DETAILED ACTION
Claims 1-20 are pending.
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 03/13/2026 has been entered.
Status of Claims
Claims 1-20 are pending. Claims 8-13 and 15 have been withdrawn. Claim 1 has been amended.
Claims 1-7, 14, and 16-20 are under examination.
Withdrawn Claim Objections and/or Rejections
The arguments filed on 02/19/2026 have been considered by the examiner.
The rejection of claims 1, 4, 6-7, and 16-18 under 35 USC 103 as being unpatentable over Ye and Blanc et al., as set forth on pp. 2-5 of the previous office action (mailed on 12/30/2025) has been withdrawn in view of the amendments.
The rejection of claims 2-3, 5, and 14 under 35 USC 103 as being unpatentable over Ye, Blanc, and Spetzler et al., as set forth on pp. 5-9 of the previous office action (mailed on 12/30/2025) has been withdrawn in view of the amendments.
The rejection of claim 20 under 35 USC 103 as being unpatentable over Ye, Blanc, Spetzler, and Lee et al., as set forth on pp. 9-10 of the previous office action (mailed on 12/30/2025) has been withdrawn in view of the amendments.
Claim Rejections - 35 USC § 112
The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
The following is a quotation of the first paragraph of pre-AIA 35 U.S.C. 112:
The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention.
Claims 1-7, 14, and 16-20 are rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, because the specification, while being enabling for the claimed method comprising Rab11 positive cells, does not reasonably provide enablement for the claimed method comprising all exosomes. The specification does not enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the invention commensurate in scope with these claims.
Factors to be considered in determining whether a disclosure enables one skilled in the
art to make and use the claimed invention in its full scope without resorting to undue
experimentation include: (1) the quantity of experimentation necessary; (2) the amount of
direction or guidance presented; (3) the presence or absence of working examples; (4) the
nature or complexity of the invention; (5) the state of the prior art; (6) the relative skill of those in
the art; (7) the predictability or unpredictability of the art; and (8) the breadth of the claims. See
In re Wands, 8 USPQ2d. 1400 (Fed. Cir. 1988).
Breadth of the claims
Regarding claims 1-7, 14, and 16-20, the claims recite a method for producing an exosome enriched fraction by using a binding agent to capture any exosome. The breadth of the claims is drawn to a method of capturing any exosome, even those that don’t contain RAB11 and/or RAB4 on the surface. However, not all exosomes contain RAB11 and/or RAB4 on the surface.
Nature or complexity of invention and the level of ordinary skill
The nature of this invention is complex and unpredictable, involving the effects of exosomes, and it would require undue experimentation for the full scope of the invention. Based on the complexity and unpredictability of exosomal enrichment, the level of a person having ordinary skill in the art is not high enough to determine all the exosomes that contain RAB11 and/or RAB4 on the surface, and which exosomes do not contain RAB11 and/or RAB4 on the surface. It is unknown which exosomes contain RAB11 and/or RAB4 on the surface. One of ordinary skill in the art would require undue experimentation in order to determine which exosomes contain RAB11 and/or RAB4 on the surface. In order to practice the full scope of the invention claimed, undue experimentation would be required to determined which exosomes contain RAB11 and/or RAB4 on the surface.
Presence or absence of working examples
The specification teaches that certain exosomes contain RAB11 and/or RAB4 on the surface and are deemed RAB11 positive and/or RAB4 positives exosomes (see page 8). The specification provides one example of a RAB11 positive exosome, K562 (see page 2). However, not all exosomes are RAB11 and/or RAB4 positive, therefore the claims are not enabled for capturing all exosomes. The specification does not enable any person skilled in the art to which it pertains, or with which it is most connected, to use the invention commensurate in scope with these claims. The specification offers insufficient guidance and does not appear to enable all subtypes of exosomes.
State of the Prior Art
The state of the prior art for exosomes is low in exosomes with RAB11, the art does not teach which exosomes have RAB11 on the surface. For example,
Fan et al., “Glutamine deprivation alters the origin and function of cancer cell exosomes.” The EMBO journal vol. 39,16 (2020): e103009. doi:10.15252/embj.2019103009 teaches that Rab11 is not a universal marker on all exosomes (see pages 2 and 4 teaching that specific exosome subtypes have Rab11 on the surface). Therefore, state of prior art for exosomal enrichment was unpredictable before the effective filing date of the invention.
Due to the large quantity of experimentation necessary to determine which exosomes contain RAB11 and/or RAB4 on the surface, the lack of direction/guidance presented in the specification, the absence of working examples, the complex nature of the invention, and the breath of the claims, undue experimentation would be required of the skilled artisan to make and/or use the claimed invention in its full scope.
In an effort to overcome this rejection, it is recommended to amend the claims to recite “a method for producing an RAB11 positive exosome enriched fraction from a sample”.
Conclusion
No claim is allowed.
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Ye et al., (WO2019099955A1) (IDS filed on 10/13/2022) teaches a method for producing an exosome enriched fraction from a sample, the method comprising the steps of i) contacting a first binding agent that specifically binds to the extra-vesicular part of Rab family proteins with the sample under conditions allowing binding of said first binding agent and/or second binding agent to exosomes; and ii) separating exosomes to which the first binding agent and/or the second binding agent is bound from the sample.
Ye does not teach or suggest contacting a first binding agent that specifically binds to the extra-vesicular part of Rab 11 and optionally a second binding agent that specifically binds to the extra-vesicular part of Rab4, nor wherein the extra-vesicular part of Rab11 and optionally Rab4 is present on the exosomal membrane.
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/MCKENZIE A DUNN/Examiner, Art Unit 1678
/GREGORY S EMCH/ Supervisory Patent Examiner, Art Unit 1678
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