DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application is being examined under the pre-AIA first to invent provisions.
Response to Arguments
Applicant's arguments filed 01/28/26 have been fully considered but they are not persuasive.
On page 8-10 regarding prior art rejections, Applicant argues substituting ePTFE for rotational spun PTFE is not a simple substitution as the Examiner asserts in the office action. Applicant discusses how a human body can respond differently to different materials, referring to an affidavit filed 2017 for a different case, supports this statement, and again presents arguments regarding the invention’s status in front of the FDA. These arguments are the same as those presented on pages 12/13 on the Applicant’s response mailed 05/16/25.
The Examiner respectfully disagrees for the same reasons enumerated on pages 4-5 of the non-final rejection mailed 08/28/25 in response to the same arguments. Namely, the Examiner agrees that the human body reacts differently to different materials. This is something a person of ordinary skill understands however, and points out the two materials are well-known for not causing immune responses to a human body. The Examiner maintains that a person of ordinary skill would have motivation to try the switch from one biocompatible polymeric material to another biocompatible polymeric material, and maintains that any person of ordinary skill within the implant arts would have guidance and understanding of how the change in material would act within the human body. The Examiner also again reminds Applicant that processes or procedures of the FDA are not related to device patentability.
On page 11 Applicant argues the prior art does not discuss a finite number of predictable solutions, and instead concludes the list is “infinite”. This argument is also similar to previously filed arguments from 05/16/25.
The Examiner respectfully disagrees and maintains the combination of references is obvious, maintaining the remarks mailed 08/28/25.
On page 13 Applicant argues amendments to claims 39 and 48 are made to render the dependent claims allowable.
The Examiner respectfully refers to the rejection below regarding amended subject matter.
Claim Rejections - 35 USC § 103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claim(s) 31-39, 41-48, 50 is/are rejected under pre-AIA 35 U.S.C. 103(a) as being unpatentable over Anneaux et al. (US 20130325109 A1) hereinafter known as Anneaux in view of Lozano et al. (US 20090280325 A1) hereinafter known as Lozano, and further in view of Helmus et al. (US 20080208325 A1) hereinafter known as Helmus.
Regarding claim 41, Anneaux discloses a medical appliance comprising:
a first layer (Figure 4, one of items 1) of PTFE ([0025] expanded PTFE) disposed on an inside surface of the appliance ([0015] tubular device; Figure 4 shows one of layers 1 being on an inside surface);
a tie layer coupled to the first layer (Figure 4 item 2), and
a second layer of PTFE (Figure 4, one of items 1),
wherein the tie layer is disposed between the first and second layers (Figure 4),
but is silent with regards to the first layer being rotational spun, and is silent with regards to whether the tie layer is impervious to cell migration.
However, regarding claim 41 Lozano teaches that polymer fibers ([0025]) of medical devices ([0005], [0097]) can be rotationally spun ([0016], [0028], [0013], [0008] (see also Anneaux [0015] which teaches that PTFE polymer can be formed into solution and so spun)). Anneaux and Lozano are involved in the same field of endeavor, namely spun polymers for medical devices. It would have been obvious to one of ordinary skill in the art at the time the invention was filed to modify the medical appliance of Anneaux by adjusting the manufacturing method of the PTFE layer of Anneaux be rotationally spun instead of expanded, since the courts have held that the simple substitution of one known element for another to obtain predictable results in a prima facie case of obviousness. See MPEP 2143 (I)(B), and since the courts have held that choosing from a finite number of identified, predictable solutions with a reasonable expectation of success results in a prima facie case of obviousness. See MPEP 2143 (I)(E). In this case, Anneaux teaches a medical appliance with an expanded PTFE layer (Figure 4 item 1; [0025]), and teaches that expanded PTFE layers have a microstructure which can be adjusted in order to encourage or inhibit cell ingrowth ([0032]). Anneaux also teaches PTFE can be made into solution which has the potential to be spun in order to form sub-micron fibrous mats for implants ([0015]-[0016]), and Lozano teaches how medical appliances ([0005], [0097]) made of sub-micron polymer fibers can be manufactured via rotational spinning ([0016], [0028], [0013], [0008]) in order to provide scaffolding for tissue ingrowth ([0005]). Thus, the substitution of an expanded PTFE layer for a PTFE layer made by rotational spinning would have been an obvious substitution and obvious to try, and would have been considered one identified solution to how to manufacture a PTFE layer of a stent graft.
Further, regarding claim 41 while Anneaux teaches the properties of each of the layers of the medical appliance can be adjusted and optimized based on the desired amount of ingrowth allowed ([0032]) and teaches the ranges of node/fibril distances within their materials to prevent ingrowth ([0033]), they are silent with regards to whether the tie layer should be impervious to ingrowth. Helmus however, teaches a spun polymer medical appliance (Figure 2) which includes a barrier layer which is impervious to cell growth (Figure 2 item 120, [0106], [0026]). Anneaux and Helmus are involved in the same field of endeavor, namely medical appliances. It would have been obvious to one of ordinary skill in the art at the time the invention was filed to modify the appliance of the Anneaux Lozano Combination so that the tie layer is impervious to cell migration therein as is taught by Helmus in order to optimize ingrowth into only the external or internal layers of the stent, and preventing over-proliferation of cells after installation into a patient, which would potentially result in restenosis.
Regarding claims 32 and 42, the Anneaux Lozano Helmus Combination teaches the medical appliance of claim 41 substantially as is claimed,
wherein Anneaux further discloses the second layer is porous ([0032]).
Regarding claims 33 and 43, the Anneaux Lozano Helmus Combination teaches the medical appliance of claim 41 substantially as is claimed,
wherein Anneaux further discloses the second layer comprises ePTFE ([0025]).
Regarding claims 35 and 44, the Anneaux Lozano Helmus Combination teaches the medical appliance of claim 41 substantially as is claimed,
wherein Anneaux further discloses the tie layer comprises FEP ([0015]).
Regarding claims 38 and 47, the Anneaux Lozano Helmus Combination teaches the medical appliance of claim 44 substantially as is claimed,
wherein Anneaux further discloses the tie layer is a sheet ([0021]) of FEP disposed around the first layer (Figure 4).
Regarding claims 39 and 48, the Anneaux Lozano Helmus Combination teaches the medical appliance of claim 31/41 substantially as is claimed,
wherein Anneaux further discloses the tie layer is bonded to the first and second layers ([0035], [0050]-[0051]) by heating the tie layer ([0054]), so the tie layer is melted so that it partially flows into openings in the first and second layers (Anneaux discloses the first and second layers have openings ([0002] well-defined porous microstructure, [0004], [0017], [0028], etc.), and discloses the tie layer is FEP ([0015]) and can be heated from 35-485°C to bond the tie layer to the first and second layers ([0054]); Applicant’s specification indicates FEP becomes soft (melts) and flows into open spaces in adjacent layers by heating to 325°C ([0135]). Since Anneaux discloses heating anywhere from 35-485°C, Anneaux inherently discloses the FEP layer melt bonds by partially flowing into openings in the layers as the claim requires, since it is made of the same materials and melted to the same temperature.).
Regarding claim 50, the Anneaux Lozano Helmus Combination teaches the medical appliance of claim 41 substantially as is claimed,
wherein Anneaux further discloses the appliance is tubular ([0015]).
Regarding claim 31, the Anneaux Lozano Combination teaches the medical appliance of claim 41 substantially as is claimed,
wherein Anneaux further discloses a stent with a frame (Figure 4 item 3; [0023]) configured to resist radial compression when disposed in a lumen of a patient (The applicant is advised that, while the features of an apparatus may be recited either structurally or functionally, claims directed to an apparatus must be distinguished from the prior art in terms of structure rather than function. In addition, it has been held by the courts that apparatus claims cover what a device is, not what a device does. See MPEP 2144 (I). In this case, the patented apparatus of Anneaux discloses (as detailed above) all the structural limitations required to perform the recited functional language, therefore was considered to anticipate the claimed apparatus. See, for example 0005]), and the medical appliance is a covering coupled to the framing (Figure 4).
Regarding claim 34, the Anneaux Lozano Helmus Combination teaches discloses the stent of claim 31 substantially as is claimed,
wherein Anneaux further discloses the frame is disposed between the first and second layers (Figure 4).
Claim(s) 31, 40-41 and 49 is/are rejected under pre-AIA 35 U.S.C. 103(a) as being unpatentable over House et al. (US 5620763 A) hereinafter known as House in view of Lozano (and evidenced by Anneaux) as is applied above, further in view of Chu (US 20080188923 A1).
Regarding claim 41, House discloses a medical appliance (Column 1 lines 47-50) comprising:
a first layer of PTFE disposed on an inside surface of the appliance, a tie layer coupled to the first layer which is impervious to cell migration therethrough, and a second layer of PTFE, wherein the tie layer is disposed between the first and second layers (Column 5 lines 16-27; two layers of porous expanded PTFE which sandwich a non-porous layer of FEP; Column 34-35 the sandwich of layers is formed into a tube with one ePTFE layer on an inside surface),
but is silent with regards to the first layer of PTFE being rotationally spun.
However, regarding claim 41 Lozano teaches that polymer fibers ([0025]) of medical devices ([0005], [0097]) can be rotationally spun ([0016], [0028], [0013], [0008]). House and Lozano are involved in the same field of endeavor, namely spun polymers for medical devices. It would have been obvious to one of ordinary skill in the art at the time the invention was filed to modify the medical appliance of House by adjusting the manufacturing method of the PTFE layer of House be rotationally spun instead of expanded, since the courts have held that the simple substitution of one known element for another to obtain predictable results in a prima facie case of obviousness. See MPEP 2143 (I)(B), and since the courts have held that choosing from a finite number of identified, predictable solutions with a reasonable expectation of success results in a prima facie case of obviousness. See MPEP 2143 (I)(E). In this case, House teaches a medical appliance with a micro-fiber expanded PTFE layer (Column 5 lines 16-17), with fibers defining pores (Column 1 lines 9-10); and Anneaux teaches that expanded PTFE layers have a microstructure which can be adjusted in order to encourage or inhibit cell ingrowth ([0032]) and also teaches that PTFE can be made into solution which has the potential to be spun in order to form sub-micron fibrous mats for implants ([0015]-[0016]); Lozano teaches how medical appliances ([0005], [0097]) made of sub-micron polymer fibers can be manufactured via rotational spinning ([0016], [0028], [0013], [0008]) in order to provide scaffolding with openings for tissue ingrowth ([0005]). Thus, the substitution of an expanded PTFE layer for a PTFE layer made by rotational spinning would have been an obvious substitution and obvious to try, and would have been considered one identified solution to how to manufacture a PTFE layer of a stent graft.
Regarding claim 49, the House Lozano Combination teaches the medical appliance of claim 41 substantially as is claimed,
but is silent with regards to whether the tie layer is non-fibrous or not.
However, regarding claim 49 Chu teaches impermeable FEP barrier layers in medical appliances can be non-fibrous ([0071] FEP films or sheets which are molded). House and Chu are involved in the same field of endeavor, namely medical appliances. It would have been obvious to one of ordinary skill in the art at the time the invention was filed to modify the appliance of the House Lozano Combination so that the tie layer is non-fibrous as is taught by Chu as a known alternative configuration to a porous layer. The Examiner notes that as long as the function of the FEP layer (of being non-porous) is maintained, a specific non-fibrous configuration is obvious to one of ordinary skill.
Regarding claims 31 and 40, the House Lozano Combination teaches the medical appliance of claim 41 substantially as is claimed,
wherein House further discloses a stent with a frame (Column 1 lines 46-49; a stent is understood to inherently have some frame, or it would be unable to achieve their intended purpose), wherein the medical appliance is a covering coupled to the framing (Column 1 lines 46-48 coverings for intraluminal stents). While not expressly discussed, it is considered obvious to a person of ordinary skill in the art that an intraluminal stent would be capable of resisting radial compression when disposed in a lumen of a patient, as this is the general understanding of the function of stents in the art. See, as evidence, Anneaux (Figure 4 item 3; [0023], [0005]).
Conclusion
THIS ACTION IS MADE FINAL. 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 extension fee 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 Jacqueline Woznicki whose telephone number is (571)270-5603. The examiner can normally be reached M-Th 10am-6pm EST.
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/Jacqueline Woznicki/Primary Examiner, Art Unit 3774 02/04/26