend rival those of biodegradable aliphatic polyesters and, depending on the relative concentrations of PPC and starch in the blend, can be tuned for particular purposes (bending strength, toughness, rigidity, compressibility), wherein inclusion a bioactive material, such as bioglass, leads to the release of ions that promote the growth of bone, wherein the composite comprises a blend of poly(propylene carbonate) (PPC) and starch, and a silica (SiO₂) based bioactive glass, wherein the bioglass particles have an average particle size of 10 - 200 µm, with a majority below 125 µm, wherein alkaline phosphatase (ALP) activity was found to increase in proportion to the amount of bioglass (from 0 to 10% w/w) included in the blend, and wherein, in an in vivo biocompatibility and osseointegration in a knee implantation model, after 12 weeks of implantation, nearly 40.05 ± 0.79 % of the surface area of PPC/starch/bioglass samples were covered by new bone, as compared to a value of only 33.50 ± 0.94 % for PLA only constructs, as taught by Dehghani WO '589, wherein the polymer-ceramic composites have interconnected pores and a porosity of about 50% to 90%, wherein the porous polymeric scaffolds are prepared by heating a mixture comprising a biodegradable polymer, an inorganic additive (or ceramic material), and a porogen, cooling the compression to form a substrate, removing the porogen from the substrate to result in the porous scaffold, wherein the scaffold is sufficiently porous to allow, for example, seeding and growth of cells, such that the size of the pores can be adjusted to optimize cell survival and proliferation with pores that are at least about 50 µm to at least about 850 µm in diameter, as taught by Bhumiratana ‘681, wherein the bioactive composites comprise a bioactive glass, such as 45S5, mixed with a polymer to produce a homogenous composite, wherein the biocompatible polymer is a synthetic polymer, wherein, by incorporating 45s5 bioactive glass, with particles in the size range of about 50 to about 300 µm, into the polymer matrix, a composite material is formed which, when implanted, elicits a bioactive reaction and leads to bone formation and direct bone apposition onto the surface of the implant, usually without intervening fibrous tissue, wherein the bioactive glass is present in an amount of about 5 to 50% by weight of the composite material, wherein results of mechanical push out testing demonstrate that all formulations of the bioactive glass-containing composite had at least two times greater interfacial shear strength as compared to the 100% polymer control at 12 and 24 weeks, and at 12 weeks, almost all bioactive composite formulations had significantly stronger bone-bonding than 100% polymer (p<0.05), while at 24 weeks, the 70/30 and 60/40 bioactive composite materials exhibited significantly greater interfacial shear strength as compared to 100% polymer, as taught by Clineff ‘798, wherein the carrier component of the composite materials includes corn starch, a material that allows for the release the calcium and phosphate salts from the ceramic/bioglass component, preferably simultaneously, into the water and/or saliva, as taught by Winston ‘772.
One of ordinary skill in the art, with a reasonable expectation of success in so doing, by the express teachings of Bhumiratana ‘681 to the effect that the composite scaffolds are sufficiently porous to allow the seeding and growth of cells, such that the size of the pores can be adjusted to optimize cell survival and proliferation with pores that are at least about 50 µm to at least about 850 µm in diameter, by the teachings of Clineff ‘798 to the effect that, by incorporating 45s5 bioactive glass, with particles in the size range of about 50 to about 300 µm, into the polymer matrix, a composite material is formed which, when implanted, elicits a bioactive reaction and leads to bone formation and direct bone apposition onto the surface of the implant, usually without intervening fibrous tissue, wherein results of mechanical push out testing demonstrate that all formulations of the bioactive glass-containing composite had at least two times greater interfacial shear strength as compared to the 100% polymer control at 12 and 24 weeks, and at 12 weeks, almost all bioactive composite formulations had significantly stronger bone-bonding than 100% polymer (p<0.05), while at 24 weeks, the 70/30 and 60/40 bioactive composite materials exhibited significantly greater interfacial shear strength as compared to 100% polymer, and by the disclosure of Winston WO ‘772 establishing the utility of corn starch to create additional porosity by the leaching out of the starch.
With respect to those claims reciting quantitative ranges, such as claims 12, 17, and 20 (particle size), claims 14 and 15 (relative mass loadings), and claim 22 (porosity), the Examiner notes that the cited references do not explicitly disclose quantitative ranges that are exactly congruent with the claimed ranges. However, it is the Examiner’s position that the cited art teaches a range of quantitative limitations that significantly overlap with the claimed ranges and, as such, would render the claimed invention obvious. See MPEP § 2144.05. “In the case where the claimed ranges ‘overlap or lie inside ranges disclosed by the prior art’ a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976).”
With respect to claims 24 and 25, which claims recite limitations directed to the bioresorbable putty implant being a non-load bearing implant (claim 24), and the possible clinical uses of the composite materials in various surgical procedures (claim 25), it is the Examiner’s position that such limitations are directed to intended uses of the implant material, and are not specifically tied to compositional or structural characteristics that correlate to the proposed uses. Statements of intended use or function normally are not given patentable weight because they are not structurally limiting. Cf. Cochlear Bone Anchored Sols. AB v. Oticon Med. AB, 958 F.3d 1348, 1354-55 (Fed. Cir. 2020).
In light of the forgoing discussion, the Examiner concludes that the subject matter defined by claims 8 – 25 would have been obvious within the meaning of 35 USC § 103.
NO CLAIM IS ALLOWED
CONCLUSION
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/DANIEL F COUGHLIN/
Examiner, Art Unit 1619
/DAVID J BLANCHARD/ Supervisory Patent Examiner, Art Unit 1619
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