N-803 Plus BCG Treatment for BCG-Naïve or -Unresponsive Non-Muscle Invasive Bladder Cancer: A Plain Language Review.

WHAT IS THIS SUMMARY ABOUT?: This is a summary of two studies that looked at the safety and effectiveness of a potential new treatment, N-803 (Anktiva), in combination with a standard treatment bacillus Calmette-Guerin (BCG) for people with non-muscle invasive bladder cancer (NMIBC).One study was a Phase 1b study that tested increasing doses of N-803 in combination with the same dose of BCG in people with NMIBC who had never received BCG previously (BCG-naive). The other study is a Phase 2/3 study of N-803 and BCG in people with NMIBC whose cancer wasn't eliminated by BCG alone (BCGunresponsive). WHAT HAPPENED IN THE STUDIES?: In the Phase 1b study, the nine participants were split into three groups of 3 participants who received a dose of 100, 200, or 400 µg N-803 along with a standard 50 mg dose of BCG. In the Phase 2/3 study, one group (cohort A) of participants with carcinoma in situ (CIS) disease and another group (cohort B) with papillary disease were treated with 400 µg N-803 plus 50 mg BCG. There was also a cohort C that received only 400 µg N-803. Treatments were delivered directly into the bladder once a week for 6 weeks in a row. WHAT WERE THE KEY TAKEAWAYS?: N-803 plus BCG eliminated NMIBC in all nine BCG-naive participants and the effects were long-lasting, with participants remaining NMIBC-free for a range of 8.3 to 9.2 years.As reported in 2022, cancer was eliminated in 58 of 82 (71%) participants with BCG-unresponsive CIS disease and the effect was also long-lasting. Importantly, approximately 90% of the successfully treated participants avoided surgical removal of the bladder. In cohort B participants with papillary disease, 40 of 72 (55.4%) were cancer-free 12 months after treatment. N-803 used alone was only effective in 2 of 10 participants. In both studies, the combination of N-803 and BCG was found to be associated with very few adverse events.Based on results from the Phase 2/3 study, the U.S. Food and Drug Association (FDA) approved the use of N-803 plus BCG for the treatment of BCG-unresponsive bladder CIS with or without Ta/T1 papillary disease.Clinical Trial Registration: NCT02138734 (Phase 1b study), NCT03022825 (Phase 2/3 study).

Addition of the IL-15 superagonist N-803 to BCG therapy produces a high rate of success in eliminating non-muscle invasive bladder cancer in both BCG-naive and BCG-unresponsive patients, with long-lasting effects that allow patients to avoid surgical removal of the bladder.

Integrated Multiomics Analysis of Salivary Exosomes to Identify Biomarkers Associated with Changes in Mood States and Fatigue.

Fatigue and other deleterious mood alterations resulting from prolonged efforts such as a long work shift can lead to a decrease in vigilance and cognitive performance, increasing the likelihood of errors during the execution of attention-demanding activities such as piloting an aircraft or performing medical procedures. Thus, a method to rapidly and objectively assess the risk for such cognitive fatigue would be of value. The objective of the study was the identification in saliva-borne exosomes of molecular signals associated with changes in mood and fatigue that may increase the risk of reduced cognitive performance. Using integrated multiomics analysis of exosomes from the saliva of medical residents before and after a 12 h work shift, we observed changes in the abundances of several proteins and miRNAs that were associated with various mood states, and specifically fatigue, as determined by a Profile of Mood States questionnaire. The findings herein point to a promising protein biomarker, phosphoglycerate kinase 1 (PGK1), that was associated with fatigue and displayed changes in abundance in saliva, and we suggest a possible biological mechanism whereby the expression of the PGK1 gene is regulated by miR3185 in response to fatigue. Overall, these data suggest that multiomics analysis of salivary exosomes has merit for identifying novel biomarkers associated with changes in mood states and fatigue. The promising biomarker protein presents an opportunity for the development of a rapid saliva-based test for the assessment of these changes.

Direct Transcriptional Effects of Apolipoprotein E.

A major unanswered question in biology and medicine is the mechanism by which the product of the apolipoprotein E ε4 allele, the lipid-binding protein apolipoprotein E4 (ApoE4), plays a pivotal role in processes as disparate as Alzheimer's disease (AD; in which it is the single most important genetic risk factor), atherosclerotic cardiovascular disease, Lewy body dementia, hominid evolution, and inflammation. Using a combination of neural cell lines, skin fibroblasts from AD patients, and ApoE targeted replacement mouse brains, we show in the present report that ApoE4 undergoes nuclear translocation, binds double-stranded DNA with high affinity (low nanomolar), and functions as a transcription factor. Using chromatin immunoprecipitation and high-throughput DNA sequencing, our results indicate that the ApoE4 DNA binding sites include ∼1700 gene promoter regions. The genes associated with these promoters provide new insight into the mechanism by which AD risk is conferred by ApoE4, because they include genes associated with trophic support, programmed cell death, microtubule disassembly, synaptic function, aging, and insulin resistance, all processes that have been implicated in AD pathogenesis. Significance statement: This study shows for the first time that apolipoprotein E4 binds DNA with high affinity and that its binding sites include 1700 promoter regions that include genes associated with neurotrophins, programmed cell death, synaptic function, sirtuins and aging, and insulin resistance, all processes that have been implicated in Alzheimer's disease pathogenesis.

C-O bond Formation in a Microfluidic Reactor: High Yield SNAr Substitution of Heteroaryl Chlorides.

This study describes our development of a novel and efficient procedure for C-O bond formation under mild conditions, for coupling heteroaryl chlorides with phenols or primary aliphatic alcohols. We utilized a continuous-flow microfluidic reactor for C-O bond formation in electron-deficient pyrimidines and pyridines in a much more facile manner with a cleaner reaction profile, high yield, quick scalability and without the need for the transition metal catalyst. This approach can be of general utility to make C-O bond containing intermediates of industrial importance in a continuous and safe manner.

Quality of Life in the Phase 2/3 Trial of N-803 Plus Bacillus Calmette-Guérin in Bacillus Calmette-Guérin‒Unresponsive Nonmuscle-Invasive Bladder Cancer.

INTRODUCTION: In the phase 2/3 study QUILT-3.032 (NCT03022825), the ability of the IL-15RαFc superagonist N-803 (nogapendekin alfa inbakicept) plus bacillus Calmette-Guérin (BCG) to elicit durable complete responses in patients with BCG-unresponsive nonmuscle-invasive bladder cancer (NMIBC) was demonstrated. As a secondary end point, patient-reported outcomes (PROs) were assessed. METHODS: Both cohort A patients with carcinoma in situ with or without Ta/T1 disease and cohort B patients with high-grade Ta/T1 papillary disease who received N-803 plus BCG therapy completed the EORTC (European Organization for Research and Treatment of Cancer) Core 30 and Quality of Life NMIBC-Specific 24 questionnaires at baseline and months 6, 12, 18, and 24 on study. Scores were analyzed using descriptive statistics, and multivariable analyses were performed to identify baseline variables associated with PROs. RESULTS: On study, mean physical function (PF) and global health (GH) scores remained relatively stable from baseline for cohorts A (n = 86) and B (n = 78). At month 6, cohort A patients with a complete response reported higher PF scores than those without (P = .0659); at month 12, > 3 as compared with ≤ 3 prior transurethral resections of bladder tumor was associated (P = .0729) with lower GH scores. In cohort B, baseline disease type was associated (P = .0738) with PF and race was significantly associated (P = .0478) with GH at month 6. NMIBC-Specific 24 summary scores also remained stable on study for both cohorts. CONCLUSIONS: The overall stability of PROs scores, taken together with the efficacy findings, indicates a favorable risk-benefit ratio and quality of life following N-803 plus BCG.

Inferred Immune-Cell Activity Is an Independent Predictor of HER2-Negative Breast Cancer Prognosis and Response to Paclitaxel-Based Therapy in the GeparSepto Trial.

PURPOSE: Tumor microenvironment (TME) immune markers have been correlated with both response to neoadjuvant therapy and prognosis in patients with breast cancer. Here, immune-cell activity of breast cancer tumors was inferred by expression-based analysis to determine if it is prognostic and/or predictive of response to neoadjuvant paclitaxel-based therapy in the GeparSepto (G7) trial (NCT01583426). EXPERIMENTAL DESIGN: Pre-study biopsies from 279 patients with HER2-negative breast cancer in the G7 trial underwent RNA-seq-based profiling of 104 immune-cell-specific genes to assess inferred Immune Cell Activity (iICA) of 23 immune-cell types. Hierarchical clustering was used to classify tumors as iICA "hot," "warm," or "cold" by comparison of iICA in the G7 cohort relative to that of 1,467 samples from a tumor database established by Nantomics LLC. Correlations between iICA cluster, pathology-assessed tumor-infiltrating lymphocytes (TIL), and hormone receptor (HR) status for pathologic complete response (pCR), disease-free survival (DFS), and overall survival (OS) were determined. RESULTS: iICA cluster correlated with TIL levels. The highest pCR rates were observed in hot cluster tumors, and those with relatively higher TILs. Greater inferred activity of several T-cell types was significantly associated with pCR and survival. DFS and OS were prolonged in patients with hot or warm cluster tumors, the latter particularly for HR negative tumors, even if TILs were relatively low. CONCLUSIONS: Overall, TIL level better predicted pCR, but iICA cluster better predicted survival. Differences in associations between TILs, cluster, pCR, and survival were observed for HR-positive tumors versus HR-negative tumors, suggesting expanded study of the implication of these findings is warranted.

IL-15 Superagonist NAI in BCG-Unresponsive Non-Muscle-Invasive Bladder Cancer.

BACKGROUND: Patients with Bacillus Calmette­Guérin (BCG)­unresponsive non­muscle-invasive bladder cancer (NMIBC) have limited treatment options. The immune cell­activating interleukin-15 (IL-15) superagonist Nogapendekin alfa inbakicept (NAI), also known as N-803, may act synergistically with BCG to elicit durable complete responses (CRs) in this patient population. METHODS: In this open-label, multicenter study, patients with BCG-unresponsive bladder carcinoma in situ (CIS) with or without Ta/T1 papillary disease were treated with intravesical NAI plus BCG (cohort A) or NAI alone (cohort C). Patients with BCG-unresponsive high-grade Ta/T1 papillary NMIBC also received NAI plus BCG (cohort B). The primary end point was the incidence of CR at the 3- or 6-month assessment visit for cohorts A and C, and the disease-free survival (DFS) rate at 12 months for cohort B. Durability, cystectomy avoidance, progression-free survival, disease-specific survival (DSS), and overall survival were secondary end points for cohort A. RESULTS: In cohort A, CR was achieved in 58 (71%) of 82 patients (95% confidence interval [CI]=59.6 to 80.3; median follow-up, 23.9 months), with a median duration of 26.6 months (95% CI=9.9 months to [upper bound not reached]). At 24 months in patients with CR, the Kaplan­Meier estimated probability of avoiding cystectomy and of DSS was 89.2% and 100%, respectively. In cohort B (n=72), the Kaplan­Meier estimated DFS rate was 55.4% (95% CI=42.0% to 66.8%) at 12 months, with median DFS of 19.3 months (95% CI=7.4 months to [upper bound not reached]). Most treatment-emergent adverse events for patients receiving BCG plus NAI were grade 1 to 2 (86%); three grade 3 immune-related treatment-emergent adverse events occurred. CONCLUSIONS: In patients with BCG-unresponsive bladder carcinoma in situ and papillary NMIBC treated with BCG and the novel agent NAI, CRs were achieved with a persistence of effect, cystectomy avoidance, and 100% bladder cancer­specific survival at 24 months. The study is ongoing, with an estimated target enrollment of 200 participants (Funded by ImmunityBio.)

Peptidome Surveillance Across Evolving SARS-CoV-2 Lineages Reveals HLA Binding Conservation in Nucleocapsid Among Variants With Most Potential for T-Cell Epitope Loss in Spike.

To provide a unique global view of the relative potential for evasion of CD8+ and CD4+ T cells by SARS-CoV-2 lineages as they evolve over time, we performed a comprehensive analysis of predicted HLA-I and HLA-II binding peptides in Spike (S) and Nucleocapsid (N) protein sequences of all available SARS-CoV-2 genomes as provided by NIH NCBI at a bi-monthly interval between March and December of 2021. A data supplement of all B.1.1.529 (Omicron) genomes from GISAID in early December was also used to capture the rapidly spreading variant. A key finding is that throughout continued viral evolution and increasing rates of mutations occurring at T-cell epitope hotspots, protein instances with worst-case binding loss did not become the most frequent for any Variant of Concern (VOC) or Variant of Interest (VOI) lineage; suggesting T-cell evasion is not likely to be a dominant evolutionary pressure on SARS-CoV-2. We also determined that throughout the course of the pandemic in 2021, there remained a relatively steady ratio of viral variants that exhibit conservation of epitopes in the N protein, despite significant potential for epitope loss in S relative to other lineages. We further localized conserved regions in N with high epitope yield potential, and illustrated heterogeneity in HLA-I binding across the S protein consistent with empirical observations. Although Omicron's high volume of mutations caused it to exhibit more epitope loss potential than most frequently observed versions of proteins in almost all other VOCs, epitope candidates across its most frequent N proteins were still largely conserved. This analysis adds to the body of evidence suggesting that N may have merit as an additional antigen to elicit immune responses to vaccination with increased potential to provide sustained protection against COVID-19 disease in the face of emerging variants.

Rapid identification of neutralizing antibodies against SARS-CoV-2 variants by mRNA display.

The increasing prevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants with the ability to escape existing humoral protection conferred by previous infection and/or immunization necessitates the discovery of broadly reactive neutralizing antibodies (nAbs). Utilizing mRNA display, we identify a set of antibodies against SARS-CoV-2 spike (S) proteins and characterize the structures of nAbs that recognize epitopes in the S1 subunit of the S glycoprotein. These structural studies reveal distinct binding modes for several antibodies, including the targeting of rare cryptic epitopes in the receptor-binding domain (RBD) of S that interact with angiotensin-converting enzyme 2 (ACE2) to initiate infection, as well as the S1 subdomain 1. Further, we engineer a potent ACE2-blocking nAb to sustain binding to S RBD with the E484K and L452R substitutions found in multiple SARS-CoV-2 variants. We demonstrate that mRNA display is an approach for the rapid identification of nAbs that can be used in combination to combat emerging SARS-CoV-2 variants.

Heterologous saRNA Prime, DNA Dual-Antigen Boost SARS-CoV-2 Vaccination Elicits Robust Cellular Immunogenicity and Cross-Variant Neutralizing Antibodies.

We assessed if immune responses are enhanced in CD-1 mice by heterologous vaccination with two different nucleic acid-based COVID-19 vaccines: a next-generation human adenovirus serotype 5 (hAd5)-vectored dual-antigen spike (S) and nucleocapsid (N) vaccine (AdS+N) and a self-amplifying and -adjuvanted S RNA vaccine (AAHI-SC2) delivered by a nanostructured lipid carrier. The AdS+N vaccine encodes S modified with a fusion motif to increase cell-surface expression and an N antigen modified with an Enhanced T-cell Stimulation Domain (N-ETSD) to direct N to the endosomal/lysosomal compartment and increase MHC class I and II stimulation potential. The S sequence in the AAHI-SC2 vaccine comprises the D614G mutation, two prolines to stabilize S in the prefusion conformation, and 3 glutamines in the furin cleavage region to confer protease resistance. CD-1 mice received vaccination by homologous and heterologous prime > boost combinations. Humoral responses to S were the highest with any regimen that included the AAHI-SC2 vaccine, and IgG bound to wild type and Delta (B.1.617.2) variant S1 at similar levels. An AAHI-SC2 prime followed by an AdS+N boost particularly enhanced CD4+ and CD8+ T-cell responses to both wild type and Delta S peptides relative to all other vaccine regimens. Sera from mice receiving AAHI-SC2 homologous or heterologous vaccination were found to be highly neutralizing for all pseudovirus strains tested: Wuhan, Beta, Delta, and Omicron strains. The findings here, taken in consideration with the availability of both vaccines in thermostable formulations, support the testing of heterologous vaccination by an AAHI-SC2 > AdS+N regimen in animal models of SARS-CoV-2 infection to assess its potential to provide increased protection against emerging SARS-CoV-2 variants particularly in regions of the world where the need for cold-chain storage has limited the distribution of other vaccines.

Safety, Feasibility, and Merits of Longitudinal Molecular Testing of Multiple Metastatic Sites to Inform mTNBC Patient Treatment in the Intensive Trial of Omics in Cancer.

PURPOSE: Patients with metastatic triple-negative breast cancer (mTNBC) have poor outcomes. The Intensive Trial of Omics in Cancer (ITOMIC) sought to determine the feasibility and potential efficacy of informing treatment decisions through multiple biopsies of mTNBC deposits longitudinally over time, accompanied by analysis using a distributed network of experts. METHODS: Thirty-one subjects were enrolled and 432 postenrollment biopsies performed (clinical and study-directed) of which 332 were study-directed. Molecular profiling included whole-genome sequencing or whole-exome sequencing, cancer-associated gene panel sequencing, RNA-sequencing, and immunohistochemistry. To afford time for analysis, subjects were initially treated with cisplatin (19 subjects), or another treatment they had not received previously. The results were discussed at a multi-institutional ITOMIC Tumor Board, and a report transmitted to the subject's oncologist who arrived at the final treatment decision in conjunction with the subject. Assistance was provided to access treatments that were predicted to be effective. RESULTS: Multiple biopsies in single settings and over time were safe, and comprehensive analysis was feasible. Two subjects were found to have lung cancer, one had carcinoma of unknown primary site, tumor samples from three subjects were estrogen receptor-positive and from two others, human epidermal growth factor receptor 2-positive. Two subjects withdrew. Thirty-four of 112 recommended treatments were accessed using approved drugs, clinical trials, and single-patient investigational new drugs. After excluding the three subjects with nonbreast cancers and the two subjects who withdrew, 22 of 26 subjects (84.6%) received at least one ITOMIC Tumor Board-recommended treatment. CONCLUSION: Further exploration of this approach in patients with mTNBC is merited.

A gamma-secretase inhibitor and quinacrine reduce prions and prevent dendritic degeneration in murine brains.

In prion-infected mice, both the Notch-1 intracellular domain transcription factor (NICD) and the disease-causing prion protein (PrP(Sc)) increase in the brain preceding dendritic atrophy and loss. Because the drug LY411575 inhibits the gamma-secretase-catalyzed cleavage of Notch-1 that produces NICD, we asked whether this gamma-secretase inhibitor (GSI) might prevent dendritic degeneration in mice with scrapie. At 50 d postinoculation with Rocky Mountain Laboratory (RML) prions, mice were given GSI orally for 43-60 d. Because we did not expect GSI to produce a reduction of PrP(Sc) levels in brain, we added quinacrine (Qa) to the treatment regimen. Qa inhibits PrP(Sc) formation in cultured cells. The combination of GSI and Qa reduced PrP(Sc) by approximately 95% in the neocortex and hippocampus but only approximately 50% in the thalamus at the site of prion inoculation. The GSI plus Qa combination prevented dendritic atrophy and loss, but GSI alone did not. Even though GSI reduced NICD levels to a greater extent than GSI plus Qa, it was unable to prevent dendritic degeneration. Whether a balance between NICD and dendrite growth-stimulating factors was achieved with GSI plus Qa but not GSI alone remains to be determined. Although the combination of GSI and Qa diminished PrP(Sc) in the brains of RML-infected mice, GSI toxicity prevented us from being able to assess the effect the GSI plus Qa combination on incubation times. Whether less toxic GSIs can be used in place of LY411575 to prolong survival remains to be determined.

Pharmacological inhibition of nSMase2 reduces brain exosome release and α-synuclein pathology in a Parkinson's disease model.

AIM: We have previously reported that cambinol (DDL-112), a known inhibitor of neutral sphingomyelinase-2 (nSMase2), suppressed extracellular vesicle (EV)/exosome production in vitro in a cell model and reduced tau seed propagation. The enzyme nSMase2 is involved in the production of exosomes carrying proteopathic seeds and could contribute to cell-to-cell transmission of pathological protein aggregates implicated in neurodegenerative diseases such as Parkinson's disease (PD). Here, we performed in vivo studies to determine if DDL-112 can reduce brain EV/exosome production and proteopathic alpha synuclein (αSyn) spread in a PD mouse model. METHODS: The acute effects of single-dose treatment with DDL-112 on interleukin-1ß-induced extracellular vesicle (EV) release in brain tissue of Thy1-αSyn PD model mice and chronic effects of 5 week DDL-112 treatment on behavioral/motor function and proteinase K-resistant αSyn aggregates in the PD model were determined. RESULTS/DISCUSSION: In the acute study, pre-treatment with DDL-112 reduced EV/exosome biogenesis and in the chronic study, treatment with DDL-112 was associated with a reduction in αSyn aggregates in the substantia nigra and improvement in motor function. Inhibition of nSMase2 thus offers a new approach to therapeutic development for neurodegenerative diseases with the potential to reduce the spread of disease-specific proteopathic proteins.

An ACE2 Triple Decoy that neutralizes SARS-CoV-2 shows enhanced affinity for virus variants.

The SARS-CoV-2 variants replacing the first wave strain pose an increased threat by their potential ability to escape pre-existing humoral protection. An angiotensin converting enzyme 2 (ACE2) decoy that competes with endogenous ACE2 for binding of the SARS-CoV-2 spike receptor binding domain (S RBD) and inhibits infection may offer a therapeutic option with sustained efficacy against variants. Here, we used Molecular Dynamics (MD) simulation to predict ACE2 sequence substitutions that might increase its affinity for S RBD and screened candidate ACE2 decoys in vitro. The lead ACE2(T27Y/H34A)-IgG1FC fusion protein with enhanced S RBD affinity shows greater live SARS-CoV-2 virus neutralization capability than wild type ACE2. MD simulation was used to predict the effects of S RBD variant mutations on decoy affinity that was then confirmed by testing of an ACE2 Triple Decoy that included an additional enzyme activity-deactivating H374N substitution against mutated S RBD. The ACE2 Triple Decoy maintains high affinity for mutated S RBD, displays enhanced affinity for S RBD N501Y or L452R, and has the highest affinity for S RBD with both E484K and N501Y mutations, making it a viable therapeutic option for the prevention or treatment of SARS-CoV-2 infection with a high likelihood of efficacy against variants.

Graphene nanoplatelet and graphene oxide functionalization of face mask materials inhibits infectivity of trapped SARS-CoV-2.

Recent advancements in bidimensional nanoparticles production such as graphene (G) and graphene oxide (GO) have the potential to meet the need for highly functional personal protective equipment (PPE) against SARS-CoV-2 infection. The ability of G and GO to interact with microorganisms provides an opportunity to develop engineered textiles for use in PPE and limit the spread of COVID-19. PPE in current use in high-risk settings for COVID transmission provides only a physical barrier that decreases infection likelihood and does not inactivate the virus. Here, we show that virus pre-incubation with soluble GO inhibits SARS-CoV-2 infection of VERO cells. Furthermore, when G/GO-functionalized polyurethane or cotton was in contact SARS-CoV-2, the infectivity of the fabric was nearly completely inhibited. The findings presented here constitute an important innovative nanomaterial-based strategy to significantly increase PPE efficacy in protection against the SARS-CoV-2 virus that may implement water filtration, air purification, and diagnostics methods.

Rapid Identification of Neutralizing Antibodies against SARS-CoV-2 Variants by mRNA Display.

The increasing prevalence of SARS-CoV-2 variants with the ability to escape existing humoral protection conferred by previous infection and/or immunization necessitates the discovery of broadly-reactive neutralizing antibodies (nAbs). Utilizing mRNA display, we identified a set of antibodies against SARS-CoV-2 spike (S) proteins and characterized the structures of nAbs that recognized epitopes in the S1 subunit of the S glycoprotein. These structural studies revealed distinct binding modes for several antibodies, including targeting of rare cryptic epitopes in the receptor-binding domain (RBD) of S that interacts with angiotensin- converting enzyme 2 (ACE2) to initiate infection, as well as the S1 subdomain 1. A potent ACE2-blocking nAb was further engineered to sustain binding to S RBD with the E484K and L452R substitutions found in multiple SARS-CoV-2 variants. We demonstrate that mRNA display is a promising approach for the rapid identification of nAbs that can be used in combination to combat emerging SARS-CoV-2 variants.

Intranasal plus subcutaneous prime vaccination with a dual antigen COVID-19 vaccine elicits T-cell and antibody responses in mice.

We have developed a COVID-19 vaccine, hAd5 S-Fusion + N-ETSD, that expresses SARS-CoV-2 spike (S) and nucleocapsid (N) proteins with modifications to increase immune responses delivered using a human adenovirus serotype 5 (hAd5) platform. Here, we demonstrate subcutaneous (SC) prime and SC boost vaccination of CD-1 mice with this dual-antigen vaccine elicits T-helper cell 1 (Th1) biased T-cell and humoral responses to both S and N that are greater than those seen with hAd5 S wild type delivering only unmodified S. We then compared SC to intranasal (IN) prime vaccination with SC or IN boosts and show that an IN prime with an IN boost is as effective at generating Th1 biased humoral responses as the other combinations tested, but an SC prime with an IN or SC boost elicits greater T cell responses. Finally, we used a combined SC plus IN (SC + IN) prime with or without a boost and found the SC + IN prime alone to be as effective in generating humoral and T-cell responses as the SC + IN prime with a boost. The finding that SC + IN prime-only delivery has the potential to provide broad immunity-including mucosal immunity-against SARS-CoV-2 supports further testing of this vaccine and delivery approach in animal models of viral challenge.

Identification and validation of expressed HLA-binding breast cancer neoepitopes for potential use in individualized cancer therapy.

BACKGROUND: Therapeutic regimens designed to augment the immunological response of a patient with breast cancer (BC) to tumor tissue are critically informed by tumor mutational burden and the antigenicity of expressed neoepitopes. Herein we describe a neoepitope and cognate neoepitope-reactive T-cell identification and validation program that supports the development of next-generation immunotherapies. METHODS: Using GPS Cancer, NantOmics research, and The Cancer Genome Atlas databases, we developed a novel bioinformatic-based approach which assesses mutational load, neoepitope expression, human leukocyte antigen (HLA)-binding prediction, and in vitro confirmation of T-cell recognition to preferentially identify targetable neoepitopes. This program was validated by application to a BC cell line and confirmed using tumor biopsies from two patients with BC enrolled in the Tumor-Infiltrating Lymphocytes and Genomics (TILGen) study. RESULTS: The antigenicity and HLA-A2 restriction of the BC cell line predicted neoepitopes were determined by reactivity of T cells from HLA-A2-expressing healthy donors. For the TILGen subjects, tumor-infiltrating lymphocytes (TILs) recognized the predicted neoepitopes both as peptides and on retroviral expression in HLA-matched Epstein-Barr virus-lymphoblastoid cell line and BC cell line MCF-7 cells; PCR clonotyping revealed the presence of T cells in the periphery with T-cell receptors for the predicted neoepitopes. These high-avidity immune responses were polyclonal, mutation-specific and restricted to either HLA class I or II. Interestingly, we observed the persistence and expansion of polyclonal T-cell responses following neoadjuvant chemotherapy. CONCLUSIONS: We demonstrate our neoepitope prediction program allows for the successful identification of neoepitopes targeted by TILs in patients with BC, providing a means to identify tumor-specific immunogenic targets for individualized treatment, including vaccines or adoptively transferred cellular therapies.

Dual-Antigen COVID-19 Vaccine Subcutaneous Prime Delivery With Oral Boosts Protects NHP Against SARS-CoV-2 Challenge.

We have developed a dual-antigen COVID-19 vaccine incorporating genes for a modified SARS-CoV-2 spike protein (S-Fusion) and the viral nucleocapsid (N) protein with an Enhanced T-cell Stimulation Domain (N-ETSD) to increase the potential for MHC class II responses. The vaccine antigens are delivered by a human adenovirus serotype 5 platform, hAd5 [E1-, E2b-, E3-], previously demonstrated to be effective in the presence of Ad immunity. Vaccination of rhesus macaques with the hAd5 S-Fusion + N-ETSD vaccine by subcutaneous prime injection followed by two oral boosts elicited neutralizing anti-S IgG and T helper cell 1-biased T-cell responses to both S and N that protected the upper and lower respiratory tracts from high titer (1 x 106 TCID50) SARS-CoV-2 challenge. Notably, viral replication was inhibited within 24 hours of challenge in both lung and nasal passages, becoming undetectable within 7 days post-challenge.

Complete response to avelumab and IL-15 superagonist N-803 with Abraxane in Merkel cell carcinoma: a case study.

Merkel cell carcinoma (MCC) is a rare aggressive form of skin cancer originating in neuroendocrine cells. The antiprogrammed death ligand 1 (PD-L1) monoclonal antibody (mAb) avelumab has been approved for treatment of MCC, but options are limited, should it be ineffective as a monotherapy. Combined therapy with low/moderate dose nab-paclitaxel and an interleukin 15 (IL-15)-based therapeutic such as the IL-15 'superagonist' N-803 may increase response by activation of the immune system. The case of a 71-year-old man diagnosed with MCC who achieved and maintained a complete response (CR) by treatment with the anti-PD-L1 mAb avelumab in combination with IL-15 superagonist N-803 and nab-paclitaxel (Abraxane) is presented. Avelumab treatment alone resulted in a response in a para-aortic lesion, but not the other tumor masses. N-803 was added, followed by nab-paclitaxel; CT showed a decrease in the size of the abdominal mass at 1 month, near resolution at 3 months and CR at 5 months. Abraxane was discontinued after the first CR on CT, and the patient continues on avelumab/N-803 treatment and maintains a CR. Combination of avelumab with low/moderate-dose chemotherapy and an immune enhancer such as N-803 may offer a viable treatment option for MCC patients for whom avelumab therapy alone was not effective.