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 .
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 January 9, 2026 has been entered.
In that response, claims 258 and 276 were amended. Claims 258, 261-269, and 276-277 are treated on the merits in this action. 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 Rejections - 35 USC § 112
The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
The following is a quotation of the first paragraph of pre-AIA 35 U.S.C. 112:
The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention.
Claims 258, 261-269, and 276-277 are rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the written description requirement. The claim(s) contains subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for applications subject to pre-AIA 35 U.S.C. 112, the inventor(s), at the time the application was filed, had possession of the claimed invention.
The methodology for determining adequacy of written description entails (1) for each claim, determining what the claim as a whole covers, (2) reviewing the entire application to understand how applicant provides support for the claimed invention including each element and/or step, and (3) determining whether there is sufficient written description to inform a skilled artisan that applicant was in possession of the claimed invention as a whole at the time the application was filed. MPEP §2163(II). Also the “written description requirement for a claimed genus may be satisfied through sufficient description of a representative number of species by actual reduction to practice …, reduction to drawings …, or by disclosure of relevant, identifying characteristics, i.e., structure or other physical and/or chemical properties, by functional characteristics coupled with a known or disclosed correlation between function and structure, or by a combination of such identifying characteristics, sufficient to show the applicant was in possession of the claimed genus.” MPEP §2163(II)(A)(3)(a)(ii) (citations omitted). The “Federal Circuit has explained that a specification cannot always support expansive claim language and satisfy the requirements of 35 U.S.C. 112 ‘merely by clearly describing one embodiment of the thing claimed’.” Id. (citations omitted).
(1) Claim 258 as a whole covers a method of making crosslinked biodegradable particles having a diameter between 5 and 100 microns, comprising dissolving in a solvent polyester backbones comprising polylactic acid, polyester backbones comprising polyvalerolactone, allyl groups, a multifunctional thiol, and a photoinitiator, emulsifying the solution, and then irradiating the emulsion to react the thiol with allyl groups to form a crosslink, the crosslink being a portion of the resulting particle. Claim 276 is similar, but recites 1,6-hexanedithiol, 2,2-dimehoxy-2-phenylacetohephenone, and tetrahydrofuran, and the polyester backbones comprise polylactic acid and polycaprolactone. The allyl groups need not be part of the polyesters that are dissolved, i.e., any allylic carbon-containing compound is within the scope of claims 258 and 276.
(2) The entire application has been reviewed to understand how applicant provides support for the claimed invention. The disclosure teaches reacting poly- or allylvalerolactone (PAVL) or polyallyl lactide (PAL) (e.g., paras.0129, 0173 pre-grant publication US 20 23/0190664). More generally “any of the valerolactone, caprolactone, lactic acid, lactide, or glycolic acid is functionalized with a functional group… selected from an allyl group,…” (para.0092). The “functional group of the polyester backbone comprises an olefin group (e.g., an allyl group),…” (para.0093). There is no disclosure of reacting any allyl group, i.e., any allyl compound, other than the allyl group as part of the polyester “backbone”.
(3) Therefore it is determined that there is insufficient written description to inform a skilled artisan that applicant was in possession of the claimed invention as a whole at the time the application was filed.
Claim Rejections - 35 USC § 112
The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
The following is a quotation of the first paragraph of pre-AIA 35 U.S.C. 112:
The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention.
Claims 258, 261-269, 276, and 277 are rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, because the specification, while being enabling for preparing crosslinked biodegradable particles, using the method of claims 258 and 276, from polyallylvalerolactone or the polyesters of claim 276 that are allyl-functionalized, it does not reasonably provide enablement for preparing the particles, using the method of claims 258 and 276, from polyester backbones not functionalized with allyl groups.
The specification does not enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to practice the invention commensurate in scope with these claims. Claims 258, 261-269, and 276-277 encompass method of preparing a crosslinked biodegradable particle, comprising dissolving polyester backbones, a multifunctional thiol, and a photoinitiator in at least one solvent to form a solution, emulsifying the solution in an aqueous phase to form an emulsion, irradiating the emulsion with UV light to react the multifunctional thiol with allyl groups to form a crosslink, evaporating at least a portion of the solvent from the emulsion, and isolating the crosslinked biodegradable particles, “wherein the crosslinked biodegradable particle has a diameter of between 5 µm and 100 µm and is configured to release a drug dispersed therein over a period of at least one month in an aqueous environment”. While the Applicant’s disclosure may be enabling for preparing crosslinked biodegradable particles, using the method of claims 258 and 276, from polyallylvalerolactone or the polyesters of claim 276 that are allyl-functionalized, it does not reasonably provide enablement for preparing the particles, using the method of claims 258 and 276, from a polyester backbone not functionalized with allyl groups.
In re Wands, 858 F.2d 731, 736-40, 8 USPQ2d 1400, 1403-07 (Fed. Cir. 1988), set forth eight factors to be considered when determining whether there is sufficient evidence to support a determination that a disclosure does not satisfy the enablement requirement and whether any necessary experimentation is "undue." (MPEP § 2164.01)
a. The breadth of the claim: The rejected claims are drawn to methods of preparing a crosslinked biodegradable particle, comprising dissolving any polyester backbones comprising either polylactic acid, polyvalerolactone, or polycaprolactone, any allyl compound, any multifunctional thiol, and any photoinitiator in at least one of any solvent to form a solution, emulsifying the solution in an aqueous phase to form an emulsion, irradiating the emulsion with UV light to react the multifunctional thiol with two allyl groups to form a crosslink, evaporating at least a portion of the solvent from the emulsion, and isolating the crosslinked biodegradable particles, “wherein the crosslinked biodegradable particle has a diameter of between 5 µm and 100 µm and is configured to release a drug dispersed therein over a period of at least one month in an aqueous environment”. The allyl compound is unlimited in kind with the proviso that they react with the thiol groups to crosslink.
b. Nature of the invention: The nature of the invention is methods of crosslinking a polyester in a thiol-ene reaction with a photoinitiator to from crosslinked biodegradable particles having a diameter between 5 µm and 100 µm “and is configured to release a drug dispersed therein over a period of at least one month in an aqueous environment”.
c. The state of the prior art: Zou (Zou, J., et al., Clicking Well-Defined Biodegradable Nanoparticles and Nanocapsules by UV-Induced Thiol-Ene Cross-Linking in Transparent Miniemulsions, Adv. Mater. 2011, 23, 4274–4277) teaches preparing crosslinked nanoparticles by reacting allyl-functionalized polylactide 2 with 1,4-butanediol bis(3-mercapto-propionate) 4 as the dithiol cross-linker and 2,2-dimethoxy-2-phenylaceto-phenone (DMPA) as the photoinitiator (Scheme 1 and accompanying text; see title; abstract; pp.4274-75, Experimental section pp.4276-77). A transparent miniemulsion was formed using an oil, and water as the continuous phase (p.4274 rt. col.), followed by UV irradiation. The first three steps of claim 258, i.e., dissolving, emulsifying, and irradiating, read on Zou’s method. In Zou however, these steps produced nanoparticles, not microparticles having a diameter within the range in claim 258. Claim 258 further recites the evaporating and the isolating steps; however these are performed after forming the crosslink, and therefore without more it is not seen that those steps in claim 258 would enlarge the particle diameter.
d. Level of one of ordinary skill in the art: the level of ordinary skill is high as trained chemists or technicians would prepare crosslinked biodegradable particles for medical applications, e.g. a drug delivery device.
e. Level of predictability in the art: the level of predictability in reacting a polyester of any structure, any allyl group-comprising compound, and size with any multifunctional thiol, any photoinitiator, in any solvent, under any reaction condition, would be low, to obtain crosslinked particles “wherein the crosslinked biodegradable particle has a diameter of between 5 µm and 100 µm and is configured to release a drug dispersed therein over a period of at least one month in an aqueous environment”. Zou evidences that for allyl-functionalized polylactide, even using the same or similar reagents as in the present claims, and the identical steps, nanoparticles are formed, not microparticles.
f. Amount of direction provided by the inventor: Applicant does not appear to disclose guidance or methods of how to specifically use any polyester other than polyallylvalerolactone or copolymers thereof, including those comprising a polylactic acid and polyvalerolactone, or polycaprolactone that do not comprise allyl groups, to prepare the crosslinked biodegradable particles using the method of claim 258. The specific reaction parameters that attain the microparticles are not recited in the claims, nor disclosed, for the particles formed from polyester backbones comprising polylactic acid and polyvalerolactone, “wherein the crosslinked biodegradable particle has a diameter of between 5 µm and 100 µm and is configured to release a drug dispersed therein over a period of at least one month in an aqueous environment”.
g. Existence of working examples: The disclosure does not include any examples or theoretical models supporting the preparation, using the claimed method, of any crosslinked biodegradable particles having a diameter between 5 and 100 microns that do not involve using polyallylvalerolactone. Therefore the disclosure does not inform whether the same reaction parameters that attain microparticles for polyallylvalerolactone apply to polyester backbones comprising polylactic acid and polyglycolic acid. Moreover the nature of the nature of the configuration for releasing “a drug dispersed therein over a period of at least one month in an aqueous environment” is unlimited in kind. The skilled artisan would understand that achieving sustained release for a drug depends on its solubility in its immediate environment. Here it is the particle within which the drug is dispersed, comprising crosslinked polyesters with polylactide and polyvalerolactone groups.
h. Quantity or experimentation needed to make or use the invention based on the content of the disclosure: considering the state of the art as discussed above, particularly regarding the unpredictability of widely variable reactants to crosslinking, and the lack of guidance provided in the specification, the person of ordinary skill would have to engage in significant amount experimentation and ingenuity to practice the invention commensurate in the scope of the claims.
In conclusion, the specification does not enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to use the invention commensurate in scope with claims 258, 261-269, 276, and 277.
Response to Arguments
Applicant’s arguments with respect to claim(s) 258, 261-269, and 276-277 have been considered but are moot because the new ground of rejection does not rely on any reference applied in the prior rejection of record for any teaching or matter specifically challenged in the argument.
CONCLUSION
No claim is allowed.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to H. S. PARK whose telephone number is (571)270-5258. The examiner can normally be reached on weekdays.
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/H. SARAH PARK/Primary Examiner, Art Unit 1614