Prosecution Insights
Last updated: April 19, 2026
Application No. 18/030,757

Deuterated Camptothecin Derivative And Antibody-drug Conjugate Thereof

Non-Final OA §103§112§DP
Filed
Apr 06, 2023
Examiner
PATEL, SAGAR S
Art Unit
1626
Tech Center
1600 — Biotechnology & Organic Chemistry
Assignee
BAILI-BIO (CHENGDU) PHARMACEUTICAL CO., LTD.
OA Round
1 (Non-Final)
76%
Grant Probability
Favorable
1-2
OA Rounds
2y 8m
To Grant
99%
With Interview

Examiner Intelligence

Grants 76% — above average
76%
Career Allow Rate
345 granted / 455 resolved
+15.8% vs TC avg
Strong +34% interview lift
Without
With
+33.8%
Interview Lift
resolved cases with interview
Typical timeline
2y 8m
Avg Prosecution
30 currently pending
Career history
485
Total Applications
across all art units

Statute-Specific Performance

§101
1.0%
-39.0% vs TC avg
§103
32.8%
-7.2% vs TC avg
§102
20.7%
-19.3% vs TC avg
§112
23.6%
-16.4% vs TC avg
Black line = Tech Center average estimate • Based on career data from 455 resolved cases

Office Action

§103 §112 §DP
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 . Status of the Claims Claims 1 – 26 are pending. Claims 7 – 12 and 16 – 20 are rejected. Claims 1 – 6, 13 – 16 and 21 – 26 are withdrawn. Requirement for Unity of Invention As provided in 37 CFR 1.475(a), a national stage application shall relate to one invention only or to a group of inventions so linked as to form a single general inventive concept (“requirement of unity of invention”). Where a group of inventions is claimed in a national stage application, the requirement of unity of invention shall be fulfilled only when there is a technical relationship among those inventions involving one or more of the same or corresponding special technical features. The expression “special technical features” shall mean those technical features that define a contribution which each of the claimed inventions, considered as a whole, makes over the prior art. The determination whether a group of inventions is so linked as to form a single general inventive concept shall be made without regard to whether the inventions are claimed in separate claims or as alternatives within a single claim. See 37 CFR 1.475(e). When Claims Are Directed to Multiple Categories of Inventions As provided in 37 CFR 1.475 (b), a national stage application containing claims to different categories of invention will be considered to have unity of invention if the claims are drawn only to one of the following combinations of categories: (1) A product and a process specially adapted for the manufacture of said product; or (2) A product and a process of use of said product; or (3) A product, a process specially adapted for the manufacture of the said product, and a use of the said product; or (4) A process and an apparatus or means specifically designed for carrying out the said process; or (5) A product, a process specially adapted for the manufacture of the said product, and an apparatus or means specifically designed for carrying out the said process. Otherwise, unity of invention might not be present. See 37 CFR 1.475 (c). Restriction is required under 35 U.S.C. 121 and 372. This application contains the following inventions or groups of inventions which are not so linked as to form a single general inventive concept under PCT Rule 13.1. In accordance with 37 CFR 1.499, applicant is required, in reply to this action, to elect a single invention to which the claims must be restricted. Group I, claims 1 – 6 and 23, directed to a deuterated camptothecin derivative of Formula D, and an pharmaceutical composition comprising said derivative. Group II, claims 7 – 20, directed to a drug-linker compound of Formula -L-X-D2, and an antibody-drug conjugate having the Formula (Ab-L-X-Dr). Group III, claim 21, directed to a method for preparing the compound of claim 14. Group IV, claim 22, directed to a method for preparing an antibody-drug conjugate having the Formula (Ab-L-X-Dr). Group V, claims 24 – 26, directed to the use for purpose of preparing drugs for the treatment or prevention of tumor, of the deuterated camptothecin derivative or antibody-drug conjugate of claims 1 – 20. As written, claims 24 – 26 are directed towards the "use" of a compound and contain non-statutory subject matter. Refer to 35 U.S.C. §101 Inventions patentable: Whoever invents or discovers any new and useful process, machine, manufacture, or composition of matter or any new and useful improvement thereof, may obtain a patent therefor, subject to the conditions and requirements of this title. Thus, the Examiner will interpret claims 24 – 26 as a method of using the deuterated camptothecin derivative or antibody-drug conjugate of claims 1 – 20. The groups of inventions listed above do not relate to a single general inventive concept under PCT Rule 13.1 because, under PCT Rule 13.2, they lack the same or corresponding special technical features for the following reasons: There is no special technical feature linking Group I – V. The inventions of these groups require the technical feature of the deuterated camptothecin derivative of Formula D. However, this technical feature is not a special technical feature because it does not make a contribution over the prior art in view of Naito et al. US 10,155,821 B2. Naito et al. teach an antibody-drug conjugate (2) (see, e.g., columns 67-68): PNG media_image1.png 414 1000 media_image1.png Greyscale . Election of Species This application contains claims directed to more than one species of the generic invention. These species are deemed to lack unity of invention because they are not so linked as to form a single general inventive concept under PCT Rule 13.1. The species are as follows: If any one of Groups I – IV is elected, a specific compound of deuterated camptothecin derivative of Formula D, a drug-linker compound of Formula -L-X-D2, an antibody-drug conjugate having the Formula (Ab-L-X-Dr), If Group V is elected, (a) a specific compound of deuterated camptothecin derivative of Formula D, a drug-linker compound of Formula -L-X-D2, an antibody-drug conjugate having the Formula (Ab-L-X-Dr), and (b) a single tumor to be treated. Applicant is required, in reply to this action, to elect a single species of the of deuterated camptothecin derivative of Formula D, a drug-linker compound of Formula -L-X-D2, an antibody-drug conjugate having the Formula (Ab-L-X-Dr), or a single grouping of patentably indistinct species, for prosecution on the merits to which the claims shall be restricted if no generic claim is finally held to be allowable. For example, the compounds as claimed in claim 6. Applicant is requested to identify each of the variables associated with the respective formulae (Formula D, Formula -L-X-D2, or Formula (Ab-L-X-Dr)). For example, in Formula D, variables R1-R10, R2’-R5’, X, and Ra-Rd. The reply must also identify the claims readable on the elected species, including any claims subsequently added. An argument that a claim is allowable or that all claims are generic is considered non-responsive unless accompanied by an election. Upon the allowance of a generic claim, applicant will be entitled to consideration of claims to additional species which are written in dependent form or otherwise require all the limitations of an allowed generic claim. Currently, claims 1 and 3 – 17 are generic. Applicant is advised that the reply to this requirement to be complete must include (i) an election of an invention and species to be examined even though the requirement may be traversed (37 CFR 1.143) and (ii) identification of the claims encompassing the elected invention. Traversal The election of an invention or species may be made with or without traverse. To preserve a right to petition, the election must be made with traverse. If the reply does not distinctly and specifically point out supposed errors in the restriction requirement, the election shall be treated as an election without traverse. Traversal must be presented at the time of election in order to be considered timely. Failure to timely traverse the requirement will result in the loss of right to petition under 37 CFR 1.144. If claims are added after the election, applicant must indicate which of these claims are readable on the elected invention or species. Should applicant traverse on the ground that the inventions have unity of invention (37 CFR 1.475(a)), applicant must provide reasons in support thereof. Applicant may submit evidence or identify such evidence now of record showing the inventions to be obvious variants or clearly admit on the record that this is the case. Where such evidence or admission is provided by applicant, if the examiner finds one of the inventions unpatentable over the prior art, the evidence or admission may be used in a rejection under 35 U.S.C. 103 or pre-AIA 35 U.S.C. 103(a) of the other invention. Joint Inventors Applicant is reminded that upon the cancelation of claims to a non-elected invention, the inventorship must be corrected in compliance with 37 CFR 1.48(a) if one or more of the currently named inventors is no longer an inventor of at least one claim remaining in the application. A request to correct inventorship under 37 CFR 1.48(a) must be accompanied by an application data sheet in accordance with 37 CFR 1.76 that identifies each inventor by his or her legal name and by the processing fee required under 37 CFR 1.17(i). Rejoinder The examiner has required restriction between product or apparatus claims and process claims. Where applicant elects claims directed to the product/apparatus, and all product/apparatus claims are subsequently found allowable, withdrawn process claims that include all the limitations of the allowable product/apparatus claims should be considered for rejoinder. All claims directed to a nonelected process invention must include all the limitations of an allowable product/apparatus claim for that process invention to be rejoined. In the event of rejoinder, the requirement for restriction between the product/apparatus claims and the rejoined process claims will be withdrawn, and the rejoined process claims will be fully examined for patentability in accordance with 37 CFR 1.104. Thus, to be allowable, the rejoined claims must meet all criteria for patentability including the requirements of 35 U.S.C. 101, 102, 103 and 112. Until all claims to the elected product/apparatus are found allowable, an otherwise proper restriction requirement between product/apparatus claims and process claims may be maintained. Withdrawn process claims that are not commensurate in scope with an allowable product/apparatus claim will not be rejoined. See MPEP § 821.04. Additionally, in order for rejoinder to occur, applicant is advised that the process claims should be amended during prosecution to require the limitations of the product/apparatus claims. Failure to do so may result in no rejoinder. Further, note that the prohibition against double patenting rejections of 35 U.S.C. 121 does not apply where the restriction requirement is withdrawn by the examiner before the patent issues. See MPEP § 804.01. Telephonic Election/Restriction During telephone conversation and electronic communication with Applicant’s representative, Feng Wan, on December 4, 2025, a provisional election was made without traverse to prosecute the invention of Group II, claims 7 – 20. Affirmation of this election must be made by applicant in replying to this Office action. Further, Applicant specifically elected the drug-linker compound of Formula -L-X-D2: PNG media_image2.png 366 386 media_image2.png Greyscale , wherein: PNG media_image3.png 256 642 media_image3.png Greyscale The compound reads on claims 9 – 12, wherein the linker unit L is -L1-L2-L3-L4-: L1 is –(Succinimido-3-yl)-Y-C(O), Y is C1 alkyl substituted with C1 alkyl further substituted with the moiety -NH-CH2-COOH, L2 is a chemical bond or -NR6(CH2CH2O)pCH2C(O)-, wherein p is 0 and R6 is hydrogen, L3 is a peptide residue having 3-4 amino acids, and L4 is -NR7(CR8R9)q-, wherein q is 1, and R7, R8 and R9 are hydrogen. Examination: Applicant’s elected species read on claims 7 – 12 and 16 (improperly numbered) – 20. The elected species appears allowable over the prior art. In accordance with MPEP §803.02, the search has been further extended to include the scope, wherein Y is C5 alkyl. Because the scope is not allowable, the search has not been further extended to include the scope of non-elected species. Claims 1 – 6, 13 – 16, and 21 – 26 are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected inventions/ species, there being no allowable generic or linking claim. Priority PNG media_image4.png 90 392 media_image4.png Greyscale Receipt is acknowledged of certified copies of papers required by 37 CFR 1.55. However, the filing date of the priority document is not perfected unless Applicant has filed both, a certified copy of the document and an English language translation (if the document is not in English) (see, 37 CFR 1.55(g)(3)). Accordingly, the claims are examined with an effective filing date of October 9, 2021 (the filing date of the PCT Application). Claim Objections Claims 7, 9 – 10 and 16 – 17 are objected to because of the following informalities: Claim 7: Each definition of the variables contains grammatical issue because the variables do not recite proper conjunction. See, e.g., page 6, lines 3, 7, 9, 14, 17 and 21. In order to overcome the objection, Applicant may amend the variables as follows: R1, R7, and R10… R2, R2’, R3, R3’, R4, R4’, R5, R5’, R8, and R9… Ra, and Rb… , and Rc, and Rd… . Page 6, Line 14: The terms “their connected carbon atoms” is grammatically incorrect because the variables Ra and Rb are only connected to one (singular form) carbon atom. Emphasis added. In order to overcome the objection, Applicant may amend the terms as follows: “the connected carbon atom”. Page 6, Line 21: The terms “their connected carbon atoms” is grammatically incorrect because the variables Ra and Rb are only connected to one (singular form) carbon atom. Emphasis added. In order to overcome the objection, Applicant may amend the terms as follows: “the connected carbon atom”. Claim 9: Each definition of the variables recites the limitations “selected from … or …”. Emphasis added. See, e.g., page 7, lines 5, 7 – 8, 11 – 13, 15 – 17 of the claim; and page 8, lines 1 – 6. The limitations are grammatically incorrect because it does not recite proper Markush group language. In order to overcome the objections, Applicant may amend the limitations as follows (for example, page 7, line 5 of the claim): “L1 is selected from -(Succinimido-3-yl-N)-Y-C(O)-, -CH2-C(O)-NR5-Y-C(O)- [[or]] and -C(O)-Y-C(O)-”. Claim 10: Each definition of the variables recites the limitations “selected from … or …”. Emphasis added. See, e.g., page 8, lines 3 – 6, 8 – 11 and 15 – 20 of the claim. The limitations are grammatically incorrect because it does not recite proper Markush group language. In order to overcome the objections, Applicant may amend the limitations as follows (for example, page 8, lines 15 – 17 of the claim): “R5, R6, R7 are… selected from hydrogen, deuterium, halogen, alkyl, deuterated alkyl, haloalkyl, cycloalkyl, cycloalkylalkyl, alkoxyalkyl, heterocyclic, aryl, and substituted aryl [[and]] or heteroaryl”. Claim 16: The claims present two claims with the same number (16). The second claim 16 is improperly numbered. Applicant is requested to renumber the second claim 16 as claim 17. Further, Applicant may also need to renumber subsequent claims 17 – 26 to recite correct numbering. Each definition of the variables contains grammatical issue because the variables do not recite proper conjunction. See, e.g., page 16, lines 8, 11 and 13 of the claim; and page 17, lines 1, 5 and 9. In order to overcome the objection, Applicant may amend the variables as follows: R1, R7, and R10… R2, R2’, R3, R3’, R4, R4’, R5, R5’, R8, and R9… Ra, and Rb… , and Rc, and Rd… . Page 16, line 13 – 16: The definition of the variables Ra and Rb recites the limitation “selected from … aryl, substituted aryl and heteroaryl”. The limitation is grammatically incorrect because it does not recite proper Markush group language. In order to overcome the objections, Applicant may amend the limitations as follows: “selected from … aryl, and substituted aryl [[and]] or heteroaryl”. Claim 17: Each definition of the variables recites the limitations “selected from … or …”. Emphasis added. See, e.g., page 17, lines 5 – 13 of the claim; and page 18, lines 2 – 12. The limitations are grammatically incorrect because it does not recite proper Markush group language. In order to overcome the objections, Applicant may amend the limitations as follows (for example, page 18, lines 1 – 4): “… the amino acids are optionally further substituted by one or more substituents selected from deuterium, halogen, hydroxyl, cyano, amino, nitro, alkyl, substituted alkyl, alkoxy, cycloalkyl [[or]] and substituted cycloalkyl”. 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. Claims 11 – 12 are rejected under 35 U.S.C. 112(b) as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor, regards as the invention. A broad range or limitation together with a narrow range or limitation that falls within the broad range or limitation (in the same claim) may be considered indefinite if the resulting claim does not clearly set forth the metes and bounds of the patent protection desired. See MPEP § 2173.05(c). In the present instance, Claim 11 recites the broad recitation “The drug-linker compound according to claim 9 or a pharmaceutically acceptable salt or solvent thereof”. See, lines 1-2 of the claim. The broad limitation refers to the definition of L3 as claimed in claim 9. Claim 11 also recites the limitation “L3 is preferably a peptide comprising one, two, or more amine acids selected from phenylalanine and glycine; the most preferred is a tetrapeptide residue comprising glycine-glycine-phenylalanine-glycine” which is the narrower statement of the range/limitation. Similarly, claim 12 recites the broad recitation “The drug-linker compound according to claim 9 or a pharmaceutically acceptable salt or solvent thereof”. See, lines 1-2 of the claim. The broad limitation refers to the definition of L4 as claimed in claim 9. Claim 12 also recites the limitation “L4 is preferably -NHCH2-” which is the narrower statement of the range/limitation. The claims are considered indefinite because there is a question or doubt as to whether the feature introduced by such narrower language is (a) merely exemplary of the remainder of the claim, and therefore not required, or (b) a required feature of the claims. In order to overcome the rejection, Applicant may amend as follows: Claim 11, lines 2 – 4 of the claim: “… L3 is Claim 12, line 2 of the claim: “… wherein L4 is2-”. 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. Claims 7 – 12 and 16 – 20 are rejected under 35 U.S.C. 103 as being unpatentable over Xu et al. CA3114137 A1 (pub. April 2, 2020) in view of Timmins et al., Expert Opin Ther Pat. Author manuscript (2015), pp. 1-19. Determining the scope and contents of the prior art Xu et al. teach an antibody-drug conjugate (ADC-1) of Example 21. See, e.g., page 113, lines 1-2. The antibody-drug conjugate (ADC-1) of Example 21 is presented below: PNG media_image5.png 483 1363 media_image5.png Greyscale , wherein: n is 5.09. See, e.g., page 113, line 16. Compared to instant claims, the antibody-drug conjugate (ADC-1) of Example 21 teach the drug-linker compound of Formula -L-X-D2 as presented below: PNG media_image2.png 366 386 media_image2.png Greyscale , wherein: R2, R2’, R3, R3’, R4, R4’, R5, R5’, R8, R9 and R10 are hydrogen, R1 and R7 are C1 alkyl, X is -C(O)-CRaRb-(CRcRd)n-O-, n is 0, One of Ra or Rb is hydrogen, and the other is -CF3, L is PNG media_image6.png 264 904 media_image6.png Greyscale , the linker unit L is -L1-L2-L3-L4-: L1 is –(Succinimido-3-yl)-Y-C(O), Y is C5 alkyl, L2 is a chemical bond or -NR6(CH2CH2O)pCH2C(O)-, wherein p is 0 and R6 is hydrogen, L3 is a peptide residue having 3-4 amino acids, and L4 is -NR7(CR8R9)q-, wherein q is 1, and R7, R8 and R9 are hydrogen. Ascertaining the differences between the prior art and the claims at issue The difference between the antibody-drug conjugate (ADC-1) of Example 21 and the claims is that hydrogen atom is bonded to one of Ra or Rb in variable X (in compound ADC-1) PNG media_image7.png 171 116 media_image7.png Greyscale instead of deuterium as instantly claimed Rationale for a prima facie case of obviousness According to MPEP §2141(III), one of the rationales in the KSR decision states “(G) Some teaching, suggestion, or motivation in the prior art that would have led one of ordinary skill to modify the prior art reference or to combine prior art reference teachings to arrive at the claimed invention”. KSR, 550 U.S. at 418, 82 USPQ2d at 1396. While Xu does not explicitly disclose the deuterated form of the antibody-drug conjugate (ADC-1) of Example 21, Xu teaches that the compounds of generic formula (I) can be present in various deuterated forms. Xu states “[e]ach of the available hydrogen atom attached to a carbon atom can be independently replaced by a deuterium atom… [t]hose skilled in the art can synthesize a compound of formula (I) in a deuterated form with reference to the relevant literatures… [t]he compound of formula (I) in deuterated form can be prepared by employing commercially available deuterated raw materials, or they can be synthesized by conventional techniques with deuterated reagents…”. See, e.g., page 53, lines 7-13. It would have been obvious to a person having ordinary skill in the art to deuterate the drug-linker compound of Formula -L-X-D2 given there is always a need to enhance the pharmaceutical properties of a compound (e.g., increased in vivo half-life) without significantly altering its basic chemical structure, or there is always a need to reduce the time, cost, risk, and statistical imprecision of pharmacokinetic studies (e.g., measure bioavailability or identify metabolites), and there is only a limited number of ways that this can be done, it would have been obvious to a PHOSITA to pursue a potential solution that has a reasonable expectation of success. See, e.g., Timmins et al., page 4, 1st-2nd paragraphs; KSR International Co. v. Teleflex Inc., 1385, 1397; Pfizer, Inc. v. Apotex, Inc., 82 USPQ2d 1321; Alza Corp. v. Mylan Laboratories, Inc., 80 USPQ2d 1001; In re Kubin, 90 USPQ2d 1417; In re O’Farrell, 7 USPQ2d 1673, 1681; In re Eli Lilly & Co., 14 USPQ2d 1741; In re Ball Corp., 18 USPQ2d 1491. Double Patenting The nonstatutory double patenting rejection is based on a judicially created doctrine grounded in public policy (a policy reflected in the statute) so as to prevent the unjustified or improper timewise extension of the “right to exclude” granted by a patent and to prevent possible harassment by multiple assignees. A nonstatutory double patenting rejection is appropriate where the conflicting claims are not identical, but at least one examined application claim is not patentably distinct from the reference claim(s) because the examined application claim is either anticipated by, or would have been obvious over, the reference claim(s). See, e.g., In re Berg, 140 F.3d 1428, 46 USPQ2d 1226 (Fed. Cir. 1998); In re Goodman, 11 F.3d 1046, 29 USPQ2d 2010 (Fed. Cir. 1993); In re Longi, 759 F.2d 887, 225 USPQ 645 (Fed. Cir. 1985); In re Van Ornum, 686 F.2d 937, 214 USPQ 761 (CCPA 1982); In re Vogel, 422 F.2d 438, 164 USPQ 619 (CCPA 1970); In re Thorington, 418 F.2d 528, 163 USPQ 644 (CCPA 1969). A timely filed terminal disclaimer in compliance with 37 CFR 1.321(c) or 1.321(d) may be used to overcome an actual or provisional rejection based on nonstatutory double patenting provided the reference application or patent either is shown to be commonly owned with the examined application, or claims an invention made as a result of activities undertaken within the scope of a joint research agreement. See MPEP § 717.02 for applications subject to examination under the first inventor to file provisions of the AIA as explained in MPEP § 2159. See MPEP § 2146 et seq. for applications not subject to examination under the first inventor to file provisions of the AIA . A terminal disclaimer must be signed in compliance with 37 CFR 1.321(b). The filing of a terminal disclaimer by itself is not a complete reply to a nonstatutory double patenting (NSDP) rejection. A complete reply requires that the terminal disclaimer be accompanied by a reply requesting reconsideration of the prior Office action. Even where the NSDP rejection is provisional the reply must be complete. See MPEP § 804, subsection I.B.1. For a reply to a non-final Office action, see 37 CFR 1.111(a). For a reply to final Office action, see 37 CFR 1.113(c). A request for reconsideration while not provided for in 37 CFR 1.113(c) may be filed after final for consideration. See MPEP §§ 706.07(e) and 714.13. The USPTO Internet website contains terminal disclaimer forms which may be used. Please visit www.uspto.gov/patent/patents-forms. The actual filing date of the application in which the form is filed determines what form (e.g., PTO/SB/25, PTO/SB/26, PTO/AIA /25, or PTO/AIA /26) should be used. A web-based eTerminal Disclaimer may be filled out completely online using web-screens. An eTerminal Disclaimer that meets all requirements is auto-processed and approved immediately upon submission. For more information about eTerminal Disclaimers, refer to www.uspto.gov/patents/apply/applying-online/eterminal-disclaimer. Claims 7 – 12 and 16 – 20 are provisionally rejected on the ground of nonstatutory double patenting as being unpatentable over claims 9 – 15 and 18 – 21 of copending Application No. 18/030,754 (U.S. Publication 2025/0276078 A1) in view of Timmins et al., Expert Opin Ther Pat. Author manuscript (2015), pp. 1-19. Although the claims at issue are not identical, they are not patentably distinct from each other because: Determining the scope and contents of the copending Application Claim 9 in US ‘754 claims a linker-drug conjugate comprising the camptothecin derivative L-X-D: PNG media_image8.png 250 274 media_image8.png Greyscale Claim 21 in US ‘754 specifically claims the conjugate: PNG media_image9.png 282 626 media_image9.png Greyscale , wherein: Ab is a ligand unit, and n is selected from integers or decimals within 1-20. With respect to instant claims, the claims in US ‘754 teach the antibody-drug conjugate, wherein hydrogen atoms are bonded to the carbon atoms in variable X PNG media_image10.png 54 122 media_image10.png Greyscale instead of containing at least one deuterium. The specification of US ‘754 defines “[t]he invention also includes various forms of deuteration… [e]ach available hydrogen atom attached to a carbon atom can be independently replaced by a deuterium atom… [a] person skilled in the art of this field can synthesize deuterated compounds by referring to relevant literature… [i]n the preparation of deuterium compounds, commercially available deuterium initiation materials may be used, or they may be synthesized using conventional techniques using deuterium reagents”. See, e.g., page 57, lines 16 – 21. It would have been obvious to a person having ordinary skill in the art to deuterate the drug-linker compound of Formula -L-X-D2 given there is always a need to enhance the pharmaceutical properties of a compound (e.g., increased in vivo half-life) without significantly altering its basic chemical structure, or there is always a need to reduce the time, cost, risk, and statistical imprecision of pharmacokinetic studies (e.g., measure bioavailability or identify metabolites), and there is only a limited number of ways that this can be done, it would have been obvious to a PHOSITA to pursue a potential solution that has a reasonable expectation of success. See, e.g., Timmins et al., page 4, 1st-2nd paragraphs; KSR International Co. v. Teleflex Inc., 1385, 1397; Pfizer, Inc. v. Apotex, Inc., 82 USPQ2d 1321; Alza Corp. v. Mylan Laboratories, Inc., 80 USPQ2d 1001; In re Kubin, 90 USPQ2d 1417; In re O’Farrell, 7 USPQ2d 1673, 1681; In re Eli Lilly & Co., 14 USPQ2d 1741; In re Ball Corp., 18 USPQ2d 1491. The claims in US ‘754 render the instant claims unpatentable for obvious-type double patenting. This is a provisional nonstatutory double patenting rejection because the patentably indistinct claims have not in fact been patented. Conclusion Any inquiry concerning this communication or earlier communications from the examiner should be directed to Sagar Patel whose telephone number is (571)272-1317. The examiner can normally be reached Monday - Friday: 9am to 5pm EST. 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, Amy L. Clark can be reached at (571) 272-1310. 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. /Sagar Patel/Examiner, Art Unit 1626 /KAMAL A SAEED/Primary Examiner, Art Unit 1626
Read full office action

Prosecution Timeline

Apr 06, 2023
Application Filed
Dec 13, 2025
Non-Final Rejection — §103, §112, §DP (current)

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2y 5m to grant Granted Mar 31, 2026
Patent 12589096
RUXOLITINIB FORMULATION FOR REDUCTION OF ITCH IN ATOPIC DERMATITIS
2y 5m to grant Granted Mar 31, 2026
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
76%
Grant Probability
99%
With Interview (+33.8%)
2y 8m
Median Time to Grant
Low
PTA Risk
Based on 455 resolved cases by this examiner. Grant probability derived from career allow rate.

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