DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Response to Arguments
Applicant's arguments, filed March 3, 2026, have been fully considered but they are not deemed to be fully persuasive. The following rejections and/or objections constitute the complete set presently being applied to the instant application.
Specification
The disclosure is objected to because of the following informalities:
Although Applicants amended the specification filed March 3, 2026, the issues identified in the December 5, 2025 Office Action regarding the use of the terms that are a trade name or a mark used in commerce have not been fully resolved. Applicants included a proper symbol indicating use in commerce but did not add the corresponding generic terminology for OmunipaqueTM. The terms should be accompanied by appropriate generic terminology. Therefore, the specification remains objected to.
Although the use of trade names and marks used in commerce (i.e., trademarks, service marks, certification marks, and collective marks) are permissible in patent applications, the proprietary nature of the marks should be respected and every effort made to prevent their use in any manner which might adversely affect their validity as commercial marks.
Appropriate correction is required.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
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 21, 25-27, and 40 are rejected under 35 U.S.C. 103 as being unpatentable over Seo (KR 100877696; all citations from the machine translation) in view of Makadia et al. (Polymers 2011).
This rejection is MAINTAINED for the reasons of record set forth in the Office Action mailed December 5, 2025 and those set forth herein.
Regarding new limitations of amended claim 21, the biodegradable polymer comprises a hydrophobic biodegradable polymer and a hydrophilic biodegradable polymer (previously recited in canceled claim 22); the hydrophobic biodegradable polymer consists of one or more selected from polylactic acid (PLA) and polycaprolactone (PCL) (previously recited in canceled claim 23); and the hydrophilic biodegradable polymer consists of one or more selected from poly(lactic-co-glycolic acid) (PLGA) and caprolactone-co-glycolic acid (PCGA) (previously recited in canceled claim 24), these limitations are derived from canceled claims 22-24 and the claims were rejected over Seo in view of Makadia as discussed in the Office Action mailed December 5, 2025. Regarding new limitation of amended claim 21, the weight mixing ratio of the hydrophobic biodegradable polymer to the hydrophilic biodegradable polymer is 0.33 to 3.0, Seo discloses the Pluronic® block copolymer composed of hydrophilic polyethylene oxide (PEO) and hydrophobic polypropylene oxide(PPO) (page 6, ¶ 2). Seo discloses that the polymer can exist in various form depending on the ratio of PEO and PPO, and that the hydrophobicity increases as the hydrophilic PEO ratio decreases or the hydrophobic PPO ratio increases (page 6, ¶ 2; Table 1 in original document). For example, Pluronic® L64 in Table 1 in original document contains approximately 60% hydrophobic and 40% hydrophilic components by weight, meaning the weigh mixing ratio of the hydrophobic polymer to the hydrophilic polymer is 1.5,which reads on the weight mixing ratio of the hydrophobic polymer to the hydrophilic polymer is 0.33 to 3.0 in instant claim 21. It would be expected that the weight mixing ratio of the hydrophobic biodegradable polymer such as PLA and PCL to the hydrophilic biodegradable polymer such as PLGA and PCGA could be adjusted to be 1.5, as Seo teaches that the weigh mixing ratio of the hydrophobic polymer to the hydrophilic polymer can be 1.5. Further, it would have been a matter of routine optimization to adjust the weight mixing ratio to achieve desired hydrophobicity levels according to specific application requirements, as Seo teaches that various polymers with different hydrophobicities can be prepared by adjusting the weight mixing ratio.
New claim 40 is an intended use claim. The recitation of an intended use for a composition does not limit the scope of a product claim to that specific use unless the intended use results in a structural difference between the claimed invention and the prior art. The intended use of polymeric embolic material to allow for recanalization after one or two weeks is of no patentable significance to the structure. Patentability is determined by the composition’s structure, not its intended use. As discussed above, the embolic materials of Seo in view of Makadia are structurally the same as the claimed embolic materials and the embolic materials of Seo in view of Makadia are inherently capable of the use recited in claim 40. Because the intended use does not distinguish the claimed composition from the prior art and the prior art composition is structurally the same as the claimed composition, the recitation of the intended use in claim 40 has no patentable weight. Accordingly, claim 40 is obvious.
Applicant argues that Seo fails to render the pending claims obvious because Seo disclose a single polymer or a block copolymer which is fundamentally different from the claimed mixture of two separate polymers at a defined weight mixing ratio of 0.33 to 3.0. Applicant argues that Makadia does not teach or suggest blending two separate polymers at a specific weight mixing ratio of 0.33 to 3.0.
This argument is unpersuasive. Seo teaches block copolymers comprising hydrophobic polymers and hydrophilic polymers such as Pluronic® L64 and PEGylated PLA. Instant claim 21 recites that the polymer comprises a hydrophobic polymer and a hydrophilic polymer and the block copolymer of Seo comprises hydrophobic and hydrophilic polymer segments. Neither claims nor the specification requires that the polymer should be a mixture or blend of two distinct polymers. The broadest reasonable interpretation of instant claims in view of the specification encompasses not only polymer blends but also block copolymers. As discussed above, Seo teaches that the weight ratio of the hydrophobic polymer to the hydrophilic polymer can vary, and the weigh mixing ratio can be 1.5 (page 6, ¶ 2; Table 1 in original document). Further, it would have been a matter of routine optimization to adjust the weight mixing ratio to achieve desired hydrophobicity levels according to specific application requirements, as Seo teaches that various polymers with different hydrophobicities can be prepared by adjusting the weight mixing ratio. As discussed in the Office Action mailed December 5, 2025, a person of ordinary skill in the art would have been motivated to use hydrophilic PLGA instead of the PEG in PEGylated PLA because Seo teaches that PLGA can be used as a biodegradable polymer and Makadia teaches that PLGA can be used as a hydrophilic polymer. Further, a person of ordinary skill in the art would have been motivated to use PLGA instead of PEG in order to tune hydrophobicity.
Claims 28 and 32-34 are rejected under 35 U.S.C. 103 as being unpatentable over Seo and Makadia as applied to claims 21, 25-27, and 40 above, further in view of Shea (US 2006 0002978).
This rejection is MAINTAINED for the reasons of record set forth in the Office Action mailed December 5, 2025 and those set forth herein.
Regarding new limitations of amended claim 28, the biodegradable polymer comprises a hydrophobic biodegradable polymer and a hydrophilic biodegradable polymer (previously recited in canceled claim 29); the hydrophobic biodegradable polymer consists of one or more selected from polylactic acid (PLA) and polycaprolactone (PCL) (previously recited in canceled claim 30); and the hydrophilic biodegradable polymer consists of one or more selected from poly(lactic-co-glycolic acid) (PLGA) and caprolactone-co-glycolic acid (PCGA) (previously recited in canceled claim 31), these limitations are derived from canceled claims 29-31 and the claims were rejected over Seo in view of Makadia and Shea as discussed in the Office Action mailed December 5, 2025. Regarding new limitation of amended claim 28, the weight mixing ratio of the hydrophobic biodegradable polymer to the hydrophilic biodegradable polymer is 0.33 to 3.0, Seo discloses that the weight mixing ratio can be 1.5 as discussed above.
Applicant argues that there is no motivation to apply Shea’s teachings because Shea is directed to an entirely different technical field and Shea does not teach any specific weight mixing ratio between hydrophobic and hydrophilic polymers.
This argument is unpersuasive. A reference is analogous art to the claimed invention if: (1) the reference is from the same field of endeavor as the claimed invention (even if it addresses a different problem); or (2) the reference is reasonably pertinent to the problem faced by the inventor (even if it is not in the same field of endeavor as the claimed invention). See MPEP § 2141.01(a). Shea discloses biodegradable polymer materials used for the controlled delivery and release of biological materials in vivo, which is analogous to the polymer embolic materials used for the controlled delivery and release of drugs in vivo. Accordingly, Shea is analogous art because it is reasonably pertinent to the problem faced by the inventor. As discussed above, Seo teaches that the weight ratio of the hydrophobic polymer to the hydrophilic polymer can be 1.5. As discussed in the Office Action mailed December 5, 2025, a person of ordinary skill in the art would have been motivated to apply the teachings of Shea to the nanoparticles of Song and Makadia to make a hydrophilic PLGA-hydrophobic PLGA in order to increase flexibility in tuning hydrophobicity.
Claim 38 is rejected under 35 U.S.C. 103 as being unpatentable over Seo and Makadia as applied to claims 21, 25-27, and 40 above, further in view of Duran et al. (Theranostics, 2016; cited on IDS filed Aug 22, 2023).
In addition to the teachings of Seo discussed above, Seo discloses nanoparticles comprising a Lipiodol® core and a biocompatible polymer film surrounding the core (claim 1). The Lipiodol®, an oil-based radiographic contrast medium made from poppy seed oil, is a drug widely known in clinical practice as an embolizing agent (page 5, ¶ 2), reads on an oil-base contrast agent of instant claim 21. Seo discloses that the weight ratio of the biocompatible polymer and Lipiodol® can be 1:0.5 to 1 (polymer weight:Lipiodol® weight) (page 14, ¶ 1; claim 4), reads on a weight mixing ratio of the oil-based contrast agent to the biodegradable polymer being 1.0 to 2.0 of instant claim 21. Seo discloses that commercially available Pluronic® block copolymer can be used to encapsulate Lipiodol® (page 6, ¶ 2; page 19, Example 2). Seo further discloses that the biocompatible polymers can be a PEGylated PLA (polylactic acid) (page 6, ¶ 1; claim 2) which is a biodegradable diblock copolymer comprising a hydrophilic biodegradable polyethylene glycol (PEG) and a hydrophobic biodegradable PLA. Seo discloses that the biocompatible polymers can be poly(lactic-co-glycolic acid) (PLGA) (page 6, ¶ 1; claim 2).
Makadia discloses the presence of methyl side groups in PLA makes it more hydrophobic than poly glycolic acid (PGA) and hence lactide rich PLGA copolymers are less hydrophilic compared to the PLGA copolymers having less amount of lactide (page 1379, Lines 6-7).
Neither Seo nor Makadia discloses that the embolic material has an average particle size of 100 to 500 µm.
Duran discloses a radiopaque bead for transarterial embolization (title). Duran discloses that the average size of the bead can vary with different physical properties, providing specific examples such as a 164 µm bead, (page 34, Tables 1 and 2).
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to modify the embolic materials of Seo and Makadia to incorporate a particle size of 164 µm. A person of ordinary skill in the art would have been motivated to make those modifications and reasonably would have expected success because Duran teaches that the microspheres for embolization can have a 164 µm diameter. Further, a person of ordinary skill in the art would have been motivated to adjust the particle size according to specific clinical application requirements. Accordingly, applying the teachings of Duran to the embolic materials of Song and Makadia constitutes no more than the predictable use of prior art elements according to their established functions, thus rendering claim 38 obvious.
Claim 39 is rejected under 35 U.S.C. 103 as being unpatentable over Seo and Makadia as applied to claims 21, 25-27, and 40 above, further in view of Kim et al. (Chemical Communications, 2010; cited on IDS filed Aug 22, 2023).
Seo and Makadia are discussed above.
Neither Seo nor Makadia discloses that the embolic material has depressions on its surface.
Kim discloses PLGA microparticles with golf ball-like dimpled surface (abstract; Fig. 1) which reads on depressions on the surface of instant claim 39Kim discloses that the dimpled surface can have advantages of reducing the drag force exerted on the microparticles when they are necessary to move in the fluid, similar to a golf ball with dimple structures (page 7433, col. 1, ¶ 2).
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to modify the embolic materials of Seo and Makadia by fabricating dimples on the surface. A person of ordinary skill in the art would have been motivated to make those modifications and reasonably would have expected success because Kim teaches that the particles can have a dimpled surface. Further, a person of ordinary skill in the art would have been motivated to utilize a dimpled surface in order to improve the delivery of embolic materials comprising a contrast agent. Accordingly, applying the teachings of Kim to the embolic materials of Song and Makadia constitutes no more than the predictable use of prior art elements according to their established functions, thus rendering claim 39 obvious.
Claims 21, 25-27, 35, 37, and 40 are rejected under 35 U.S.C. 103 as being unpatentable over Nakanishi et al. (JP 2007 325910 A; cited on IDS filed Aug 22, 2023; all citations from the machine translation accompanying the office action mailed December 5, 2025) in view of Seo (KR 100877696 B1; all citations from the machine translation) and Makadia et al. (Polymers 2011).This rejection is MAINTAINED for the reasons of record set forth in the Office Action mailed December 5, 2025 and those set forth herein.
Regarding new limitations of amended claim 21, the biodegradable polymer comprises a hydrophobic biodegradable polymer and a hydrophilic biodegradable polymer (previously recited in canceled claim 22); the hydrophobic biodegradable polymer consists of one or more selected from polylactic acid (PLA) and polycaprolactone (PCL) (previously recited in canceled claim 23); and the hydrophilic biodegradable polymer consists of one or more selected from poly(lactic-co-glycolic acid) (PLGA) and caprolactone-co-glycolic acid (PCGA) (previously recited in canceled claim 24), these limitations are from canceled claims 22-24 and the claims were rejected over Nakanishi in view of Seo and Makadia as discussed in the Office Action mailed December 5, 2025.
Regarding new limitation of amended claim 21, the weight mixing ratio of the hydrophobic biodegradable polymer to the hydrophilic biodegradable polymer is 0.33 to 3.0, Nakanishi does not disclose the specific weight mixing ratio of the hydrophobic and hydrophilic polymers.
Seo is discussed above.
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to set a weight mixing ratio of the hydrophobic and hydrophilic polymers to 1.5 for the polymers of Nakanishi. A person of ordinary skill in the art would have been motivated to make these modifications and reasonably would have expected success because Seo teaches that the weight mixing ratio can be 1.5. Further, a person of ordinary skill in the art would have been motivated to adjust the weight mixing ratio to achieve desired hydrophobicity levels according to specific application requirements.
Claim 40 is an intended use claim. The recitation of an intended use for a composition does not limit the scope of a product claim to that specific use unless the intended use results in a structural difference between the claimed invention and the prior art. The intended use of polymeric embolic material to allow for recanalization after one or two weeks is of no patentable significance to the structure. Patentability is determined by the composition’s structure, not its intended use. As discussed above, the embolic materials of Nakanishi in view of Seo and Makadia are structurally the same as the claimed embolic materials and the embolic materials of Nakanishi in view of Seo and Makadia are inherently capable of the use recited in claim 40. Because the intended use does not distinguish the claimed composition from the prior art and the prior art composition is structurally the same as the claimed composition, the recitation of the intended use in claim 40 has no patentable weight. Accordingly, claim 40 is obvious.
Applicant argues that Nakanishi discloses a block copolymer rather than a mixture of two distinct polymers with the claimed weight ratio of 0.33 to 3.0 and that Nakanishi does not cure Seo’s or Makadia’s deficiencies. Applicant argues that the combination of the references fails to render the claims obvious.
This argument is unpersuasive. Nakanishi teaches block copolymers comprising hydrophilic polymer segment such as PEG and a hydrophobic polymer segment such as PLGA, and Seo teaches block copolymers comprising hydrophobic polymers and hydrophilic polymers such as Pluronic® L64 and PEGylated PLA. Instant claim 21 recites that the polymer comprises a hydrophobic polymer and a hydrophilic polymer, and the block copolymers of Nakanishi and Seo comprise hydrophobic and hydrophilic polymer segments. Neither claims nor the specification requires that the polymer should be a mixture or blend of two distinct polymers. The broadest reasonable interpretation of instant claims in view of the specification encompasses not only polymer blends but also block copolymers. As discussed above, Seo teaches the specific weight mixing ratio, and a person of ordinary skill in the art would have been motivated to apply the teachings of Seo and Makadia to the particles of Nakanishi. Such a combination would allow a person of ordinary skill in the art to select suitable polymers at a specific ratio according to the specific application requirements for use as embolic materials.
Claim(s) 28, 32-34 is/are rejected under 35 U.S.C. 103 as being unpatentable over Nakanishi, Seo, and Makadia as applied to claims 21, 25-27, 35, 37, and 40 above, further in view of Shea (US 2006 0002978 A1).
This rejection is MAINTAINED for the reasons of record set forth in the Office Action mailed December 5, 2025 and those set forth herein.
Regarding new limitations of amended claim 28, the biodegradable polymer comprises a hydrophobic biodegradable polymer and a hydrophilic biodegradable polymer (previously recited in canceled claim 29); the hydrophobic biodegradable polymer consists of one or more selected from polylactic acid (PLA) and polycaprolactone (PCL) (previously recited in canceled claim 30); and the hydrophilic biodegradable polymer consists of one or more selected from poly(lactic-co-glycolic acid) (PLGA) and caprolactone-co-glycolic acid (PCGA) (previously recited in canceled claim 31), these limitations are derived from canceled claims 29-31 and the claims were rejected over Nakanishi in view of Seo, Makadia, and Shea as discussed in the Office Action mailed December 5, 2025.
Regarding new limitation of amended claim 28, the weight mixing ratio of the hydrophobic biodegradable polymer to the hydrophilic biodegradable polymer is 0.33 to 3.0, Nakanishi does not disclose the specific weight mixing ratio of the hydrophobic and hydrophilic polymers.
Seo is discussed above.
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to set a weight mixing ratio of the hydrophobic and hydrophilic polymers to 1.5 for the polymers of Nakanishi. A person of ordinary skill in the art would have been motivated to make these modifications and reasonably would have expected success because Seo teaches that the weight mixing ratio can be 1.5. Further, a person of ordinary skill in the art would have been motivated to adjust the weight mixing ratio to achieve desired hydrophobicity levels according to specific application requirements.
Applicant argues that there is no motivation to combine the cited references to arrive at the specific weight mixing ratio as recited in the amended claims.
This argument is unpersuasive. As discussed above, Seo teaches the specific weight mixing ratio, and a person of ordinary skill in the art would have been motivated to apply the teachings of Seo, Makadia, and Shea to the particles of Nakanishi. Such a combination would allow a person of ordinary skill in the art to select suitable polymers at a specific ratio to optimize the degradation and controlled release profiles according to the specific application requirements for use as embolic materials.
Claim 38 is rejected under 35 U.S.C. 103 as being unpatentable over Nakanishi, Seo, and Makadia as applied to claims 21, 25-27, 35, 37, and 40 above, further in view of Duran et al. (Theranostics, 2016; cited on IDS filed Aug 22, 2023).
Nakanishi discloses a spherical particle produced by dispersing a solution of block copolymer and a contrast agent such as Lipiodol® (abstract; page 4, ¶ 12). Nakanishi discloses that the block polymer can be obtained by copolymerizing a hydrophilic polymer segment such as PEG and a hydrophobic polymer segment such as PLGA (page 4, ¶ 3). Nakanishi discloses a method for producing spherical particles by adding a block copolymer solution dropwise to an aqueous solution while maintaining specific stirring and flow rates (page 2, ¶ 10; page 5 ¶ 5).
Seo and Makadia are discussed above.
None of Nakanishi, Seo, and Makadia discloses that the embolic material has an average particle size of 100 to 500 µm.
Duran is discussed above.
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to modify the embolic materials of Nakanishi, Seo, and Makadia to incorporate a particle size of 164 µm. A person of ordinary skill in the art would have been motivated to make those modifications and reasonably would have expected success because Duran teaches that the microspheres for embolization can have a 164 µm diameter. Further, a person of ordinary skill in the art would have been motivated to adjust the particle size according to specific clinical application requirements. Accordingly, applying the teachings of Duran to the embolic materials of Nakanishi, Song, and Makadia constitutes no more than the predictable use of prior art elements according to their established functions, thus rendering claim 38 obvious.
Claim 39 is rejected under 35 U.S.C. 103 as being unpatentable over Nakanishi, Seo, and Makadia as applied to claims 21, 25-27, 35, 37, and 40 above, further in view of Kim et al. (Chemical Communications, 2010; cited on IDS filed Aug 22, 2023).
Nakanishi, Seo and Makadia are discussed above.
None of Nakanishi, Seo, and Makadia discloses that the embolic material has depressions on its surface.
Kim is discussed above.
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to modify the particles of Nakanishi, Seo, and Makadia by fabricating dimples on the surface. A person of ordinary skill in the art would have been motivated to make those modifications and reasonably would have expected success because Kim teaches that the particles can have a dimpled surface. Further, a person of ordinary skill in the art would have been motivated to adjust the particle size according to specific application requirements and to utilize a dimpled surface in order to improve the delivery of embolic materials comprising a contrast agent. Accordingly, applying the teachings of Kim to the embolic materials of Nakanishi, Song, and Makadia constitutes no more than the predictable use of prior art elements according to their established functions, thus rendering claim 39 obvious.
Conclusion
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 (37 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 JONG HWAN BAEK whose telephone number is (571)272-0670. The examiner can normally be reached Mon - Thu, 9 am - 3 pm ET.
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/JONG HWAN BAEK/Examiner, Art Unit 1618
/Nissa M Westerberg/Primary Examiner, Art Unit 1618
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