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.
Election/Restrictions
Applicant’s election of Group I, claims 1-11 and 18-20, in the response dated 2/26/2026, is acknowledged. Because applicant did not distinctly and specifically point out the supposed errors in the restriction requirement, the election has been treated as an election without traverse (MPEP § 818.03(a)).
Claims 12-17 are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to nonelected groups, there being no allowable generic or linking claim.
Claim Status
Claims 18-20 are newly added.
Claims 1-20 are pending.
Claims 12-17 are withdrawn.
Claims 1-11 and 18-20 are examined on the merits in this prosecution.
CLAIM REJECTIONS
Indefiniteness Rejection
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.
Claims 1-11 and 18-20 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 pre-AIA the applicant regards as the invention.
Claim 1 recites the phrase "preferably" in the 15th line. This term renders the claim indefinite because it is unclear whether the limitation(s) following the phrase are part of the claimed invention. See MPEP § 2173.05(d).
Obviousness Rejections
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, 8-11, and 18-20 are rejected under 35 U.S.C. 103 as being unpatentable over Guo (“Radiolabeling of folic acid-modified chitosan with 99mTc as potential agents for folate-receptor mediated targeting,” Bioorganic & Medicinal Chemistry Letters, 2012, Volume 21, Issue 21, 6446-6450), in view of Borbely (US 2013/0302255 A1).
For claim 1, Guo discloses a statistical polysaccharide with a weight-average molecular weight of 6 kDa of formula I (pg 6447, Scheme 1):
PNG
media_image1.png
309
392
media_image1.png
Greyscale
wherein, Rc represents a chelating agent comprising pteridine-p-aminobenzoic acid, Z is a hydrocarbon-based chain comprising 3 carbon atoms and comprises O and N heteroatoms; x is 0.297, (MW= 6000 Da; degree of deacetylation = 70%); y is 0.162, (MW= 6000 Da; degree of deacetylation = 70%; folic acid monomer units= 6); the y/x ratio is ~0.55, which is greater than 0.05; and the sum of x + y is ~0.50, which is greater than 0.30. See pg 6447, Scheme 1 and pg 6447, col 1, paragraph 2 and pg 6450, col 2, #23). The polymer taught by Guo also comprises technetium, a d-block element. It is noted that these teachings also read on claims 3 and 5. Because the claimed range overlaps with the range disclosed by the prior art, a prima facie case of obviousness exists.
For claim 6, Guo discloses the polymer CSFADTC (Scheme !, pg 6447), comprising a dithiocarbamate group, capable of chelating a metal, and the substituted folate group which may be complexed with [99mTcN]2+ (see structure below).
PNG
media_image2.png
336
430
media_image2.png
Greyscale
It is noted that the variables recited in claim 6 overlap those for claim 1 and are discussed above.
For claims 18 and 19, the copolysaccharide B comprises nitrogen in the chain (see Scheme 1).
Guo does not disclose the statistical polysaccharide has a weight-average molecular weight of between 100 kDa and 1000 kDa.
Borbely discloses a polysaccharide, chitosan, having a weight-average molecular weight of between 20 kDa and 600 kDa (pg 4, [0049]-[0056], overlapping the claimed range.
For claims 8-10 and 20, Borbely discloses the polysaccharide is formulated in as a hydrogel (pgs 8-9, [0120]-[0123]). One of ordinary skill in the art is able to partially dry a gel to obtain the xerogels recited in claim 10 and 11.
For claim 2, since the composition taught by the combination of Guo and Borbely reads on the claimed mixture of chitosan A and copolysaccharide B, the composition must have the same physical properties, including degree of crystallinity. Something which is old (e.g. the composition of composition taught by the combination of Guo and Borbely) does not become patentable upon the discovery of a new property (e.g. the degree of crystallinity), and this feature need not have been recognized at the time of the invention. See MPEP 2112(I & II). Put another way, "When the claimed compositions are not novel they are not rendered patentable by recitation of properties, whether or not these properties are shown or suggested in the prior art." In re Spada, 911 F .2d 705, 709, (Fed. Cir. 1990).
Further regarding the limitation of the crystallite size of chitosan A of less than 20 nm in claim 2, one of ordinary skill in the art is able to determine the optimal size desired for a targeting agent and one of ordinary skill would have the knowledge required to obtain the desired size, for example by grinding and sieving the chitosan.
It would be obvious to one of ordinary skill in the art to modify the polysaccharide disclosed by Guo so that the polysaccharide has a weight-average molecular weight of between 20 kDa and 600 kDa and have a reasonable expectation of success, based on the teachings of Borbely; Guo teaches a chitosan substituted as in chitosan B, and Borbely discloses a substituted chitosan having a weight-average molecular weight of between 20 kDa and 600 kDa, comprising a chelating group. Therefore, it is reasonable to expect the polysaccharide disclosed by Guo may be modified so that the polysaccharide has a weight-average molecular weight within the claimed range. One would have been motivated to do so because the selection of a known material based on its suitability for its intended use is prima facie obvious.
2) Claim 7 is rejected under 35 U.S.C. 103 as being unpatentable over Guo (cited above), in view of Borbely (cited above) and Garg (“Current Advances in Chitosan Nanoparticles Based Drug Delivery and Targeting,” Adv Pharm Bull, 2019, 9(2), 195-204).
The teachings of Guo and Borbely are discussed above. Of note is that both Guo (pg 6446, right column) and Borbely (pg 5, (0085) teach the composition is useful for tumor imaging, and Borbely teaches folic acid in the chitosan polymer “selectively link to the folate receptors held on the surface of targeted tumor cells.”
The combination of Guo and Borbely does not teach the addition of a pharmaceutical ingredient to the composition of claim 1.
Garg teaches the missing element of the combination of Guo and Borbely.
Garg teaches chitosan nanoparticles are useful for targeted and controlled release drug delivery systems for delivery of cancer therapy drugs (Abstract; pg 197, “Applications of chitosan nanoparticle”).
The skilled artisan would have expected success in adding Garg's anticancer agent to the composition taught by the combination of Guo and Borbely since the composition of Guo and Borbely is taught as useful for targeting a cancer tumor and Garg teaches chitosan, an element of the composition of Guo and Borbely, is useful for carrying and delivering an anticancer agent. The person of ordinary skill in the art would have found it obvious to add an anticancer agent coordinated to chitosan because ordinarily skilled artisans would have predicted that the anticancer agent would have increased efficacy since it is directed to the same compartment as the tumor by the targeting moiety.
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) 272-6897. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/MICHAEL P COHEN/Primary Examiner, Art Unit 1612
Prosecution Insights