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 .
Information Disclosure Statement
The information disclosure statement (IDS) submitted on 10/11/2024. The submission is in compliance with the provisions of 37 CFR 1.97. Accordingly, the information disclosure statement is being considered by the examiner.
Status of the Claims
Claims 1-5 are pending in this application.
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.
Claims 1-5 are rejected under 35 U.S.C. 103 as being unpatentable over Tsubusaki et al. (US 2020/0010620 A1 – Pub. Date: Jan. 9th, 2020 – cited in IDS) (“Tsubusaki”).
Regarding claim 1, Tsubusaki discloses the compounds of general formulae 3-4 (page 7) as hydrophilic polymers capable of forming prodrugs of drugs containing amino groups or the like in order to overcome restrictions of conventional hydrophilic polymer pro-drugs (abstract) – this is the same intended use of the instant compounds. Tsubusaki’s compounds read on the instant claims when: R2-7 are each independently a hydrocarbon group having from 1 to 10 carbon atoms or a hydrogen atom; R10 is a hydrocarbon; R8-9 are each independently a hydrocarbon group having from 1 to 9 carbon atoms or a hydrogen atom; A1 can be a phenylene group; Z1 can be a bond; E1 is a leaving group; m can be 0 or 1 ([0043] to [0049]).
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Tsubusaki specifically discloses their preferred embodiments 43 and 44 below (page 22), which render the compounds of the instant claims obvious when: P1 represents a ‘residue obtained by removing a hydroxy group from a polyoxythylene derivative having the terminal hydroxy group’; R1-5, 7-12 are H; m = 0; and E1 is
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or
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(reading broadly on ‘leaving groups’). Tsubusaki discloses their acetals hydrolyzed at pH of 7.4 (reading on a physiological condition, as stated in the instant spec. ([0017]) – see [0200] in Tsubusaki) While Tsubusaki’s preferred embodiments do not have a hydrocarbon in the position corresponding to instant R6 and show meta-substitution of the group corresponding to instant P1 on the phenylene corresponding to their A1, when the instant claims require either ortho or para substitution; Tsubusaki teaches their R10 (corresponding to instant R6) can be a hydrocarbon, including methyl, etc. (see [0043]) and their phenylene A1 in formulae 3-4 allows for substitution in any of the limited positions around phenyl. Therefore, Tsubusaki discloses a relatively broad genus which encompasses the instant subgenus of compounds.
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Therefore, regarding claim 1, one having ordinary skill in the art would have found the claimed compounds prima facie obvious, since they are generically embraced by Tsubusaki’s disclosed formulae and preferred embodiments; In re Susi, 440 F.2d 442, 169 USPQ 423 (CCPA 1971). See MPEP 2144.08. The requisite motivation for arriving at the claimed compounds stems from the fact that they fall within the generic class of hydrophilic polymer compounds for the preparation of pro-drugs disclosed by Tsubusaki. Accordingly, one having ordinary skill in the art would have been motivated to prepare any of the compounds embraced by the disclosed generic formula, including those encompassed by the claims.
Regarding the position of the groups around the phenyl rings, Applicant is advised that a novel useful compound that is isomeric with the prior art compound is unpatentable unless it possesses some unobvious or unexpected beneficial property not possessed by the prior art compound. In re Norris, 179 F.2d. 970, 84 USPQ 458 (CCPA 1950). Therefore, it would have been obvious to one of ordinary skill to expect similar properties of structurally similar compounds since they are suggestive of one another. It has been held that a compound, which is structurally isomeric with a compound of the prior art, is prima facie obvious absent unexpected results. In re Finely, 81 USPQ 383 (CCPA 1949); 84 USPQ 458 (CCPA 1950).
Regarding claim 2, Tsubusaki discloses their compounds wherein the groups corresponding to instant R1-2 are H; R3-5, 12 can be H or Me; and the group corresponding to m is 0.
Regarding claim 5, Tsubusaki discloses the conjugate compounds of formula 20, which degrade depending on the pH to release a drug ([0051]; see also page 10), wherein the groups are defined as above for formulae 3-4. Tsubusaki’s compounds read on the instant claims when m = 0 and D1 ‘represents a residue obtained by removing an amino group, that constitutes a carbamate bond, from an amino group contained in a functional biomolecule’.
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Therefore, regarding claim 5, one having ordinary skill in the art would have found the claimed compounds prima facie obvious, since they are generically embraced by Tsubusaki’s disclosed formulae and preferred embodiments. The requisite motivation for arriving at the claimed compounds stems from the fact that they fall within the generic class of hydrophilic pro-drugs disclosed by Tsubusaki. Accordingly, one having ordinary skill in the art would have been motivated to prepare any of the compounds embraced by the disclosed generic formula, including those encompassed by the claims.
Regarding claim 3, Tusbusaki discloses a method of making their compounds, starting with 3-hydroxybenzaldehyde (reading on an aromatic ketone derivative having a hydroxy group). Tsubusaki discloses: i) forming acetal 38 below under acidic conditions (reading on the dialkyl ketal formation under acidic conditions step); ii) coupling 38 with a phenol having a hydroxymethyl to form 39; iii) coupling 39 with 41 to obtain 42 (reading on coupling with polyoxyethylene derivative, wherein a terminal hydroxy has been removed); iv) then, introducing a ‘leaving group structure -OC(O)E1’ to obtain compounds 43-44 shown above (see [0123]-[0199]).
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While the instant claims require a ketone instead of the aldehyde disclosed by Tsubusaki, Tsubusaki teaches their general structures 3-4 above, wherein R10 (corresponding to instant R6) can be methyl – reading on ketals, which would require a ketone starting material. Acetals and ketals are well known in the art, thus, one of ordinary skill in the art would understand the similar reactivities of aldehydes and ketones and would have a reasonable expectation of success in changing one for the other in Tsubusaki’s method of preparing their compounds to arrive at the desired acetal or ketal (see, for example Dong’s report).1
Regarding the claimed order of steps, which require coupling with polyoxyethylene prior to formation of the ketal (while Tsubusaki teaches formation of the ketal first, and coupling with polyoxyethylene in the third step), Applicant is advised that the courts have held that any order of performing process steps is prima facie obvious in the absence of new or unexpected results (In re Gibson, 39 F.2d 975, 5 USPQ 230 (CCPA 1930); Ex Parte Rubin, 128 USPQ 440 (Bd. App. 1959)). See MPEP § 2144.04 IV C. Therefore, the claimed order of steps is an obvious variant of the steps of the cited prior art.
Regarding claim 4, Tsubusaki teaches their conjugates like 20, wherein P1 can be formula 8, wherein Z3 can be a bond and X1 can be group g below (-NH-Boc group) – reading on deprotecting an amino group protected by a protecting group in P1 of the dialkyl ketal structure (see Tsubusaki’s claims 5 and 10, for instance). Tsubusaki discloses their compounds may be used to link drugs to antibodies (to obtain prodrugs known in the art as ADC – antibody-drug conjugates), specifically teaching that X1 in P1 is to be connected to an antibody, which can ‘react with a functional biomolecule.’ (see [0092]-[0094]) – reading on introducing a functional group capable of reacting with a functional biomolecule.
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Therefore, it would have been prima facie obvious to one of ordinary skill prior to the effective filing date of the claimed invention to prepare the instant ketal-type releasable polyoxyethylene compounds and prodrugs (ADCs) thereof in view of Tsubusaki. One of ordinary skill would have been motivated to do so because Tsubusaki teaches the chemical modification of biofunctional molecule or drug carrier with a hydrophilic polymer having low antigenicity has an advantage, for example, improvement in water solubility of these drugs and the like, avoidance of kidney clearance or suppression of degradation by a metabolic enzyme, and is an effective technique for prolonging circulation time of the drug or the like in blood and for increasing bioavailability (see [0002]). One of ordinary skill would have had a reasonable expectation of success in view of Tsubusaki’s disclosures above. Regarding the order of steps claimed, Applicant is reminded the courts have held that any order of performing process steps is prima facie obvious in the absence of new or unexpected results.
For the purposes of compact prosecution, the alleged unexpected results presented by Applicant in Figure 1 and the specification will be discussed herein:
Applicant compares the compounds 27, 32, and 37 below (starting on page 38 of the spec.). Applicant discloses half-life values of 7.5 days, 3.6 days, and 231 days, respectively (page 45).
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Contrary to Applicant’s conclusion, these values are entirely expected, and one of ordinary skill would have been able to predict these results with minimal, or no experimentation whatsoever. Thayumanavan et al.2 will be cited herein for the sake of argument.
Thayumanavan teaches among pH-sensitive linkers, acetals and ketals have attracted significant attention, because they yield charge-neutral and potentially non-toxic by products upon cleavage (page 2, para. 3). Thayumanavan discloses the following relative half-lives for different benzylic acetals with different patterns of electron-donating group substitution (Fig. 9). As we can see, a compound with ortho, para-electron donating group substituents relative to the acetal/ ketal in Thayumanavan’s compound 16-17 (comparable to instant compound 32) had a much shorter half-life when compared to the acetal with para-electron donating group substitution, like Thayumanavan’s compound 15 (comparable to instant compound 27), which in turn had a much shorter half-life when compared to the double-meta-substituted 18 (comparable to what is observed with instant compound 27). Thus, without even looking at the fact that instant compound 27 is an acetal and instant compounds 32 and 37 are ketals, and in view of Thayumanavan’s disclosure, one of ordinary skill would be easily able to predict the following trend for the half-life of the compounds 27, 32, and 37: 32 < 27 << 37 – which is exactly the trend observed in Figure 1 of the instant disclosure. Thus, the results presented by applicant are not surprising or unexpected at all. In fact, they are entirely expected.
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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 1-2 are rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1-14 of U.S. Patent No. 11,319,408 B2 (US ‘408). Although the claims at issue are not identical, they are not patentably distinct from each other.
Regarding instant claims 1-2, US ‘408 claims the hydrophilic polymer derivatives 3-4 below, which anticipate the instant claims when R2-7 are each independently a hydrocarbon group having from 1 to 10 carbon atoms or a hydrogen atom; R10 is a hydrocarbon; R8-9 are each independently a hydrocarbon group having from 1 to 9 carbon atoms or a hydrogen atom; A1 can be a phenylene group; Z1 can be a bond; B1 is H; E1 is a leaving group; m can be 0 or 1 (US ‘408’s claims 1-2).
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Claims 3-5 are rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1-14 of U.S. Patent No. 11,319,408 B2 (US ‘408); as applied to claims 1-2; in view of Tsubusaki et al. (US 2020/0010620 A1 – Pub. Date: Jan. 9th, 2020 – cited in IDS) (“Tsubusaki”).
The teachings of US ‘408 are disclosed above and incorporated herein.
While US ‘408 doesn’t specifically claim: i) methods of making their hydrophilic polymer derivatives (claims 3-4); or ii) a conjugate of their ketal-type releasable hydrophilic polymer derivatives (claim 5); the teachings of Tsubusaki are relied upon for these disclosures.
Tsubusaki teaches the conjugate compounds of formula 20, which degrade depending on the pH to release a drug ([0051]; see also page 10), wherein the groups are defined as above for formulae 3-4. Tsubusaki’s compounds read on the instant claims when m = 0 and D1 ‘represents a residue obtained by removing an amino group, that constitutes a carbamate bond, from an amino group contained in a functional biomolecule’.
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Therefore, regarding instant claim 5, it would have been prima facie obvious to one of ordinary skill to prepare the instant conjugate compounds from US ‘408’s hydrophilic polymer derivatives in view of Tsubusaki. One of ordinary skill would have been motivated to do so with a reasonable expectation of success because US ‘408’s discloses their hydrophilic polymer derivatives 3-4 and Tsubusaki discloses the same hydrophilic polymer derivatives and their use in the preparation of ADC.
Regarding instant claim 3, Tusbusaki further discloses a method of making US ‘408's compounds, starting with 3-hydroxybenzaldehyde (reading on an aromatic ketone derivative having a hydroxy group). Tsubusaki discloses: i) forming acetal 38 below under acidic conditions (reading on the dialkyl ketal formation under acidic conditions step); ii) coupling 38 with a phenol having a hydroxymethyl to form 39; iii) coupling 39 with 41 to obtain 42 (reading on coupling with polyoxyethylene derivative, wherein a terminal hydroxy has been removed); iv) then, introducing a ‘leaving group structure -OC(O)E1’ to obtain compounds 43-44 shown above (see [0123]-[0199]).
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While the instant claims require a ketone instead of the aldehyde disclosed by Tsubusaki, US ‘408 claims their compounds 3-4, and Tsubusaki teaches their general structures 3-4 above, wherein R10 (corresponding to instant R6) can be methyl – reading on ketals, which would require a ketone starting material. Acetals and ketals are well known in the art, thus, one of ordinary skill in the art would understand the similar reactivities of aldehydes and ketones and would have a reasonable expectation of success in changing one for the other in Tsubusaki’s method of preparing their compounds to arrive at the desired acetal or ketal (see, for example Dong’s report cited above).
Regarding the claimed order of steps, which require coupling with polyoxyethylene prior to formation of the ketal (while Tsubusaki teaches formation of the ketal first, and coupling with polyoxyethylene in the third step), Applicant is advised that the courts have held that any order of performing process steps is prima facie obvious in the absence of new or unexpected results (In re Gibson, 39 F.2d 975, 5 USPQ 230 (CCPA 1930); Ex Parte Rubin, 128 USPQ 440 (Bd. App. 1959)). See MPEP § 2144.04 IV C. Therefore, the claimed order of steps is an obvious variant of the steps of the cited prior art.
Regarding claim 4, Tsubusaki teaches their conjugates like 20, wherein P1 can be formula 8, wherein Z3 can be a bond and X1 can be group g below (-NH-Boc group) – reading on deprotecting an amino group protected by a protecting group in P1 of the dialkyl ketal structure (see Tsubusaki’s claims 5 and 10, for instance). Tsubusaki discloses their compounds may be used to link drugs to antibodies (to obtain prodrugs known in the art as ADC – antibody-drug conjugates), specifically teaching that X1 in P1 is to be connected to an antibody, which can ‘react with a functional biomolecule.’ (see [0092]-[0094]) – reading on introducing a functional group capable of reacting with a functional biomolecule.
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Therefore, it would have been prima facie obvious to one of ordinary skill prior to the effective filing date of the claimed invention to prepare the instant ketal-type releasable polyoxyethylene compounds and prodrugs (ADCs) thereof in view of US ‘408 and Tsubusaki. One of ordinary skill would have been motivated to do so because US ‘408 claims their hydrophilic polymer derivatives; and Tsubusaki teaches the chemical modification of biofunctional molecule or drug carrier with a hydrophilic polymer having low antigenicity has an advantage, for example, improvement in water solubility of these drugs and the like, avoidance of kidney clearance or suppression of degradation by a metabolic enzyme, and is an effective technique for prolonging circulation time of the drug or the like in blood and for increasing bioavailability (see [0002]). One of ordinary skill would have had a reasonable expectation of success in view of Tsubusaki’s disclosures above. Regarding the order of steps claimed, Applicant is reminded the courts have held that any order of performing process steps is prima facie obvious in the absence of new or unexpected results.
Claims 1-5 are provisionally rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1-8 of copending Application No. 18/859,066 (Co. ‘066). Although the claims at issue are not identical, they are not patentably distinct from each other.
Regarding instant claims 1-2, Co. ‘066 claims acetal-type releasable polyoxyethylene derivatives, which differ from the instant compounds only in the fact that their compounds require a H in the position corresponding to instant R6, which has to be a hydrocarbon in the instant claims (Co. ‘066’s claims 1-2). Applicant is advised that H vs. Me is considered an obvious modification in the absence of superior, unexpected results. Note MPEP 2144.09.
Regarding instant claims 3-4, Co. ‘066 claims methods of making their acetals which differ from the instant methods only in the fact that Co. ‘066 employs an aldehyde while the instant claims require a ketone. A person of ordinary skill would have had a reasonable expectation of success making this determination based on whether their intended goal is to prepare an acetal or a ketal (Co. ‘066’s claims 3-4).
Regarding instant claim 5, Co. ‘066 claims a conjugate (Co. ‘066’s claim 5)
This is a provisional nonstatutory double patenting rejection because the patentably indistinct claims have not in fact been patented.
Claims 1-5 are provisionally rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1-10 of copending Application No. 19/528,724 (Co. ‘724); in view of Meanwell et al. (J. Med. Chem. 2011, 54, 2529–2591) (“Meanwell”).
Regarding instant claims 1-2, Co. ‘724 claims their amino-containing ketal-type releasable polyoxyethylene derivatives (Co ‘724’s claims 1-4).
Regarding instant claims 3-4, Co. ‘724 claims methods of making their compounds comprising similar steps are the instant claims, starting from the corresponding amino-containing ketone (Co ‘724’s claims 5-6), Applicant is reminded that the courts have held that any order of performing process steps is prima facie obvious in the absence of new or unexpected results.
Regarding instant claim 5, Co. ‘724 claims the conjugate corresponding to their compounds (Co ‘724’s claim 9).
While Co. ‘724’s compounds have amino-substitution on the phenyl alpha to the ketal and the instant compounds have ethers/ oxy-groups; the teachings on Meanwell are relied upon to leverage these differences.
Meanwell teaches that the design of bioisosteres frequently introduces structural changes that can be beneficial depending on the context, with size, shape, electronic distribution, polarizability, dipole, polarity, lipophilicity, and pKa potentially playing key contributing roles in molecular recognition and mimicry. In the contemporary practice of medicinal chemistry, the development and application of bioisosteres have been adopted as a fundamental tactical approach useful to address a number of aspects associated with the design and development of drug candidates (abstract). Meanwell teaches -N- and -O- as classical, divalent bioisosteres.
Therefore, one having ordinary skill in the art would have found the claimed compounds prima facie obvious, since they are generically embraced by Co. ‘724’s disclosed formula in view of Meanwell. The requisite motivation for arriving at the claimed compounds stems from the fact that they fall within the generic class of amino-containing ketal-type releasable polyoxyethylene derivatives for the preparation of ADC’s disclosed by Co. ‘724, in view of Meanwell’s disclosure that -N- vs -O- are classical divalent bioisosteres. Accordingly, one having ordinary skill in the art would have been motivated to prepare any of the compounds embraced by the disclosed generic formula by replacing the -N- in Co. ‘724’s compounds for -O- to arrive at the instant invention, in view of Meanwell.
This is a provisional nonstatutory double patenting rejection.
Conclusion
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/JACKSON J HERNANDEZ/Examiner, Art Unit 1627
/SARAH PIHONAK/Primary Examiner, Art Unit 1627
1 Dong et al.; A Simple and Versatile Method for the Formation of Acetals/Ketals Using Trace Conventional Acids; ACS Omega (2018) 3 (5): 4974–4985.
2 Thayumanavan et al.; Substituent Effects on the pH Sensitivity of Acetals and Ketals and Their Correlation with Encapsulation Stability in Polymeric Nanogels; Journal American Chemical Society (2017) 139 (6): 2306–2317.
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