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 16- 19 and 21-35 are pending. Claims 1-15 and 20 are cancelled. Claims 16-19 and 21-35 have been examined. Priority This application is a 371 of PCT/US22/19839 03/10/2022 PCT/US22/19839 has PRO 63/159,336 03/10/2021 Information Disclosure Statement The information disclosure statement s (IDS) submitted on 5/9/2025 and 2/6/2026 are in compliance with the provisions of 37 CFR 1.97. Accordingly, the information disclosure statement has been considered by the examiner. Claim Objections Claim s 16 , 21 and 25- 26 are objected to because of the following informalities: Claim 16 contains the acronym “ CD81 ”, and an acronym in the first instance of claims should be expanded upon/spelled out as “ cluster of differentiation 81 ” with the acronym indicated in parentheses as ( CD81 ). The abbreviations can be used thereafter. Furthermore, the examiner suggests claim 16 should be revised as follows. “ An affinity agent comprising a ligand that binds to cluster of differentiation 81 (CD81), wherein the ligand comprises the cyclic peptide comprising the amino acid sequence X 1 YWRB 1 VWFPHAQGB 2 VX 2 X 2 (SEQ ID NO: 1), and where X 1 is H or N, each X 2 is independently S or T, and B 1 and B 2 are independently any amino acid through which the peptide is cyclized. ” With respect to claims 21 and 25, the claims have defined cyclic peptide sequences in the sequence listing but claims 21 and 25 are further object to as depending on the rejected claim 16. Claim 26 is objected to because a claim should has a single period “,” at the end of claim. Claim 26 contains more than one periods. Appropriate correction is required. Claim Rejections - 35 USC § 112 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 appl icant regards as his invention. Claims 16 - 19 , 2 2-24, 26 -2 7, and 32-35 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. Claim 16 is unclear for the reasons as follows I t is unclear whether the two X 2 residues are the same or different residues . I t is unclear with respect to the meaning of the word “units” of B1 and B2 in claim 16. MPEP 2173.02 (I) states “During examination, after applying the broadest reasonable interpretation to the claim, if the metes and bounds of the claimed invention are not clear, the claim is indefinite and should be rejected. Zletz, 893 F.2d at 322, 13 USPQ2d at 1322. For example, if the language of a claim, given its broadest reasonable interpretation, is such that a person of ordinary skill in the relevant art would read it with more than one reasonable interpretation, then a rejection under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112 , second paragraph is appropriate.” Claims 17- 19 , 2 2 - 24, and 26- 27 are rejected as depending on claim 16. Claim 19 is unclear with respect to the structure of the actual cyclic peptide conjugated with a linker peptide. Furthermore, the word “optionally” is interpreted as a preferred emb o diment with lysine or cysteine as a reactive residue in the linker. The examiner suggests claim 19 to be revised as “ The affinity agent of claim 16, wherein a linker peptide is attached to the C-terminus of SEQ ID NO: 1, and wherein the linker peptide is 1 to 10 amino acids in length and comprises a reactive residue selected from lysine or cysteine. ” With respect to claim 32 ( depending on claim 1 ) , it is unclear with respect to what is encompassed within the affinity agent recited in claim 32 because claim 1 has been cancelled. Claim 33 is rejected as depending on claim 32 and Claim 35 is further rejected for depending on claim 33. With respect to claim 34, the preamble “The method of claim 26” in claim 34 is indefinite because claim 26 is an affinity agent not a method. Examiner note: The examiner did not find a prior art teaching the cyclic peptide formula SEQ ID NO: 1 current under 112(b) rejection. The independent claims 28-31 are allowable . The closest prior art Dodson et al. ( WO 2020/242988 A2 , cited in IDS ) teach es an affinity ligand peptide comprising a cyclic portion with substitution, deletion, or deletion [0012]. Dodson et al. further show the cyclic peptide sequences as SEQ ID Nos: 1-47 [0097], but Dodson et al. did not teach or suggest a peptide sequence reading on the instant peptide formula of SEQ ID NO: 1. Conclusion Claims 16-19, 22-24, 26-27, and 32-35 are rejected under 35 U.S.C. 112(b) Claims 16 and 26 are objected to due to minor informalities . Claims 21 and 25 are objected as depending on the rejected base claim of claim 16 Claims 28-31 are allowed. Any inquiry concerning this communication or earlier communications from the examiner should be directed to FILLIN "Examiner name" \* MERGEFORMAT JIA-HAI LEE whose telephone number is FILLIN "Phone number" \* MERGEFORMAT (571)270-1691 . The examiner can normally be reached FILLIN "Work Schedule?" \* MERGEFORMAT Mon-Fri from 9:00 AM to 6:00 PM . 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, FILLIN "SPE Name?" \* MERGEFORMAT Melissa Fisher can be reached at FILLIN "SPE Phone?" \* MERGEFORMAT 571-270-7430 . 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. /J.L/ Examiner, Art Unit 1658 07-March-2026 /LI N KOMATSU/ Primary Examiner, Art Unit 1658