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 .
Claim Status
Applicant’s amendments and remarks, filed 06/24/2026, are acknowledged.
Claims 2-5, 7-9, and 15-34 are canceled.
Claims 35-43 are new.
Claims 1, 6, 10-14, and 35-43 are pending.
As such, claims 1, 6, 10-14, and 35-43 are pending examination and currently under consideration for patentability under 37 CFR 1.104.
DETAILED ACTION
Maintained Rejections
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, 6, 10-14, and 35-43 are rejected under 35 U.S.C. 103 as being unpatentable over Srinivasan et al (PLoS Med 15(1): e1002497 (2018); previously submitted with the Office Action mailed 02/10/2025), and further in view of Chakrabarti et al (PLoS ONE 10(6): e0129237(2015); previously submitted with the Office Action mailed 02/10/2025), Wyce et al (PLoS ONE 8(8): e72967 (2013); previously submitted with the Office Action mailed 02/10/2025), Nallasamy et al (Seminars in Cancer Biology 52 (2018) 53–65), Melaiu et al (Clin Cancer Res 2017; 23(15); 4462–72), Kelley et al (JPET Fast Forward. Published on September 8, 2016 as DOI: 10.1124/jpet.116.235283), and Merchant et al (Clin Cancer Res 2015; 22(6); 1364–70).
In regard to instant claims 1, 10, 12, 14, 38, and 40, Srinivasan et al disclose of PD-L1 checkpoint inhibition and anti-CTLA-4 whole tumor cell vaccination counter adaptive immune resistance in a mouse neuroblastoma model (see Title). Adaptive immune resistance induces an immunosuppressive tumor environment that enables immune evasion which results in tumor escape with progression and metastasis (see Abstract). Srinivasan et al disclose of a potent vaccine strategy in a mouse neuroblastoma model (see pg. 4). Srinivasan et al disclose of neuro2a cell lines (N2a) derived from AJ mice and the aggressive subclone of Neuro2a (AgN2a) cells were produced by repeated in vivo passaging of the cells (see pg. 4). The cells were transduced with Id2-shRNA expressing lentiviral particles containing a Puromycin resistance gene (see pg. 4). These cells, also referred to as Id2-kd N2a cells, were injected into the mice models (see pg. 5). An anti-PD-L1 antibody and an anti-CTLA-4 antibody was also administered intra-peritoneally (see pg. 5). The tumors were excised either when they reached 10 mm or when they started to shrink following vaccine therapy (see pg. 5). Srinivasan et al disclose that PD-L1 is detected on the mouse N2a cell line, and its surface expression levels increase in a dose-dependent manner after 24 hours of stimulation with IFNγ (see pg. 7). Similarly, the expression of PD-L1 rises markedly in response to increasing doses of IFNγ in the SK-NSH and SH-SY5Y human cell lines (non-MYCN amplified cell lines) (see Fig. 1A). Srinivasan et al disclose that tumor necrosis was most prevalent in the group that recited Id2kd vaccine plus anti-CTLA-4 antibody, which also displayed the highest level of T-cell infiltrates compared to mice from the other cohorts indicating that the combination of immune priming (Id2kd-N2a vaccine) with immune modulation (anti-CTLA-4 antibody) potently boosts T-cell immunity (see pg. 7). Srinivasan et al found a dramatic increase in PD-L1 expression around tumor-infiltrating lymphocytes in the mouse tumors following Id2kd plus anti-CTLA-4 treatment (see pg. 7). Blockade of both CTLA-4 and PD-L1 might lead to improved immunotherapy by virtue of their differential targets on T-cell expansion and adaptive tumor cell resistance, respectively (see pg. 9). When the vaccine was combined with both CTLA-4 and PD-L1 inhibition, all mice were cured of their tumors and remained tumor free for 6 months in follow-up (see pg. 10 and Figs. 2B-2D). Average tumor growth curves also showed significant differences for treatment when the combination of vaccine with anti-PD-L1 and anti-CTLA-4 was compared to control (see Fig. 2D).
Further, Srinivasan et al disclose that targeting PD-L1 enhanced the effectiveness of whole tumor cell vaccination when combined with CTLA-4 blockade (see pg. 13). There is evidence in the literature suggesting that PD1 inhibition may be more effective than anti-CTLA-4 therapy, but their model and observations suggest that his may only be true for immunogenic tumors in which tumor-infiltrating T cells are already present but rendered incompetent through inhibition of the PD1/PD-L1 pathway (see pgs. 13-14). Srinivasan et al disclose that antibody depletion of CD8+ cells or immune-incompetent mice grow Id2kd tumors avidly, validating the concept that Id2 knockdown confers tumor cell immunogenicity in immune-competent hosts (see pg. 3).
Srinivasan et al fail to disclose of irradiating the cancer cells as recited in claim 13; utilizing an inhibitor of Myc, specifically JQ1 and/or I-BET726, or the PD-L1 and CTLA-4 inhibitors recited in claims 1 and 14. Further, Srinivasan et al fail to disclose of administering an inhibitor of ApoE. This is remedied by Nallasamy, Wyce, Melaiu, Kelley, and Merchant.
While Srinivasan does not explicitly recite administering JQ1 or I-BET726, Melaiu disclose that MYC and MYCN regulate PD-L1 expression in neuroblastoma (see Abstract; pg. 4469). Specifically, Melaiu found that JQ1 treatment significantly reduced PD-L1 surface expression in neuroblastoma cell lines (see pg. 4469; Fig. 5). Further, Wyce et al disclose that BET family proteins are epigenetic regulators known to control expression of genes involved in cell growth and oncogenesis (see Abstract). Selective inhibitors of BET proteins exhibit potent anti-proliferative activity in a number of hematologic cancer models, in part through suppression of the MYC oncogene and downstream Myc-driven pathways (see Abstract). MYC-family transcription factors, including Myc, N-Myc, and L-Myc, are key regulators of cell growth and survival (see pg. 2, left column). Myc plays an important role in hematologic cancers as well as a number of solid tumors, and the MYCN gene is overexpressed in neuroblastoma (see pg. 2, left column). Wyce et al disclose of a selective small molecule inhibitor, I-BET726, that binds to the acetyl-lysine recognition pocket of BET family proteins (see pg. 2, left column; Fig. 1B). I-BET726 is highly selective for BET family proteins, exhibiting no binding affinity for any bromodomain-containing homolog tested with the exception of CREBBP, for which I-BET726 binds with >1000-fold lower affinity than to BET family proteins (see pg. 2 and Figs. 1D, S1). All neuroblastoma cell lines tested exhibited potent growth inhibition, with a median growth IC50 value equal to 75 nM suggesting that neuroblastoma cell lines are particularly sensitive to BET inhibition (see pg. 2, right column). Potent growth inhibition with I-BET726 was observed irrespective of MYCN amplification status, or level of MYC or MYCN expression (see pg. 2, right column). Further, Wyce et al disclose of consistently observing a potent, concentration-dependent decrease in MYCN expression, independent of MYCN amplification status (see pg. 5, right column; Fig. 5A). High concentrations of I-BET726 almost completely silenced MYCN expression in every cell line tested (see pg. 5, right column). Additionally, Wyce disclose of administering I-BET726 once daily at doses of 5 mg/kg or 15 mg/kg in xenograft models of non-MYCN-amplified and MYCN-amplified neuroblastoma in immunocompromised mice (see pg. 8, right column). The xenograft models following treatment with I-BET726 demonstrated a dose-dependent decrease in MYCN and BCL2 expression (see pg. 11, left column). Wyce et al also disclose that their observations of potent BET inhibitor activity in neuroblastoma are consistent with a report using a different BET inhibitor, JQ1, which was similarly shown to inhibit expression of MYCN and downstream n-myc target genes (see pg. 13, left column).
Additionally, Nallasamy disclose that atezolizumab, an anti-PD-L1 antibody, has been evaluated and found successful for neuroblastoma (see Abstract; pg. 56, left col.). Furthermore, Merchant found that ipilimumab treatment stabilized neuroblastoma in a patient (see Table 2; pg. 1367, right col.).
As such, it would have been obvious to combine the teachings of Srinivasan, Melaiu, Nallasamy, and Merchant to develop a method of treating neuroblastoma comprising administering JQ1, atezolizumab, and ipilimumab. One would be motivated to do so because Srinivasan disclose of treating neuroblastoma with Id2-kd N2a cells, an anti-PD-L1 antibody, and an anti-CTLA-4 antibody. Because neuroblastoma cells demonstrate excessively high expression of Id proteins and its function as an effector of n-myc makes it an important target in neuroblastoma (as disclosed by Melaiu), one of skill in the art would have a reasonable expectation that targeting Myc proteins would also provide therapeutic benefit to neuroblastoma cells. This is demonstrated by Wyce who teach that neuroblastoma cells overexpress the MYCN gene, which is associated with Myc, and administering I-BET726 resulted in potent BET family inhibition. Also, one would have a reasonable expectation that administering atezolizumab and ipilimumab, in addition to JQ1 and/or I-BET726, would successfully treat a neuroblastoma patient.
With respect to instant claims 1, 13, 35, 36, and 41-43, Chakrabarti disclose that live attenuated vaccines induce long-lived cellular and humoral immunity, but safety concerns limit their utilization (see pg. 7). Therefore, in lieu of the potential risk of live albeit attenuated Id2-kd N2a tumor cells Chakrabarti et al sought to determine whether irradiation of these cells would dampen the effects of this tumor cell vaccine strategy (see pg. 7). Chakrabarti et al subsequently tested irradiated (35 Gray) Id2-kd N2a cells as a whole tumor cell vaccine antigen source in combination with anti-CTLA-4 antibody against AgN2a (see Fig. 3A) and found that 60% of mice eradicated established tumors (see Fig. 4D). In contrast, irradiated wild type N2a cells administered in a similar combination fashion, had no effect on growth of the AgN2a aggressive tumor cells (see Fig. 4C). This observation again supports the antigenicity of Id2-kd N2a cells for vaccination, but is also encouraging in that irradiation extends the margin of vaccine safety (see pg. 7). Additionally, Chakrabarti et al disclose that irradiation did not demonstrate favorable nor particularly adverse effects on the antigenic properties of the Id2-kd cells in neuroblastoma despite evoking potent anti-tumor immunity in melanoma and lung cancer models (see pg. 7). In the immune-competent mouse model, Id2-kd N2a failed to grow and subsequently developed immunity against further wild-type N2a tumor cell challenge hence making these cells proliferation incompetent (see Abstract and pg. 14).
Lastly, with respect to instant claims 11 and 39, Kelley assessed the anti-tumor effects of APX2009 in neuroblastoma cells (see pg. 5). Kelley found that tumor killing was increased 4.3-8.7-fold when compared to E3330 (APX3330) for the neuroblastoma cell models (see pgs. 16-17).
As such, it would have been obvious to one of ordinary skill in the art at the time of the present invention to administer APX2009 in addition to JQ1/I-BET726, atezolizumab, and ipilimumab to treat neuroblastoma. One would be motivated to do so because the instant situation is amenable to the type of analysis set forth in In re Kerkhoven, 205 USPQ 1069 (CCPA 1980) wherein the court held that it is prima facie obvious to combine two compositions each of which is taught by the prior art to be useful for the very same purpose. The idea of combining them flows logically from having been individually taught in the prior art. Applying the same logic to the instant claims, one of ordinary skill in the art would have been imbued with at least a reasonable expectation of success that by administering JQ1/I-BET726, atezolizumab, and ipilimumab in combination with APX2009 as taught in the references above, one would achieve a method for inhibiting the growth of neuroblastoma cells. The Kerkhoven rationale can also be applied for combined administration of JQ1 and I-BET726 as recited in instant claims 6 and 37; one would have a reasonable expectation that administering JQ1 in combination with I-BET726 would successfully treat neuroblastoma cells as taught by the art.
Applicant’s Arguments
Applicant respectfully disagrees with the Examiner’s position for at least the reasons of record and those set forth below (see pages 7-11 of the Remarks filed 06/24/2026).
At the outset, Applicant notes that the present claims were determined to be free of the prior art in the Official Action dated August 7, 2025. Indeed, the Examiner failed to set forth any prior art rejections on the currently claimed subject matter. Applicant submits that the newly cited references fail to overcome the deficiencies in the teachings of the previously cited references.
At page 5 of the Official Action, the Examiner acknowledges that Srinivasan et al. do not teach irradiating cancer cells prior to administration and do not teach the use of a Myc inhibitor. The Examiner alleges that Melaiu et al. and Wyce et al. overcome this deficiency at pages 6-7 of the Official Action. Applicant respectfully disagrees with the Examiner's position for at least the following reasons. Melaiu et al. never teach or suggest using a Myc inhibitor on a tumor cell vaccine prior to administration to a subject, as required by the present claims. Melaiu et al. also never teach or suggest using a Myc inhibitor in combination with a PD-L1 inhibitor, as required by the present claims. Indeed, if PD-L1 expression is "significantly reduced" as taught by Melaiu et al., why would the skilled artisan then be motivated to administer a PD-L1 inhibitor? Moreover, the presently claimed PD-L1 inhibitors - atezolizumab, avelumab, and durvalumab - are all anti-PD-L1 antibodies. If PD-L1 is already "significantly reduced," then what would the anti-PD-L1 antibodies even bind to or act on? The reference cited by the Examiner is silent and fails to provide the skilled artisan any motivation or expectation of success in using a Myc inhibitor and a PD-L1 inhibitor, particularly an anti-PD-L1 antibody. With regard to Wyce et al., the Examiner asserts at page 6 of the Official Action that the reference teaches that the inhibitor I-BET726 produced "potent growth inhibition" with a neuroblastoma and administration of the inhibitor I-BET726 to a mouse neuroblastoma model resulted in tumor growth inhibition. However, such a disclosure is irrelevant to the instantly claimed invention. The present claims require the neuroblastoma cells be treated with the Myc inhibitor JQ1 or I-BET726 ex vivo - or outside the body. The Myc inhibitor is not administered to the subject as it is in Wyce et al. Indeed, Wyce et al. note that the inhibitor I-BET726 causes "potent growth inhibition," induces cytotoxicity, and shrank tumors in a mouse neuroblastoma model when administered orally (Abstract and page 2). Nothing in Wyce et al. provides the skilled artisan with any motivation or expectation of success to treat cancer cells ex vivo with a Myc inhibitor and then administer those treated cells back into the patient. Indeed, Wyce et al. promotes administration of the inhibitor I-BET726 to the subject with cancer. With regard to Nallasamy et al., the reference has been cited merely for teaching the anti-PD-L1 antibody atezolizumab and that it can be used in neuroblastoma therapies. Nallasamy et al. is silent with regard to Myc inhibition. With regard to Merchant et al., the reference has been cited merely for teaching the anti-CTLA-4 antibody ipilimumab and its effect on neuroblastoma. Merchant et al. is also silent with regard to Myc inhibition. Kelley et al. is cited for allegedly disclosing the anti- tumor effects of APX2009 in neuroblastoma cells. Kelley et al. is silent with regard to Myc inhibition. Chakrabarti et al. disclose that that an attenuated inhibitor of differentiation protein 2-knockdown (Id2-kd) whole neuroblastoma cell vaccine can be effective against neuroblastoma. Chakrabarti et al. are also silent with regard to Myc inhibition. Moreover, while Chakrabarti et al. state that "immunogenicity of the knock-down cells was maintained following irradiation," Chakrabarti et al. also acknowledge that "the mechanism of tumor cell immunogenicity in Id2-kd cells is unknown" and that the effects observed with Id2-kd cells "may or may not be expanded to other cell lines" (page 14).
Response to Arguments
Applicant's arguments filed 06/24/2026 have been fully considered but they are not persuasive.
It is noted that the Official Action dated August 7, 2025 did not indicate that the present claims were determined to be free of the prior art, and that the present action and the action mailed 03/25/2026 have provided prior art rejection(s).
In response to applicant's arguments against the references individually, one cannot show nonobviousness by attacking references individually where the rejections are based on combinations of references. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981); In re Merck & Co., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986). Melaiu et al establish a connection between administering JQ1 with PD-L1 expression in neuroblastoma cells (i.e., a reduction in PD-L1 expression), and Wyce establishes that neuroblastoma cell lines exhibited potent growth inhibition with I-BET726. Examiner agrees that administering an anti-PD-L1 inhibitor would be asinine if JQ1 is administered, but Applicant is reminded that the claims are not limited to administering a PD-L1 inhibitor and includes CTLA-4 inhibitors. Further, Srinivasan et al found a dramatic increase in PD-L1 expression around tumor-infiltrating lymphocytes in the mouse tumors following Id2kd plus anti-CTLA-4 treatment. Thus, blockade of both CTLA-4 and PD-L1 might lead to improved immunotherapy by virtue of their differential targets on T-cell expansion and adaptive tumor cell resistance, respectively, because when the vaccine was combined with both CTLA-4 and PD-L1 inhibition, all mice were cured of their tumors and remained tumor free for 6 months in follow-up. As such, one would choose anti-PD-L1 antibody, atezolizumab, and anti-CTLA-4 antibody ipilimumab as treatment for neuroblastoma because the art (i.e., Nallasamy and Merchant) establish that these treatments are successful treatments for neuroblastoma. Further, administering APX2009 would also provide therapeutic benefit to neuroblastoma patients as taught by Kelley. Furthermore, with respect to irradiating the ex vivo cells, Chakrabarti et al disclose that irradiation did not demonstrate favorable nor particularly adverse effects on the antigenic properties of the Id2-kd cells in neuroblastoma despite evoking potent anti-tumor immunity in melanoma and lung cancer models (see pg. 7); thus, irradiation would be beneficial for melanoma patients.
As such, the 103 rejection is maintained.
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to DANAYA L MIDDLETON whose telephone number is (571)270-5479. The examiner can normally be reached M-F 9:30AM - 6PM with flex.
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/DANAYA L MIDDLETON/Examiner, Art Unit 1674
/VANESSA L. FORD/Supervisory Patent Examiner, Art Unit 1674
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