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.
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 03/06/2026 has been entered.
Priority
Acknowledgment is made of the present application as a proper National Stage (371) entry of PCT Application No. PCT/CN2018/109760, filed 10/11/2018. PCT/CN2018/109760 claims benefit under 35 U.S.C. 119(e) to provisional application No. 62/606,687, filed 10/05/2017.
Status of the Claims
Claims 1-14 are pending, claim 1 is amended; claims 15-25 are canceled. Claims 1-14 are examined below.
Withdrawn Objections/Rejections
The previous rejection of claims 24 and 25 are withdrawn in response to Applicant’s amendments to the claims.
The previous rejection of claims 24 and 25 under 35 U.S.C. 103 are withdrawn in response to Applicant’s amendments to the claims.
Maintained Objections
Drawings
Color photographs and color drawings are not accepted in utility applications unless a petition filed under 37 CFR 1.84(a)(2) is granted. Any such petition must be accompanied by the appropriate fee set forth in 37 CFR 1.17(h), one set of color drawings or color photographs, as appropriate, if submitted via the USPTO patent electronic filing system or three sets of color drawings or color photographs, as appropriate, if not submitted via the via USPTO patent electronic filing system, and, unless already present, an amendment to include the following language as the first paragraph of the brief description of the drawings section of the specification:
The patent or application file contains at least one drawing executed in color. Copies of this patent or patent application publication with color drawing(s) will be provided by the Office upon request and payment of the necessary fee.
Color photographs will be accepted if the conditions for accepting color drawings and black and white photographs have been satisfied. See 37 CFR 1.84(b)(2).
See color drawings submitted on 12/20/2019.
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.
Claim(s) 1-3, 6 and 7 are rejected under 35 U.S.C. 103 as being unpatentable over Wong et al., WO2012/162563 in view of Krauser et al., A perspective on tritium versus carbon-14: ensuring optimal label selection in pharmaceutical research and development, J. Labelled Comp Radiopharm., 56(9-10), (2013), (abstract only).
Independent claim 1, as previously amended (12/31/2024, and still presently), is no longer limited to digital quantification or to measurement at single copy precision (see amended claims 12/31/2024) and is much broader in scope. As such, the present rejection is also made.
See Figure 1 and para [0116]-[0117], Wong et al. teach methods quantifying exosomes in a sample comprising preparing a first composition contacting sample containing plurality of exosomes with a capture bead comprising a bead conjugated to a first binding agent (see magnetic capture beads) and a second binding agent comprising a detectable moiety (a detectable label, labels encompassed by Wong recited at para [0069], which include radioisotope labels). Wong teach separating the capture beads, first complexes and second complexes from the remainder of the first composition (see Wong et al. at para [0116] reciting washing and collecting the mixture at the electrodes by magnetic field, thereby addressing a separation to give a second washed composition collected at the electrodes, detecting detectable signal.
Additionally, although at the Example at Figure 1 and para [0116], Wong relies on label that is an enzyme label, see as cited above, para [0069] Wong disclose appropriate alternative detectable label species including radioisotopes.
Although Wong discloses both enzyme and radiolabels as suitable detectable reagents, the example at Figure 1 does not specifically use a radioisotope label (see is an enzyme label). It would have been further prima obvious to one having ordinary skill in the art to have modified the example at para [0116] of Wong in order to rely on radioisotope label for detection because Wong specifically disclose in addition to enzyme labels, other labels such as radioisotope labels as suitable for their methods. As a result, the modification at the specific example would have been an obvious matter of a simple substitution of one suggested label for another, the results therefore predictable (and one would have a reasonable expectation of success) because Wong specifically disclose each as suitable alternatives of one another for their detection methods.
Wong fails to teach specific species of radioisotope, and as such fails to teach radioisotope label that is 35S or 3H.
Krauser et al. teach that tritium (3H) and carbon-14 (14C) labels in pharmaceutical research and development each off their own distinct advantages and disadvantages coupled with benefits and risks (abstract). See at the abstract, Krauser teach 3H offers the advantages of higher specific activity, shorter half-life that allows more manageable waste remediation, lower material cost, and often more direct synthetic routes.
It would have been prima facie obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to have modified Wong et al., in order to use 3H as the radioisotope label because of its recognized specific advantages, namely higher specific activity and shorter half-life which allows manageable waste remediation, lower coat and more direct synthetic route (Krauser abstract). Further, the selection of 3H is an obvious matter of selecting from a finite list of art recognized suitable radioisotope labels (from 3H and 14C, as disclosed by Krauser, a list of 2), both recognized in the art as labels exhibiting their own specific advantages and disadvantages, both recognized as suitable art recognized radioisotope labels. One having ordinary skill in the art would have a reasonable expectation of success because this radioisotope is considered a suitable art recognized radioisotope label compared to others and because Wong does already teach labels including radioisotopes as suitable label species.
Regarding claim 2, see the contacting steps are performed at paras [0115]-[0116] and encompass first capture bead contact, followed by labeled detector reagent.
Regarding claim 3, see Wong at para [0006], teaching magnetic beads with a diameter of 1-2 µm. In the present case, the prior art range is substantially similar to the claimed range of 4-5 microns. See MPEP 2144.05, a prima facie case of obviousness exists where the claimed ranges or amounts do not overlap with the prior art but are merely close. Titanium Metals Corp. of America v. Banner, 778 F.2d 775, 783, 227 USPQ 773, 779 (Fed. Cir. 1985). The claimed range and the prior art range are extremely close diameters. Given the similarity between the two, one having ordinary skill in the art would not have expected the particles of the prior art to have distinct characteristics as compared those of the claimed diameter. As such, absent evidence of criticality or evidence supporting the prior art disclosed diameter the claimed diameter would have different characteristics, the claimed invention is obvious over the prior art.
Regarding claim 6, see as cited above, Wong addresses binding agents that are antibodies.
Regarding claim 7, Wong teach binding agents specific to species as claimed including CD63, CD9, CD81.
Claim(s) 4 and 5 are rejected under 35 U.S.C. 103 as being unpatentable over Wong et al. in view of Krauser et al., as applied to claim 1 above, and further in view of Hirai et al., US PG Pub No. 2007/0224705A1 (previously cited).
Wong and the cited art teach methods substantially as claimed, however fail to teach bead comprising agarose, an inert polymer, a superparamagnetic material or any combination thereof (claim 4), and fails to teach the bead comprises ferrite or magnetite, optionally coated with polystyrene (claim 5).
Hirai is an example of magnetic particles used for detection which are commercially available, see para [0005], teaching DYNABEADS, polystyrene beads in which ferrite fine particles are dispersed.
It would have been further prima facie obvious to one having ordinary skill in the art before the effective filing date of the claimed invention, to have modified Wong et al. in order to use the DYNABEADS as described in Hirai as an obvious matter of a known material for its art recognized purpose. One having ordinary skill in the art would have had a reasonable expectation of success using a known material for its recognized purpose, and further would expect success because Wong is not limited to any particular magnetic particle species.
Claim(s) 1-8, 10, 12 and 13 are rejected under 35 U.S.C. 103 as being unpatentable over CN105974122A (IDS entered 12/31/2019) in view of Matsumoto et al., Quantification of plasma exosome is a potential prognostic marker for esophageal squamous cell carcinoma, Oncology Reports, 36, (2016), p. 2535-2543, Kunding et al., WO2017/060457 A1, Mian et al., US PG Pub No. 2001/0055812A1 and Krauser et al., Isotope-labeled immunoassays without radiation waste, PNAS, 97(6), (2000), p. 2445-2449., and as evidenced by Hirai et al., US PG Pub No. 2007/0224705A1 (previously cited).
CN105974122A teach a method for the capture and detection of exosomes in a sample, the method comprising contacting sample with a capture bead comprising a bead conjugated to a first binding agent (exosome specific antibody modified immunomagnetic beads, see abstract), and a second binding agent comprising a detectable label (HRP linked via biotin-streptavidin to an anti-GPC1 antibody, see abstract), thereby preparing a first composition as presently claimed. The first binding agent of CN105974122A specifically binds to a first biomolecule present in the plurality of exosomes to produce a first complex (bead, and first exosome), the second binding agent specifically binds to the second biomolecule present in the plurality to produce an exosome-second binding agent-complex comprising the capture bead and the first exosome and the second binding agent (see abstract).
CN105974122A teaches separating the magnetic beads by an external magnetic field (thereby addressing step b, separating as claimed, thereby providing a second composition), and testing with a magnetic-electrochemical sensor (exosome specific antibody such an anti-CD63 as elected by Applicant, see for example page 3 of the machine translation). CN105974122A teach detection as taught (comprising anti-CD-63 and anti-GPC1) is significant to early diagnosis of cancer and its treatment (page 3).
As cited, CN105974122A teaches label that is HRP, as such the reference fails to further teach the second binding agent comprising a detectable label that is a radioisotope, that is 3H.
CN105974122A, as noted previously, also fails to teach, from the second composition, further separating from each other, the capture beads, the first complexes, the second complexes (i.e., a step of further separating the magnetically separated components, individually), prior to detecting signal from the second binding agent present to quantify the exosomes (CN105974122A is silent as to whether they are quantitating, or merely detecting presence).
Matsumoto et al. support that quantification of exosomes is important to cancer diagnostics, for example for diagnostics and for predicting prognosis (abstract, as well as page 2542, col. 1, para 2 and second to last and last paragraphs).
Kunding et al. teach a device and method for the purpose of digitally counting analytes of interest encapsulated in nano-droplets (a droplet based analyte counting system, see abstract), specifically by encapsulating in a droplet, each analyte is separated individually. See page 40, para 5, Kunding’s methods encompass analytes in laboratory-processed samples, meaning analytes may be subject to other laboratory protocols prior to the method of Kunding to prepare the analyte for measurement, see at para 5, analyte may be subjected to microparticle adsorption. Further, see for example page 52, embodiment 70, the method of Kunding can be applied for analytes including for example detection of exosomes. Kunding suggest their method as a way to allow rapid achievement of a detectable concentration for, for example, digital counting of an analyte (page 27, para 4).
Mian et al. is another example of a microfluidic system (para [0003]) which can be applied for flow cytometry, cell counting, sorting as well as cellular biological analysis/testing (para [0192]), further including cells and/or particles comprising analytes (para [0045]). Regarding means of detection on such microfluidic devices, see Mian teach detection systems can be spectroscopic, electrochemical, physical, light scattering, radioactive (paras [0178] and [0208], as well as paras [0288] and [0289]). See para [0262] reported by Mian as an illustrative example, sandwich immunoassay, where second antibody is labeled with a detectable moiety, such as a radiolabel, fluorescent label, enzyme label or catalytic functionality.
Krauser et al. teach that tritium (3H) and carbon-14 (14C) labels in pharmaceutical research and development each off their own distinct advantages and disadvantages coupled with benefits and risks (abstract). See at the abstract, Krauser teach 3H offers the advantages of higher specific activity, shorter half-life that allows more manageable waste remediation, lower material cost, and often more direct synthetic routes. One having ordinary skill in the art at the time that the claimed invention was effectively filed would have been motivated to have further subjected the separated and captured exosomes of CN105974122A to the micro-droplet based sorting and digital counting of Kunding because Kunding teach method as capable of rapidly achieving detectable concentrations of low sample concentration analytes, and further because the art recognized at the time that quantifying exosomes (for example, cancer related exosomes as in CN105974122A) has diagnostic and prognostic advantages (Matsumoto). As such, one would be motivated to further digitally count the detected exosomes (i.e., detect the detectable signal from the second complexes in order to quantify the exosomes in the sample).
Further, considering the prognostic and diagnostic value of cancer related exosomes recognized in the art at the time (Matsumoto), the modification would be considered and obvious matter of applying a known technique to a known method. Specifically, one motivated to apply the technique of Kunding in order to precisely quantitate the exosomes detected in CN105974122A, in order to further assess diagnostic/prognostic predictions. One having ordinary skill further having a reasonable expectation of success given that Kunding teach their techniques applicable for the detection of many types of small analytes, including exosomes.
Further, although CN105974122A and the combined prior art teach enzyme (HRP) labeled antibody, it would have been prima facie obvious to one having ordinary skill in the art at the time the claimed invention was effectively filed to have substituted a radioisotope for the HRP enzyme label as an obvious matter of a simple substitution of one art recognized label for another. In particular, the prior art contained the base method as taught by CN105974122A, which demonstrated the use of two labeled antibodies (a magnetic particle labeled antibody and a detectably labeled antibody) for binding a targeted exosome, the combination of the prior art teaching digitally counting as droplets flow through the microfluidic system. The claimed invention differs in terms of the detectable label, namely the claims teaching radioisotope while CN105974122A is teaching an HRP label. However, each of HRP and radioisotope labeling were art recognized labels known and recognized for labeling antibody for binding and detection of targeted analytes including exosomes, detectable in microfluidic systems (see for example Mian et al.). One having ordinary skill in the art would have found it obvious to have modified CN105974122A, to have substituted the radioisotope label for the HRP label, and the results of the substitution have predictably yielded binding and detection of exosomes, the modification merely encompassing one detection technique/label for another. One having ordinary skill would have had a reasonable expectation of success since both were labels known for detectably labeling an antibody (particularly for use in sandwich immunoassay, see cited above, Mian), and because such detectably labeled antibodies were recognized as usable in microfluidic systems (Mian).
It would have been prima facie obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to have modified CN105974122A and the cited art, in order to use 3H as the radioisotope label because of its art recognized advantages as discussed above, taught by Krauser, and further as an obvious matter to try, namely by selecting from a finite list of known suitable alternatives (see discussed above).
One having ordinary skill in the art would have a reasonable expectation of success because this radioisotope is considered an art recognized suitable radioisotope label known to those of ordinary skill in the art (Krauser).
Regarding claim 2, see the combination of the art cited above.
Regarding claim 3, see CN105974122A teaches a bead diameter of 2.2-3.2 microns (e.g., page 3). In the present case, the prior art range is substantially similar to the claimed range of 4-5 microns. See MPEP 2144.05, a prima facie case of obviousness exists where the claimed ranges or amounts do not overlap with the prior art but are merely close. Titanium Metals Corp. of America v. Banner, 778 F.2d 775, 783, 227 USPQ 773, 779 (Fed. Cir. 1985). The claimed range and the prior art range are extremely close diameters. Given the similarity between the two, one having ordinary skill in the art would not have expected the particles of the prior art to have distinct characteristics as compared those of the claimed diameter. As such, absent evidence of criticality or evidence supporting the prior art disclosed diameter the claimed diameter would have different characteristics, the claimed invention is obvious over the prior art.
Regarding claim 4, see the combination of the cited art above addresses the claim (superparamagnetic material).
Regarding claim 5, CN105974122A is teaching M-270 epoxy resin magnetic bead (i.e., Dynabeads), and as evidenced by Hirai, Dynabeads® are polystyrene beads containing dispersed ferrite (see Hirai para [0005]).
Regarding claim 6, see each of the binding agents as taught by the art (cited above) are independent antibodies.
Regarding claim 7, see as taught above the antibodies binding CD63 and GPC1 (Applicant’s elected species).
Regarding claim 8, see as cited above, the combination of the art teaching separation by droplet generation (droplet-based microfluidics, Kunding).
Regarding claim 10, CN105974122A relies on passive droplet formation (without an external actuation, see no external actuation indicated).
Regarding claim 13, CN105974122A teaches a support comprising microwell structures on the bottom.
Claim(s) 9, 10 and 11 are rejected under 35 U.S.C. 103 as being unpatentable over CN105974122A in view of Matsumoto et al., Kunding et al., Mian et al. and Krauser et al., as applied to claim 8 above, and further in view of Dressler et al., Droplet-Based Microfluidics: Enabling Impact on Drug Discovery, Journal of Biomolecular Screening, 19(4), (2014), p. 483-496.
CN105974122A and the cited art teach a method substantially as claimed (see as indicated above); however, fails to clearly teach if the droplet generation is active (claim 9), or if the droplet generation is passive (claim 10).
Dressler et al. teach there are many methods for droplet generation within chip-based formats reported in the art (see page 485, col. 1, para 2). Compared to active methods, Dressler teach passive methods are most widely used (col. 1, para 2).
It would have been prima facie obvious to one having ordinary skill in the art at the time the claimed invention was effectively filed to have relied on either active generation or the passive generation of droplets, as these are the two art recognized techniques for microfluidic droplet formation, as is taught by Dressler. See Dressler teach there are many known methods, with passive considered the most widely used. One having ordinary skill would have a reasonable expectation of success since both are art recognized techniques that achieve the same purpose, namely predictably yield generated droplets.
Regarding passive droplet generation techniques, one art recognized technique is referred to as “co-flowing”, see for example Dressler, page 486, col. 1, para 1 (referring to the use of two co-flowing solutions to generate droplets). It would have been further obvious to, for example, rely on co-flowing as an obvious matter of applying a known technique to a known method, as one of ordinary skill would have recognized application of the known technique would predictably yield generated droplets (thereby further attributing to a reasonable expectation of success).
Claim(s) 14 is rejected under 35 U.S.C. 103 as being unpatentable over CN105974122A in view of Matsumoto et al., Kunding et al., Mian et al. and Krauser et al., as applied to claim 13 above, and further in view of Duffy et al., Rapid Prototyping of Microfluidic Systems in Poly(dimethylsiloxane), Anal. Chem., 70, (1998), p. 4974-4984.
CN105974122A et al. and the cited art teach a method substantially as claimed (see as indicated above), see as cited above, including separation into micro-wells.
However, the cited art fails to teach a microwell (support) comprising poly(dimethylsiloxane) polymer or glass bottom bonded to a silicon grid that creates the microwells.
Duffy teach regarding microfluidic systems, polymers offer an attractive alternative to glass and Si/SiO2 as material because they are less expensive and less fragile (see page 4975, col. 2, last paragraph). Duffy is teaching a PDMS system (end of col. 2 page 4976). See in particular, page 4982, col. 2, para 2, Duffy teach microfluidic devices fabricated from PDMS are physically robust (can be dropped or bent without damage). See further para 3, Duffy teach two main advantages of using PDMS over other polymers, first is that oxidized PDMS is charged under neutral and basic aqueous solutions, and second is that there are several strategies to control the surface chemistry of oxidized PDMS.
One having ordinary skill would have been motivated to have relied on a support that is PDMS because PDMS is less expensive and less fragile, and as such, microfluidic devices made out of this material are more robust, as well as other advantages (see as discussed above). The modification would be an obvious matter of applying a known material for its art recognized intended purpose. One having ordinary skill would have reasonable expectation of success since PDMS is less fragile and more robust (and considering this material is already recognized as suitable for these types of microfluidic systems).
Response to Arguments
Applicant's arguments filed 01/30/2026 have been fully considered but they are not persuasive for the following reasons.
Regarding the objection to the drawings (remarks page 5), Applicant recognizes the objection, however no petition is submitted. The objection is maintained, as indicated in detail above.
Regarding the rejection of claims 24 and 25 under 35 U.S.C. 101, the previous rejection is withdrawn in response to Applicant’s amendments to the claims (the claim are canceled by Applicant).
Regarding the rejections of claims under 35 U.S.C. 103 (remarks pages 5-6), Applicant refers to the amendments to the claims to omit 14C. In response, the previous rejection citing Shan et al. is withdrawn (see as indicated above), see the new grounds set forth in detail above in response to amendments to the claims.
Further, regarding previously cited Shan et al., Applicant argues Shan et al. teaches away from using either of 35S or 3H, arguing there would be no reason to modify Wong et al. to arrive at the claimed invention.
However, this argument is not persuasive, Shan et al. is no longer relied upon, and further, see newly cited Krauser (in response to amendments to the claims), which provides motivation to rely on either of 14C or 3H when relying on radioisotope labeling. Krauser provides specific motivations for why one of ordinary skill would want to rely on 3H. Additionally, one having ordinary skill would have a reasonable expectation of success considering that Wong suggest radioisotope labels as suitable alternative labels (to their enzyme label) and because 3H is an art recognized radioisotope label known and usable in the art for labeling purposes.
Regarding remarks at pages 6-9, Applicant refers to the same remarks detailed above (see referring to the same specific arguments directed to the combination of Wong and Shan et al., namely that Shan is considered a teaching away from the labels as claimed). This argument is not persuasive for the reasons as addressed in detail above.
Correspondence
Any inquiry concerning this communication or earlier communications from the examiner should be directed to ELLEN J MARCSISIN whose telephone number is (571)272-6001. The examiner can normally be reached M-F 8:00am-4:30pm.
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/ELLEN J MARCSISIN/Primary Examiner, Art Unit 1677