DETAILED ACTION
1. The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
2 Applicant's amendment, filed on 02/27/2026, is acknowledged.
3. Claims 1-21 are pending.
4. Applicant’s election without traverse of Group I, claims 1-15, 19 and 21, directed to a dimerized polypeptide comprising a heavy chain constant region 1 (CH1) and light chain constant region (CL), wherein CH1 and CL comprise natural-non-cysteine-to-cysteine amino acid substitutions and the species of (a) the amino acid substitutions (a) C220A in CH1 and C214A in CL and (b-2) L128C in CH1 and S121C in CL (b) the dimerized polypeptide is a monospecific antibody, (c) the antigen-binding protein further comprises a Fc region, wherein the Fc region is an IgG1 Fc region; and (d) the specific antigen target for the antigen-bindign protein is PD-1, filed on 02/27/2026, is acknowledged.
5. Claims 6-18 and 20 are withdrawn from further consideration pursuant to 37 CFR 1.142(b), as being drawn to nonelected inventions.
6. Claims 1-5, 19 and 21 are under examination as they read on a dimerized polypeptide comprising a heavy chain constant region 1 (CH1) and light chain constant region (CL), wherein CH1 and CL comprise natural-non-cysteine-to-cysteine amino acid substitutions and the species of (a) the amino acid substitutions (a) C220A in CH1 and C214A in CL and (b-2) L128C in CH1 and S121C in CL (b) the dimerized polypeptide is a monospecific antibody, (c) the antigen-binding protein further comprises a Fc region, wherein the Fc region is an IgG1 Fc region; and (d) the specific antigen target for the antigen-binding protein is PD-1.
7. Applicant’s IDS, filed 06/02/2023, is acknowledged.
8. The following is a quotation of 35 U.S.C. 112(b) (Pre AIA , 35 U.S.C. 112, second paragraph):
(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.
9. Claims 1-5, 19 and 21 are rejected under 35 U.S.C. 112(b), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which applicant regards as the invention.
A. Claims 1, 3, 5 and 21 recites “position 128 of CH1 and position 121 of CL”, “position L128C of CH1 and position S121C of CL”, “C220A in CH1 and C214A in CL; F170C in CH1 and T164C in CL; and T139R in CH1 and S114E in CL” and “at position 139 of CH1 and position 114 of CL”; respectively is indefinite, it is indefinite to recite amino acids positions without structural features for the comparison. It is suggested that the claims recite specific number scheme such as Kabat/EU numbering scheme in the claim to overcome the rejection. For Example, US Pat 8053562 discloses the same amino acid position but with different amino acid codename, see Table 1 below of the `562 patent which discloses position S128 and K129 while the instant claims recite L128 and A129.
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10. The following is a quotation of the appropriate paragraphs 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 –
(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.
11. Claims 1-3, 19 and 21 are rejected under 35 U.S.C. 102(a)(2) as being anticipated by WO 2021126538.
The `538 further teaches on Table 5 dimerized bsAb5 CP comprising a CH1 and CL, wherein : CH1 and CL comprise natural-non-cysteine-to-cysteine amino acid substitutions at positions:
(a) S131 of CH1 and P119.
(b) A129 of CH1 and S121 [00187].
The `538 publication teaches bispecific antibodies comprising:
a. a first heavy chain, HI ;
b. a second heavy chain, H2;
c. a first light chain, LI; and
d. a second light chain, L2; wherein the amino acid substitutions or the native amino acid in the CHI and CL regions are selected from:
(2) S131C and C220X in CHI, and P119C and C214X in CL; wherein X is S, A or G.
(13) A129C and C131X in CH1, and S121C and C214X in CL; wherein X is S, A or G (page 54).
Claim 21 is included because the claimed result of the substitutions would follow naturally and necessarily form substituting (2) S131C and C220X in CHI, and P119C and C214X in CL; wherein X is S, A or G or (13) A129C and C131X in CH1, and S121C and C214X in CL; wherein X is S, A or G (page 54).
The reference teachings anticipate the claimed invention.
12. Claims 1-3, 19 and 21 are rejected under 35 U.S.C. 102(a)(2) as being anticipated by US 20220411497 A1
The `497 publication teaches a bispecific antibody comprising the CH1 and CL regions comprise amino acid substitutions or a native amino acid at an amino acid are selected from:
[0017] (2) S131C and C220X in CH1, and P119C and C214X in CL;
[0025] (10) A129C and C220X in CH1, and S121C and C214X in CL;
[0028] (13) A129C and C131X in CH1, and S121C and C214X in CL; wherein X is selected from S, A or G [0036] [0137], [0145], [0148], [0225] , [0233], [0236] and published claim 1.
Claim 21 is included because the claimed result of the substitutions would follow naturally and necessarily form substituting (2) S131C and C220X in CHI, and P119C and C214X in CL; wherein X is S, A or G or (13) A129C and C131X in CH1, and S121C and C214X in CL; wherein X is S, A or G (page 54).
The reference teachings anticipate the claimed invention.
13. The art made of record and not relied upon is considered pertinent to applicant's disclosure:
(a) WO2017/205014 teaches the following mutations C220A and C214A
(b) 9,527,927 B2
(c) US 20140072581 A1 teaches disulfide (C214A/C220A) (see variant 707)
(d) CN112010982 (IDS).
The `982 publication of anti-GPCS/CD3 double antibody molecule comprising the modification of CH1170-CL164 (see Example 1).
14. Claims 4-5 are objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
15. Any inquiry concerning this communication or earlier communications from the examiner should be directed to MAHER M HADDAD whose telephone number is (571)272-0845. The examiner can normally be reached on Monday-Friday from7:00AM to 4:30PM. If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Misook Yu, can be reached at telephone number 571-272-0839. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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May 3, 2026
/MAHER M HADDAD/ Primary Examiner, Art Unit 1644
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