Prosecution Insights
Last updated: May 04, 2026
Application No. 18/259,438

COMPOSITIONS AND ASSOCIATED METHODS FOR SUSTAINED-RELEASE OF RADIOACTIVE AGENTS AND THEIR APPLICATIONS

Non-Final OA §102§112
Filed
Jun 27, 2023
Priority
Dec 29, 2020 — provisional 63/131,760 +1 more
Examiner
DICKINSON, PAUL W
Art Unit
1618
Tech Center
1600 — Biotechnology & Organic Chemistry
Assignee
Suzhou Xinxin Biopharma Co. Ltd.
OA Round
1 (Non-Final)
63%
Grant Probability
Moderate
1-2
OA Rounds
5m
Est. Remaining
72%
With Interview

Examiner Intelligence

Grants 63% of resolved cases
63%
Career Allowance Rate
648 granted / 1028 resolved
+3.0% vs TC avg
Moderate +10% lift
Without
With
+9.5%
Interview Lift
resolved cases with interview
Typical timeline
3y 3m
Avg Prosecution
43 currently pending
Career history
1071
Total Applications
across all art units

Statute-Specific Performance

§101
0.6%
-39.4% vs TC avg
§103
42.1%
+2.1% vs TC avg
§102
19.9%
-20.1% vs TC avg
§112
25.1%
-14.9% vs TC avg
Black line = Tech Center average estimate • Based on career data from 1028 resolved cases

Office Action

§102 §112
CTNF 18/259,438 CTNF 84045 Notice of Pre-AIA or AIA Status 07-03-aia AIA 15-10-aia The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA. Election/Restrictions 08-25 AIA Applicant's election with traverse of Group I in the reply filed on 3/2/2026 is acknowledged. The traversal is on the ground(s) that there would be no undue search burden to examine the groups together . This is not found persuasive because search burden is not a criterion for restriction under 35 USC 121 and 372. The standard for restriction is lack of unity of invention. The groups lack unity of invention for the reasons set forth in the restriction requirement . The requirement is still deemed proper and is therefore made FINAL. Claim Rejections - 35 USC § 112 07-30-02 AIA 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. The following is a quotation of 35 U.S.C. 112 (pre-AIA), second paragraph: The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention. Claims 1-14 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 applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention. In claim 1, the grammar and punctuation of the claim makes it unclear if “cationic biopolymer-based” qualifies “nanoparticle (NP)” only, or also qualifies “microspheres (MP).” Further, it’s unclear what it means for a nanoparticle and microsphere to be “cationic biopolymer-based.” This is not a term of art, and the artisan would not know what attribute or property the claimed nanoparticles or microspheres need to have to be considered “based” on a cationic biopolymer. Further regarding claims 4 and 8-9 , it’s unclear why the recitation “(e.g. … )” is in parentheses and whether or not the recitation following “e.g.” are positive claim limitations or are merely exemplary. Further regarding claim 10, it’s unclear how high the claimed cytotoxicity needs to be to be considered to possess “high cytotoxicity.” The term “high cytotoxicity” in is a relative term which renders the claim indefinite. The term is not defined by the claim, the specification does not provide a standard for ascertaining the requisite degree, and one of ordinary skill in the art would not be reasonably apprised of the scope of the invention. Claim Rejections - 35 USC § 102 07-06 AIA 15-10-15 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 (i.e., changing from AIA to pre-AIA) 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. 07-07 AIA 07-07-aia The following is a quotation of the appropriate paragraph of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action: A person shall be entitled to a patent unless – 07-08-aia AIA (a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention. 07-12-aia AIA (a)(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention. 07-15 AIA Claim s 1-14 are rejected under 35 U.S.C. 102 ( a)(1) and (a)(2 ) as being anticipated by US 2020/0197541 to Nanovi (IDS filed 9/25/2023). Nanovi teaches a radiotherapeutic hydrogel, comprising a) a biopolymer hydrogel, b) an anionic radioactive agent; and c) a cationic biopolymer or cationic biopolymer containing nanoparticles (biopolymer-based nanoparticles), wherein the cationic biopolymer or cationic biopolymer associate with the anionic radioactive agent and are dispersed in the hydrogel (abstract; paragraphs 1, 16-17, 20, 24; claims), which provide improved formulations for guiding radiotherapy; paragraph17, after injection, the formulation provides a well-defined assembly of x-ray contrast agents which may serve as a marker, thus enabling tracking of tumor movement during radiotherapy; (paragraph 16), the hydrogel, gel forming compositions may be loaded with x-ray agents such as iodinated polymers and nanoparticles prior to or during gel formation, by diffusion into the hydrogel composition, these x-ray particles may be entrapped in the gel matrix), comprising: a) a biopolymer hydrogel (paragraph16), the hydrogel, gel forming compositions may be loaded with x-ray agents such as iodinated polymers and nanoparticles prior to or during gel formation, by diffusion into the hydrogel composition; paragraph20, a gel is defined as a carrier matrix in which the contrast agent is dispersed and/or dissolved within, which includes systems such as hydrogels); b) an anionic radioactive agent (paragraph16, the hydrogel, gel forming compositions may be loaded with x-ray agents such as iodinated polymers and nanoparticles prior to or during gel formation, by diffusion into the hydrogel composition, these x-ray particles may be entrapped in the gel matrix; paragraph24, X-ray contrast agents selected from lodine (1): paragraph26, the gel-forming composition comprise radioactive compounds; paragraph28, radioactive compounds may comprise isotopes of Astatine (211 At). lodine and Astatine-211 are examples of the anionic radioactive agent; see instant claim 9, wherein the anionic radioactive agent is selected from anionic radioisotopes (e.g.,Astatine-22, lodine-125, or lodine-131)); and c) a cationic biopolymer or a cationic biopolymer-based nanoparticles (NP) or microspheres (MS) (paragraph16, the hydrogel, gel forming compositions may be loaded with x-ray agents including iodinated polymers and nanoparticles prior to or during gel formation , by diffusion into the hydrogel composition. these x-ray particles may be entrapped in the gel matrix; paragraph65-66, gel-forming system undergoes gelation, the polymers in the former system include chitosan (a cationic biopolymer). Regarding the recitation in claim 10, “wherein the anionic radioactive agent possesses high cytotoxicity and/or selectivity to proliferating tumor cells,” a composition cannot be separated from its properties. As the radioactive agent of Nanovi is structurally identical to the present radioactive agent, it must possess the same properties, that is, possess high cyctotoxcity and/or selectivity to proliferating tumor cells. Regarding the recitations “wherein the radiotherapeutic hydrogel is used for selective internal radiation therapy (SIRT) via an intratumor administration” (claim 11), “wherein the intratumor administration comprises imaging-guided percutaneous and/or intraoperative injection (claim 12), “is used for selective internal radiation therapy” (claim 13), and “wherein the intracavity administration comprises….” (Claim 14) are intended uses of the claimed radiotherapeutic hydrogel . Conclusion Any inquiry concerning this communication or earlier communications from the examiner should be directed to PAUL W DICKINSON whose telephone number is (571)270-3499. The examiner can normally be reached on M-F 9 AM to 7:30 PM. If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Michael Hartley can be reached on 571-272-0616. The fax phone number for the organization where this application or proceeding is assigned is 571-273-83. Information regarding the status of an application may be obtained from the Patent Application Information Retrieval (PAIR) system. Status information for published applications may be obtained from either Private PAIR or Public PAIR. Status information for unpublished applications is available through Private PAIR only. For more information about the PAIR system, see http://pair-direct.uspto.gov. Should you have questions on access to the Private PAIR system, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative or access to the automated information system, call 8-786-9199 (IN USA OR CANADA) or 571-272-10. /PAUL W DICKINSON/Primary Examiner, Art Unit 1618 March 30, 2026 Application/Control Number: 18/259,438 Page 2 Art Unit: 1618 Application/Control Number: 18/259,438 Page 3 Art Unit: 1618 Application/Control Number: 18/259,438 Page 4 Art Unit: 1618 Application/Control Number: 18/259,438 Page 5 Art Unit: 1618 Application/Control Number: 18/259,438 Page 6 Art Unit: 1618
Read full office action

Prosecution Timeline

Jun 27, 2023
Application Filed
Apr 01, 2026
Non-Final Rejection — §102, §112 (current)

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Study what changed to get past this examiner. Based on 5 most recent grants.

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Prosecution Projections

1-2
Expected OA Rounds
63%
Grant Probability
72%
With Interview (+9.5%)
3y 3m (~5m remaining)
Median Time to Grant
Low
PTA Risk
Based on 1028 resolved cases by this examiner. Grant probability derived from career allowance rate.

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