ResearchPad - immunotherapy https://www.researchpad.co Default RSS Feed en-us © 2020 Newgen KnowledgeWorks <![CDATA[A non-stationary Markov model for economic evaluation of grass pollen allergoid immunotherapy]]> https://www.researchpad.co/article/elastic_article_14555 Allergic rhino-conjunctivitis (ARC) is an IgE-mediated disease that occurs after exposure to indoor or outdoor allergens, or to non-specific triggers. Effective treatment options for seasonal ARC are available, but the economic aspects and burden of these therapies are not of secondary importance, also considered that the prevalence of ARC has been estimated at 23% in Europe. For these reasons, we propose a novel flexible cost-effectiveness analysis (CEA) model, intended to provide healthcare professionals and policymakers with useful information aimed at cost-effective interventions for grass-pollen induced allergic rhino-conjunctivitis (ARC).MethodsTreatments compared are: 1. no AIT, first-line symptomatic drug-therapy with no allergoid immunotherapy (AIT). 2. SCIT, subcutaneous immunotherapy. 3. SLIT, sublingual immunotherapy. The proposed model is a non-stationary Markovian model, that is flexible enough to reflect those treatment-related problems often encountered in real-life and clinical practice, but that cannot be adequately represented in randomized clinical trials (RCTs). At the same time, we described in detail all the structural elements of the model as well as its input parameters, in order to minimize any issue of transparency and facilitate the reproducibility and circulation of the results among researchers.ResultsUsing the no AIT strategy as a comparator, and the Incremental Cost Effectiveness Ratio (ICER) as a statistic to summarize the cost-effectiveness of a health care intervention, we could conclude that:SCIT systematically outperforms SLIT, except when a full societal perspective is considered. For example, for T = 9 and a pollen season of 60 days, we have ICER = €16,729 for SCIT vs. ICER = €15,116 for SLIT (in the full societal perspective).For longer pollen seasons or longer follow-up duration the ICER decreases, because each patient experiences a greater clinical benefit over a larger time span, and Quality-adjusted Life Year (QALYs) gained per cycle increase accordingly.Assuming that no clinical benefit is achieved after premature discontinuation, and that at least three years of immunotherapy are required to improve clinical manifestations and perceiving a better quality of life, ICERs become far greater than €30,000.If the immunotherapy is effective only at the peak of the pollen season, the relative ICERs rise sharply. For example, in the scenario where no clinical benefit is present after premature discontinuation of immunotherapy, we have ICER = €74,770 for SCIT vs. ICER = €152,110 for SLIT.The distance between SCIT and SLIT strongly depends on under which model the interventions are meta-analyzed.ConclusionsEven though there is a considerable evidence that SCIT outperforms SLIT, we could not state that both SCIT and SLIT (or only one of these two) can be considered cost-effective for ARC, as a reliable threshold value for cost-effectiveness set by national regulatory agencies for pharmaceutical products is missing. Moreover, the impact of model input parameters uncertainty on the reliability of our conclusions needs to be investigated further. ]]> <![CDATA[TGFβ1 mimetic peptide modulates immune response to grass pollen allergens in mice]]> https://www.researchpad.co/article/elastic_article_6979 TGFβ1‐mim downregulated major cytokines involved in Th1 and Th2 responses in mice sensitized to Phl p 5. Treatment of mice with the mimetic during sensitization to Phl p 5 induced Treg production, suppressed specific IgE and IgG1, IgE‐mediated basophil degranulation, induced IgA antibodies and IL‐10 secretion. In an IL‐4 reporter model, TGFβ1‐mim suppressed Th2 polarization induced by grass pollen extract.

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<![CDATA[A new oncolytic <i>Vaccinia virus</i> augments antitumor immune responses to prevent tumor recurrence and metastasis after surgery]]> https://www.researchpad.co/article/N88927970-d085-458f-92ed-e97c95defddd Local recurrence and remote metastasis are major challenges to overcome in order to improve the survival of patients with cancer after surgery. Oncolytic viruses are a particularly attractive option for prevention of postsurgical disease as they offer a non-toxic treatment option that can directly target residual tumor deposits and beneficially modulate the systemic immune environment that is suppressed post surgery and allows residual disease escape from control. Here, we report that a novel Vaccinia virus (VV), VVΔTKΔN1L (with deletion of both thymidine kinase (TK) and N1L genes) armed with interleukin 12 (IL-12), can prolong postoperative survival when used as a neoadjuvant treatment in different murine and hamster surgical models of cancer.MethodsA tumor-targeted replicating VV with deletion of TK gene and N1L gene (VVΔTKΔN1L) was created. This virus was armed rationally with IL-12. The effect of VVΔTKΔN1L and VVΔTKΔN1L-IL12 on modulation of the tumor microenvironment and induction of tumor-specific immunity as well the feasibility and safety as a neoadjuvant agent for preventing recurrence and metastasis after surgery were assessed in several clinically relevant models.ResultsVVΔTKΔN1L can significantly prolong postoperative survival when used as a neoadjuvant treatment in three different surgery-induced metastatic models of cancer. Efficacy was critically dependent on elevation of circulating natural killer cells that was achieved by virus-induced cytokine production from cells infected with N1L-deleted, but not N1L-intact VV. This effect was further enhanced by arming VVΔTKΔN1L with IL-12, a potent antitumor cytokine. Five daily treatments with VVΔTKΔN1L-IL12 before surgery dramatically improved postsurgical survival. VVΔTKΔN1L armed with human IL-12 completely prevented tumor recurrence in surgical models of head and neck cancer in Syrian hamsters.ConclusionsThese data provide a proof of concept for translation of the regime into clinical trials. VVΔTKΔN1L-IL12 is a promising agent for use as an adjuvant to surgical treatment of solid tumors. ]]> <![CDATA[Preclinical PET imaging of bispecific antibody ERY974 targeting CD3 and glypican 3 reveals that tumor uptake correlates to T cell infiltrate]]> https://www.researchpad.co/article/N80690d3b-6438-42fa-a762-c899ebfbb4d0 Bispecific antibodies redirecting T cells to the tumor obtain increasing interest as potential cancer immunotherapy. ERY974, a full-length bispecific antibody targeting CD3ε on T cells and glypican 3 (GPC3) on tumors, has been in clinical development However, information on the influence of T cells on biodistribution of bispecific antibodies, like ERY974, is scarce. Here, we report the biodistribution and tumor targeting of zirconium-89 (89Zr) labeled ERY974 in mouse models using immuno-positron emission tomography (PET) imaging.MethodsTo study both the role of GPC3 and CD3 on the biodistribution of [89Zr]Zr-N-suc-Df-ERY974, 89Zr-labeled control antibodies targeting CD3 and non-mammalian protein keyhole limpet hemocyanin (KLH) or KLH only were used. GPC3 dependent tumor targeting of [89Zr]Zr-N-suc-Df-ERY974 was tested in xenograft models with different levels of GPC3 expression. In addition, CD3 influence on biodistribution of [89Zr]Zr-N-suc-Df-ERY974 was evaluated by comparing biodistribution between tumor-bearing immunodeficient mice and mice reconstituted with human immune cells using microPET imaging and ex vivo biodistribution. Ex vivo autoradiography was used to study deep tissue distribution.ResultsIn tumor-bearing immunodeficient mice, [89Zr]Zr-N-suc-Df-ERY974 tumor uptake was GPC3 dependent and specific over [89Zr]Zr-N-suc-Df-KLH/CD3 and [89Zr]Zr-N-suc-Df-KLH/KLH. In mice engrafted with human immune cells, [89Zr]Zr-N-suc-Df-ERY974 specific tumor uptake was higher than in immunodeficient mice. Ex vivo autoradiography demonstrated a preferential distribution of [89Zr]Zr-N-suc-Df-ERY974 to T cell rich tumor tissue. Next to tumor, highest specific [89Zr]Zr-N-suc-Df-ERY974 uptake was observed in spleen and lymph nodes.Conclusion[89Zr]Zr-N-suc-Df-ERY974 can potentially be used to study ERY974 biodistribution in patients to support drug development. ]]> <![CDATA[Characterization of tumor mutation burden, PD-L1 and DNA repair genes to assess relationship to immune checkpoint inhibitors response in metastatic renal cell carcinoma]]> https://www.researchpad.co/article/Nb196bd4e-e98c-4fc9-9715-0b77bd7eabe8 Immune checkpoint inhibitors (ICIs) have expanded treatment options for metastatic renal cell carcinoma (mRCC); however, there are limited predictive biomarkers for response to ICIs in this indication, with programmed death-ligand 1 (PD-L1) status demonstrating little predictive utility in mRCC. While predictive of ICI response in other tumor types, the utility of tumor mutation burden (TMB) in mRCC is unclear. Here, we assess TMB, loss of antigen presentation genes and PD-L1 status correlated with outcomes to ICI treatment in mRCC.MethodsTumor samples from 34 patients with mRCC treated with ICI therapy at Duke Cancer Institute were retrospectively evaluated using Personal Genome Diagnostics elio tissue complete (RUO version), a tumor genomic profiling assay for somatic variants, TMB, microsatellite status and genomic status of antigen presentation genes. Tumor samples were also analyzed with the Dako 28-8 PD-L1 immunohistochemistry assay. Deidentified clinical information was extracted from the medical record, and tumor response was evaluated based on the Response Evaluation Criteria In Solid Tumors (RECIST) V.1.1 criteria.ResultsPatients were stratified by overall response following ICI therapy and designated as progressive disease (PD; n=18) or disease control groups (DC; n=16). TMB scores ranged from 0.36 to 12.24 mutations/Mb (mean 2.83 mutations/Mb) with no significant difference between the PD and DC groups (3.01 vs 2.63 mutations/Mb, respectively; p=0.7682). Interestingly, 33% of PD patients displayed loss of heterozygosity of major histocompatibility complex class I genes (LOH-MHC) vs 6% of DC patients. Nine of 34 samples were PD-L1-positive (4 in the PD group; 5 in the DC group), suggesting no correlation between PD-L1 expression and response to ICI therapy. Notably, the DC group displayed an enrichment of mutations in DNA repair genes (p=0.04), with 68.8% exhibiting at least one mutated homologous recombination repair (HRR)-related gene compared with only 38.9% of the PD group (p=0.03).ConclusionsOverall, neither TMB nor PD-L1 correlated with ICI response and TMB was not significantly associated with PD-L1 expression. The higher incidence of LOH-MHC in PD group suggests that loss of antigen presentation may restrict response to ICIs. Separately, enrichment of HRR gene mutations in the DC group suggests potential utility in predicting ICI response and a potential therapeutic target, warranting future studies. ]]> <![CDATA[Combined immunotherapy with nivolumab and ipilimumab with and without local therapy in patients with melanoma brain metastasis: a DeCOG* study in 380 patients]]> https://www.researchpad.co/article/N2af82b8b-7d16-4be9-8535-2f0cfad0f527 Nivolumab combined with ipilimumab have shown activity in melanoma brain metastasis (MBM). However, in most of the clinical trials investigating immunotherapy in this subgroup, patients with symptomatic MBM and/or prior local brain radiotherapy were excluded. We studied the efficacy of nivolumab plus ipilimumab alone or in combination with local therapies regardless of treatment line in patients with asymptomatic and symptomatic MBM.MethodsPatients with MBM treated with nivolumab plus ipilimumab in 23 German Skin Cancer Centers between April 2015 and October 2018 were investigated. Overall survival (OS) was evaluated by Kaplan-Meier estimator and univariate and multivariate Cox proportional hazard analyses were performed to determine prognostic factors associated with OS.ResultsThree hundred and eighty patients were included in this study and 31% had symptomatic MBM (60/193 with data available) at the time of start nivolumab plus ipilimumab. The median follow-up was 18 months and the 2 years and 3 years OS rates were 41% and 30%, respectively. We identified the following independently significant prognostic factors for OS: elevated serum lactate dehydrogenase and protein S100B levels, number of MBM and Eastern Cooperative Oncology Group performance status. In these patients treated with checkpoint inhibition first-line or later, in the subgroup of patients with BRAFV600-mutated melanoma we found no differences in terms of OS when receiving first-line either BRAF and MEK inhibitors or nivolumab plus ipilimumab (p=0.085). In BRAF wild-type patients treated with nivolumab plus ipilimumab in first-line or later there was also no difference in OS (p=0.996). Local therapy with stereotactic radiosurgery or surgery led to an improvement in OS compared with not receiving local therapy (p=0.009), regardless of the timepoint of the local therapy. Receiving combined immunotherapy for MBM in first-line or at a later time point made no difference in terms of OS in this study population (p=0.119).ConclusionImmunotherapy with nivolumab plus ipilimumab, particularly in combination with stereotactic radiosurgery or surgery improves OS in asymptomatic and symptomatic MBM. ]]> <![CDATA[A first-in-human phase 1 dose escalation study of spartalizumab (PDR001), an anti–PD-1 antibody, in patients with advanced solid tumors]]> https://www.researchpad.co/article/N6b833652-3362-45cd-87d6-12273a83218b

Background

Spartalizumab is a humanized IgG4κ monoclonal antibody that binds programmed death-1 (PD-1) and blocks its interaction with PD-L1 and PD-L2. This phase 1/2 study was designed to assess the safety, pharmacokinetics, and preliminary efficacy of spartalizumab in patients with advanced or metastatic solid tumors.

Methods

In the phase 1 part of the study, 58 patients received spartalizumab, intravenously, at doses of 1, 3, or 10 mg/kg, administered every 2 weeks (Q2W), or 3 or 5 mg/kg every 4 weeks (Q4W).

Results

Patients had a wide range of tumor types, most commonly sarcoma (28%) and metastatic renal cell carcinoma (10%); other tumor types were reported in ≤3 patients each. Most patients (93%) had received prior antineoplastic therapy (median three prior lines) and two-thirds of the population had tumor biopsies negative for PD-L1 expression at baseline. The maximum tolerated dose was not reached. The recommended phase 2 doses were selected as 400 mg Q4W or 300 mg Q3W. No dose-limiting toxicities were observed, and adverse events included those typical of other PD-1 antibodies. The most common treatment-related adverse events of any grade were fatigue (22%), diarrhea (17%), pruritus (14%), hypothyroidism (10%), and nausea (10%). Partial responses occurred in two patients (response rate 3.4%); one with atypical carcinoid tumor of the lung and one with anal cancer. Paired tumor biopsies from patients taken at baseline and on treatment suggested an on-treatment increase in CD8+ lymphocyte infiltration in patients with clinical benefit.

Conclusions

Spartalizumab was well tolerated at all doses tested in patients with previously treated advanced solid tumors. On-treatment immune activation was seen in tumor biopsies; however, limited clinical activity was reported in this heavily pretreated, heterogeneous population. The phase 2 part of this study is ongoing in select tumor types.

Trial registration number

NCT02404441.

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<![CDATA[Compound kushen injection relieves tumor-associated macrophage-mediated immunosuppression through TNFR1 and sensitizes hepatocellular carcinoma to sorafenib]]> https://www.researchpad.co/article/Nc7f0f26d-1d05-45e0-9406-fc0cc9610ebd

Background

There is an urgent need for effective treatments for hepatocellular carcinoma (HCC). Immunotherapy is promising especially when combined with traditional therapies. This study aimed to investigate the immunomodulatory function of an approved Chinese medicine formula, compound kushen injection (CKI), and its anti-HCC efficiency in combination with low-dose sorafenib.

Methods

Growth of two murine HCC cells was evaluated in an orthotopic model, a subcutaneous model, two postsurgical recurrence model, and a tumor rechallenge model with CKI and low-dose sorafenib combination treatment. In vivo macrophage or CD8+ T cell depletion and in vitro primary cell coculture models were used to determine the regulation of CKI on macrophages and CD8+ T cells.

Results

CKI significantly enhanced the anticancer activity of sorafenib at a subclinical dose with no obvious side effects. CKI and sorafenib combination treatment prevented the postsurgical recurrence and rechallenged tumor growth. Further, we showed that CKI activated proinflammatory responses and relieved immunosuppression of tumor-associated macrophages in the HCC microenvironment by triggering tumor necrosis factor receptor superfamily member 1 (TNFR1)-mediated NF-κB and p38 MAPK signaling cascades. CKI-primed macrophages significantly promoted the proliferation and the cytotoxic ability of CD8+ T cells and decreased the exhaustion, which subsequently resulted in apoptosis of HCC cells.

Conclusions

CKI acts on macrophages and CD8+ T cells to reshape the immune microenvironment of HCC, which improves the therapeutic outcomes of low-dose sorafenib and avoids adverse chemotherapy effects. Our study shows that traditional Chinese medicines with immunomodulatory properties can potentiate chemotherapeutic drugs and provide a promising approach for HCC treatment.

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<![CDATA[Oncolytic vesicular stomatitis virus–based cellular vaccine improves triple-negative breast cancer outcome by enhancing natural killer and CD8+ T-cell functionality]]> https://www.researchpad.co/article/N21329a41-9fab-4d8c-b32d-ab19b4a100f2 ]]> <![CDATA[Head-to-head comparison of in-house produced CD19 CAR-T cell in ALL and NHL patients]]> https://www.researchpad.co/article/N216a910f-9d48-460c-a6ed-35c87525cffd

Background

CD19 chimeric antigen receptor T (CAR-T) cells demonstrate remarkable remission rates in pediatric and adult patients with refractory or relapsed (r/r) acute lymphoblastic leukemia (ALL) and non-Hodgkin's lymphoma (NHL). In 2016, we initiated a clinical trial with in-house produced CD19 CAR-T cells with a CD28 co-stimulatory domain. We analyzed, for the first time, differences in production features and phenotype between ALL and NHL patients.

Methods

Non-cryopreserved CAR-T cells were produced from patients’ peripheral blood mononuclear cells within 9 to 10 days. 93 patients with r/r ALL and NHL were enrolled under the same study. CAR-T cells of ALL and NHL patients were produced simultaneously, allowing the head-to-head comparison.

Results

All patients were heavily pretreated. Three patients dropped out from the study due to clinical deterioration (n=2) or production failure (n=1). Cells of ALL patients (n=37) expanded significantly better and contained more CAR-T cells than of NHL patients (n=53). Young age had a positive impact on the proliferation capacity. The infusion products from ALL patients contained significantly more naïve CAR-T cells and a significantly higher expression of the chemokine receptor CXCR3. PD-1, LAG-3, TIM-3, and CD28 were equally expressed. 100% of ALL patients and 94% of NHL patients received the target dose of 1×10e6 CAR-T/kg. The overall response rate was 84% (30/36) in ALL and 62% (32/52) in NHL. We further compared CAR-T cell infusion products to tumor infiltrating lymphocytes (TIL), another common type of T cell therapy, mainly clinically effective in solid tumors. CAR-T cells contained significantly more naïve T cells and central memory T cells and significantly less CCR5 compared to TIL infusion products.

Conclusions

The in-house production of CAR-T cells is highly efficient and fast. Clinical response rate is high. CAR-T cells can be successfully produced for 99% of patients in just 9 to 10 days. Cells derived from ALL patients demonstrate a higher proliferation rate and contain higher frequencies of CAR-T cells and naïve T cells than of NHL patients. In addition, understanding the differences between CAR-T and TIL infusion products, may provide an angle to develop CAR-T cells for the treatment of solid tumors in the future.

Trial registration number

ClinicalTrials.gov; CAR-T: NCT02772198, First posted: May 13, 2016; TIL: NCT00287131, First posted: February 6, 2006.

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<![CDATA[Quality of life in long-term survivors of advanced melanoma treated with checkpoint inhibitors]]> https://www.researchpad.co/article/N1857e08f-dee2-4579-bba7-ddb0d698f0b5

Background

Immune checkpoint inhibitors (CIs) have revolutionized treatment of advanced melanoma, leading to an emerging population of long-term survivors. Survivors’ quality of life (QOL) and symptom burden are poorly understood. We set out to evaluate symptom burden and QOL in patients with advanced melanoma alive more than 1 year after initiating CI therapy.

Methods

Cross-sectional surveys, accompanied by chart review of patients with advanced melanoma treated with CIs at Memorial Sloan Kettering Cancer Center, completed therapy, and were alive >1 year after treatment initiation. Surveys were administered between February and August 2018. Surveys included: European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30, EuroQOL, items from Patient-Reported Outcomes version of the Common Terminology Criteria for Adverse Events and Fatigue Severity Scale.

Results

We included 90 patients. The most common CI regimens were ipilimumab plus nivolumab (53%) and pembrolizumab (41%); most patients (71%) were not treated in clinical trials. Median time from CI therapy initiation was 40 months and from last dose was 28 months. Fatigue was reported by 28%, with higher fatigue scores in women than men; 12% reported difficulty sleeping. Aching joints (17%) and muscles (12%) were fairly common. Level of functioning was generally high. Overall QOL was excellent though 40% reported ‘some or moderate’ problems with anxiety/depression and 31% with pain/discomfort.

Conclusions

After CI therapy, long-surviving advanced melanoma patients commonly report fatigue but otherwise have moderate symptom burden and good QOL. Ensuring appropriate symptom management will optimize clinical outcomes for these patients.

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<![CDATA[Pre-existing inflammatory immune microenvironment predicts the clinical response of vulvar high-grade squamous intraepithelial lesions to therapeutic HPV16 vaccination]]> https://www.researchpad.co/article/Nff1ff5ca-eb0c-4739-8a5a-93458833b194

Background

Vulvar high-grade squamous intraepithelial lesion (vHSIL) is predominantly induced by high-risk human papilloma virus type 16 (HPV16). In two independent trials, therapeutic vaccination against the HPV16 E6 and E7 oncoproteins resulted in objective partial and complete responses (PRs/CRs) in half of the patients with HPV16+ vHSIL at 12-month follow-up. Here, the prevaccination and postvaccination vHSIL immune microenvironment in relation to the vaccine-induced clinical response was investigated.

Methods

Two novel seven-color multiplex immunofluorescence panels to identify T cells (CD3, CD8, Foxp3, Tim3, Tbet, PD-1, DAPI) and myeloid cells (CD14, CD33, CD68, CD163, CD11c, PD-L1, DAPI) were designed and fully optimized for formalin-fixed paraffin-embedded tissue. 29 prevaccination and 24 postvaccination biopsies of patients with vHSIL, and 27 healthy vulva excisions, were stained, scanned with the Vectra multispectral imaging system, and automatically phenotyped and counted using inForm advanced image analysis software.

Results

Healthy vulvar tissue is strongly infiltrated by CD4 and CD8 T cells expressing Tbet and/or PD-1 and CD14+HLA-DR+ inflammatory myeloid cells. The presence of such a coordinated pre-existing proinflammatory microenvironment in HPV16+ vHSIL is associated with CR after vaccination. In partial responders, a disconnection between T cell and CD14+ myeloid cell infiltration was observed, whereas clinical non-responders displayed overall lower immune cell infiltration. Vaccination improved the coordination of local immunity, reflected by increased numbers of CD4+Tbet+ T cells and HLA-DR+CD14+ expressing myeloid cells in patients with a PR or CR, but not in patients with no response. CD8+ T cell infiltration was not increased after vaccination.

Conclusion

A prevaccination inflamed type 1 immune contexture is required for stronger vaccine-induced immune infiltration and is associated with better clinical response. Therapeutic vaccination did not overtly increase immune infiltration of cold lesions.

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<![CDATA[Peritumoral administration of IFNβ upregulated mesenchymal stem cells inhibits tumor growth in an orthotopic, immunocompetent rat glioma model]]> https://www.researchpad.co/article/N224ebe1d-8900-46c4-a602-49a996ba58f7

Background

Immunotherapy with IFNβ is a promising strategy for treating malignant glioma. However, systemic administration of IFNβ is inadequate because of low intratumoral concentration and major adverse effects. This study aimed to determine whether mesenchymal stem cells (MSCs) can be used as cellular vehicles to locally deliver IFNβ for glioma therapy by using in vivo MRI tracking.

Methods

A recombinant lentiviral vector encoding IFNβ and ferritin heavy chain (FTH) reporter genes was constructed to transduce MSCs. The effectiveness and safety of transduction were assessed. After the IFNβ and FTH overexpressed MSCs (IFNβ-FTH-MSCs) were transplanted into intracranial orthotopic rat F98 gliomas via peritumoral, intracerebral, intratumoral or intra-arterial injection, MRI was performed to track IFNβ-FTH-MSCs and to evaluate their therapeutic effect on glioma in vivo, as validated by histologic analysis, quantitative PCR and ELISA assays.

Results

MSCs were efficiently and safely transduced to upregulate their IFNβ secretion and FTH expression by the constructed lentivirus. After peritumoral injection, IFNβ-FTH-MSCs appeared as hypointense signals on MRI, which gradually diminished but remained visible until 11 days. Compared with other administration routes, only peritumoral injection of IFNβ-FTH-MSCs showed a remarkable inhibition on the glioma growth. Nearly 30% of IFNβ-FTH-MSCs survived up to 11 days after peritumoral injection, while most of IFNβ-FTH-MSCs injected via other routes died within 11 days. IFNβ-FTH-MSCs grafted peritumorally secreted IFNβ persistently, leading to pronounced Batf3+ dendritic cells and CD8+ T lymphocyte infiltration within the glioma.

Conclusions

MSCs can be used as cellular vehicles of IFNβ to treat malignant glioma effectively via peritumoral injection.

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<![CDATA[Potent STING activation stimulates immunogenic cell death to enhance antitumor immunity in neuroblastoma]]> https://www.researchpad.co/article/N07ecef8e-37d2-4354-a5d1-d0b2e3fbdee3

Background

Neuroblastoma (NB) is a childhood cancer for which new treatment options are needed. The success of immune checkpoint blockade in the treatment of adult solid tumors has prompted the exploration of immunotherapy in NB; however, clinical evidence indicates that the vast majority of NB patients do not respond to single-agent checkpoint inhibitors. This motivates a need for therapeutic strategies to increase NB tumor immunogenicity. The goal of this study was to evaluate a new immunotherapeutic strategy for NB based on potent activation of the stimulator of interferon genes (STING) pathway.

Methods

To promote STING activation in NB cells and tumors, we utilized STING-activating nanoparticles (STING-NPs) that are designed to mediate efficient cytosolic delivery of the endogenous STING ligand, 2’3’-cGAMP. We investigated tumor-intrinsic responses to STING activation in both MYCN-amplified and non-amplified NB cell lines, evaluating effects on STING signaling, apoptosis, and the induction of immunogenic cell death. The effects of intratumoral administration of STING-NPs on CD8+ T cell infiltration, tumor growth, and response to response to PD-L1 checkpoint blockade were evaluated in syngeneic models of MYCN-amplified and non-amplified NB.

Results

The efficient cytosolic delivery of 2’3’-cGAMP enabled by STING-NPs triggered tumor-intrinsic STING signaling effects in both MYCN-amplified and non-amplified NB cell lines, resulting in increased expression of interferon-stimulated genes and pro-inflammatory cytokines as well as NB cell death at concentrations 2000-fold to 10000-fold lower than free 2’3’-cGAMP. STING-mediated cell death in NB was associated with release or expression of several danger associated molecular patterns that are hallmarks of immunogenic cell death, which was further validated via cell-based vaccination and tumor challenge studies. Intratumoral administration of STING-NPs enhanced STING activation relative to free 2’3’-cGAMP in NB tumor models, converting poorly immunogenic tumors into tumoricidal and T cell-inflamed microenvironments and resulting in inhibition of tumor growth, increased survival, and induction of immunological memory that protected against tumor re-challenge. In a model of MYCN-amplified NB, STING-NPs generated an abscopal response that inhibited distal tumor growth and improved response to PD-L1 immune checkpoint blockade.

Conclusions

We have demonstrated that activation of the STING pathway, here enabled by a nanomedicine approach, stimulates immunogenic cell death and remodels the tumor immune microenvironment to inhibit NB tumor growth and improve responses to immune checkpoint blockade, providing a multifaceted immunotherapeutic approach with potential to enhance immunotherapy outcomes in NB.

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<![CDATA[A hypoallergenic peptide mix containing T cell epitopes of the clinically relevant house dust mite allergens]]> https://www.researchpad.co/article/Nb73e6a4a-8898-4566-86c6-a1e00bb9d005

Abstract

Background

In the house dust mite (HDM) Dermatophagoides pteronyssinus, Der p 1, 2, 5, 7, 21, and 23 have been identified as the most important allergens. The aim of this study was to define hypoallergenic peptides derived from the sequences of the six allergens and to use the peptides and the complete allergens to study antibody, T cell, and cytokine responses in sensitized and nonsensitized subjects.

Methods

IgE reactivity of HDM‐allergic and non‐HDM‐sensitized individuals to 15 HDM allergens was established using ImmunoCAP ISAC technology. Thirty‐three peptides covering the sequences of the six HDM allergens were synthesized. Allergens and peptides were tested for IgE and IgG reactivity by ELISA and ImmunoCAP, respectively. Allergenic activity was determined by basophil activation. CD4+ T cell and cytokine responses were determined in PBMC cultures by CFSE dilution and Luminex technology, respectively.

Results

House dust mite allergics showed IgE reactivity only to complete allergens, whereas 31 of the 33 peptides lacked relevant IgE reactivity and allergenic activity. IgG antibodies of HDM‐allergic and nonsensitized subjects were directed against peptide epitopes and higher allergen‐specific IgG levels were found in HDM allergics. PBMC from HDM‐allergics produced higher levels of IL‐5 whereas non‐HDM‐sensitized individuals mounted higher levels of IFN‐gamma, IL‐17, pro‐inflammatory cytokines, and IL‐10.

Conclusion

IgG antibodies in HDM‐allergic patients recognize peptide epitopes which are different from the epitopes recognized by IgE. This may explain why naturally occurring allergen‐specific IgG antibodies do not protect against IgE‐mediated allergic inflammation. A mix of hypoallergenic peptides containing T cell epitopes of the most important HDM allergens was identified.

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<![CDATA[Comparison of iRECIST versus RECIST V.1.1 in patients treated with an anti-PD-1 or PD-L1 antibody: pooled FDA analysis]]> https://www.researchpad.co/article/Nfeb15609-ff31-4e1d-997f-52e9512e785d

Background

Response criteria developed when cytotoxic chemotherapy was the predominant therapeutic modality to treat patients with cancer, do not capture the full spectrum of tumor response patterns observed with anti-PD-1/PD-L1 antibody treatment. iRECIST was developed to capture both typical and atypical response patterns.

Methods

Target, non-target, and new lesion measurements for 7920 patients receiving anti-PD-1/PD-L1 antibody (n=4751) or anti-CTLA-4 antibody (n=613) or undergoing chemotherapy (n=2556) from 14 randomized controlled trials submitted to the U.S. Food and Drug Administration were used to calculate the best overall response, objective response rate and progression-free survival (PFS) per iRECIST (iPFS) and Response Evaluation Criteria in Solid Tumours (RECIST). Associations between either PFS or iPFS and overall survival (OS) were evaluated using the method adopted by Oba et al.1

Results

Among 4751 anti-PD-1/PD-L1-antibody treated patients, 31.5% (95% CI 30.2% to 32.9%) and 30.5% (95% CI 29.2% to 31.8%) achieved an objective response per iRECIST or RECIST V.1.1, respectively. OS among the 48 patients with objective response by iRECIST only resembled that in patients with responses per RECIST V.1.1. The association between iPFS and OS was R2=0.277 and that between PFS and OS was R2=0.260.

Conclusions

Patients treated with anti-PD-1/PD-L1 antibodies with initial progressive disease per RECIST V.1.1 can experience prolonged stability or substantial reductions in tumor burden per iRECIST, atypical response patterns associated with prolonged OS. In the subgroup of patients with atypical responses, the application of iRECIST retrospectively in the evaluation of the objective response durations and the magnitude of PFS results in large differences compared with RECIST V.1.1. For the overall pooled population, the magnitude of these differences was modest, although a large proportion of patients had no further tumor assessments following RECIST V.1.1-defined progressive disease. Prospective studies employing iRECIST will be required to assess whether this response criteria more fully captures the benefit of immune checkpoint inhibitors.

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<![CDATA[Non-thermal histotripsy tumor ablation promotes abscopal immune responses that enhance cancer immunotherapy]]> https://www.researchpad.co/article/N85eda1a4-36b2-43d2-8dec-50da2514844c

Background

Developing the ability to use tumor-directed therapies to trigger potentially therapeutic immune responses against cancer antigens remains a high priority for cancer immunotherapy. We hypothesized that histotripsy, a novel non-invasive, non-thermal ablation modality that uses ultrasound-generated acoustic cavitation to disrupt tissues, could engender adaptive immune responses to tumor antigens.

Methods

Immunocompetent C57BL/6 mice inoculated with flank melanoma or hepatocellular carcinoma tumors were treated with histotripsy, thermal ablation, radiation therapy, or cytotoxic T lymphocyte-associated protein-4 (CTLA-4) blockade checkpoint inhibition. Lymphocyte responses were measured using flow cytometric and immunohistochemical analyses. The impact of histotripsy on abscopal immune responses was assessed in mice bearing bilateral tumors, or unilateral tumors with pulmonary tumors established via tail vein injection.

Results

Histotripsy ablation of subcutaneous murine melanoma tumors stimulated potent local intratumoral infiltration of innate and adaptive immune cell populations. The magnitude of this immunostimulation was stronger than that seen with tumor irradiation or thermal ablation. Histotripsy also promoted abscopal immune responses at untreated tumor sites and inhibited growth of pulmonary metastases. Histotripsy was capable of releasing tumor antigens with retained immunogenicity, and this immunostimulatory effect was associated with calreticulin translocation to the cellular membrane and local and systemic release of high mobility group box protein 1. Histotripsy ablation potentiated the efficacy of checkpoint inhibition immunotherapy in murine models of melanoma and hepatocellular carcinoma.

Conclusions

These preclinical observations suggest that non-invasive histotripsy ablation can be used to stimulate tumor-specific immune responses capable of magnifying the impact of checkpoint inhibition immunotherapy.

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<![CDATA[Late cardiac adverse events in patients with cancer treated with immune checkpoint inhibitors]]> https://www.researchpad.co/article/N234d2ac7-b992-4454-a4f3-fa23389efb7d

Background

Immune checkpoint inhibitor (ICI)-associated early cardiac adverse events (CAEs), mostly acute and fulminant myocarditis, have been well characterized and mainly occur during the first 90 days after ICI therapy initiation. ICI-associated late CAEs (occurring after the first 90 days of treatment) have not yet been described.

Methods

First, we compared characteristics of a cohort involving early (defined as a CAE time to onset (TTO) of <90 days after ICI therapy initiation) and late (defined as a CAE TTO of ≥90 days after ICI therapy initiation) ICI-associated CAE consecutive cases who were referred to three French cardio-oncology units. Second, ICI-associated CAE cases were searched in VigiBase, the WHO global individual case safety report database, and early and late ICI-associated CAEs were compared.

Results

In the cohort study, compared with early CAE cases (n=19, median TTO of 14 days), late ICI-associated CAE cases (n=19, median TTO of 304 days) exhibited significantly more left ventricular systolic dysfunction (LVSD) and heart failure (HF) and less frequent supraventricular arrhythmias. In VigiBase, compared with early cases (n=437, 73.3%, median TTO 21 days), the late ICI-associated CAE reports (n=159, 26.7%, median TTO 178 days) had significantly more frequent HF (21.1% vs 31.4%, respectively, p=0.01). Early and late ICI-associated CAE cases had similarly high mortality rates (40.0% vs 44.4% in the cohort and 30.0% vs 27.0% in VigiBase, respectively).

Conclusions

Late CAEs could occur with ICI therapy and were mainly revealed to be HF with LVSD.

Trial registration numbers

NCT03678337, NCT03882580, and NCT03492528.

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<![CDATA[Correlation of plasma exosomal microRNAs with the efficacy of immunotherapy in EGFR / ALK wild-type advanced non-small cell lung cancer]]> https://www.researchpad.co/article/N3320bee0-c8a0-4921-967c-f208ff33f359

Background

Immunotherapy has become an important treatment option for patients with advanced non-small cell lung cancer (NSCLC). At present, none of these existing biomarkers can effectively stratify true responders and there is an urgent need for identifying novel biomarkers. Exosomes derived from the serum of patients with cancer have been proven to be reliable markers for cancer diagnosis. Here, we explored the possibility of using plasma-derived exosomal microRNAs as potential biomarkers for optimal selection of patients with advanced EGFR/ALK negative NSCLC to immunotherapy.

Methods

From June 2017 to February 2019, 30 patients with advanced EGFR/ALK wild-type (WT) NSCLC who received PD-1/PD-L1 inhibitors were enrolled. The efficacy evaluation was conducted after every three cycles of treatment according to RECIST 1.1. Plasma samples of these patients were collected before the administration of PD-1/PD-L1 inhibitors as baseline, and after every three cycles if the patients achieved partial response (PR) or complete response. Plasma from seven healthy individuals was also collected as normal control. Exosomes were prepared by ultracentrifugation followed by total RNA extraction, and exosome-derived miRNAs were profiled using small RNA next-generation sequencing followed by differential expression analysis.

Results

In order to identify biomarker for better response, all five patients who achieved PR and four patients with progressive disease (PD) at efficacy evaluation were included for differential expression analysis. Based on unsupervised hierarchical clustering, exosomal miRNA expression profile was significantly altered in patients with NSCLC compared with normal controls with a total of 155 differentially expressed exosomal miRNAs. Interestingly, hsa-miR-320d, hsa-miR-320c, and hsa-miR-320b were identified significantly upregulated in the PD groups compared with the PR group at baseline before the treatment. In addition, we identified that hsa-miR-125b-5p, a T-cell suppressor, showed a trend of increased expression in the PD group at baseline and was significantly downregulated in the post-treatment plasma exosomes compared with pre-treatment samples of the PR patients.

Conclusion

Patients with NSCLC represent unique plasma exosomal miRNA profiles. Hsa-miR-320d, hsa-miR-320c, and hsa-miR-320b were identified as potential biomarkers for predicting the efficacy of immunotherapy in advanced NSCLCs. When T-cell suppressor hsa-miR-125b-5p was downregulated during the treatment, the patients may obtain increased T-cell function and respond well to immunotherapy.

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<![CDATA[Phase II study of pembrolizumab and capecitabine for triple negative and hormone receptor-positive, HER2−negative endocrine-refractory metastatic breast cancer]]> https://www.researchpad.co/article/N1c192872-2faa-4143-bd8e-433d69be508f

Background

Response rates to single agent immune checkpoint blockade in unselected pretreated HER2−negative metastatic breast cancer (MBC) are low. However, they may be augmented when combined with chemotherapy.

Methods

We conducted a single-arm, phase II study of patients with triple negative (TN) or hormone receptor-positive endocrine-refractory (HR+) MBC who were candidates for capecitabine. Patients were treated with pembrolizumab 200 mg intravenously day 1 and capecitabine 1000 mg/m2 by mouth twice daily on days 1–14 of a 21-day cycle. The primary end point was median progression-free survival (mPFS) compared with historic controls and secondary end points were overall response rate (ORR), safety and tolerability. The study had 80% power to detect a 2-month improvement in mPFS with the addition of pembrolizumab over historic controls treated with capecitabine alone.

Results

Thirty patients, 16 TN and 14 HR+ MBC, were enrolled from 2017 to 2018. Patients had a median age of 51 years and received a median of 1 (range 0–6) prior lines of therapy for MBC. Of 29 evaluable patients, the mPFS was 4.0 (95% CI 2.0 to 6.4) months and was not significantly longer than historic controls of 3 months. The median overall survival was 15.4 (95% CI 8.2 to 20.3) months. The ORR was 14% (n=4), stable disease (SD) was 41% (n=12) and clinical benefit rate (CBR=partial response+SD>6 months) was 28% (n=8). The ORR and CBR were not significantly different between disease subtypes (ORR 13% and 14%, CBR 25% and 29% for TN and HR+, respectively). The 1-year PFS rate was 20.7% and three patients have ongoing responses. The most common adverse events were low grade and consistent with those seen in MBC patients receiving capecitabine, including hand-foot syndrome, gastrointestinal symptoms, fatigue and cytopenias. Toxicities at least possibly from pembrolizumab included grade 3 or 4 liver test abnormalities (7%), rash (7%) and diarrhea (3%), as well as grade 5 hepatic failure in a patient with liver metastases.

Conclusions

Compared with historical controls, pembrolizumab with capecitabine did not improve PFS in this biomarker unselected, pretreated cohort. However, some patients had prolonged disease control.

Trial registration number

NCT03044730.

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