Prosecution Insights
Last updated: July 17, 2026
Application No. 18/578,343

IL-2 MUTEINS FOR TREATING CANCER OR INFECTION

Non-Final OA §103§112
Filed
Jan 11, 2024
Priority
Jul 23, 2021 — provisional 63/225,065 +1 more
Examiner
REYNOLDS, FRED H
Art Unit
Tech Center
Assignee
Merck Sharp & Dohme LLC
OA Round
1 (Non-Final)
33%
Grant Probability
At Risk
1-2
OA Rounds
5m
Est. Remaining
72%
With Interview

Examiner Intelligence

Grants only 33% of cases
33%
Career Allowance Rate
274 granted / 828 resolved
-26.9% vs TC avg
Strong +39% interview lift
Without
With
+39.1%
Interview Lift
resolved cases with interview
Typical timeline
2y 11m
Avg Prosecution
99 currently pending
Career history
936
Total Applications
across all art units

Statute-Specific Performance

§101
1.5%
-38.5% vs TC avg
§103
40.4%
+0.4% vs TC avg
§102
15.6%
-24.4% vs TC avg
§112
16.0%
-24.0% vs TC avg
Black line = Tech Center average estimate • Based on career data from 828 resolved cases

Office Action

§103 §112
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 . 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. Election/Restrictions Applicant’s election of group I (polypeptides) and SEQ ID 4 in the reply filed on 2 June, 2026 is acknowledged. Because applicant did not distinctly and specifically point out the supposed errors in the restriction requirement, the election has been treated as an election without traverse (MPEP § 818.01(a)). The requirement is deemed proper and is therefore made FINAL. Applicants have elected SEQ ID 4 (IL-2 with T3A, Y45R, and C125S mutations compared to native sequence). A search was conducted for this invention, and references rendering it obvious were found. As a result, claim 1 was examined and claims 2-31, and 43-45 have been withdrawn from consideration. Applicants have stated that they believe claims 2-8 read on their elected species. Applicants were required to elect a single, discrete, and disclosed formulation, not a genus of compounds. Claims 2-8 require sequences fused to the elected sequence, and so are properly withdrawn. Claims Status Claims 1-31 and 43-45 Claims 2-31 and 43-45 are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected invention or species, there being no allowable generic or linking claim. Election was made without traverse in the reply filed on 2 June, 2026. 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 1 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. Claim 1 requires an IL-2 mutein “comprising a first polypeptide.” First implies a second polypeptide, which is not described. This terminology makes it unclear if one of the amino acid sequences of claim 1 is sufficient to read on the claim. 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. 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. 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. Claim(s) 1 is rejected under 35 U.S.C. 103 as being unpatentable over Ast et al (US 20120244112). Ast et al discuss mutant IL-2 polypeptides with reduced IL-2Rα binding affinity (abstract). This is preferably done by a mutation at one or more of positions 42, 45, or 72, with Y45R described as an exemplary mutation (paragraph 77). Mutations at position 3 will eliminate a glycosylation site, with T3A given as an exemplary mutation (paragraph 85). Note that this mutation does not influence binding to CD25 (another name for IL-2Rα)(paragraph 305). C125S is mentioned as a mutation that can increase expression or stability (paragraph 91). These mutants can be linked to another compound, such as a targeting moiety or an antibody fragment (paragraph 15). Pharmaceutical formulations comprising the polypeptide dissolved in a carrier are discussed (paragraph 187). While this reference lists every mutation in applicant’s elected species, and what it does, there is no sequence described consisting of just those mutations, and they are pulled from different parts of the disclosure. This pattern fits obviousness better than anticipation. Conclusion Any inquiry concerning this communication or earlier communications from the examiner should be directed to FRED REYNOLDS whose telephone number is (571)270-7214. The examiner can normally be reached M-Th 9-3:30. Examiner interviews are available via telephone 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, Melissa Fisher can be reached at 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. /FRED H REYNOLDS/Primary Examiner, Art Unit 1658
Read full office action

Prosecution Timeline

Jan 11, 2024
Application Filed
Jul 01, 2026
Non-Final Rejection mailed — §103, §112 (current)

Precedent Cases

Applications granted by this same examiner with similar technology

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IL-10 MUTEINS AND FUSION PROTEINS THEREOF
3y 5m to grant Granted May 19, 2026
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Patent 12606600
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Patent 12590131
ANTIMICROBIAL PEPTIDES WITH ALPHA-CORE HELICES
1y 11m to grant Granted Mar 31, 2026
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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
33%
Grant Probability
72%
With Interview (+39.1%)
2y 11m (~5m remaining)
Median Time to Grant
Low
PTA Risk
Based on 828 resolved cases by this examiner. Grant probability derived from career allowance rate.

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