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 .
DETAILED ACTION
Claims 1-18 and 23 are pending in the instant application.
Claims 6-18 and 23 are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected invention, there being no allowable generic or linking claim. Election was made without traverse in the reply filed on 3/2/2026.
Claims 3-4 are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected species, there being no allowable generic or linking claim. Election was made without traverse in the reply filed on 3/2/2026.
Restriction Response
Applicant’s election without traverse of Group I, an antibody-drug conjugate intermediate represented by formula (I) and the species represented by formula (4)
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in the reply filed on 3/2/2026 is acknowledged. The elected species in present in instant claims 1-2 and 5.
Priority
Should applicant desire to obtain the benefit of foreign priority under 35 U.S.C. 119(a)-(d) prior to declaration of an interference, a certified English translation of the foreign application must be submitted in reply to this action. 37 CFR 41.154(b) and
41.202(e).
Failure to provide a certified translation may result in no benefit being accorded
for the non-English application. The effective priority date is the filing date of
PCT/CN2022/128912 filed on 11/01/2022 in the absence of a certified translation of
CN202111285580.X filed on 11/02/2021.
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.
Claim 2 is 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 instant claim 2, the claims list embodiments of m, p, and X1 in lines 4-6 that are “preferably” selected. It is not clear whether the recitation of the preferably selected embodiments are preferred examples —and therefore not limiting—or are further limitations of the scope of the claim.
Claim Rejections – 35 USC § 103
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.
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.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
The factual inquiries 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.
Claims 1-2 and 5 are rejected under 35 U.S.C. 103 as being unpatentable over WO 2021/225892 (Zhu T et al. priority date 5/3/2020) and Elgersma RC et al. (Mol. Pharmaceutics 2015, 12, 6, 1813–1835).
Zhu taught an effective method of treatment of a subject with a Trop-2 expressing cancer comprising administering an anti-Trop-2 ADC comprising compound 1 (page 85, Table 2 and Fig. 6), wherein the structure of antibody drug intermediate compound 1 is:
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(page 77).
Zhu did not teach the elected species of:
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, but this is obvious in view of Elgersma.
Elgersma taught an ADC Linker-drug 2 was selected based on the properties of the corresponding trastuzumab conjugate, SYD983, which showed subnanomolar potencies against multiple human cancer cell lines, was highly efficacious in a BT-474 xenograft model, and had a long half-life in cynomolgus monkeys, in line with high stability in monkey and human plasma (abstract). Elgersma taught the ADC Linker-drug 2 comprised the structure of:
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(abstract). Elgersma taught the self-elimination module in the ADC releases the cytotoxic agent following proteolytic cleavage of the linker (scheme 5). Elgersma taught the less lipophilic nature of the substituents in the cyclization spacer led to lower levels of high-molecular weight ADC species (page 1821, right column, third paragraph).
Regarding instant claims 1-2 and 5, it would have been obvious for a person having ordinary skill in the art to take the effective anti-Trop-2 ADC for treating cancer comprising the antibody drug conjugate intermediate compound 1 with the structure:
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– and:
Exchange one self-immolative self-elimination module of
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for
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in view of Elgersma.
This is obvious because: 1a) Elgersma taught an ADC Linker-drug 2 was effective and had a long half-life in cynomolgus monkeys, in line with high stability in monkey and human plasma and the self-elimination module in the ADC effectively releases the cytotoxic agent following proteolytic cleavage of the linker; and 1b) Elgersma taught the less lipophilic nature of the substituents in the cyclization spacer led to lower levels of high-molecular weight ADC species.
There is a reasonable expectation of success because: 1a) Elgersma taught an ADC Linker-drug 2 was effective and had a long half-life in cynomolgus monkeys, in line with high stability in monkey and human plasma and the self-elimination module in the ADC effectively releases the cytotoxic agent following proteolytic cleavage of the linker; and 1b) Elgersma taught the less lipophilic nature of the substituents in the cyclization spacer led to lower levels of high-molecular weight ADC species. Thus, exchange of one effective self-immolative self-elimination module in an effective antibody drug conjugate for another would have a reasonable expectation of success.
This would produce an effective anti-Trop-2 ADC for treating cancer comprising an antibody drug conjugate intermediate with the structure:
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.
Conclusion
Claims 1-2 and 5 are rejected.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to JOHN J SKOKO III whose telephone number is (571)272-1107. The examiner can normally be reached M-F 8:30 - 5:00.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Julie Z Wu can be reached at (571)272-5205. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/J.J.S./Examiner, Art Unit 1643
/Karen A. Canella/Primary Examiner, Art Unit 1643
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