DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after 16 March 2013, is being examined under the first inventor to file provisions of the AIA .
Status of the Claims
Amendments to the Claims and Arguments/Remarks filed 30 March 2026, in response to the Office Correspondence dated 28 November 2025, are acknowledged.
The listing of Claims filed 30 March 2026, have been examined. Claims 1-16 are pending. Claim 1 are amended and are supported by the originally-filed disclosure and new claim 16 has been added.
Response to Amendment
The amendment filed has been entered. The applicant’s arguments regarding the non-obviousness of the claims have been fully considered. However, the arguments are unpersuasive for the reasons set forth below in the Response to Arguments.
Based on the amendment to claim 1 to recite, inter alia, that the ELAC threads of each phase are braided and include triaxial ELAC threads, and the ELAC threads of the first and second phases are crosslinked, the previous rejection of claims 1-15 under 35 USC § 103 is withdrawn, as the rejection can be further supported with additional prior art references.
Claims 1-15 and new claim 16 are rejected under 35 USC § 103, necessitated by amendment, as set forth below. In addition to the above, newly amended claim 1 and new claim 16 introduce new issues under 35 U.S.C. §112. Accordingly, new rejections under 35 USC § 112 for amended claim 1 (including dependent claims 2-16) and new claim 16 are made herein.
New Rejections
The following new rejections are made from the previous Office Correspondence dated 28 November 2025, as the applicant's amendment necessitated the new grounds of rejection presented below based on the amended/newly cited limitations.
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 1-16 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 “the ELAC threads of the first phase are braided and include triaxial ELAC threads; the ELAC threads of the second phase are braided and include triaxial ELAC threads; and the ELAC threads of the first and second phases are crosslinked.” The applicant cites support in ¶[0014], ¶[0053], ¶[0074] and Figs. 1 and 11(B). However, a review of these sections reveals no clear written description of both the first and second phases being simultaneously braided, both including triaxial threads, and both being crosslinked as an integrated biphasic scaffold. While individual components may be described, the combination as now claimed lacks adequate descriptive support.
More specifically, ¶[0014] describes a biphasic scaffold in general but does not describe braiding of both phases with triaxial threads, ¶[0053] describes braiding and triaxial threads but does not explicitly describe that both phases have this architecture, ¶[0074] describes crosslinking but not in the context of both phases being crosslinked with triaxial braiding, and Figures 1 and 11(B) show a biphasic scaffold but do not label or describe the thread-level architecture of both phases as braided triaxial.
Thus, the specification as originally filed does not reasonably convey to one of ordinary skill that the inventor possessed a scaffold wherein both phases independently have braided triaxial ELAC threads and are crosslinked. This is a new limitation added by amendment without adequate antecedent written description. Dependent claims 2-16 are included in this rejection because they do not cure the defect noted above.
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 Applicant regards as his invention.
Claims 1-16 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, regards as the invention.
Claim 1 uses the phrase “having a major surface” appears for both phases, but later recitation, “the calcium phosphate mineral of the first phase is distributed on the major surface of the first phase”, introduces ambiguity regarding whether each phase has a distinct major surface, both major surfaces are co-planar, or only one major surface is externally exposed. Accordingly, the claim fails to particularly point out and distinctly claim the subject matter regarded as the invention. Clarification is required. Dependent claims 2-16 are included in this rejection because they do not cure the defect noted above.
Claim 16 is also rejected as being indefinite independently. Claim 16 further introduces ambiguity by reciting “the major surfaces of the first and second phases form one side”. It is unclear whether the major surfaces of the two phases are coplanar and together constitute one common single continuous outer side, if only portions of each major surface form that side, or the phases are coextensive (e.g., the major surfaces are distinct but both face the same direction or the major surfaces are joined edge-to-edge to form a single planar side).
Moreover, the phrase “form one side” does not inform one of ordinary skill as to the structural arrangement with reasonable certainty. Given that the scaffold is biphasic and intended for osteotendinous repair (bone-to-tendon interface), it is unclear how two separate phases, each with its own major surface, can together form “one side” of the scaffold without additional structural explanation. This ambiguity renders the scope of claim 16 uncertain. Clarification is required.
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-AlA 35 U.S.C. § 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AlA) 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 1-16 are rejected under 35 U.S.C. § 103 as being unpatentable over Ramakrishna et al. (Tissue engineering a tendon-bone junction with biodegradable braided scaffolds. Biomater Res. 2019 May 16;23:11, hereinafter referred to as “Ramakrishna”) in view of Learn et al. (Woven collagen biotextiles enable mechanically functional rotator cuff tendon regeneration during repair of segmental tendon defects in vivo. J. Biomed Mater Res B Appl Biomater. 2019 Aug; 107(6): 1864-1876; electronically published 2018 Nov 28, hereinafter referred to as "Learn"), and in further view of Wang et al. (Regeneration of skeletal system with genipin crosslinked biomaterials. J Tissue Eng.; 11:20417314290974861; published 2020 Nov 29, hereinafter referred to as "Wang"), Wan et al. (US- 20200046872-A1; published 13 February 2020, hereinafter referred to as "Wan", and Ahn et al. (3D braid scaffolds for regeneration of articular cartilage. J Mech Behav Biomed Mater. 2014 Jun;34:37-46, hereinafter referred to as “Ahn”).
Ramakrishna teaches biphasic braided scaffold specifically for tendon-bone (osteotendinous) junction (see Title: "Tissue engineering a tendon-bone junction with biodegradable braided scaffolds"; Abstract: "The tendon-bone junction ... presents a significant clinical challenge. This study aimed to develop a biphasic scaffold for tendon-bone junction repair."; “The mechanical test results indicated that three different braided scaffold structures provided a wide range of mechanical properties that mimic the components of tendon bone junction…”). Ramakrishna teaches adjacent phases (first phase adjacent to second phase) as multiphase scaffold consisting of a tendon compartment and a bone compartment, wherein these compartments are inherently adjacent to form a continuous implant (Fig 1.).
Braided scaffolds inherently possess interconnected pores due to yarn crossings. Ramakrishna confirms porosity suitable for cell infiltration and tissue ingrowth, wherein macroporosity is demonstrated in Table 3 (see also Discussion and Conclusion related to porosity). The braided construct has exterior major surfaces (top, bottom, sides) that interface with host tissue (Figure 2). Braided scaffolds are designed with axial yarn orientation to bear tensile loads along the length (Mechanical properties section).
Ramakrishna explicitly identifies the clinical problem in that current strategies prioritize mechanical reattachment over regeneration of the native interface, resulting in poor outcomes (Background).This is the same problem the applicant seeks to solve. Ramakrishna is a single reference that teaches a braided, biphasic scaffold for tendon-bone junction repair that appears to be functionally equal to the applicant's biphasic osteotendinous repair scaffold. However, Ramakrishna does not teach electrochemically aligned collagen (ELAC), specific crosslinking agents (genipin/iridoids), or calcium phosphate mineralization.
Learn teaches mesenchymal stem cell (MSC)-seeded electrochemically aligned collagen (ELAC) threads woven into biotextile scaffolds as grafts to repair rotator cuff tendon defects at the tendon-bone junction [osteotendinous] in New Zealand White rabbits (Abstract), wherein individual threads [monofilaments] were combined [twisted] to form 3-ply yarns before crosslinking in genipin solution. Yarns were woven [braided on top of each other successively] around an array of seven pins [concentric] to a height of 5mm [requiring three or more layers to achieve] to form a scaffold unit [phase]. Two scaffold units [phases] were then stacked in parallel [adjacent and contiguous] and consolidated using a weft fiber passed through the pin-holes [directly attached] to produce a biotextile scaffold (page 4, Scaffold fabrication section, first paragraph). Figure 1 shows the interconnected macroporosities throughout the first and second phases [the two scaffold units], triaxial nature of the yarn (page 15, Figure 1A and 1B; showing X, Y and Z axis), oblique threads (page 15, Figure 1C) and wherein the majority of the ELAC threads are positioned along the load-bearing axis (page 15, Figures 1C and 1D). No other cells were described to be seeded at any concentration (page 5, Cell seeding of scaffolds section; rabbit MSCs sorted by flow in the pages 4-5, Flow sorting of rabbit MSCs were seeded), thus MSCs are more predominate than any other human or animal cells (i.e., being the only cells).
While the MSC used by Learn were allogenic, at the time of the invention, it was well-known in the field of regenerative medicine and orthopedic surgery that MSCs can be derived from two sources, allogeneic or autologous. The use of autologous MSCs was a well-established, conventional and preferred choice to avoid immune-associated complications or rejection. Therefore, given the option of two known, predictable cell sources for the same purpose, and where the choice of autologous MSCs is recognized as the highly preferable choice to avoid immune complications, it would have been obvious to a person of ordinary skill in the art to use autologous MSCs with the ELAC threads to obtain the predictable and beneficial result of improved biocompatibility and reduced immunogenicity in the scaffold. This represents an “obvious to try” situation where there are a finite number of identified, predictable solutions and one skilled in the art has a reason to pursue the known options (see KSR Int’l Co. v. Teleflex Inc., 500 U.S. 398 (2007)).
Learn teaches a generic 3-ply yarn and does not teach the specific claimed nuanced architecture choice of using 4-ply yarns for triaxial threads and 2-ply yarns for oblique threads. However, one of skill in the art would be motivated to make this modification as a matter of routine optimization to improve the mechanical properties of the scaffold taught by Learn by further tailoring the yarn properties to the specific mechanical function of each thread type within the braid. The triaxial threads run parallel to the load-bearing axis, are primarily responsible for carrying the tensile load, and require high strength and stiffness, thus it would be a matter of obvious routine experimental optimization to increase the 3-ply yarn to 4-ply for these threads to increase cross-sectional area to provide greater resistance to tensile failure under tension. Using a stronger yarn for the primary load-bearing threads is a logical choice. The oblique threads weave diagonally around the axial threads to constrain the axial threads, transfer load between axial threads and prevent them from splaying apart under tension, providing shear and torsional stability. A 2-ply yarn is more flexible and pliable than a 3-ply yarn, making it easier to weave tighter braid angles around the axial threads without creating excessive bulk or stress concentrations at the crossover points, which can improve overall structural integrity and fatigue resistance and the flexibility can allow for more control over the size and distribution of the pores between the axial threads. The combination of thicker axial threads and thinner braid threads allows for optimization of the microporosity of the scaffold as well by creating a pore size that is large enough for cell infiltration and tissue ingrowth (interconnected macroporosity) while maintaining a high density of collagen for mechanical strength. A uniform 3-ply yarn might force a compromise, resulting in either pores that are too small or a structure that is not as strong.
Learn teaches woven scaffolds with, “…demonstrated robust mechanical properties similar to that of native tendon, ample porosity for cellular infiltration and integration, along with biological cues to induce appropriate cellular responses (cell attachment and tissue integration, resorption, and remodeling)” (page 9, Discussion section, paragraph 2). Learn does not however teach the combination of a mineralized bone-phase with osteoinductive hydroxyapatite crystals or dicalcium phosphate dihydrate crystals distributed on the surface along with MSCs with his non-mineralized tendon-phase.
Thus, electrochemically aligned collagen (ELAC) threads, crosslinking in genipin solution, interconnected microporosity, mesenchymal stem cell seeding on ELAC scaffolds, scaffold for rotator cuff repair and tendon regeneration at tendon-bone junction are taught by Learn. Learn provides the missing ELAC thread technology that Ramakrishna does not teach. A person of ordinary skill in the art would substitute Ramakrishna's generic biodegradable fibers with Learn's ELAC threads because ELAC was shown to have superior tenogenic properties (Learn, Figs. 6-8).
Wang teaches, “… genipin crosslinking can help to maintain the stability of the soft materials to ensure sustained stimulation of MSCs and the release of beneficial growth factors. The inorganic elements in bioceramics (such as hydroxyapatite and β-tricalcium phosphate (β-TCP)) are similar to those in native bones, and they help to induce osteogenic differentiation. Genipin crosslinking, as an alternative to sintering, serves as an adhesive to bond bioceramic powder together. The physical properties and biocompatibility of materials consisting of bioceramics in genipin-crosslinked hydrogels have been assessed. Vozzi et al. constructed composite scaffolds involving collagen/gelatin/genipin/hydroxyapatite particles (HAps). HAps are highly stiff, and adding genipin led to a homogeneous mixture of stiff particles in soft materials. The addition of genipin increased the elastic modulus of the hydrogel, preventing HAp sedimentation…Other research focused on creating porous chitosan/nano β-TCP scaffolds… Another strategy for treating bone defects is to coat scaffolds with gels, such as genipin-crosslinked hydrogel (which can tightly adhere to the scaffold surface), leading to an increased stiffness and viscosity of coating gels to enhance biocompatibility… Additionally, MSCs in stiff genipin-treated hydrogel have been shown to exhibit tendencies toward mineralizing and differentiating, which was attributed to the mechanical signals from the stiff hydrogel stimulating MSCs toward osteogenic differentiation.” (pages 10-11, Bone regeneration section, paragraphs 1-3).
The combination of his reviewed teachings renders it obvious to try a mineralized bone scaffold comprising ELAC bonded with hydroxyapatite by genipin crosslinking, further coated with MSCs. Wang provides the missing mineralization and crosslinking teachings that Ramakrishna and Learn do not address.
Learn provides motivation to combine a mineralized bone-phase with MSCs with the non-mineralized tendon-phase given his results wherein scaffold-alone repairs displayed a mixed mode failure at the interface between the soft tissue and bone and at the midsubstance and the cell-seeded scaffold repairs failed consistently within the midsubstance (page 8, Biomechanical testing section, paragraph 2; page 18, Figure 4). In addition, regeneration of bone–tendon interfaces are a well-known clinical challenge. Thus, Learn in combination with the teachings of Wang provides obviousness to adopt a biphasic scaffold for osteotendinous repair wherein braided ELAC threads form distinct mineralized phase for bone integration and a non-mineralized phase for tendon integration that are braided together as in the two separate scaffold units of Learn to create a strong, porous, three-dimensional scaffold, thereby arriving at the claimed invention with a reasonable expectation of success.
Learn also further provide rationale for only seeding MSCs on the first mineralized bone-phase in his discussion by stating, “Biomechanical testing data suggest that addition of MSCs to woven collagen scaffolds may enhance repair stiffness and strength. Furthermore, MSC supplementation likely enhanced the integration between the bone and the scaffold as reflected by consistent failure occurring at the midsubstance region. This is potentially the result of cell-mediated integration between soft (tendon) and hard (bone) tissues.” (page 9, Discussion section, paragraph 3). In addition, “ELAC fibers within the group containing the scaffold alone (no MSCs) appear to be sufficient to induce tenogenic differentiation of the cells that infiltrate and encapsulate the scaffold, as no significant differences in presence of tenomodulin were noted between scaffold-alone and cell-seeded groups.” (page 10, Discussion section, paragraph 7). Thus, since the MSCs enhanced stiffness and strength, however did not offer any advantage in inducing tendon cells, it would be logical to only include seeding MSCs in the first mineralized bone-phase to reinforce stiffness and strength of bone as compared to tendon and remove their inclusion from the tendon phase as they do not appear to confer an advantage.
Wan teaches biphasic scaffold architecture of adjacent braided collagen phases (claims 1, 3 and 4) with triaxial fibers (¶[0007], ¶[0014], Fig. 6), wherein "at least one tri-axe fiber 34 ... routed straight within the braid pattern along the longitudinal axis (A) of the construct” (¶[0093]) and the collagen may be crosslinked (¶[0081]; NDGA-polymerized collagen fibers in ¶[0075]). Wan also teaches bundles of parallel fibers forming yarns (claim 3). Wan provides the missing triaxial braiding teaching. Wan's "tri-axe fiber" is structurally identical to the claimed triaxial ELAC threads, a fiber running straight along the longitudinal axis within a braided structure. Ahn strengths this by also teaching that three-dimensional braid architectures, triaxial braid textile constructs, and interconnected macroporous scaffold geometries are known tissue-engineering scaffold design choices (Abstract). Learn teaches aligned collagen thread-based tendon scaffold structure and Wan, further supported by Ahn, teaches that triaxial braided architecture is a known textile scaffold geometry that improves mechanical anisotropy, pore interconnectivity, and load-bearing behavior desirable for tendon-bone repair.
It would have been prima facie obvious to one of ordinary skill in the art prior to the instant effective filing date to combine the teachings of Ramakrishna and Learn’s biphasic braided scaffold with ELAC threads because Ramakrishna teaches a biphasic braided scaffold for tendon-bone junction but uses generic biodegradable fibers. Learn teaches that ELAC threads have superior tenogenic properties for tendon repair. A person of ordinary skill in the art would have been motivated to substitute ELAC threads to improve tenogenic differentiation, a predictable result.
A person of ordinary skill in the art would have been motivated to combine the teachings of Ramakrishna with the mineralization of bone phase by Wang because the references address the same problem. Wang teaches genipin crosslinking and hydroxyapatite mineralization of collagen scaffolds. A person of ordinary skill in the art would apply Wang's mineralization to the bone-phase of Ramakrishna's biphasic scaffold to promote osteointegration, as Ramakrishna explicitly identifies the need for improved bone integration.
A person of ordinary skill in the art would have been motivated to combine the teachings of Ramakrishna with the triaxial braiding of Wan because Wan teaches that triaxial fibers within a braid provide additional mechanical support along the load-bearing axis. A person of ordinary skill in the art would incorporate triaxial fibers into Ramakrishna's biphasic braided scaffold to improve tensile strength and reduce stretching under load, a predictable mechanical improvement.
A person of ordinary skill in the art would have been motivated to combine the teachings of Learn with the crosslinking of Wang as a predictable alternative. Learn uses genipin crosslinking for ELAC threads. Wang teaches genipin as a superior biocompatible crosslinker for collagen with mineral phases. A person of ordinary skill would use genipin crosslinking throughout both phases for consistent biostability.
A person of ordinary skill in the art would have had a reasonable expectation of success in combining the teachings of Ramakrishna, Learn, Wang, and Wan because Ramakrishna already demonstrates a working biphasic braided scaffold for tendon-bone junction repair. Substituting ELAC threads (Learn) is a direct replacement of one collagen fiber with another collagen fiber having known mechanical properties. Mineralization of collagen scaffolds was routine by 2020 (Wang), with established methods for hydroxyapatite deposition on porous collagen. Ramakrishna's braided scaffold, with its inherent macroporosity, is a suitable substrate for Wang's mineralization technique.
Triaxial/tri-axe fibers were already demonstrated in collagen braids (Wan, ¶[0093]). Incorporating them into Ramakrishna's braid pattern is a minor modification expected to improve axial stiffness, a predictable result. Genipin crosslinking was already used for ELAC threads (Learn) and for mineralized collagen composites (Wang). Using the same crosslinker for both phases ensures uniform biostability. In re O’Farrell, 853 F.2d 894 (Fed. Cir. 1988) shows that there is a reasonable expectation of success exists when prior art provides reasonable direction and the result is predictable.
Regarding dependent claim 2, Learn teaches twisting ELAC threads to form yarns as discussed above. A person of ordinary skill in the art would apply this same yarn formation to both phases of the Ramakrishna scaffold. Regarding dependent claim 3, 4-ply and 2-ply yarns are not explicitly taught, however selecting different ply counts for different functional roles (axial vs. oblique) as use of 4-ply yarns as triaxial threads and 2-ply yarns as oblique threads is routine optimization of thread architecture. The selection reflects predictable balancing of axial tensile strength, braid flexibility, pore geometry, fatigue resistance. No criticality or unexpected results have been shown. It would be obvious to one of skill in the art thar more plies are stronger but stiffer and fewer plies are more flexible (see also evidentiary reference US-20080188933-A1). A person of skill in the art would use 4-ply for load-bearing triaxial threads and 2-ply for oblique threads as a matter of routine design.
Regarding dependent claim 4, Wan teaches three concentric layers braided successively (first layer at 5 PPI, second at 15 PPI, third at 20 PPI; ¶[0015]); see also evidentiary reference US-20080188933-A1 which teaches multi-layer braided constructs in Figs. 4A-4C. Three or more concentric braided layers represent an obvious scaling/design parameter to obtain desired scaffold thickness, porosity, and mechanical strength. It would be obvious to one of skill in the art to apply this to both phases.
Regarding dependent claim 5, Learn teaches individual ELAC threads. Braiding monofilaments, rather than twisted yarns, is an obvious and simple known alternative. Regarding dependent claim 6, positioning a majority of threads along the load-bearing axis is inherent to triaxial braided axial-thread scaffold design. Wan teaches tri-axe fibers running straight along the longitudinal axis (load-bearing axis). Ramakrishna's biphasic scaffold inherently has axial threads for tensile strength.
Regarding dependent claims 7-9, Wang teaches the use of iridoid crosslinking agents, including genipin. Other iridoids (loganin aglycone, oleuropein aglycone) are known natural crosslinkers, substituting one for another is obvious as they are predictable alternatives. Regarding dependent claim 10, Wang teaches hydroxyapatite and suggests dicalcium phosphate, which is a known alternative calcium phosphate mineral for bone regeneration that is obvious. Regarding dependent claims 11-12, Ramakrishna's biphasic scaffold has compartments that are contiguous. Learn teaches stacking and contiguous or directly attached adjacent scaffold units.
Regarding dependent claims 13-15, Learn teaches mesenchymal stem cells seeding on ELAC scaffolds, as discussed above. Ramakrishna identifies the need for cells to promote regeneration. Selective seeding on mineralized bone-phase only is obvious because mesenchymal stem cells promote osteogenesis on mineralized scaffolds. Learn admits mesenchymal stem cells did not enhance tenogenic differentiation in the tendon phase, so a person of ordinary skill in the art would omit them from the tendon phase (see In re Applied Materials, 692 F.3d 1289 (Fed. Cir. 2012), wherein optimizing feature placement based on known properties is obvious).
Regarding dependent claim 16, in a biphasic scaffold with adjacent phases, the major surfaces of each phase inherently form one side of the overall scaffold. This is an obvious geometric consequence of two adjacent scaffold phases arranged side-by-side to define an external scaffold surface. No additional structural distinction is added in instant claim 16 over the combined prior art.
Response to Arguments
The applicant’s Arguments/Remarks of the reply, filed 30 March 2026, have been fully considered. The applicant argues that the combination of Learn and Wang fails to teach or suggest a biphasic scaffold with braided, as opposed to woven, triaxial ELAC threads and that the distinction between weaving and braiding is patentably significant. The applicant further argues that Learn does not teach selective mineralization of only one phase. These arguments are not persuasive.
The applicant argues that Learn’s scaffold is woven not braided, and that the examiner improperly blurred the distinction between those textile processes. The argument is recognized, the examiner acknowledges the general differences between weaving and braiding and agrees that portions of the prior Office Correspondence used the terminology woven and braided imprecisely. To that extent, the prior characterization is withdrawn. However, withdrawal of that terminology does not compel allowance. The dispositive inquiry under 35 U.S.C. § 103 is not whether Learn uses applicant’s exact nomenclature, but whether the claimed structural arrangement as a whole would have been obvious to a person of ordinary skill in the art (see KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398 (2007)).
Learn teaches electrochemically aligned collagen (ELAC) threads, load-bearing collagen biotextile scaffold architecture, multi-layer yarn organization, interconnected macroporosity suitable for tissue infiltration, osteotendinous repair use. Learn therefore provides the foundational collagen scaffold platform and expressly recognizes the mechanical design considerations relevant to tendon-bone repair.
The applicant correctly notes that Learn does not expressly disclose a triaxial braided architecture having axial threads extending substantially along the scaffold axis. However, for the purposes of the claimed scaffold structure, specifically, the features of triaxial thread orientation, concentric layering, interconnected macroporosity, and load-bearing axis, the woven scaffold of Learn achieves the same functional result as the claimed braided scaffold. The mere label of the textile process does not render the claim nonobvious where the resulting structural and functional features are substantially similar.
In addition, the applicant’s own specification does not elevate braiding to a critical, unobvious distinction. In ¶[0065] the specification merely states that braiding can better position threads along the load-bearing axis, not that weaving cannot. Learn, however, already achieves a majority of ELAC threads along the load-bearing axis (see Learn Fig. 1C, 1D, showing X-axis alignment). Thus, the asserted advantage of braiding over weaving is already present in the prior art woven scaffold.
Further, any distinction represents a known textile architecture substitution for predictable mechanical performance enhancement, not a teaching away. One of ordinary skill would recognize that substituting a known braiding technique for a known weaving technique to produce a similar triaxial, load-aligned fibrous scaffold is a matter of routine engineering choice, not inventive step. The claimed advantage identified by the applicant, namely improved alignment of load-bearing fibers along the principal loading axis, is itself the very reason such substitution would have been obvious.
A person of ordinary skill in the scaffold engineering and biomedical textile arts would have understood that axial/triaxial braided structures were conventionally used where increased longitudinal tensile load transfer, reduced axial extension, and improved structural integrity under cyclic loading were desired. In tendon and osteotendinous applications, where load is predominantly longitudinal, substituting a braided triaxial architecture for Learn’s woven collagen architecture would have been an obvious design choice motivated by predictable mechanical benefits. Accordingly, the applicant’s argument is not persuasive.
The applicant argues Learn does not teach triaxial threads because the yarns are wound over and under pins in a sinusoidal pattern, and under tensile load along X, the scaffold will stretch. The examiner agrees that Learn does not expressly use the term “triaxial”. However, obviousness does not require an express textual disclosure of identical terminology. The relevant question is whether it would have been obvious to employ axial threads extending substantially along the scaffold length, together with oblique interlaced threads in order to optimize mechanical performance of a collagen scaffold intended for load-bearing osteotendinous repair. The record supports such conclusion.
Learn, Figures 1A and 1B, explicitly labels the X, Y, and Z axes and describes the yarn orientation as providing reinforcement that is triaxial, without directly using the term “triaxial”. The fact that the threads follow a sinusoidal path does not negate their triaxial orientation, as many triaxial braids also have undulating thread paths. Moreover, the claimed invention does not require that triaxial threads be perfectly straight or non-sinusoidal. Thus, Learn teaches the identical triaxial thread concept recited in the claim. Further, Learn repeatedly emphasizes tensile function, scaffold anisotropy, load-bearing repair, mechanically functional collagen architecture. The use of axial load-carrying threads with surrounding oblique braid threads is a well-understood and predictable mechanical adaptation in textile engineering. The applicant has not identified any criticality in the claimed triaxial architecture beyond predictable mechanical consequences. Accordingly, the argument is not persuasive.
The applicant argues Learn’s two scaffold units are stacked in parallel and therefore cannot yield the claimed arrangement in which only the first phase contains calcium phosphate mineral while the second phase remains non-mineralized. This argument is not persuasive.
Claim 1 requires a first phase comprising ELAC threads and calcium phosphate mineral, a second phase comprising ELAC threads, and the second phase adjacent to the first phase. Claim 1 does not require complete encapsulation, internal nesting, exclusion of all exposed surfaces, a specific interfacial geometry other than adjacency. Learn teaches physically adjoining collagen scaffold regions and provides two discrete scaffold units stacked and attached adjacently (Fig. 2B). Wang teaches mineralization of collagen scaffolds with calcium phosphate materials including hydroxyapatite. A skilled artisan would understand that mineralizing only one of the two discrete scaffold units prior to stacking/attachment directly yields a biphasic scaffold with a mineralized first phase and non-mineralized second phase. There is no structural or procedural barrier to this combination. The prior art is not required to explicitly teach every minute manufacturing step for obviousness.
The applicant argues that Wang does not disclose braided triaxial collagen phases or biphasic adjacent phases. That argument is not persuasive because the rejection does not rely on Wang for the entirety of the scaffold architecture. Rather, Learn provides the collagen scaffold structural platform and osteotendinous repair motivation. Wang provides teachings of genipin crosslinking and calcium phosphate mineralization for osteogenic collagen constructs. A reference need not teach all claim limitations individually (see In re Merck & Co., 800 F.2d 1091 (Fed. Cir. 1986)).
A person of ordinary skill would have found it obvious to selectively mineralize one scaffold region while leaving the adjacent collagen region non-mineralized to emulate the known biphasic bone-tendon interface. Selective regional mineralization of one collagen phase while leaving another unmineralized represents no more than routine spatial control of a known scaffold treatment. The fact that Learn’s original scaffold units were not expressly described as selectively mineralized does not negate obviousness of such modification. Accordingly, the argument is not persuasive.
The applicant argues Learn cannot teach the specific 4-ply (triaxial) and 2-ply (oblique) yarn architecture of claim 3. However, the prior Office Correspondence explained that optimizing ply number based on mechanical function (axial load-bearing vs. oblique constraint) is routine optimization. Increasing ply for axial threads to improve tensile strength and decreasing ply for oblique threads to improve flexibility and reduce bulk are predictable, logical design choices. This is an “obvious to try” situation with a finite number of identified solutions.
In summary, the applicant’s arguments regarding the distinction between weaving and braiding are unpersuasive because Learn already achieves the claimed structural and functional features. The combination of Learn and Wang renders claims 1-15 obvious, however the examiner’s original rejection were set aside, based on the amendment to claim 1, to provide a rejection including newly cited additional prior art to more explicitly support the braiding teachings, that, combined with Learn and Wang, render all claims obvious.
Conclusion
No claims are allowed.
The applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (87 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to REBECCA L. SCOTLAND whose telephone number is (571) 272-2979. The examiner can normally be reached M-F 9:00 am to 5:00 pm EST.
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:/Awww.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’ s supervisor, Robert A. Wax can be reached at (571) 272-0623. 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:/Awww.uspto.gov/patents/apply/patent- center for more information about Patent Center and https:/Awww.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.
/RL Scotland/
Examiner, Art Unit 1615
/Robert A Wax/Supervisory Patent Examiner, Art Unit 1615
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