Prosecution Insights
Last updated: April 19, 2026
Application No. 17/615,302

EXTRACELLULAR VESICLES FOR DELIVERING THERAPEUTIC OR DIAGNOSTIC DRUGS

Non-Final OA §103
Filed
Nov 30, 2021
Examiner
CABRAL, ROBERT S
Art Unit
1614
Tech Center
1600 — Biotechnology & Organic Chemistry
Assignee
Fondazione Irccs Istituto Nazionale Dei Tumori
OA Round
3 (Non-Final)
62%
Grant Probability
Moderate
3-4
OA Rounds
3y 4m
To Grant
95%
With Interview

Examiner Intelligence

Grants 62% of resolved cases
62%
Career Allow Rate
531 granted / 852 resolved
+2.3% vs TC avg
Strong +32% interview lift
Without
With
+32.5%
Interview Lift
resolved cases with interview
Typical timeline
3y 4m
Avg Prosecution
24 currently pending
Career history
876
Total Applications
across all art units

Statute-Specific Performance

§101
2.3%
-37.7% vs TC avg
§103
39.8%
-0.2% vs TC avg
§102
23.0%
-17.0% vs TC avg
§112
21.3%
-18.7% vs TC avg
Black line = Tech Center average estimate • Based on career data from 852 resolved cases

Office Action

§103
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 . 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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 1/23/2026 has been entered. Claims 8-10, 14, 15 and 17-24 are pending. Response to Arguments Applicant’s arguments with respect to claim(s) 8-10, 14, 15 and 17-24 have been considered but are moot because the new ground of rejection does not rely on any reference applied in the prior rejection of record for any teaching or matter specifically challenged in the argument. Claim Rejections - 35 USC § 103 The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action: A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made. The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows: 1. Determining the scope and contents of the prior art. 2. Ascertaining the differences between the prior art and the claims at issue. 3. Resolving the level of ordinary skill in the pertinent art. 4. Considering objective evidence present in the application indicating obviousness or nonobviousness. This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention. Claim(s) 8-18 and 20-24 is/are rejected under 35 U.S.C. 103 as being unpatentable over Kalluri (US 2021/0115449) in view of Gingeras et al. (US 2017/0051282). Regarding claim 8, Kalluri teaches “lipid-based nanoparticles, such as exosomes, that comprise a therapeutic agent that activates a tumor suppressor . . . [and] using such compositions to treat a patient having a cancer” (current claim 23). Abstract; see also para. [0061]. “In certain aspects, the lipid-based nanoparticle are exosomes, wherein the exosomes are autologous. In certain aspects, the exosomes are obtained from a body fluid sample obtained from the patient. In certain aspects, the body fluid sample is blood”. Para. [0016]. In particular, with respect to isolating exosome from media Kalluri teaches “centrifuge at room temperature for five minutes at 800xg to pellet dead cells and large debris.” Para. [0055]. This is followed by 10 more minutes of centrifugation at 2000xg. See id. Kalluri also teaches to aspirate the supernatant. See id. This would teach or suggestion the group of steps labeled “A”. Kalluir also teaches that “sequential centrifugations, when combined with sucrose gradient ultracentrifugation can provide high enrichment of exosomes.” Para. [0048]. For example, Kalluir teaches “a second round of ultracentrifugation at 150,000xg at 4 °C for 2 hours.” Para. [0058]. This would teach or suggestion the group of steps labeled “B”. Kalluri does not expressly teach “an isolated sample of blood plasma from an oncological patient.” Gingeras et al. relates to “methods and compositions for treating cancers.” Abstract. In this regard, Gingeras et al. teaches “isolating EVs from a biological sample from a subject.” Para. [0034]. Gingeras et al. further teaches that the best suited sample would be “biological fluids and organs that would be predicted to contain cancer-derived EVs.” Para. [0176]. This implies isolating a sample from a subject with cancer. Furthermore, “the biological sample is blood or a component thereof. In some embodiments, the biological sample comprises milk, blood, serum, plasma, ascites, cyst fluid, pleural fluid, peritoneal fluid, cerebral spinal fluid, tears, urine, saliva, sputum, or combinations thereof.” Id. It would have been prima facie obvious to one of ordinary skill in the art prior to the effective filing date of the invention in view of the combination of Kalluri and Gingeras et al. to arrive at the claimed invention. Indeed, one of ordinary skill in the art would find motivation to combine the references and have a reasonable expectation of success in their combination because both references teach using extracellular vesicle for treating cancer. In re Kerkhoven, 626 F.2d 846, 850, 205 USPQ 1069, 1072 (CCPA 1980) (“It is prima facie obvious to combine two compositions each of which is taught by the prior art to be useful for the same purpose, in order to form a third composition to be used for the very same purpose.... [T]he idea of combining them flows logically from their having been individually taught in the prior art.”) In this instance, the claimed invention is distinguished from Kalluri by indicating a particular population from which the sample is taken. As indicated above, Kalluri already teaches that a blood sample may be isolated from patient. It just does not expressly state that the patient has cancer. However, that a sample may be taken from a patient with cancer is taught by Gingeras et al. as well as the fact that the sample may be plasma. Thus, it would have been within the purview of one of ordinary skill in the art to practice the teachings of Kalluri with patient that had cancer and had a reasonable expectation of success in doing so. Regarding claim 9, “the exosome pellet can be resuspended in PBS,” Id., and filtered. See para. [0058]. Regarding claim 10, Kalluri teaches further purifying after resuspending. See para. [0055]. Regarding claims 14, 15 and 17, Kalluri teaches mixing 1 x 108 exosome and siRINA or shRNA, performing electroporation and treating with protease-free RNAse followed by RNase inhibitor. See paras. [0059] – [0060]. Regarding claim 18, a recitation of the intended use of the claimed invention must result in a structural difference between the claimed invention and the prior art in order to patentably distinguish the claimed invention from the prior art. If the prior art structure is capable of performing the intended use, then it meets the claim. Regarding claim 20, Kalluri teaches paclitaxel. See para. [0088]. Regarding claim 21, a recitation of the intended use of the claimed invention must result in a structural difference between the claimed invention and the prior art in order to patentably distinguish the claimed invention from the prior art. If the prior art structure is capable of performing the intended use, then it meets the claim. Regarding claim 22, Kalluri describes an exosome as “having a diameter . . . of between about 10 nm to about 5000 nm.” Para. [0044]. Also, Kalluir teaches 100 nm liposomes. See para. [0060]. Regarding claim 24, a recitation of the intended use of the claimed invention must result in a structural difference between the claimed invention and the prior art in order to patentably distinguish the claimed invention from the prior art. If the prior art structure is capable of performing the intended use, then it meets the claim. Claim(s) 19 is/are rejected under 35 U.S.C. 103 as being unpatentable over Kalluri (US 2021/0115449) in view of Gingeras et al. (US 2017/0051282) as applied to claims 8-18 and 20-24 above, and further in view of Zheng et al. (US 2021/0212955). Teachings of Kalluri are discussed above. Regarding claim 19, Kalluri does not teach indocyanine green. Zheng et al. teaches extracellular vesicle – MOF- protein (EMP) nanoparticles loaded with indocyanine green. See para. [0236]. It would have been prima facie obvious to one of ordinary skill in the art prior to the effective filing date of the invention to arrive at the claimed invention in view of the combination of Kalluri, Gingeras et al. and Zheng et al. In this regard, it is prima facie obviousness to select a known material based on its suitability for its intended use. See Sinclair & Carroll Co. v. Interchemical Corp., 325 U.S. 327, 65 USPQ 297 (1945). Established precedent holds that it is generally obvious to add known ingredients to known compositions with the expectation of obtaining their known function. See, e.g., In re Linder, 457 F.2d 506, 507 (CCPA 1972); see also In re Dial, 326 F.2d 430,432 (CCPA 1964). It would have been obvious to employ indocyanine green as a fluorescent label as taught by Zheng et al. for Kalluri’s exosome. Conclusion Any inquiry concerning this communication or earlier communications from the examiner should be directed to ROBERT S CABRAL whose telephone number is (571)270-3769. The examiner can normally be reached M-F 8 am - 5 pm. 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, Ali Soroush can be reached at 571-272-9925. 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. /ROBERT S CABRAL/Primary Examiner, Art Unit 1614
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Prosecution Timeline

Nov 30, 2021
Application Filed
Feb 19, 2025
Non-Final Rejection — §103
Jul 17, 2025
Response Filed
Oct 18, 2025
Final Rejection — §103
Jan 23, 2026
Request for Continued Examination
Jan 27, 2026
Response after Non-Final Action
Feb 21, 2026
Non-Final Rejection — §103 (current)

Precedent Cases

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Study what changed to get past this examiner. Based on 5 most recent grants.

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Prosecution Projections

3-4
Expected OA Rounds
62%
Grant Probability
95%
With Interview (+32.5%)
3y 4m
Median Time to Grant
High
PTA Risk
Based on 852 resolved cases by this examiner. Grant probability derived from career allow rate.

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