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 .
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.
Previous Rejections
Applicant’s arguments, filed March 2, 2026, have been fully considered. Rejections and/or objections not reiterated from previous office actions are hereby withdrawn. The following rejections and/or objections are either reiterated or newly applied. They constitute the complete set presently being applied to the instant application.
Restriction Requirement
Applicant's election with traverse of Group I, claims 1-10, in the response dated 3/2/2026, is acknowledged. The traversal is on the ground(s) that:
1. Restriction requirements are optional and he entire application, including Groups I, II, and III, can be examined without serious burden to the Examiner. The applicant further argues that the subject matter of Group I would likely yield the subject matter of Groups II and III; and
2. The Restriction Requirement requires additional costs to the applicant associated with the filing of multiple divisional applications in order to obtain protection for the claimed subject matter.
The Examiner acknowledges the arguments presented, but does not consider them persuasive for the following reasons:
As set forth in the Restriction Requirement dated 1/7/2026, each invention has attained recognition in the art as a separate subject for inventive effort, and also a separate field of search, including different classifications. Group II, for example, requires a second ionic or zwitterionic additive; such a limitation is not recited in the claims of Group I and would require a separate search. Group III, requiring a balloon medical device that is not recited in the inventions of either Group I or II, requires a search independent of the inventions of Groups I and II, for example of at least A61M 25/10.
The applicant also argues that additional costs may be incurred in view of a Restriction Requirement. The Examiner is again unpersuaded since the prosecution strategy requiring a restriction of independent inventions in a single application is outside of the purview of the Examiner; the strategy is determined only by the applicant and attorney. The legal basis for restriction is set forth in MPEP 803, and it does not appear that potential fees incurred by the applicant are a factor in determining the appropriateness of a restriction requirement
The requirement is still deemed proper and is therefore made FINAL.
Claims 11-20 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.
Claim Status
Claim 7 is cancelled.
Claims 1-6 and 8-20 are pending.
Claims 11-20 are withdrawn.
Claims 1-8 and 8-10 are examined on the merits in this prosecution.
CLAIM REJECTIONS
Obviousness Rejection
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.
1) Claims 1 and 3-10 are rejected under 35 U.S.C. 103 as being unpatentable over Akbari (US 2020/0129435 A1, of record), in view of Matson (US 2015/0024116 A1, of record).
Akbari teaches a composition comprising a matrix, a plurality of microparticles and a therapeutic agent, wherein the microparticles may be encapsulated (Abstract; pg 1, [0003]). Akbari teaches the microparticles may be encapsulated with PLGA polymer ([0003]), and the therapeutic agent may be doxorubicin, paclitaxel, or docetaxel (pg 1, [0004]), reading on claims 3 and 4.
Regarding the claim 1 limitation of “wherein the therapeutic agent is crystalline, partially crystalline, amorphous, partially amorphous, or a combination thereof,” it appears the claim is drawn to any solid form of therapeutic agent. As such, since it is known in the art that paclitaxel is a crystalline solid (mp 213-217 oC with decomposition).
For claim 5, Akbari teaches the microparticles may have a particle size of from 1 μM to 25 μM (pg 4, [0084), within the claimed range. For the active agent temozolomide (TMZ), an oral therapy for certain brain cancers such as glioblastoma multiforme, Akbari teaches the following average particle sizes wherein the particle size is, in part, dependent on the relative amount of PLGA polymer coating (Fig. 39; pg 13, [0152]).
For claim 6, Akbari teaches the microparticles may contain PLGA and chitosan ([0003]; pg 14, claim 3).
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Akbari does not teach the limitation of a further coating comprising a first ionic or zwitterionic additive.
Matson teaches the missing element of Akbari.
For claims 7-10, Matson teaches a formulation comprising encapsulated drug particles (pg 1, [0012]). The encapsulated drug particles are useful as time-released drugs that are delivered from the surface of the medical balloon to a target location within the patient, which forms a time-released, drug-eluting deposit of material at the target location (pg 1, [0013]). Matson teaches the particles are coated with a layer comprising polylactoglycolic acid (PLGA) (pg 2, [0023]). Matson teaches the drug may be sirolimus (pg 2, [0025]) or paclitaxel (pg 10, [0055]).
Madsen teaches the coating particles can include adhesive agents that serve to affix the balloon coating to a receiving surface; the adhesive agents may comprise cationic polyamino acids such as polyarginine, polylysine, or polyethyleneimine (pg 11, [0059]). Madsen also teaches that the cationic polyamino acids may assist in cellular adhesion (pg 2, [0029]; pg 10, [0059]; pg 14, claim 31).
It is further noted that these teachings extend to claim 6, for a formulation comprising a cationic coating.
The skilled artisan would have expected success in adding an additional coating comprising a cationic agent such as polyarginine or polylysine over the PLGA encapsulated therapeutic agent taught by Akbari since Matson teaches that a therapeutic agent encapsulated by PLGA, when further encapsulated by a cationic agent such as polyarginine or polylysine has increased cellular adhesion when delivered, and is expected to have improved activity when delivered to the target site. It is further noted that Matson also teaches the advantage of the encapsulation by a cationic agent such as polyarginine or polylysine improves the adhesion of the drug particles to a delivery device such as a balloon to allow more accurate placement of the therapeutic agent to a body lumen (pg 12, [0064]).
2) Claim 2 is rejected under 35 U.S.C. 103 as being unpatentable over Akbari (cited above), in view of Sun (US 2019/0343840 A1; of record).
The teachings of Akbari are set forth above.
Akbari does not teach the limitation of “wherein the PLGA comprises a first PLGA having a weight ratio of lactic acid to glycolic acid of about 85:15 and a second PLGA having a weight ratio of lactic acid to glycolic acid of about 75:25.”
Sun teaches the missing element of Akbari.
Sun teaches a composition comprising a drug such as risperidone encapsulated by a mixture of two PLGA polymers, wherein the polymers comprise two different ratios of lactide to glycolide (pg 2, [0013], and Examples). Sun teaches a encapsulating coating comprising a mixture of the two polymers provides a sustained release microsphere formulation that does not change after long-term storage (Abstract; pg 5, Embodiments 1-13 teach encapsulation).
Sun teaches (pg 2, [0014]):
molar ratio of lactide to glycolide in the uncapped PLGA with the high intrinsic viscosity is within a range from 65:35 to 90:10…and a molar ratio of lactide to glycolide in the uncapped PLGA with the low intrinsic viscosity is within a range from 50:50 to 75:25
As calculated by the Examiner, the high intrinsic viscosity uncapped PLGA includes a molar ratio of lactide to glycolide of 85:15, or a weight ratio of 88:12, given lactide mw of 72.06 and a glycolide mw of 58.04. Similarly, the uncapped PLGA with the low intrinsic viscosity includes a molar ratio of lactide to glycolide of 75:25, or a weight ratio of 79:21. Given that the term “about” is defined by the applicant as +10% (see pg 21, [0062] of the specification), the teachings of Sun overlap the claimed range.
The person of ordinary skill would have had a reasonable expectation of success in selecting two separate PLGA compositions encapsulating a therapeutic agent comprising a first PLGA having a weight ratio of lactic acid to glycolic acid of about 85:15 and a second PLGA having a weight ratio of lactic acid to glycolic acid of about 75:25, both of which are within the ranges taught by Sun in a sustained release formulation since Akbari teaches PLGA encapsulation as a method for controlling the release of an active agent (pg 1, [0002]), and Sun teaches a specific formulation comprising two PLGA polymers that facilitate the advantageous sustained release of the active agent. The skilled artisan would have been motivated to select Sun's encapsulating composition because the references both teach that it is desirable to control and sustain the release of active agent.
Examiner’s Reply to Attorney Arguments dated 3/2/2026
1. Rejection of claims 1 and 3-6 under 35 U.S.C. § 103 over Akbari.
The applicant argues that since dependent claim 7 was not rejected under the present rejection, presently amended independent claim 1 is patentable over Akbari. The applicant further argues that, since dependent claims 3-6 are dependent on independent claim 1, dependent claims 3-6 are patentable for at least the reasons given herein for patentability of independent claim 1.
The Examiner acknowledges the argument presented, but does not consider it persuasive. The rejection of claim 1, as presently amended, set forth above is considered to properly reject all of the elements claimed in amended claim 1. As such, applicant’s argument is considered moot.
2. Rejection of claim 2 under 35 U.S.C. § 103 over Akbari and Sun.
The applicant argues: “Dependent claim 2 depends from independent claim 1. As such, this dependent claim incorporates all the features of claim 1. Accordingly, dependent claim 2 is patentable for at least the reasons given herein for patentability of independent claim 1.”
The Examiner acknowledges the argument presented, but does not consider it persuasive. The rejection of claim 1, as presently amended, set forth above is considered to properly reject all of the elements claimed in amended claim 1. As such, applicant’s argument is considered moot.
3. Rejection of claims 6-10 under 35 U.S.C. § 103 over Akbari and Matson.
The applicant argues at page 10 of the Applicant’s Remarks dated 3/2/2026 (“Remarks”) that Matson's adhesive agents operate at the macro-level balloon coating, not at the individual microparticle level. The applicant argues that the Office Action's characterization of Matson's teaching is not supported by the reference; that a person of ordinary skill would not have been motivated to combine Akbari and Matson to arrive at the claimed invention; and the combination reflects impermissible hindsight reconstruction, as argued also on page 14 of the Remarks.
The Examiner acknowledges the arguments presented, but does not consider them persuasive. The broadest reasonable interpretation of the term “a first ionic or zwitterionic additive that is coated on a surface of the polymer-encapsulated drug particle” in claim 1 as presently amended, is interpreted by the Examiner as requiring particles with at least some portion of the exterior surface coated with a first ionic or zwitterionic additive. That is, claim 1 does not require the particle surfaces having 100% coverage of the first additive, and a partially coated particle meets the limitations of the claim. As such, the Examiner disagrees with the assertion of the applicant argues that the teaching of Matson fails to meet the limitations of claim 1.
Furthermore, it is noted that Matson teaches an embodiment wherein a drug such as rapamycin is completely encapsulated in a biosorbable polymer matrix such as PLGA ([0063]).
Regarding the allegation that there is no motivation to combine Akbari and Matson, Matson also teaches an advantage of the encapsulation by a cationic agent such as polyarginine or polylysine improves the adhesion of the drug particles to a delivery device such as a balloon to allow more accurate placement of the therapeutic agent to a body lumen.
Regarding the allegation that the Examiner relied on impermissible hindsight in the rejection, MPEP 2145(X)(A) states: “[a]ny judgment on obviousness is in a sense necessarily a reconstruction based on hindsight reasoning, but so long as it takes into account only knowledge which was within the level of ordinary skill in the art at the time the claimed invention was made and does not include knowledge gleaned only from applicant’s disclosure, such a reconstruction is proper." In the instant case, the prior art of each of Akbari and Matson were publicly available prior to the filing of the instant application
The applicant argues “Akbari's system does not present a problem that Matson's adhesive agents would solve,” and that “the technological contexts of the two references are substantially different and would not naturally lead a person of ordinary skill from one to the other. Akbari is directed to hydrogel meshes for localized cancer drug delivery, specifically for glioblastoma multiforme treatment. See, Akbari at Abstract. Matson is directed to electrostatic deposition of coatings on expandable medical balloons for vascular intervention.
The Examiner acknowledges the arguments presented, but does not consider them persuasive. It is initially noted that Akbari teaches a composition comprising encapsulated particles dispersed in a matrix, useful for delivery of therapeutic agents ([0001]; [0072]); the mesh element is utilized in some embodiments ([0005]).
It is further noted that, while Matson teaches a drug-eluting coating for medical conditions, one of ordinary skill would take Matson to include uses other than application to blood vessels since Matson teaches the invention more broadly, stating: “In its simplest form, the present invention includes a system and process for forming composite coatings on expandable medical devices that, upon deployment within a patient or host, transfer time-released, drug-eluting deposits at selected sites within the patient that deliver treatments for various medical conditions.” See pg 1, [0011]).
The applicant also argues: The present application teaches that coating individual polymer-encapsulated drug particles with an ionic or zwitterionic additive modifies the zeta potential of the particles, which affects tissue adhesion and drug transfer characteristics. See, present published application at [0069] and [0076]. The application demonstrates that different ionic and zwitterionic additives produce different zeta potentials when coated on the surface of PLGA-encapsulated drug particles. For example, PLGA microspheres without any ionic additive exhibit a zeta potential of -19.9 mV, while microspheres incorporating or coated with different ionic or zwitterionic additives exhibit zeta potentials ranging from -13.34 mV to +35.26 mV.”
The Examiner acknowledges the arguments presented, but does not consider them persuasive. The zeta potential of the particles is not a claimed element. As set forth in MPEP 2145(VI), “Although the claims are interpreted in light of the specification, limitations from the specification are not read into the claims. In re Van Geuns, 988 F.2d 1181, 26 USPQ2d 1057 (Fed. Cir. 1993) (Claims to a superconducting magnet which generates a "uniform magnetic field" were not limited to the degree of magnetic field uniformity required for Nuclear Magnetic Resonance (NMR) imaging. Although the specification disclosed that the claimed magnet may be used in an NMR apparatus, the claims were not so limited.).”
The applicant argues that dependent claims 6-10 are directly or indirectly dependent on independent claim 1 and are patentable for at least the reasons given herein for patentability of independent claim 1.
The Examiner acknowledges the argument presented, but does not consider it persuasive since it is the position of the Examiner that each and every element of claim 1 is taught by the combination of Akbari and Matson, as discussed above.
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 MICHAEL P COHEN whose telephone number is (571)270-7402. The examiner can normally be reached on M-Th 8:30-5:30; F 9-4.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Sahana S. Kaup, can be reached on (571)272-0580. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/MICHAEL P COHEN/Primary Examiner, Art Unit 1612
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