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.
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 7/21/2026 has been entered.
Previous Rejections
Applicant’s arguments, filed 6/18/ 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 Rejections and/or objections not reiterated from previous office actions are hereby withdrawn.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.
Claim Status
Claim 7 is cancelled.
Claim 21 is newly added.
Claims 1-6 and 8-21 are pending.
Claims 11-20 are withdrawn.
Claims 1-6, 8-10, and 21 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 1-6 and 8-10 are rejected under 35 U.S.C. 103 as being unpatentable over Saddiq (US 10,251,842), in view of Matson (US 2015/0024116 A1, of record).
Saddiq teaches nanocapsular cancer treatments comprising natural products encapsulated by a biocompatible polymer consisting of a polylactic-co-glycolic acid) (PLGA) (Abstract, col 2: 12-16). Saddiq teaches the anticancer agent may also be encapsulated within the nanocapsule (col 23: 18-20).
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, for example, paclitaxel (col 16: 35), is a crystalline solid (mp 213-217 oC with decomposition).
Regarding the newly added claim 1 limitation of the zeta potential of the polymer-encapsulated drug particle, Saddiq teaches: “The nanocapsule may have a positive zeta potential in a range of +5 to +30 mV, +10 to +20 mV, or +15 to +20 mV…. For example, a nanocapsule with a biocompatible polymer comprising chitosan may have a positive zeta potential as chitosan has a large positive zeta potential” (col 12: 19-20 and 26-28), within the claimed range. Because the claimed range overlaps with, or is within, the range disclosed by the prior art, a prima facie case of obviousness exists.
Saddiq teaches the PLGA polymer may comprise “a weight ratio of polylactic acid to polyglycolic acid may be in a range of 65:35 to 75:25, 67:33 to 73:27, or 69:31 to 71:29” (col 13: 32-42).
For claims 3 and 4, Saddiq teaches the anticancer drugs doxorubicin, paclitaxel, and docetaxel (16: 34-35).
For claim 5, Saddiq teaches an average diameter of the nanocapsule is in a range of 100-500 nm (0.1 to 0.5 microns; col 2: 1-3), overlapping the claimed range.
For claim 6, Saddiq teaches nanocapsules comprising chitosan may have a positive zeta potential (col 12: 26-28).
Saddiq does not teach the limitation of a further coating comprising a first ionic or zwitterionic additive.
Matson teaches the missing element of Saddiq.
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 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 Saddiq 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 Saddiq (cited above), in view of Matson (cited above) and Sun (US 2019/0343840 A1; of record).
The teachings of Saddiq and Matson are set forth above. As detailed above, Saddiq teaches the PLGA polymer may comprise “a weight ratio of polylactic acid to polyglycolic acid may be in a range of 65:35 to 75:25, 67:33 to 73:27, or 69:31 to 71:29.” However, Saddiq does not teach multiple PLGA polymers such that “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 the combination of Saddiq and Matson.
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 an 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 Saddiq teaches PLGA encapsulation as a method for controlling the release of an active agent (col 13: 28-31), 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.
3) Claim 21 is rejected under 35 U.S.C. 103 as being unpatentable over Saddiq (cited above), in view of Matson (cited above) and Allen (US 2006/0177495 A1).
The teachings of Saddiq and Matson are set forth above.
The combination of Saddiq and Matson does not teach the first ionic or zwitterionic additive comprising a phosphatidylcholine.
Allen teaches the missing element of the combination of Saddiq and Matson.
Allen teaches a composition comprising nanoparticles which are composed of: (a) a biodegradable hydrophobic polymer forming a core, and; (b) an outer amphiphilic layer surrounding the polymer core containing a stabilizing lipid. These nanoparticles are suitable for delivering active agents including paclitaxel and docetaxel (Abstract; pg 4, [0067]). Allen teaches the stabilizing lipids include “include various phosphatidyl choline molecules” (pg 4, [0053]). Allen also teaches the nanoparticles have an average diameter of 50-300 nm, within the claimed range and the range taught by Saddiq.
The stability taught by Allen is measured by assessing the particles in an aqueous media for changes in particle size and precipitation of the particle; that is, “when a noticeable change in the solution occurred where the appearance had gone from having an iridescent/white homogeneous color to being clear with visible aggregates accumulated at the bottom of the dialysis bag or vial” (pg 7, [0101]).
The person of ordinary skill would have had a reasonable expectation of success in selecting a coating comprising phosphatidylcholine to coat the nanoparticle of the combination of Saddiq and Matson since Allen teaches that coatings comprising phosphatidylcholine act to stabilize nanoparticles comprising drugs taught by Saddiq, including paclitaxel and docetaxel, reducing decomposition of the nanoparticles and controlling the release characteristics of the anti-cancer pharmaceutical agent.
Examiner’s Reply to Attorney Arguments dated 6/18/2026
1. Rejection of claims 1 and 3-10 under 35 U.S.C. § 103 over Akbari and Matson
The applicant argues the cited references do not describe or suggest a polymer-encapsulated drug particle including a first ionic or zwitterionic additive that is coated thereon having a positive zeta potential of at least +5 mV as recited in claim 1, as presently amended, and such a property is not inherent in the combination of Akbari and Matson.
Applicant' s arguments have been considered but are moot because the new ground of rejection relies on the prior art of Saddiq. As detailed above, Saddiq clearly teaches a nanoparticle comprising a polymer encapsulating the therapeutic agent comprising chitosan, a cationic additive that imparts a positive zeta potential on the nanoparticle of at least +5 mV.
2. Rejection of claim 2 under 35 U.S.C. § 103 over Akbari and Sun.
The applicant argues that the addition of Sun to Akbari does not cure the missing element of Akbari, namely the newly added limitation of a polymer-encapsulated drug particle including a first ionic or zwitterionic additive that is coated thereon having a positive zeta potential of at least +5 mV as recited in claim 1, as presently amended.
Applicant' s arguments have been considered but are moot because the new ground of rejection relies on the prior art of Saddiq. As detailed above, Saddiq clearly teaches a nanoparticle comprising a polymer encapsulating the therapeutic agent comprising chitosan, a cationic additive that imparts a positive zeta potential on the nanoparticle of at least +5 mV.
CONCLUSION
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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