Prosecution Insights
Last updated: April 19, 2026
Application No. 18/087,678

METHODS FOR THE PREPARATION OF LINKER PAYLOAD CONSTRUCTS

Non-Final OA §103
Filed
Dec 22, 2022
Examiner
PUTTLITZ, KARL J
Art Unit
1646
Tech Center
1600 — Biotechnology & Organic Chemistry
Assignee
Synaffix B.V.
OA Round
1 (Non-Final)
69%
Grant Probability
Favorable
1-2
OA Rounds
2y 8m
To Grant
87%
With Interview

Examiner Intelligence

Grants 69% — above average
69%
Career Allow Rate
974 granted / 1409 resolved
+9.1% vs TC avg
Strong +18% interview lift
Without
With
+18.2%
Interview Lift
resolved cases with interview
Typical timeline
2y 8m
Avg Prosecution
58 currently pending
Career history
1467
Total Applications
across all art units

Statute-Specific Performance

§101
0.7%
-39.3% vs TC avg
§103
37.5%
-2.5% vs TC avg
§102
11.3%
-28.7% vs TC avg
§112
26.8%
-13.2% vs TC avg
Black line = Tech Center average estimate • Based on career data from 1409 resolved cases

Office Action

§103
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 . Election/Restrictions Applicant’s election without traverse in the reply filed on 1/14/2026 is acknowledged: PNG media_image1.png 290 638 media_image1.png Greyscale PNG media_image2.png 214 590 media_image2.png Greyscale The elected compound may not conform to formula (1) since it does not have payload (D). However, based upon Applicant’s remarks in the reply dated 1/14/2026, claims 1, 4, 6, 8, 13 and 14 cover the elected invention and are therefore treated on the merits, below. Consequently, claims 2, 3, 5, 7, 9-12, 20-22 are withdrawn from consideration as exclusively covering a non-elected invention. 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. Claims 1, 4, 6, 13 and 14 are rejected under 35 U.S.C. 103 as being unpatentable over WO 2019/057964 (WO 964). Claims 1, 4, 6, 13 and 14 an recite an alkyne compound of formula (2) containing an activated ester group (-C(O)-X), which allows it to be reacted with the amino group of a drug moiety of formula D-NHR3 (3). The alkyne moiety allows this molecule to be conjugated to a biomolecule by means of a cycloaddition reaction. In this regard, WO 964 teaches the recited condensation of compounds of formulas (2) and (3). Specifically, see example 43, in particular [00327], [00337]; fig. 6, teaching condensation of dibenzocyclooctyne-N-succinimidyl ester with an amine-containing amanitin precursor, as well as the subsequent conjugation to DUPA-Fc: PNG media_image3.png 830 842 media_image3.png Greyscale WO 964 may not teach activation of the corresponding carboxylic acid, i.e., -COOH of formula (2). However, WO 964 specifically teaches use of the N-succinimidyl ester of the cyclooctyne (i.e., dibenzocyclooctyne-N-succinimidyl ester), and activation of this precursor is sufficiently taught, and prima facie obvious. In this manner, the difference between the process of WO 964 and and the claimed method is that WO 964 may not teach the claimed method with particularity so as to amount to anticipation (See M.P.E.P. § 2131: "[t]he identical invention must be shown in as complete detail as is contained in the ... claim." Richardson v. Suzuki Motor Co., 868 F.2d 1226, 1236, 9 USPQ2d 1913, 1920 (Fed. Cir. 1989). The elements must be arranged as required by the claim, but this is not an ipsissimis verbis test, i.e., identity of terminology is not required. In re Bond, 910 F.2d 831, 15 USPQ2d 1566 (Fed. Cir. 1990).). However, based on the above, WO 964 teaches the elements of the claimed method with sufficient guidance, particularity, and with a reasonable expectation of success, that the invention would be prima facie obvious to one of ordinary skill (the prior art reference teaches or suggests all the claim limitations with a reasonable expectation of success. See M.P.E.P. § 2143). Claim 8 is rejected under 35 U.S.C. 103 as being unpatentable over WO 2019/057964 (WO 964) in view of WO 2017/137456 (WO 456). WO 964 may fail to teach the alkyne compound of formula (2) with the sulfonamide linker (L1) required by claim 8: PNG media_image4.png 114 148 media_image4.png Greyscale However, this linker functionality was well within the purview of those of ordinary skill. It is for this proposition that the rejection joins WO 456. Specifically, WO 456 teaches that this linker is employed in a bioconjugates, such as an anti-body-drug conjugates, and is not therapeutically inert but has an effect on the therapeutic index of the bioconjugate. WO 456 teaches that these linkers increase therapeutic index of bioconjugates for use in treatment, in particular cancer, see abstract. See also, page 4: PNG media_image5.png 520 814 media_image5.png Greyscale In particular, WO 456 teaches that these linkages are used specifically with cyclooctyne linker payloads, such as those of instant formula (1): PNG media_image6.png 314 592 media_image6.png Greyscale In this way, those of ordinary skill could have applied the sulfonamide linker in the manner required and in a predictable fashion for the purposes of obtaining providing the recited alkyne compound of formula (2) comprising these linkages. As outlined above, WO 964 teaches the recited condensation of compounds of formulas (2) and (3) to prepare linker-payload precursors for ADC’s. WO 456 is added for the proposition that alkyne compounds of formula (2), containing sulfonamide linkage in claim 8, are applicable to the process preparing these ADC linker-payload precursors. Specifically, WO 456 teaches the particular known technique of using these linkages in ADC’s to increase therapeutic index was recognized as part of the ordinary capabilities of one skilled in the art. In this regard, those of ordinary skill would have recognized that applying the known technique to preparing linker-payloads would have yielded predictable results. Accordingly, using an alkyne compound of formula (2) with the recited sulfonamide linkages for purposes of providing an ADC precursor would have been prima facie obvious. Conclusion Any inquiry concerning this communication or earlier communications from the examiner should be directed to KARL J PUTTLITZ whose telephone number is (571)272-0645. The examiner can normally be reached on Monday to Friday from 9 a.m. to 5 p.m. If attempts to reach the examiner by telephone are unsuccessful, the examiner's acting supervisor, Gregory Emch, can be reached at telephone number 571-272-8149. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300. 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). /KARL J PUTTLITZ/ Primary Examiner, Art Unit 1646
Read full office action

Prosecution Timeline

Dec 22, 2022
Application Filed
Mar 24, 2026
Non-Final Rejection — §103 (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
69%
Grant Probability
87%
With Interview (+18.2%)
2y 8m
Median Time to Grant
Low
PTA Risk
Based on 1409 resolved cases by this examiner. Grant probability derived from career allow rate.

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