DETAILED ACTION
The receipt is acknowledged of applicants’ amendment and request for continued examination (RCE) filed 04/24/2026; and IDS filed 04/28/2026.
Claims 13-25 are pending.
Claims 19-23 are withdrawn from further consideration pursuant to 37 CFR 1.142(b), as being drawn to a nonelected inventions, there being no allowable generic or linking claim. Applicant timely traversed the restriction (election) requirement in the reply filed on 09/14/2020.
Claims 13-18 and 24-25 are subject of this office 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 .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 04/24/2026 has been entered.
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 the applicant regards as his invention.
Claims 17 and 24 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 (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Regarding claim 17, the claims are rendered indefinite by raising a question or doubt introduced by the limitations following the expression “preferably” because it is subject of more than one interpretation, and one interpretation would render the claim unpatentable over the prior art. The term “preferably” implies choices amongst a number of different alternatives. The instant disclosure does not provide sufficient definition or context for the term “preferably” to know definitively under what circumstances that the ‘preferred’ embodiment of removing the solvent from the drug-containing polymer solution as recited in claim 17 (i.e., by freeze-drying), is necessarily required in order for one to meet the limitations of the claim. As such, one of skill in the art would not be able to determine the metes and bounds of what is necessarily encompassed by the claim language and what is necessarily excluded by the claim language.
Notably, in the last step of claim 17, which is directed to substantially removing the solvent from the drug-containing solution, there is a recitation that this step is done “preferably by freeze-drying”. This is a clear example of exemplary language, where a generic limitation (i.e., “removing the solvent”) is followed by an exemplary term (e.g., “preferably”, “e.g.”, “such as”, etc.), which is then followed by one or more specific embodiments of the generic limitation. As shown in MPEP 2173.05(c), this can make the metes and bounds of what’s required by a claim vague and indefinite in that it’s not necessarily clear whether or not the narrower embodiment(s) is/are required for the claimed invention. For example, in the instant case, the exemplary term used is “preferably”. This term implies that the narrower embodiment is a preferred embodiment, at least some of the time. In the instant case, the term “preferably” is not defined in the instant specification in any limiting way regarding the context in which it is used in claim 17 (i.e., regarding the substantial removal of the solvent from the drug-containing polymer solution). For example, a review of the original disclosure reveals that there does not appear to be a general definition of the term “preferably” in the disclosure. In addition, the only instance in which the term “preferably” is used in the instant disclosure in the same context as is recited in claim 17 is at page 4, line 2. Notably, this instance does not clearly indicate under what circumstances that freeze-drying is the ‘preferred’ or required approach to substantially removing the solvent from the drug-containing polymer solution. Moreover, this section of the disclosure doesn’t indicate what other choices are available to one of skill in the art for removal of the solvent from the drug-containing polymer solution. Indeed, a review of the original disclosure indicates that no other alternative approach is described for this step of removing the solvent from the drug-containing polymer solution. For example, the only approach shown in the working examples is an overnight freeze-drying step that results in the desired drug-containing foam layers (e.g., see pages 12-14; Formulations 1-3; etc.). This strongly implies that freeze-drying might be required by the method of claim 17 when the claim is read in light of the original disclosure.
On the other hand, the term “preferably” implies alternative choices and that the ‘preferred’ embodiment is merely preferred some of the time. For example, the Merriam-Webster online dictionary defines the term “preferably” as “by choice or preference --> used to indicate what is wanted or preferred” (https://www.merriam-webster.com/dictionary/preferably). Thus, the use of “preferably” in claim 17 indicates that at least some of the time one can use alternative approaches to removing the solvent from the drug-containing polymer solution (e.g., air drying without freezing, etc.). Therefore, it is not necessarily clear whether the step of freeze-drying the drug-containing polymer solution is required by the product-by-process limitation as recited in claim 17. If it is not necessarily required, it is also not clear as to under what circumstances that the step of freeze-drying is ‘preferred’ or required because the instant disclosure does not describe those fact patterns. For these reasons, one of skill in the art would not be able to determine what embodiments are necessarily encompassed by claim 17 and which embodiments are necessarily excluded by the language of claim 17.
Regarding claim 24, the claim is vague and indefinite due to the use of the exemplary language “such as” following a generic limitation and before a list of specific embodiments of the generic limitation. This issue is compounded by the use of the relative language “and the like” as part of the Markush group of more specific embodiments of the generic limitation that is recited after the term “such as”. The instant disclosure does not clearly define the “bodily structures” as recited in claim 24 in a limiting way and does not clearly define what is meant by the term “and the like”. In addition, claim 24 merely recites the same language that is used in the spec for the ‘bodily structures’ limitation such that it is not clear that the specific embodiments that follow the term “such as” are necessarily limiting for claim 24 (e.g., see page 1, third paragraph; page 11, third paragraph; etc.). Thus, one of skill in the art would not necessarily recognize, when the claim is read in view of the disclosure, whether the structures that follow after the term “such as” are necessarily required by the claim. In addition, when read in view of the original disclosure, it is not clear what is intended by Applicant with the recitation of the term “and the like” such that it is not clear what bodily structures are necessarily included by the term and which bodily structures are excluded by the term. For each of these reasons, one of skill in the art would not be able to determine the metes and bounds of what is encompassed by claim 24, and what is not encompassed by claim 24, when the claim is read in view of the original disclosure.
There are two main issues that cause the metes and bounds of claim 24 to be vague and indefinite: (i) the use of exemplary language (i.e., “such as”) following a generic limitation (i.e., “bodily structures”) and followed by narrower species of that generic limitation (e.g., veins, arteries, etc.), and (ii) the use of the relative term “and the like” as a narrower, undefined embodiment of the generic term.
Regarding point (i), MPEP 2173.05(c) makes clear that exemplary language can make the metes and bounds of a claim indefinite. In the instant case, claim 24 merely recites the same language that is used in the spec for the ‘bodily structures’ limitation such that it is not clear that the specific embodiments that follow the term “such as” are necessarily limiting for claim 24 (e.g., see page 1, third paragraph; page 11, third paragraph; etc.). For example, no other specific examples of bodily structures that might be encompassed by the language of claim 24 appear to be provided by the instant disclosure, implying that the examples following the words “such as” in the claim are actually limiting for claim 24. For example, the second paragraph at page 11 indicates that the claimed foam can be used to deliver drugs to tissues and/or cavities. On the other hand, the disclosure appears to be silent regarding which types of tissues or cavities, both of which could be considered as “bodily structures”, are encompassed by the multilayered drug eluting foam of claim 24 and which types of tissues and cavities are not encompassed by the language of claim 24. Thus, one of skill in the art would not necessarily recognize, when the claim is read in view of the disclosure, whether the structures that follow after the term “such as” are necessarily required by the claim.
Regarding point (ii), the instant disclosure does not appear to define the term “and the like” in the context of bodily structures that are encompassed by the claim. Nor does the specification make clear what types of bodily structures are excluded by the relative term “and the like” (e.g., how similar to the recited embodiments does a body tissue or cavity have to be in order to read on the claim?). As pointed out above, the second paragraph at page 11 indicates that the claimed foam can be used to deliver drugs to tissues and/or cavities. Yet, the disclosure appears to be silent regarding which types of tissues or cavities, both of which could be considered as “bodily structures”, are encompassed by the multilayered drug eluting foam of claim 24, and which types of tissues and cavities are not encompassed by the language of claim 24. Thus, when claim 24 is read in view of the original disclosure, it is not clear what bodily structures (e.g., tissues and/or cavities) are necessarily encompassed by the recitation of “and the like” and which structures are excluded by this relative terminology.
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 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 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(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 13-18 and 24 are rejected under 35 U.S.C. 103 as being unpatentable over Patel et al. (WO 2010/025219, of record) in view of Hissink et al. (WO 2004/062704, of record), or alternatively, Hissink in view of Patel, and each combination further optionally combined with CA 2682291 (hereinafter CA ‘291, of record), and optionally combined with Pauletti et al. (WO 2004/041118, of record), and further combined with Chandrashekhar et al. (WO 2014/035245, IDS filed 04/28/2026).
Applicant Claims
Claim 13 is directed to multilayered drug eluting biodegradable foam comprising at least two foam layers, wherein the at least two foam layers are directly stacked on top of each other, wherein the at least two foam layers have a porosity of 85-99%, wherein each layer before degradation of the polymer independently comprises voids and a wall that comprises a polymer and wherein at least one of said layers is a drug-comprising layer, which comprises at least one drug that is mixed with the polymer in said drug-comprising layer, wherein the at least one drug is located in the wall of the foam of the drug-comprising layer and not in the voids before degradation of the polymer such that the drug elutes upon degradation of the polymer, wherein each of the at least two foam layers individually comprises a polymer that is a phase-separated polymer comprising at least one amorphous segment and at least one crystalline segment, wherein said amorphous segment optionally comprises a hydrophilic segment.
Determination of the Scope and Content of the Prior Art
(MPEP §2141.01)
Patel teaches wound dressing comprising at least one foam layer comprising therapeutic agent wherein the therapeutic agent is eluted from the foam (abstract; ¶ 0010; claim 14). The foam layers have benefit and advantage of absorbing the wound exudate while delivering therapeutic agent to the wound (¶ 0009). Suitable foam material includes polyurethane (¶ 0029; claims 1, 7). The reference teaches multiple foam layers comprising different densities, different swelling properties and different porosities that are stacked with each other without adhesive by curing or by adhesive. Further, Patel teaches casting or extruding the layers together, and casting and extrusion will provide two layers stacked together, and adhesive is another alternative to casting or extrusion, and not required, therefore, the layers are directly stacked on top of each other. The layers are stacked on each other and are bond by curing without adhesive. (¶¶ 0036, 0040, 0042, 0045, 0051). The foams provide controlled release of therapeutic agents including antimicrobial agents, anti-inflammatory agents, hemostatic agents, would healing agents, etc. (¶ 0054).
Hissink teaches biodegradable polymer foam for tissue regeneration and drug delivery purposes that further can be applied to the wound as wound dressing, absorbent foam, or applied at body antrum, e.g. nasal cavity, used as hemostatic sponge, e.g. laparotomy sponge, used as post-surgery dressing to prevent tissue adhesion, and can be dental surgery and after tooth extraction. The foam has advantage that it does not have to be mechanically removed (abstract; page 15, lines 22-25; page 16, lines 1-10; page 37, line 30; page 38, lines 1-12; page 48, lines 28-30; claim 32). The biodegradable foam has enough strength to be readily handled in surgical procedures, high elasticity, absorbs body fluid, comfortable, fits into any topography or space, resilient, and soft to avoid injury to sensitive tissues (page 3, lines 15-28). The biodegradable polymer foam comprises phase separated polymer consisting of an amorphous segment and crystalline segment, wherein the amorphous segment comprises a hydrophilic segment. The hydrophilic amorphous segment comprises polyethylene glycol (page 4, lines 321; page 6, lines 20-23). The biodegradable polymer foam having the formula:
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58
447
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wherein R is selected from one or more aliphatic polyesters, polyetheresters, polyethers, polyanhydrides and/or polycarbonates, and at least one R 15 comprises a hydrophilic segment, R1 and R" are independently C2-C8 alkylene, optionally substituted with C1-C10 alkyl or C1-C10 alkyl groups substituted with protected S, N, P or O moieties and/or comprising S, N, P or O (e.g. ether, ester, carbonate and/or anhydride groups) in the alkylene chain, Z1-Z4 are independently amide, urea or urethane, Q1 and Q2 are independently urea, 20 urethane, amide, carbonate, ester or anhydride, n is an integer from 5-500, p and q are independent 0 or 1, provided that when q is 0, R is a mixture of at least one crystalline polyester, polyetherester or polyanhydride segment and at least one amorphous aliphatic polyester, polyether, polyanhydride and/or polycarbonate segment. The O containing moieties in the alkylene chain, if 25 present, are preferably hydrophilic groups, in particular ether groups (pages 5-6; and claims 1-3). The reference discloses impregnation of the foam with various active substances that can be released in controllable manner upon wetting, such as hemostatic substances (page 37, lines 20-26). The reference teaches porosity of the biodegradable foam polymer preparation from 58-99%, and preferably from 92-95%, more preferably 95-98% (page 21, lines 1-5), and exemplifies 96.4% (page 42, example 9). Further the absorbent foam absorbs blood and provides hemostasis (page 19, lines 29-30). The reference teaches method of making the phase separated foam including the steps of dissolving the polymer in a solvent, completely removing solvent by freeze drying (page 35, lines 3-14, 20-23; and page 37, lines 20-30).
Ascertainment of the Difference Between Scope the Prior Art and the Claims
(MPEP §2141.012)
While Patel teaches wound dressing comprising multiple polyurethane foam layers to deliver therapeutic agents to the wound including hemostatic agent and to absorb wound fluid, the reference however does not teach the claimed foam comprising phase-separated polymer comprising at least one amorphous segment and at least one crystalline segment as claimed by claim 13. The missing element from Patel is taught by Hissink.
While Hissink teaches the phase separated foam useful for wound dressing and for drug delivery to the wound including hemostatic agent, and useful to absorb wound fluid, e.g. blood, the reference does not explicitly teach multilayered foam as instantly claimed by claim 13. The missing element from Hissink is taught by Patel.
Patel and Hissink do not teach the foam layers are directly stacked on top of each other as claimed by claim 13. This missing element is taught by CA ‘291.
While Patel and Hissink suggest the presence of the active agent in the wall of the foam, the references do not explicitly teach the voids of the foam do not contain active agents as instantly claimed by claim 13.
CA ‘291 teaches improved medical devices having improved method of treating patients and improved method for delivering therapeutic agents (page 5 first two paragraphs). The devices can be implants, hemostatic devices, medicated devices etc. (page 9, first paragraph). The device can be foam (page 11, last paragraph). The device is multilayered of same material but having different biocompatibility and different biodegradation, and different additives that are coated on each other, i.e. stacked on top of each other, and are dried for shape fixation (page 14, first full paragraph).
Pauletti teaches polymer foam for controlled and sustained delivery of therapeutic agents to and through body cavities as the foam breakdown, e.g. nasal cavity. The foam is absorbable or biodegradable and incorporates therapeutic agent that is released from the foam upon placement of the foam on the epithelial surface of the nose for example. The active agent includes anti-inflammatory agents (abstract; page 6, lines 1-7; page 8, lines 17-26; page 10, lines 27-32; page 15, lines 21-27; page 20, lines 33-35; page 35, lines 6-11). The process of making the polymer foam includes the steps of dissolving a mixture of the polymers and therapeutic agent(s) in a solvent and additive. The mixture is freeze dried to completely evaporate the solvent and form the pores of the foam (page 15, line 29 till page 16, line 24; page 23, line 12 till page 24 line 3). Additives can be added to the lyophilized foam (page 19, lines 28-35).
Chandrashekhar teaches hemostatic biodegradable foam composition comprising chitosan and phase separated polymer. The foam has porosity of 85-99%. The foam accelerates clotting process of blood when applied topically to the bleeding
surface. The foam useful for hemostasis in body cavities even chitosan is used in small
amount. The reference teaches process of making the foam comprising the steps of dissolving the phase separating polymer in a solvent to form polymer solution, blending the hemostatic agent in the polymer solution, removing the solvent by freeze-drying. The hemostatic agent is homogeneously distributed throughout the foam and adheres to the foam and provides the foam with its hemostatic properties. The interaction of the polymer and the hemostatic agent in the foam leads to a synergetic effect with respect to the hemostatic activity, in particular when using a phase-separated polymer, even more in particular when using a chitosan hemostatic agent and a phase-separated polymer. Polymer foams having a porosity of 85-99% and a foam density of 0.01-0.2 g/cm³ are capable of absorbing blood, but generally have no hemostatic activity of itself.
Hemostatic agents are capable of hemostatic activity when applied to a wound in a sufficient amount. The inventors found that a foam comprising a blend of a hemostatic agent and a polymer that provides the foam with the above-defined porosity and foam density was found to be capable of rapid blood coagulation, even when the hemostatic agent is present in the foam at low concentrations. The polymer is believed to provide the foam with such mechanical (compressibility, strength, and absorption), structural
(area/volume ratio) and chemical properties (hydrophilic/hydrophobic) that the hemostatic agent shows an enhanced hemostatic activity. In particular porosity and density are considered important to achieve this enhanced hemostatic activity. (See abstract; page 1, lines 1-14; page 2, lines 20-25; page 3, lines 6-25; pages 20-22; claims).
Finding of Prima Facie Obviousness Rational and Motivation
(MPEP §2142-2143)
Therefore, it would have been obvious to one having ordinary skill in the art before the effective filing date of the present invention to provide wound dressing comprising multiple foam layers comprising polyurethane foam and therapeutic agent that is applied to the wound to elute therapeutic agent and absorb wound fluid as taught by Patel, and replace the polyurethane foam with the biodegradable polymer foam taught by Hissink that comprises at least one amorphous segment and at least one crystalline segment to form the multiple layers of foam in the dressing of Patel. One would have been motivated to do so because Hissink teaches such phase separated polymer foam can be applied to the wound with advantage that it does not have to be mechanically removed and has enough strength to be readily handled in surgical procedures, comfortable, fits into any topography or space, resilient, absorb body fluid, deliver active agent in a controlled manner, and soft to avoid injury to sensitive tissues. One would reasonably expect formulating wound dressing comprising multiple foam biodegradable layers comprising phase separated polymer that is soft, porous, resilient and safe to the surrounding tissues while delivering therapeutic agents to the wound and absorbing body fluid.
Alternatively, it would have been obvious to one having ordinary skill in the art before the effective filing date of the present invention to provide biodegradable phase separated polymer foam included in a wound dressing to deliver therapeutic agent and to absorb wound fluid as taught by Hissink, and provide the foam in the dressing in multiple layers as taught by Patel. One would have been motivated to do so because Patel teaches multilayered foam can provide different properties by each layer such as porosity, density, swelling property and elute therapeutic agents in controlled manner while absorbing wound fluid. One would reasonably expect formulating wound dressing comprising multilayered biodegradable phase separated polymer foam to deliver therapeutic agent to wound in a controlled manner while absorbing body fluid.
Further, optionally, one having ordinary skill in the art would have provided multilayered device having stacked layers that can be foam layered as taught by CA ‘291 because CA ‘291 teaches that such medical devices are improved medical devices having improved method of treating patients and improved method for delivering therapeutic agents and fixed shape.
Furthermore, one having ordinary skill in the art would have used the process of producing the foam taught by Pauletti comprising mixture of polymer and active agent that undergoes freeze drying to create the voids of the foam and eventually maintaining the active agent in the wall of the foam. One would have been motivated to do so because Pauletti teaches such a method provides foam for controlled and sustained delivery of active agents to and through body cavities as the foam breakdown upon placement of the foam on the epithelial surface.
Additionally, one having ordinary skill in the art would have been motivated to freeze drying solution comprising the phase-separated foam and hemostatic agent as taught by Chandrashekhar to obtain homogenous distribution of the hemostatic agent into the foam and its adherence into the foam while obtaining hemostasis in body cavities even with small amount of hemostatic agent.
Regarding claim 13, the claimed drug eluting phase separating polymer foam is taught by combination of Patel and Hissink that teaches release of therapeutic agent from the foam; i.e. drug eluting foam.
Regarding claim 13 that the amorphous segment optionally comprises hydrophilic segment, Hissink teaches this limitation.
Regarding the multilayered device as claimed by claim 13, Patel teaches multilayered foam in a wound dressing. Further, Patel teaches casting or extruding the layers together, and casting and extrusion will provide two layers stacked together, and adhesive is another alternative to casting or extrusion, and not required, therefore, the layers are directly stacked on top of each other. The layers are stacked on each other and are bond by curing without adhesive. Combination of Hissink and Patel teaches extruding or casting two layers together of phase separated polymer that are directly stacked and expected to form a strong bond.
Regarding the limitation of claim 13 that “wherein the at least two foam layers each individually has porosity of 85-99%”, Patel teaches two separate foam layers laminated to each other having porosity and Hissink teaches porosity of the foam from 85-99%, and one having ordinary skill in the art would have made the two porous layers of Patel each have porosity within the porosity taught by Hissink to achieve soft foam to absorb body fluid, deliver active agent in a controlled manner, and to avoid injury to sensitive tissues.
Regarding the limitation of claim 13 that the drug is substantially located in the wall of the foam and not the voids before degradation of the polymer and eluted upon degradation of the polymer, Patel clearly teaches plurality of dissolvable members disposed and distributed within the foam, i.e. within the wall itself, and therapeutic agent is associated with the dissolvable members or present as dissolvable salts, and upon dissolution of the dissolvable members or salts, the therapeutic agent is eluted from the foam and released and voids are created in the foam and are left behind. This teaching implies the presence of the drug distributed in the wall of the foam, and released upon wetting the foam on use due to formation of pores. This is exactly what applicants had done, release of drug upon degradation of the foam. Further, Pauletti teaches the method applicants used to produce the foam comprising incorporating the active agent with the polymer then creating the voids by freeze drying, and the active agent is released upon degradation of the polymer. Further, Chandrashekhar teaches homogenous distribution of the hemostatic agent into the foam and its adherence into the foam while obtaining hemostasis in body cavities even with small amount of hemostatic agent. Therefore, the hemostatic agent is in the wall of the foam and not the cavities of the foam at the time of production and prior to its degradation.
Regarding stacking of the foam layers as claimed by claim 13, this is taught by Patel and CA ‘291.
Regarding the properties claimed by claim 14, Patel teaches multiple foam layers having different functions, e.g. porosities, densities, and swelling properties. Further, Chandrashekhar teaches the claimed properties.
Regarding the biodegradable polymers claimed by claim 15, both Patel and Hissink teach polyurethane.
Regarding the formula of the phase separated polymer claimed by claim 16, the claimed formula is taught by Hissink.
Regarding the process of making the foam claimed by claim 17, the claimed steps are taught by Hissink and Chandrashekhar including the steps of dissolving the polymer in solvent, mixing with active agent and freeze drying. Note that the process of making the foam does not impart patentability to product claims.
Regarding the active agents claimed by claim 18, Patel and Pauletti teach anti-inflammatory drugs and antimicrobial drugs, and both Patel, Hissink and Chandrashekhar each teaches hemostatic agent.
Regarding the intended use of the claimed foam as claimed by claim 24, Patel and Hissink teaches polymer foam for controlled delivery of therapeutic agents and absorb body fluid, i.e. drainage, and Hissink teaches biodegradable polymer foam for tissue regeneration and drug delivery purposes that can be applied at body antrum, e.g. nasal cavity.
Absent any evidence to the contrary, and based upon the teachings of the prior art, there would have been a reasonable expectation of success in practicing the instantly claimed invention. Therefore, the invention as a whole would have been prima facie obvious to one of ordinary skill in the art before the effective filing date of the present invention.
Claim 25 is rejected under 35 U.S.C. 103 as being unpatentable over Patel in view of Hissink, or alternatively, Hissink in view of Patel, and further optionally combined with CA ‘291 and Pauletti, and combined with Chandrashekhar as applied to claims 13-18 and 24 above, and further in view of either the article by Hong et al. (Systemic effect and safety of triamcinolone-impregnated nasal packing after endoscopic sinus surgery: A randomized, double-blinded, placebo-controlled study) or the article by Lavigne et al. (Steroid eluting sinus implant for in-office treatment of recurrent nasal polyposis: a prospective, multicenter study), all references are of record.
Applicant Claims
Claim 25 recites the drug comprises steroidal anti-inflammatory agent and a hemostatic agent.
Determination of the Scope and Content of the Prior Art
(MPEP §2141.01)
The combined teachings of Patel and Hissink, and optionally CA ‘291 and further optionally combined with Pauletti, and combined with Chandrashekhar are previously discussed in this office action.
Ascertainment of the Difference Between Scope the Prior Art and the Claims
(MPEP §2141.012)
Patel, Hissink and Chandrashekhar teach hemostatic agents in their products, and Patel and Pauletti teach anti-inflammatory agent, however the reference does not explicitly teach steroidal anti-inflammatory agent as claimed by claim 25.
Hong teaches absorbable nasal dressing infused with triamcinolone (steroidal anti-inflammatory corticosteroid) after endoscopic nasal surgery to improve wound healing and to reduce recurrence of polyps. The reference teaches topical administration of corticosteroids is superior to systemic administration because this localizes their effect and minimizes their systemic side effects (see the entire document, and in particular the abstract and discussion).
Lavigne teaches steroid eluting implant can safely, feasibly and efficiently placed in patient with recurrent rhinosinusitis for treating obstructive polyposis (see provided abstract).
Finding of Prima Facie Obviousness Rational and Motivation
(MPEP §2142-2143)
Therefore, it would have been obvious to one having ordinary skill in the art before the effective filing date of the present invention to provide biodegradable phase separating polymer foam comprising active agent including anti-inflammatory agent and hemostatic agent for use in the nasal cavity to release the active agents in controlled release rate as taught by the combination of Patel, Hissink, and optionally CA ‘291, and optionally Pauletti, and further combined with Chandrashekhar, and replace the anti- inflammatory agent by steroidal anti-inflammatory agent taught by any of Hong or Lavigne. One would have used steroidal anti-inflammatory agent because Hong teaches steroidal anti-inflammatory agents improve wound healing and reduce recurrence of polyps after endoscopic nasal surgery while minimizing systemic side effects of steroidal anti-inflammatory agents, and because Lavigne teaches that steroid eluting implant can safely, feasibly and efficiently placed in patient with recurrent rhinosinusitis for treating obstructive polyposis. One would reasonably expect formulating biodegradable foam comprising phase separating polymer comprising steroidal anti-inflammatory agent and hemostatic agent to be delivered in a controlled rate when used in the nasal cavity after surgery wherein healing and hemostasis of the nasal cavity after surgery is improved.
Absent any evidence to the contrary, and based upon the teachings of the prior art, there would have been a reasonable expectation of success in practicing the instantly claimed invention. Therefore, the invention as a whole would have been prima facie obvious to one of ordinary skill in the art before the effective filing date of the present invention.
Response to Arguments
Applicant's arguments filed 04/24/2026 have been fully considered but they are not persuasive.
Claim Rejections - 35 U.S.C. 103
The focus of applicants argument in “Prong 1” and “Prong 2” in pages 8 and 9 of the response filed 04/24/2026 is that the cited references do not teach active agent present in the wall of the foam and not in the void before degradation of the polymer.
This argument is moot in view of the newly cited references to Chandrashekhar that clearly teaches the presence of hemostatic agent (chitosan) in the polymer forming the foam and not in the void at the time the foam is formed.
A) Patel Does Not Teach the Pre-Degradation State Required by Amended Claim 13
Applicants argue that Patel teaches that the foam comprises a plurality of dissolvable members disposed and distributed within the foam, i.e. within the wall itself, and the therapeutic agent is associated with the dissolvable members or present as dissolvable salt, and upon dissolution of the dissolvable members or salt, the therapeutic agent is eluted and released and voids are created in the foam and are left behind (OA, bottom p. 4). This teaching describes two, and only two, states of the Patel foam: State 1 (pre-dissolution): The foam matrix contains dissolvable members (e.g., dissolvable beads, salt crystals, or alginate particles) embedded within it. State 2 (post-dissolution): The dissolvable members have dissolved, creating voids. The therapeutic agent, which was associated with the dissolvable members, is now located in those voids - not in the wall. Accordingly, in State 2, the foam also does not have the structure required by amended claim 13, because the drug is in the voids, not in the wall. Patel does not describe any such intermediate state. The dissolvable members are the drug-delivery vehicle in Patel: once they dissolve, the drug is released into the resulting voids and from there to the wound. There is no teaching in Patel of a foam that, in its pre-use, pre-degradation state, already has open voids and a wall in which the drug is embedded.
In response to this argument, it is argued the newly cited reference to Chandrashekhar clearly teaches the presence of hemostatic agent (chitosan) in the phase separated polymer forming the foam and not in the void at the time the foam is formed. The reference does not teach dissolvable member (state 1), nor the release of active agents from the void following dissolution of the dissolvable member (state 2). The reference clearly teaches the hemostatic active agent adhered to the polymer foam, and provides the foam with its hemostatic activities. The reference does not teach of any states 1 or 2 above. The reference teaches interaction of the polymer and the hemostatic agent in the foam leads to a synergetic effect with respect to the hemostatic activity, in particular when using a phase-separated polymer, even more in particular when using a chitosan hemostatic agent and a phase-separated polymer. Polymer foams having a porosity of 85-99% and a foam density of 0.01-0.2 g/cm³ are capable of absorbing blood, but generally have no hemostatic activity of itself. Hemostatic agents are capable of hemostatic activity when applied to a wound in a sufficient amount. The inventors found that a foam comprising a blend of a hemostatic agent and a polymer that provides the foam with the above-defined porosity and foam density was found to be capable of rapid blood coagulation, even when the hemostatic agent is present in the foam at low concentrations. The polymer is believed to provide the foam with such mechanical (compressibility, strength, and absorption), structural (area/volume ratio) and chemical properties (hydrophilic/hydrophobic) that the hemostatic agent shows an enhanced hemostatic activity. In particular porosity and density are considered important to achieve this enhanced hemostatic activity.
The examiner respectfully maintains that the location of the active agent within the foam is determined by the material used and process of its production, as applicants described in page 3, lines 6-14. The process of making the foam is not claimed, and does not impart patentability to the claimed product. Note that Chandrashekhar used the claimed polymer and the claimed hemostatic agent chitosan.
B) Pauletti Cannot Cure the Deficiency of Patel, and the Combination Remains Inoperable
Applicants argue that, if even, arguendo, Pauletti's lyophilization process, applied to Pauletti's own polymers, results in a drug-in-wall architecture, this would still not render the invention obvious. That is, applying Pauletti's freeze-drying process to Patel's dissolvable-member system - is technically inoperable and would destroy the very feature of Patel that the examiner relies upon. The person of ordinary skill in the art will understand that if the dissolvable members or salts of Patel are already dissolved in the foam production process as taught by Pauletti, they will disintegrate by dissolution and will not be reformed after the freeze-drying step. That is, the dissolvable beads, salt crystals, and particles will not reform after dissolution and freeze-drying. Instead, after freeze-drying, they will remain disintegrated and will have lost their intended purpose to be able to elute the antimicrobial agent and to form voids upon dissolution.
In response to this argument, the argument above regarding the newly cited reference to Chandrashekhar is hereby reiterated. The process of making the foam does not impart patentability to the claims. The claimed product taught by combination of the cited references, and using chitosan as hemostatic active agent with the phase separated polymer led to adherence hemostatic agent to the foam and not dissolved in the voids of the foam as taught by Chandrashekhar. Pauletti is currently relied upon as an optional reference. The combination of the cited references, with or without Pauletti, does not cause the active agent particles to disintegrate and lose their purpose because the active agent particles are adherent to the foam walls.
Applicants argue that, even if one were to accept the Examiner's characterization of the combination, the resulting product would still not meet the requirements of amended claim 13. Pauletti's polymers are hydrophilic, water-soluble polymers: "For lyophilized foams, one starts with a solution of polymers and additives, and normally at least one polymer is water-soluble." (Pauletti, p. 25, 1. 10-15). The drug release mechanism in Pauletti is dissolution-based, not degradation-based: physical and chemical properties of foams of the invention can be tailored to optimize their intended use, which is achieved by controlling the rate of release of the pharmacologically active agents incorporated into foams with said compositions, and drug release from the delivery device can occur by diffusion or erosion, or by a combination of both, leading to immediate, controlled, or pulsed delivery of the agent (Pauletti, p. 17, 1. 22-30).
In response to this argument, it is argued that all the elements of the claimed product are taught by combination of the cited references, as set forth in this office action.
C) The Combined Teachings Fail to Disclose the Pre-Degradation Structural State Required by Amended Claim 13
Applicants argue that taking the combined teachings of Patel, Hissink, CA '291, and Pauletti as a whole, there is no disclosure of a foam that, in its pre-degradation state, independently comprises (i) pre- existing voids and (ii) a wall in which the drug is located and not in the voids, such that the drug elutes upon degradation of the polymer.
In response to this argument, it is argued that the present claims are directed to a product, and the elements of the claimed product, even its process of making, and the used hemostatic agent and polymers are taught by combination of the cited references. No teaching of release of the active agent before degradation of the polymer as claimed. All properties and behavior of the claimed product taught by combination of the cited references are expected to be the same achieved by the prior art since materials and their properties cannot have mutually exclusive characteristics.
The rational to modify or to combine the prior art does not have to be expressly stated in the prior art; the rational may be expressly or impliedly contained in the prior art or it may be reasoned from knowledge generally available to one of ordinary skill in the art. The reason or motivation to modify the reference may often suggest what the inventor has done, but for a different purpose or to solve different problem. It is not necessary that the prior art suggest the combination or modification to achieve the same advantage or result discovered by applicant. In re Linter, 458 F.2d 1013, 173 USPQ 560 (CCPA 1972).
Obviousness does not require absolute predictability of success all that is required is a reasonable expectation of success. See In re Kubin, 561 F.3d at 1360. The Court has held that "the test of obviousness is not express suggestion of the claimed invention in any or all of the references but rather what the references taken collectively would suggest to those of ordinary skill in the art presumed to be familiar with them." See In re Rosselet, 146 USPQ 183, 186 (CCPA 1965). "There is no requirement (under 35 USC 103(a)) that the prior art contain an express suggestion to combine known elements to achieve the claimed invention. Rather, the suggestion to combine may come from the prior art, as filtered through the knowledge of one skilled in the art." Motorola, Inc. v. Interdigital Tech. Corp., 43 USPQ2d 1481, 1489 (Fed. Cir.1997). An obviousness determination is not the result of a rigid formula disassociated from the consideration of the facts of a case. Indeed, the common sense of those skilled in the art demonstrates why some combinations would have been obvious where others would not. See KSR Int'l Co. v. Teleflex Inc., 82 USPQ2d 1385 (U.S. 2007) ("The combination of familiar elements according to known methods is likely to be obvious when it does no more than yield predictable results.").
Finally, it is well established that the claims are given the broadest interpretation during examination. A conclusion of obviousness under 35 U.S.C. 103 (a) does not require absolute predictability, only a reasonable expectation of success; and references are evaluated by what they suggest to one versed in the art, rather than by their specific disclosure. In re Bozek, 163 USPQ 545 (CCPA 1969).
In the light of the foregoing discussion, the Examiner’s ultimate legal conclusion is that the subject matter as a whole as defined by the claims would have been prima facie obvious within the meaning of 35 U.S.C. 103 (a).
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Isis A D Ghali whose telephone number is (571)272-0595. The examiner can normally be reached on Monday through Friday, 8:30 AM to 5:00 PM EST.
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/ISIS A GHALI/Primary Examiner, Art Unit 1611
/I.G./
