Prosecution Insights
Last updated: April 19, 2026
Application No. 18/548,784

(S)-3-AMINO-4,4-DIHALOCYCLOPENT-1-ENECARBOXYLIC ACID AS SELECTIVE INACTIVATORS OF HUMAN ORNITHINE AMINOTRANSFERASE

Non-Final OA §103§112§DP
Filed
Sep 01, 2023
Examiner
CHICKS, ASHLI ARIANA
Art Unit
1626
Tech Center
1600 — Biotechnology & Organic Chemistry
Assignee
Northwestern University
OA Round
1 (Non-Final)
65%
Grant Probability
Favorable
1-2
OA Rounds
3y 3m
To Grant
99%
With Interview

Examiner Intelligence

Grants 65% — above average
65%
Career Allow Rate
49 granted / 75 resolved
+5.3% vs TC avg
Strong +44% interview lift
Without
With
+43.9%
Interview Lift
resolved cases with interview
Typical timeline
3y 3m
Avg Prosecution
37 currently pending
Career history
112
Total Applications
across all art units

Statute-Specific Performance

§101
2.1%
-37.9% vs TC avg
§103
29.9%
-10.1% vs TC avg
§102
20.4%
-19.6% vs TC avg
§112
23.6%
-16.4% vs TC avg
Black line = Tech Center average estimate • Based on career data from 75 resolved cases

Office Action

§103 §112 §DP
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 . Claim Status Claims 1-21 are pending. Claims 1-21 are rejected. Claim Rejections - 35 USC § 112(b) 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 1-10 and 15-21 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. Regarding claim 1, the phrase "such as" renders the claim indefinite because it is unclear whether the limitations following the phrase are part of the claimed invention. See MPEP § 2173.05(d). Claims 2-10 and 15-21 are rejected for failing to obviate the indefiniteness of claim 1. Claim Rejections - 35 USC § 103 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. Claim(s) 1-3, 5-8 and 13-21 are rejected under 35 U.S.C. 103 as being unpatentable over US 2019/0315677 A1 by Silverman in view of Zhu et al. J. Am. Chem. Soc. 2020, 142, 10, 4892–4903. (cited in the IDS filed 07/02/2025). Determining the scope and contents of the prior art. (See MPEP § 2141.01) The prior art teaches cyclopentene compounds for use as inhibitors of gamma-aminobutyric acid (GABA) aminotransferase (AT) and/or ornithine aminotransferase (OAT) (abstract). The following compound is analogous to a compound of the instant claims where R1 is fluorine and a double bond exists between the α and ε carbons (paragraph [0090]): PNG media_image1.png 154 178 media_image1.png Greyscale . Regarding instant claims 6-7 and 14, the prior art teaches that the compound may be an ammonium salt having a counter ion that is the conjugate base of a protic acid (paragraph [0091]). Regarding instant claims 8 and 15, the prior art discloses a pharmaceutical composition comprising the prior art compound and a pharmaceutically acceptable carrier (paragraph [0092]). Regarding instant claims 16-17, the prior art discloses methods of treating a subject having a disease associated with OAT activity wherein the subject is administered an amount of the compound sufficient to modulate/reduce OAT activity (paragraph [0097]). Silverman lists hepatocellular carcinoma as a cancer for treatment in accordance with instant claims 18-19 and 21 (paragraph [0097]). Ascertainment of the differences between the prior art and the claims. (See MPEP § 2141.02) The prior art teaches 3-carbon substituted 4-aminocyclopent-l-ene-1-carboxylic acid compounds capable of modulating OAT activity but does not disclose compounds with two halogen substituents as required by the instant claims. Finding of prima facie obviousness --- rationale and motivation (See MPEP § 2142-2143) Zhu et al. report (title) “A Remarkable Difference That One Fluorine Atom Confers on the Mechanisms of Inactivation of Human Ornithine Aminotransferase by Two Cyclohexene Analogues of γ-Aminobutyric Acid”. In the prior art Zhu et al. prepared the following GABA analogs wherein compound 8 has a single fluorine substituent like the compound of Silverman and compound 9 is difluoro-substituted as required by the instant claims (abstract): PNG media_image2.png 342 282 media_image2.png Greyscale . Zhu et al. conclude, “[w]hile monofluoro substituted analogue 8 inactivates hOAT via an enamine pathway (Scheme 2, pathway a), difluoro analogue 9 inactivates hOAT via a novel addition-aromatization mechanism (Scheme 2, pathway c), contributing to its significantly enhanced potency” (page 4901). Accordingly, a person of ordinary skill seeking to prepare OAT inhibitors with improved potency would be motivated by the teachings of Zhu et al. to modify the compound of Silverman to be difluoro-substituted as recited in instant claims 1-3, 5 and 13. The resulting compound is represented below: PNG media_image3.png 202 268 media_image3.png Greyscale . Regarding instant claim 20, Zhu et al. report that specific knockdown of hOAT was found to suppress the growth on nonsmall cell lung cancer in vitro and in vivo (page 4893). Accordingly, a person of ordinary skill seeking to treat hOAT related cancers would be motivated to administer the prior art compound to improve therapeutic outcomes. Closest Prior Art Regarding instant claims 9-12, the closest prior art appears to be the combined teachings of WO 2016/073983 A2 by Silverman et al. and Shen et al. ACS Medicinal Chemistry Letters 2020 11 (10), 1949-1955. (cited in the IDS filed 07/02/2025). Silverman et al. discuss compounds for use in OAT inhibition or inactivation (paragraph [0013]) and disclose the following genus: PNG media_image4.png 354 954 media_image4.png Greyscale Compound 22 is analogous to a compound of the instant claims but differs by the absence of a double bond between the α and β or α and ε carbon (Figure 3): PNG media_image5.png 222 354 media_image5.png Greyscale . Shen et al. discuss (title) “Mechanism-Based Design of 3-Amino-4-Halocyclopentenecarboxylic Acids as Inactivators of GABA Aminotransferase” and report that modifying FCP to include a double bond between the α and β carbon resulted in “a 2-fold greater binding affinity with reduced transition state energy for the rate-determining deprotonation step, which is responsible for a 12-fold enhancement in the rate constant, making 6a 25-fold more efficient as an inactivator of GABA-AT than FCP” (page 1953). However, when the compounds were tested for selectivity over ornithine aminotransferase 6a had 10-fold weaker binding affinity relative to its effect with GABA-AT (page 1953). Accordingly, a person of ordinary skill seeking to prepare compounds with improved properties for OAT inhibition would not have been motivated by the teachings of Shen et al. to modify the compound of Silverman et al. to include a double bond between the α and β carbon because this modification may result in a decrease in binding affinity for ornithine aminotransferase. Double Patenting The nonstatutory double patenting rejection is based on a judicially created doctrine grounded in public policy (a policy reflected in the statute) so as to prevent the unjustified or improper timewise extension of the “right to exclude” granted by a patent and to prevent possible harassment by multiple assignees. A nonstatutory double patenting rejection is appropriate where the conflicting claims are not identical, but at least one examined application claim is not patentably distinct from the reference claim(s) because the examined application claim is either anticipated by, or would have been obvious over, the reference claim(s). See, e.g., In re Berg, 140 F.3d 1428, 46 USPQ2d 1226 (Fed. Cir. 1998); In re Goodman, 11 F.3d 1046, 29 USPQ2d 2010 (Fed. Cir. 1993); In re Longi, 759 F.2d 887, 225 USPQ 645 (Fed. Cir. 1985); In re Van Ornum, 686 F.2d 937, 214 USPQ 761 (CCPA 1982); In re Vogel, 422 F.2d 438, 164 USPQ 619 (CCPA 1970); In re Thorington, 418 F.2d 528, 163 USPQ 644 (CCPA 1969). A timely filed terminal disclaimer in compliance with 37 CFR 1.321(c) or 1.321(d) may be used to overcome an actual or provisional rejection based on nonstatutory double patenting provided the reference application or patent either is shown to be commonly owned with the examined application, or claims an invention made as a result of activities undertaken within the scope of a joint research agreement. See MPEP § 717.02 for applications subject to examination under the first inventor to file provisions of the AIA as explained in MPEP § 2159. See MPEP § 2146 et seq. for applications not subject to examination under the first inventor to file provisions of the AIA . A terminal disclaimer must be signed in compliance with 37 CFR 1.321(b). The filing of a terminal disclaimer by itself is not a complete reply to a nonstatutory double patenting (NSDP) rejection. A complete reply requires that the terminal disclaimer be accompanied by a reply requesting reconsideration of the prior Office action. Even where the NSDP rejection is provisional the reply must be complete. See MPEP § 804, subsection I.B.1. For a reply to a non-final Office action, see 37 CFR 1.111(a). For a reply to final Office action, see 37 CFR 1.113(c). A request for reconsideration while not provided for in 37 CFR 1.113(c) may be filed after final for consideration. See MPEP §§ 706.07(e) and 714.13. The USPTO Internet website contains terminal disclaimer forms which may be used. Please visit www.uspto.gov/patent/patents-forms. The actual filing date of the application in which the form is filed determines what form (e.g., PTO/SB/25, PTO/SB/26, PTO/AIA /25, or PTO/AIA /26) should be used. A web-based eTerminal Disclaimer may be filled out completely online using web-screens. An eTerminal Disclaimer that meets all requirements is auto-processed and approved immediately upon submission. For more information about eTerminal Disclaimers, refer to www.uspto.gov/patents/apply/applying-online/eterminal-disclaimer. Claims 1-3, 5-8 and 13-21 are rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1-17 of U.S. Patent No. 10822301 in view of Zhu et al. J. Am. Chem. Soc. 2020, 142, 10, 4892–4903. Claim 14 of the patent discloses the following compound which serves as the basis of a rejection under 35 USC 103 (Col. 23): PNG media_image1.png 154 178 media_image1.png Greyscale . The teachings and rationale of Silverman and Zhu et al. relative to instant claims 1-3, 5-8 and 13-21 are incorporated here by reference. The instant claims are deemed to be variants of the subject matter of the patent for the same reasons as under 35 USC 103. Claims 1-2, 4-12 and 15-21 are rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1-28 of U.S. Patent No. 11993569 in view of Zhu et al. J. Am. Chem. Soc. 2020, 142, 10, 4892–4903. Claims 1 and 6 of the patent disclose a zwitterion form of the following compound (Col. 45-46): PNG media_image6.png 148 272 media_image6.png Greyscale . The compound is analogous to a compound of the instant claims where R1 is fluorine and a double bond exists between the α and β carbons. Zhu et al. report (title) “A Remarkable Difference That One Fluorine Atom Confers on the Mechanisms of Inactivation of Human Ornithine Aminotransferase by Two Cyclohexene Analogues of γ-Aminobutyric Acid”. In the prior art Zhu et al. prepared the following GABA analogs wherein compound 8 has a single fluorine substituent like the compound of patent and compound 9 is difluoro-substituted as required by the instant claims (abstract): PNG media_image2.png 342 282 media_image2.png Greyscale . Zhu et al. conclude, “[w]hile monofluoro substituted analogue 8 inactivates hOAT via an enamine pathway (Scheme 2, pathway a), difluoro analogue 9 inactivates hOAT via a novel addition-aromatization mechanism (Scheme 2, pathway c), contributing to its significantly enhanced potency” (page 4901). Accordingly, a person of ordinary skill seeking to prepare OAT inhibitors with improved potency would be motivated by the teachings of Zhu et al. to modify the patent compound to be difluoro-substituted as recited in instant claims 1-2, 4-5, 9 and 11. The resulting compound is represented below: PNG media_image7.png 198 274 media_image7.png Greyscale . Regarding instant claims 6-7, 10 and 12, claim 7 of the patent teaches that the compound may be in salt form having a counter ion that is the conjugate base of a protic acid (Col. 46). Regarding instant claims 8 and 15, claim 8 of the patent discloses a pharmaceutical composition comprising the patent compound and a pharmaceutically acceptable carrier (Col. 46). Regarding instant claims 16-17, claims 25-28 of the patent disclose methods of treating a subject having a disease associated with OAT activity wherein the subject is administered an amount of the compound sufficient to modulate/reduce OAT activity (Col. 48). Claim 28 recites hepatocellular carcinoma and non-small cell lung cancer cancers for treatment in accordance with instant claims 18-21 (Col. 48). Conclusion Any inquiry concerning this communication or earlier communications from the examiner should be directed to ASHLI A CHICKS whose telephone number is (571)270-0582. The examiner can normally be reached M-Th 7 a.m.- 5 p.m.. Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice. If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, James H Alstrum-Acevedo can be reached at (571)272-5548. 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. /A.A.C./Examiner, Art Unit 1626 /MATTHEW P COUGHLIN/Primary Examiner, Art Unit 1626
Read full office action

Prosecution Timeline

Sep 01, 2023
Application Filed
Mar 06, 2026
Non-Final Rejection — §103, §112, §DP (current)

Precedent Cases

Applications granted by this same examiner with similar technology

Patent 12589107
COMPOSITION CONTAINING NICOTINAMIDE MONONUCLEOTIDE AND MOGROSIDE, AND APPLICATION THEREOF
2y 5m to grant Granted Mar 31, 2026
Patent 12590088
JAK INHIBITOR COMPOUND AND PHARMACEUTICAL COMPOSITION INCLUDING THE SAME
2y 5m to grant Granted Mar 31, 2026
Patent 12564552
ORAL PRODUCT WITH A BASIC AMINE AND AN ION PAIRING AGENT
2y 5m to grant Granted Mar 03, 2026
Patent 12552801
NEW INDAZOLE DERIVATIVES
2y 5m to grant Granted Feb 17, 2026
Patent 12540130
SUBSTITUTED PYRROLIDINE AMIDES IV
2y 5m to grant Granted Feb 03, 2026
Study what changed to get past this examiner. Based on 5 most recent grants.

AI Strategy Recommendation

Get an AI-powered prosecution strategy using examiner precedents, rejection analysis, and claim mapping.
Powered by AI — typically takes 5-10 seconds

Prosecution Projections

1-2
Expected OA Rounds
65%
Grant Probability
99%
With Interview (+43.9%)
3y 3m
Median Time to Grant
Low
PTA Risk
Based on 75 resolved cases by this examiner. Grant probability derived from career allow rate.

Sign in with your work email

Enter your email to receive a magic link. No password needed.

Personal email addresses (Gmail, Yahoo, etc.) are not accepted.

Free tier: 3 strategy analyses per month