bluuebunny/crossref_metadata_2025 huggingface dataset:
A phase I safety study of oncolytic vaccinia virus delivered by adipose stromal vascular fraction cells.
Authors: Minev Boris
Published: July 2019

39

Background: A major obstacle to the oncolytic virus treatment approach has been the rapid virus elimination by patient’s immune system. We hypothesized that oncolytic viruses would be protected and delivered efficiently to tumor sites by autologous adipose stromal vascular fraction (SVF) cells. Here, we report the results of a study to determine the safety and feasibility of this approach in cancer patients. Methods: In this single-arm, open-label safety study, 24 patients with advanced solid tumors and 2 patients with AML were treated with a single administration of the oncolytic virus ACAM2000 (vaccinia) delivered by SVF cells. Patients received ACAM2000/SVF by intravenous application, or by a combination of intravenous and intratumoral or intra-peritoneal injections. The primary endpoint was safety/tolerability. Secondary endpoints assessed overall survival and induction of immune responses. Blood samples were collected at multiple time points for quantifying vaccinia virus DNA in peripheral blood and to determine the plasma cytokine levels and the effects on several immune cell types. Results: No serious toxicities were reported. Eight subjects reported an AE: self-limiting skin lesions, lasting 7 to 18 days. No infusion-related AEs were reported. No AEs leading to study discontinuation were reported. Viral DNA was detected in all patients immediately following treatment. Interestingly, in 8 patients viral DNA disappeared 1 day and re-appeared 1 week post treatment, suggesting active viral replication, possibly at tumor sites. This viral DNA reappearance correlated with longer survival of these patients. No major increase in cytokine levels was observed in any of the patients. No correlation between cytokine levels and skin lesions was noted. Flow cytometry showed gradual changes suggesting improved immune cell activation status. Tumor size reduction was documented in several patients. Conclusions: Treatment with ACAM2000/SVF in patients with advanced solid tumors and AML is safe and well tolerated, with clear antitumor effects in several patients. These promising initial clinical results merit further investigation of therapeutic utility. Clinical trial information: ISRCTN#10201650.
A phase II trial with the combination of plinabulin (plin) pegfilgrastim (peg): Evaluation of the reversal of peg’s immune-suppressive potential by the addition of plin to peg.
Authors: Blayney Douglas W. , Ogenstad Stephan , Shi Yuankai , Feng Ji Feng , Zhang Qingyuan , Sun Tao , Du Lihua , Huang Lan , Mohanlal Ramon
Published: July 2019

4

Background: Peg is a long-acting G-CSF used for prevention of Chemotherapy Induced Neutropenia (CIN). Peg stimulates granulopoiesis in bone marrow and causes a temporary overshoot in absolute neutrophil count (ANC). High NLR is a negative prognostic marker in esophageal, renal cancer and melanoma (Zhou, Nature 2016; Ma, Nature 2018). Decreased Lymphocyte-to Monocyte Ratio (LMR) is another negative prognostic marker (Sierzega; Ann Surg Onc 2017). Peg single agent (SA), but not Plin SA, increased NLR, and decreased LMR (Blayney ESMO 2018) after Docetaxel (Doc). We analyzed whether Plin added to Peg would reverse Peg’s immune-suppressive potential by analyzing NLR and LMR with Peg SA and with Plin+Peg. Methods: NLR and LMR were calculated in cycle 1 of Ph2 study BPI-2358-106 with either Peg SA (6 mg; n = 22), Plin SA (20 mg/m2; n = 15) or Peg 6 mg and Plin 20 mg/m2 (Peg+Plin; n = 21). NLR and LMR were calculated after day (D) 8, since Peg increases leukocytes after D8, and were performed through D15. Plin was given D1 of chemotherapy (Doc, Doxorubicin, Cyclophosphamide) in Breast Cancer patients (pts); Peg was given D2. Results: The percentage (%) of pts with grade 4 neutropenia was lowered from 59% with Peg SA to 38% by adding Plin to Peg. The % of pts with an ANC exceeding upper limit of normal (8x10E9/L) was lowered from 50% with Peg SA to 31%, by adding Plin to Peg. The table summarizes the % of patients with NLR ≥ 5 and LMR ≤3.2 over time with Peg SA, Plin SA and Peg+Plin. Peg-induced immune-suppressive NLR and or LMR levels occurred in 50% or more of pts, and in a significantly lower % of pts by adding Plin to Peg (p < 0.0076 for NLR and p < 0.073 for LMR on D13). Conclusions: Peg, but not Plin generates a potentially deleterious NLR and LMR which was significantly reversed by the addition of Plin to Peg. The Peg+Plin combination improves efficacy for CIN and reversed Peg’s potentially immune-suppressive NLR and MLR phenotype. Clinical trial information: NCT03294577. [Table: see text]
Histology could predict a “hot” or a “cold” gastric tumor?
Authors: Zurlo Ina Valeria , Strippoli Antonia , Calegari Maria Alessandra , Martini Maurizio , Cocomazzi Alessandra , Orlandi Armando , Cassano Alessandra , Vita Emanuele , Garufi Giovanna , Di Stefano Brunella , Bagala Cinzia , Bria Emilio , Pozzo Carmelo , Basso Michele
Published: July 2019

44

Background: The emerging role of immunotherapy (IT) in cancer treatments has increased the research about tumor microenvironment (TME), tumor infiltrating lymphocytes (TILs) function and their TME regulation. Nowadays ongoing trial are showing conflicting preliminary data about the efficacy of IT in advanced gastric cancer (GC). Therefore, we performed this exploratory analysis to evaluate the correlation between histology, TILs density (reported as CD4/CD8 tissue ratio), neutrophil-lymphocytes ratio (NLR) and response outcome in GC patients who underwent cytotoxic neoadjuvant treatment (NAD). Methods: CD4+ and CD8+ expression was assessed by immunohistochemistry (IHC) in pre-NAD biopsies. NLR was calculated on baseline complete blood count. A cut-off value to define low or high NLR has been selected on 3.0, based on literature data. X2 test was used to explore the correlation between histology, CD4/CD8 ratio, NLR and response. Results: We analyzed 10 diffuse and 10 intestinal GC histotypes. In the intestinal-type CD4/CD8 ratio was lower (ratio range 1:15 - 1:20) with a predominant count of CD8+ suggesting a hot and inflamed TME compared to the diffuse cohort (ratio range 1:3 -1:5) where both CD8+ and CD4+ density was lower (p=0.03). Baseline NLR was calculated in 18 out of 20 pts. All intestinal GCs showed a low NLR (<3) while all diffuse GCs displayed a high cutoff (p=0.03). CD4/CD8 ratio resulted associated to histology (p=0.025) and response outcome (p=0.0003). NLR was statistically related to histology (p=0.03) and CD4/CD8 tissue ratio (p=0.03), confirming a different systemic inflammatory status and TME according to histology. Conclusions: Despite the small sample size, our exploratory analysis shows a possible correlation between histology, systemic inflammation and TME behavior (“hot” vs“cold”) described by NLR and TILs concentration (CD4/CD8 ratio) respectively and response to NAD. Intestinal-type seems to be a “hot” tumor whereas diffuse-type appears “cold”. Future clinical trial should analyze the impact of histology and TME features on IT efficacy and the appropriate strategy to convert “cold” tumor increasing TILs density.
Results of a phase II study evaluating trifluridine/tipiracil plus nivolumab in patients with heavily pretreated microsatellite-stable (MSS) metastatic colorectal cancer (mCRC).
Authors: Patel Manish R. , Falchook Gerald Steven , Hamada Kensuke , Makris Lukas , Winkler Robert E. , Gordon Gilad Shalag , Bendell Johanna C.
Published: July 2019

48

Background: Patients (pts) with colorectal cancer (CRC) with microsatellite instability (MSI) have recently been shown to respond to anti–programmed death (PD)-1 drugs. Preclinical data suggest that trifluridine/tipiracil (FTD/TPI) treatment converts MSS CRC cells to MSI, sensitizing them to the activity of anti–PD-1 drugs. The aim of this phase 2 study was to evaluate this hypothesis. Methods: This was a multicenter, single-arm, safety lead-in, phase 2 study that used Simon’s 2-stage design to evaluate the safety and efficacy of FTD/TPI (35 mg/m2 twice daily on days 1-5 and 8-12 every 28 days) plus nivolumab (3 mg/kg every 2 weeks) in pts with heavily pretreated MSS mCRC. Pts had histologically proven metastatic or locally advanced colorectal adenocarcinoma that was MSS (assessed by a local laboratory based on either previous or fresh biopsy), ≥1 measurable lesion for RECIST and immune-related response criteria (irRC) assessment, and failure of ≥2 previous lines of chemotherapy. Six pts were to be enrolled in the safety lead-in, and in order to proceed to Simon’s stage 2, ≥2 of the first 15 pts had to demonstrate a partial or complete response within 6 months based on irRC assessment. Results: The first 6 dose-limiting toxicity (DLT)-evaluable pts enrolled tolerated dosing with no DLTs. A total of 18 pretreated pts enrolled in the first stage (50% males; median age 56.5 yr), among whom 72% had colon cancer and 100% had MSS disease, 56% with RAS mutations. Pts received a median of 2.5 cycles of study therapy (range 1-8). The most common grade 3/4 adverse events (AEs) were neutropenia (28%); diarrhea (17%); and nausea, abdominal pain, fatigue, and anemia (11% each). No pts discontinued treatment due to AEs. No pts achieved a tumor response (either per RECIST or irRC), and the study did not progress to the second stage. Median (6-month) progression-free survival was 2.8 months (21%) per RECIST and 2.2 months (30%) per irRC. Conclusions: The combination of FTD/TPI and nivolumab was feasible and tolerated at the full dose of both compounds. Adding nivolumab to FTD/TPI did not provide additional clinical benefit in pts with previously treated MSS mCRC. Clinical trial information: NCT02860546.
Production of autologous monocytes stimulated ex vivo with peg-interferon alfa 2b and interferon gamma 1b for intraperitoneal administration in phase I clinical trial.
Authors: Duemler Anna , Green Daniel S , Highfill Steven L. , Stroncek David , Zoon Kathryn , Annunziata Christina M.
Published: July 2019

5

Background: Monocytes are myeloid cells that reside in the blood and bone marrow and respond to inflammation. At the site of inflammation, monocytes express cytokines and chemokines. Monocytes are cytotoxic to tumor cells in the presence of pro-inflammatory cytokines such as Interferon Alpha and Interferon Gamma. We previously showed that monocytes stimulated with both interferons (IFNs) result in synergistic killing of ovarian cancer cells. We aimed to develop this cell therapy product for clinical application. Methods: Counter flow elutriation was performed on healthy donors. The monocyte-containing, RO-fraction was assessed for total monocyte number, purity, viability, and cytotoxicity with and without cryopreservation. All 5 fractions from the elutriation procedure were also assessed by flow cytometry to measure the percent of immune cell subsets. This procedure is now implemented in a clinical trial where 8 patients completed the apheresis and elutriation process for a total of 13 runs. Results: Iterative monocyte isolation using counter flow elutriation with or without cryopreservation can yield over 2 billion monocytes for each subject with high purity. We show that monocytes are stable, viable, and retain cytotoxic functions when cultured with IFNs. Flow cytometric analysis shows expected heterogeneity in the collected monocytes. In each case, the elutriation run met pre-set release criteria for both total monocyte number and purity requirements for the therapeutic product. Conclusions: We demonstrated that large scale isolation of monocytes can be achieved with elutriation from either healthy donors or patients with advanced, chemotherapy resistant ovarian cancer. Monocytes can be cryopreserved and maintain viability and cytotoxic function in the final cell therapy product prior to infusion. We translated these observations to a currently accruing clinical trial using adoptive cell transfer of autologous monocytes stimulated ex-vivo with IFNs and infused into the peritoneal cavity of patients with advanced, chemotherapy resistant, ovarian cancer. (Protocol NCT00327067). Clinical trial information: NCT02948426.
Low molecular weight heparin (LMWH) enhances immunotherapy (I) activity in pancreatic cancer cells.
Authors: Karamouzis Michalis , Bokas Alexandros , Kyriakopoulou Georgia , Koustas Evangelos , Sarantis Panagiotis , Papakotoulas Pavlos , Schizas Dimitrios , Papalampros Alexandros , Felekouras Evangelos , Liakakos Theodoros , Papavassiliou Athanasios G.
Published: July 2019

50

Background: The aim is to investigate the effect of LMWH in combination with chemotherapy (C) and I in PC. Methods: BxPC-3, PANC-1, MIA PACA-2 cell lines were exposed in Tinzaparin (T) (0.5, 0.7, 0.9 μΜ) and/or 1 μΜ Nab-Paclitaxel (A) and/or 1 μΜ Gemcitabine (G) and/or 1 μΜ Nivolumab (NI), 1 μΜ, Pembrolizumab (PE) and 1 μΜ ipilimumab (IPI). Protein levels of VEGFR2, p-ERK1/2, p-AKT detected by Western blotting. Cells viability was measured through MTT assay. Results: Increasing protein levels of VEGFR2 was observed in all PC cell lines exposed to a constant dose of T and/or A,G. NI and PE +/- with IPI increased VEGFR2. In NI/PE+IPI+T scheme VEGFR2 levels were decreased (0.1-0.7 folds) in a dose dependent way in mtKRAS cells (PANC1, MIAPACA2). C (G or A) + I decreased VEGFR2 protein levels in mtKRAS cells PANC1 (0.1-0.4 folds), MIAPACA2 (0.1-0.6 folds) in double scheme. T+G/A+NI/PE+IPI scheme increased VEGFR2 in all PC cells. PANC-1 cells were decreased 40% in 0,7T+IPI+(NI or PE) after 48hours. The effect of these schemes on signaling pathways (MEK/EKR, AKT/mTOR) and apoptosis was identified through pERK1/2, pAKT, PARP, cl. caspase-3. Conclusions: These results identify the different effect of I alone or in combination with T and C in PC cells bearing mutant or wild type KRAS. Double or triple combination reduced VEGFR2 protein levels in mtKRAS and not in wtKRAS PC cells. The 0,7T+IPI+(NI or PE) combination decreases cell viability of PC cells through apoptosis. Testing of the combinatorial scheme T+chemo+IPI+(NI or PE) with PANC-1 PC in scid mice is ongoing and will be presented. NC:not changed, -:<20% protein vs control, +:>20% protein vs control, ++:>40% protein vs control. [Table: see text]
Association of intratumoral FoxP3 T-regulatory lymphocytes and perineural invasion in colorectal adenocarcinoma.
Authors: Messersmith Lynn , Williams Grant , Lombardo Jamie , Hickerson Annelies , Campf Jessica , Brady Robert , Collins Ryan , Peoples George Earl , Clifton Guy T.
Published: July 2019

51

Background: In colorectal cancer, higher densities of lymphocytes in the tumor microenvironment (TME) have been associated with better clinical outcomes. FoxP3+ regulatory T-cells (Tregs) are a subset of lymphocytes that play an immunosuppressive role in the TME. However, the impact of Tregs in the TME in colon cancer prognosis is more controversial. We evaluated the densities of FoxP3+ Tregs at multiple locations in matched endoscopic biopsies and resection specimens from patients with colonic adenocarcinoma to assess concordance of Treg densities between locations, and the association with prognostic factors. Methods: Patients with banked, matched endoscopic biopsies and surgically resected colon adenocarcinoma specimens from a single institution from 2006-2016 were selected for evaluation. Paraffin embedded tissue samples were cut and stained with FoxP3 immunohistochemical stain. The densities of FoxP3 positive cells were counted within a 1 mm2 area at the center of the tumor and at the invasive margin. The densities of FoxP3 positive lymphocytes were compared between the center and invasive margin, and to prognostic factors. Results: 107 matched endoscopic biopsies and surgical resection specimens were evaluated. A moderate-strong correlation was noted in levels of FoxP3+ cells between endoscopic biopsies and resected specimens at the center of the tumor (r= 0.68) and invasive margin (r=0.69). Higher FoxP3 densities were associated with a decreased rate of perineural invasion (P= 0.040). Levels of Tregs in endoscopic biopsies were correlated with the levels in the larger tumor of resected colon adenocarcinoma specimens. There was a weak correlation between increased density of Tregs and lower anatomic stage (R2 = 0.05). Conclusions: Tregs are a potential biomarker that can be evaluated in neoadjuvant immunomodulatory therapies in clinical trials to assess for response. Moreover, Treg levels are associated with perineural invasion, a predictive factor for decreased response to chemotherapy, underscoring the potential for immunomodulatory therapies in colorectal adenocarcinoma.
iRGD in combination with IL-2 reprograms tumor immunosuppression.
Authors: Botta Gregory P. , De Mendoza Tatiana Hurtado , Jarvelainen Harri , Ruoslahti Erkki
Published: July 2019

55

Background: Fibrotic solid tumors have lagged in immunotherapy efficacy. Although breast cancer (BC) shows modest single-agent activity, pancreatic ductal adenocarcinoma (PDAC) immunotherapy has repeatedly failed in clinical trials. A protective desmoplastic, inflammatory reaction encapsulates BC and PDAC where it can make up to 80% of the tumor microenvironment (TME). Reports in BC and PDAC patients and mouse models suggest that tumoricidal effector CD8+ T-cells are indeed present, yet suppressed by regulatory CD4+/CD25+/FoxP3+ T-cells (Tregs) and myeloid cells. Long-term PDAC and BC survivors harbor CD8+ T-cells by immunohistochemistry (IHC), and although inactivated (CD107a-), they are not terminally exhausted (PD-1low). Further, when CD8+ T-cells were found in large quantities within a treatment-naïve biopsy, that patient had an increased overall survival. We hypothesize that low doses of the T-cell proliferative cytokine IL-2 can class switch the TME T-cells if specifically concentrated within the tumor by the stroma-penetrating peptide iRGD. Methods: Subcutaneous BC tumors (4T1) and PDAC (KPC ) tumors were formed in immunocompetent mouse models. Mice were treated with either vehicle, iRGD, IL-2, or both in combination. Tumors were preserved for IHC or enzymatically digested for FACS. CD45+ live cells were fluorescently labeled for effector T-cells (CD4+/CD44+ or CD8+/CD44+), Tregs (CD4+/CD25+/FoxP3+), or cytotoxic T-cells (CD8+/CD44+/Granzyme B+/IL-2+). Results: Versus normal controls, tumors from BC and PDAC both showed a subsequent increase in bulk CD3+ T-cells within the tumor microenvironment (14.3% ± 5 vs. 27.6% ± 8). A significant increase in CD3+ T-cells within all tumors (10%) occured with iRGD only, IL-2 only, or iRGD + IL-2 treatment. Whereas sub-populations of T-cells in the iRGD only and IL-2 only treatment groups was overwhelming composed of Tregs (5%) at CD4/Treg and CD8/Treg ratios of 1.75 and 0.5 respectively, the combination of iRGD + IL-2 shifted the T-cell sub-populations away from Tregs (1.5%) and towards increased CD4/Treg and CD8/Treg ratios (4 and 12 respectively). Conclusions: The combination of iRGD + IL-2 is capable of reprogramming the immunosuppressive Treg tumor microenvironment, increasing effector CD4+ and CD8+ T-cells.
Differences in immune tumor microenvironment between primary and metastatic castration-resistant prostate cancer.
Authors: Yang Yuanquan , Zhang Yali , Wang Jianmin , Krolewski John , Levine Ellis Glenn , Mohler James , Chatta Gurkamal S. , Kalinski Pawel
Published: July 2019

58

Background: Androgen deprivation therapy (ADT)-induced immunosuppression has been described in animal models as contributing to castration-resistant prostate cancer (CRPC) development, but the clinical relevance of these observations has not been established. In this study, we compared the immune tumor microenvironment (iTME) of primary prostate cancer (PPC) versus metastatic CRPC (mCRPC). Methods: Genomic and clinically annotated data were obtained of PPC and mCRPC from the TCGA provisional and SU2C/PCF databases. Patients without RNA-seq data were excluded. 22 iTME cell subsets were estimated using CIBERSORT LM22 algorithm. Relative cell proportions and gene expression in log-transformed FPKM were compared using Wilcoxon tests. Results: 499 PPC and 118 mCRPC were studied. Compared to PPC, mCRPC had higher percentage of M2 macrophages (24.6% vs. 10.2%, p<0.0001). High M2 in mCRPC was associated with 2.5-, 6- and 19.5-fold increases in IL-10, VEGFA and ARG1 mRNA levels, respectively (p<0.0001). T- cell exhaustion markers, LAG3 and CD160, were upregulated in mCRPC by 43.2% and 266.7% (p<0.0001). Although CD8 T-cells were higher in mCRPC, the CD8/M2 ratio was lower (1.1 vs. 1.5, p=0.002). Prior use of abiraterone or enzalutamide in the mCRPC cohort (n=54) did not alter iTME cell fractions compared to AR antagonist naïve mCRPC. The detailed iTME comparisons were listed in Table. Conclusions: Our data indicate the development of tumor-favoring iTME in the course of progression to mCRPC while on ADT. The iTME is characterized by increased M2 macrophage infiltration that may provide a novel and important therapeutic target. [Table: see text]
Role for immune checkpoint blockade in BRCA2-mutant prostate cancer.
Authors: Panda Anshuman , Stein Mark N. , Riedlinger Gregory , Bhanot Gyan , Ganesan Shridar
Published: July 2019

59

Background: Except for rare cases with microsatellite instability, prostate cancer has low mutation burden and low response rate to immune checkpoint blockade (ICB). Genomic correlates of response to ICB in microsatellite stable (MSS) prostate cancer are currently unknown. Here we describe an exceptional response to ICB in BRCA2-mutant prostate cancer and explore immunologic features of BRCA-mutant tumors. Methods: A patient with BRCA2-mutant MSS prostate cancer who progressed on PARP inhibitor therapy was treated with pembrolizumab. Another 8 cases of BRCA2-mutant prostate cancer were evaluated for lymphocyte infiltration and PD-L1 expression by a pathologist. The Cancer Genome Atlas (TCGA) dataset was used to evaluate BRCA-mutant tumors from multiple histology. Presence of putative pathogenic mutations in BRCA1/2 were tested for association with mRNA levels of CD8+ T cell marker ( CD8A), immune checkpoint genes (in PD-1, CTLA-4 pathways), and expression of endogenous retroviruses (ERV). Markers of homologous recombination (HR) defects, namely number of Signature 3 mutations and large ( > 3bp) indels, were also analyzed. Results: Initial patient with BRCA2-mutant MSS prostate cancer had a rapid and ongoing response to pembrolizumab. Analysis of local cohort will be presented. In the TCGA prostate cancer dataset, BRCA2-mutant tumors showed significant overexpression of CD8A, PD-1 and CTLA-4 pathway genes, and ERV3-2. Similar results were observed in BRCA1-mutant (but not BRCA2-mutant) ER+ HER2− breast cancer, but not in BRCA-mutant triple-negative breast and ovarian cancer. Analyses of HR defect markers corroborated these observations. Conclusions: BRCA-mutation accompanied by ERV3-2 overexpression, observed in BRCA2-mutant prostate and BRCA1-mutant ER+ HER2− breast cancer, is associated with CD8+ T cell infiltration and checkpoint pathway upregulation. The effect of BRCA1/2 mutation on immunogenicity may be very tissue and/or cell-of-origin specific, with different cancer types having different levels of immune activation. The association between ERV expression and BRCA2-mutation in prostate cancer requires further investigation. BRCA2-mutant prostate cancers are a class of MSS tumors that may be sensitive to ICB.
Cell proliferation as a biomarker for response to immune checkpoint inhibitors in highly inflamed renal cell carcinoma.
Authors: Pabla Sarabjot , Zhu Jason , Labriola Matthew , Gupta Rajan , George Daniel J. , McCall Shannon , Yau Edwin , Conroy Jeffrey M. , Glenn Sean T. , Nesline Mary , Papanicolau-Sengos Antonios , Burgher Blake , Lenzo Felicia L. , Zhang Tian , Morrison Carl
Published: July 2019

61

Background: Cell proliferation is an important marker of survival in many tumors and we hypothesized that this attribute could be related to response to immune checkpoint inhibitors in RCC. Previously we reported (SITC 2018) moderately proliferative lung cancer has a much higher response rate than either poorly or highly proliferative tumors. Methods: 69 FFPE tumor samples of RCC were evaluated by RNA-seq to measure transcript levels of 394 immune related genes, including 10 related to cell proliferation (BUB1, CCNB2, CDK1, CDKN3, FOXM1, KIAA0101, MAD2L1, MELK, MKI67, TOP2A). Cell proliferation, defined as the mean mRNA expression of these 10 genes was evaluated for association with ORR to ICIs by RECIST v1.1 criteria for both PD-L1 IHC positive and negative cases. Cell proliferation for each case was split into 3 tertiles of poorly ( < 33), moderately (33-66) and highly ( > 66) proliferative compared to a reference population. Poorly and highly proliferative were grouped for comparison to moderately proliferative tumors. Tumors were inflamed or non-inflamed based upon RNA‐seq analysis of CD8 compared to a reference population of more than 500 cases of multiple tumors. Non-inflamed, or immune desert tumors, defined as the lower 25th percentile of rank for CD8+ T-cells, and greater than 75th percentile of rank as inflamed. Results: In our cohort of 69 patient the overall ORR was 18.8%. 15.9% of tumors were non-inflamed with an ORR of 9.1%. For 36.2% inflamed tumor the ORR was 32%. For cell proliferation 62.2% were poorly proliferative, 8.7% were highly proliferative, and 29% were moderately. ORR in moderately proliferative tumors was 30% versus 14.2% in poorly/highly proliferative tumors. In inflamed tumors, ORR in moderately proliferative tumors was 37.5% as opposed to 17.6% in poorly/highly proliferative tumors. In 11 non-inflamed tumors, there was only one responder, which was a poorly/highly proliferative tumor. Conclusions: Cell proliferation may play a crucial role in distinguishing RCC patients who may have a clinical benefit to ICI, including the important subgroup of inflamed tumors. Moderately proliferative tumors have a higher ORR than their poorly/highly counterparts.
Evaluation of tumor microenvironment and biomarkers of immune checkpoint inhibitor (ICI) response in metastatic renal cell carcinoma (mRCC).
Authors: Zhu Jason , Pabla Sarabjot , Labriola Matthew , Gupta Rajan T. , McCall Shannon , George Daniel J. , Dressman Devin , Glenn Sean T. , Nesline Mary , George Saby , Morrison Carl , Zhang Tian
Published: July 2019

63

Background: ICIs are now standard of care for mRCC; however, there are few biomarkers to predict ICI response. Recent data from atezolizumab/bevacizumab trials in mRCC suggest tumors with high Teffhigh/PD-L1+ are more likely to respond to ICI. Here, we use this Teff gene panel as well as other markers of inflammation in the tumor microenvironment to correlate with ICI responses. Methods: This multicenter study evaluated 69 pts with mRCC treated with ICIs. FFPE tumor samples were evaluated by RNA sequencing to measure transcript levels of genes related Teff status. Teff status was defined as the mRNA expression of 17 genes (CD8, CD27, IFNG, GZMA, GZMB, PRF1, EOMES, CXCL9, CXCL10, CXCL11, CD274, CTLA4, FOXP3, TIGIT, IDO1, PSMB9, TAP1), with Teffhigh/low separated at the median. PD-L1 positivity was defined as ≥1% TPS based on Dako 22C3 IHC assay, and TMB high as > 10 mutations per megabase. Inflamed tumors were defined as CD8 expression in the top 75th percentile compared to a large reference population of multiple tumor types. Best responses to ICI was determined by an expert radiologist using RECIST 1.1 criteria. Inflamed tumor status, Teff gene expression, PD-L1 positive, and TMB were associated with disease control (DC, defined as CR, PR, or stable disease). DC comparisons were tested using a chi-squared test with Yates’s continuity correction. Results: DC was 63% (5/8) amongst PD-L1 positive pts and 52% (31/60) in PD-L1 negative patients (p = 0.84). Only 2 pts were TMB high. The majority of mRCC tumors (97%, 67/69) were TMB low. 6-month DC in TMB high tumors was 50% (1/2) and 49.3% (33/67) in TMB low tumors (p = 1.0). 36 pts were classified as Teffhigh and 33 patients were classified as Tefflow. 6-month DC was 61% (22/36) in the Teffhigh cohort and 36% (12/33) in the Tefflow cohort (p = 0.069). 6-month DC was 64% of inflamed tumors (16/25) vs 41% of non-inflamed tumors (18/44) (p = 0.111). Conclusions: TMB high and PD-L1 expression do not reliably predict for DC in pts with mRCC. Utilizing a gene signature score may better predict ICI response.
Effect of age and gender on expression levels of markers of immune cell infiltration and immune checkpoint pathways in patients with muscle-invasive transitional cell carcinoma of the bladder: A retrospective study of 50 patients treated with radical cystectomy.
Authors: Alanee Shaheen Riadh , Holland Bradley , Delfino Kristin , Dynda Danuta
Published: July 2019

65

Background: Older age and female gender have been associated with worse outcomes in patients with muscle invasive bladder cancer undergoing radical cystectomy. Reduced immune response has been implicated in disease metastasis and worse survival. The objective of our study was to determine the expression patterns of various cellular proteins active in immune pathways in bladder cancer patients, and assess the correlation between age, gender, and expression of these immune markers. Methods: Tissue samples were obtained from equally distributed male/female patients with/without lymph node metastasis on final pathology after undergoing radical cystectomy for transitional cell carcinoma (TCC) of the bladder from 2009-2011 (n = 50). Immunohistochemistry (IHC) for CD3, CD4, CD8, LAG3, CD56, TIM3, PD-1 and PD-L1 were performed and scored by a single pathologist (scoring was on 0 to 100% scale). Statistical analyses investigated association between age, gender, lymph node metastasis, and IHC results. Results: Mean age at surgery was 67 yrs (range 50 to 78 yrs); all patients were Caucasians. Statistical analyses showed no association between patients' age, gender, and the expression of any of the immune markers (p > 0.05). Similarly, the staining scores for the immune markers were not noted to be correlated with LN metastasis. Correlation between stains showed a negative correlation between CD56 and PD-L1 (-0.286, p = 0.047) and between PD-1 and PD-L1 (-0.381, p = 0.007). Conclusions: Although age and female gender have been associated with worse outcomes in bladder cancer, this association may be independent of the immune pathways active in the disease. Increased expression of PD-L1 is associated significantly with suppression of anti-tumor natural killer cells in the transitional cell carcinoma of the bladder.
Efficacy of first-line immune checkpoint inhibitors in patients with sarcomatoid and/or rhabdoid (S/R) metastatic renal cell carcinoma (mRCC).
Authors: Bakouny Ziad , Abou Alaiwi Sarah , Nassar Amin , Steinharter John A. , Wei Xiao X. , McGregor Bradley Alexander , Harshman Lauren Christine , Choueiri Toni K.
Published: July 2019

66

Background: Patients with mRCC with S/R components tend to have a poor prognosis with few therapeutic options available. Recent data suggest that immune checkpoint inhibitor (ICI)-based therapies may be especially effective for these patients. Our aim was to evaluate the efficacy of ICI-based therapies in patients with S/R mRCC. Methods: We retrospectively assessed objective response rate (ORR), progression free survival (PFS) & overall survival (OS) of patients with S/R mRCC treated at our institution with first-line ICI-based therapies and compared these to those of patients treated with first-line non-ICI-based therapies. Univariable and multivariable (adjusted for IMDC group) Cox and logistic regressions were performed. Results: 92 patients (70 S, 9 R, and 13 S&R) patients were included, of which 74 with a clear-cell component. For all patients (regardless of therapy), 74 (80.4%) patients experienced a PFS event (progression or death) and 52 (56.5%) died at 25.3 months (m) median follow-up. Overall median PFS was 5.3 m (95% CI= 3.4–7.2) and 24 m OS rate was 39.5% (27.4–51.7). Out of 78 patients in whom response was evaluable, ORR was 30.8% (20.4–41.2). Patients treated with ICI-based therapies had significantly better ORR, PFS, and OS on multivariable analysis (table). Conclusions: mRCC patients with S/R components have significantly better ORR, PFS, and OS with first-line ICI-based compared to non-ICI-based therapies. These data support the use of ICI-based therapies for patients with S/R mRCC. [Table: see text]
Factors associated with severity of immune checkpoint inhibitor gastroenterocolitis requiring hospitalization in melanoma patients.
Authors: Hughes Michael Sang , Zheng Hui , Zubiri Leyre , Dougan Michael , Allen Ian Matthew , Molina Gabriel , Lumish Melissa , Mooradian Megan , Reynolds Kerry Lynn
Published: July 2019

81

Background: Immune checkpoint inhibitors (ICIs) have resulted in a subset of patients experiencing durable responses in solid and liquid malignancies. ICIs can be associated with adverse events, including gastroenterocolitis (GEC), that require immunosuppression and even hospitalization. Currently, no data determine the severity of patients hospitalized for ICI-related GEC. Our primary objective was to identify candidate surrogate endpoints that may predict the severity of ICI-related GEC; our secondary objective was to identify predictors of glucocorticoid (GC) response. Methods: In a retrospective cohort study, we identified melanoma patients who developed ICI-related GEC requiring hospitalization at Massachusetts General Hospital between 6/1/11 and 12/31/17. We extracted clinical, laboratory, radiographic, and pathological data; linear regression was used to estimate trends. Additional subgroup analyses were performed. Results: 69/1842 (3.7%) melanoma patients treated with ICI developed GEC requiring hospitalization (total 98 admissions). Mean age was 64 +/- 13; 42 (61%) were male. Readmission rate was 21/69 (30.4%); 6/21 (28.6%) required multiple readmissions. 90/98 (92%) were confirmed by histopathologic examination. 26/69 (37.7%) responded to GCs; 43/69 (62.3%) required second-line immunosuppression (e.g. TNFi) and/or operative intervention. ECOG PS (at initial ICI administration) was associated with response of GEC to GCs (p = 0.04). Lymphocyte count (p = 0.03), % lymphocyte count (p = 0.02), and LDH (p = 0.004) on admission were independently associated with GEC requiring second-line immunosuppression. Conclusions: Admissions for ICI-related GEC are infrequent, but they are associated with a high readmission rate and the need for second-line immunosuppression. We show that high ECOG PS at time of ICI administration may be a predictor of GC response in ICI-related GEC requiring hospitalization. We also propose that low % lymphocyte count and high LDH may serve as clinical biomarkers of severity in ICI-related GEC requiring hospitalization. Our findings suggest the need for further research and validation of these proposed biomarkers.
Multisystem immune-related adverse events from anti-PD-1/PD-L1 in patients with lung cancer: Incidence, clinical patterns, management, and outcomes.
Authors: Shankar Bairavi , Zhang Jiajia , Barasa Durrant , Forde Patrick M. , Feliciano Josephine Louella , Marrone Kristen , Kelly Ronan Joseph , Ettinger David S. , Hann Christine L. , Brahmer Julie R. , Naidoo Jarushka
Published: July 2019

84

Background: Anti-PD-1/PD-L1 immune checkpoint inhibitors (ICIs) for cancer may cause immune-related adverse events (irAEs). Large clinical trials and meta-analyses have identified the spectrum of single organ-specific irAEs that may occur with these agents. However, patients treated with these agents may develop irAEs involving multiple organ systems. The prevalence and clinical patterns of multi-system irAEs and their management have yet to be elucidated. Methods: Patients with lung cancer treated with either PD-1/PD-L1 monotherapy or PD-1/PD-L1-based combinations at Johns Hopkins Hospital were identified. Clinical, radiologic and pathologic data were stored in an IRB-approved database. irAEs were identified through retrospective chart review and confirmed by a multidisciplinary team. Multi-system irAEs were defined as irAEs in +1 organ system. Patients with multi-system irAEs, their clinical patterns, management and outcomes were identified. Results: 319 patients were identified (NSCLC: 299, 93.7%; SCLC: 20, 6.3%) and received treatment with either PD-1/PD-L1 monotherapy (197, 61.8%) or combinations (122, 38.2%: + chemotherapy = 42; +immunotherapy = 41; +other = 39). Of these patients, 77 (24.1%) developed 1 irAE, and 16 (5%) developed multi-system irAEs (2 irAEs: 14; 3 irAEs: 2). The most common irAEs were pneumonitis (42, 13.2%), dermatitis (11, 3.4%), and hypothyroidism (9, 2.8%). The most common multi-system irAEs was pneumonitis/dermatitis (3, 3.9%). Patients who developed dermatitis, colitis, or hypothyroidism were most likely to develop multi-system irAEs (all p < 0.05). Management and outcome data for individual and multi-system irAEs will be presented. Conclusions: Patients treated with ICIs may develop multi-system irAEs. In the first report of this clinical entity, we identified that 5% of lung cancer patients treated with PD-1/PD-L1 developed multi-system irAEs, and that those who developed dermatitis, colitis, or hypothyroidism were most likely to develop multi-system events. These data have important implications for interdisciplinary patient management in the era of cancer immunotherapy.
Preliminary study into the impact of immunotherapy on patterns of care and healthcare service utilization in stage IV non-small cell lung cancer in a tertiary hospital setting.
Authors: Guo Xiao Yue , Gunawan Ben , Sanmugarajah Jasotha
Published: July 2019

92

Background: The advent of immunotherapy for Non-Small Cell Lung Cancer (NSCLC) has dramatically altered cancer care. There is increasing clinical evidence to support immunotherapy improving disease-free progression and survivorship. However, there is limited data on how this impacts healthcare in terms of service utilization. Methods: We conducted a retrospective study on patients newly diagnosed with Stage IV NSCLC at a tertiary referral hospital with a large catchment area in Australia. Data was collected for the years 2013 (pre-immunotherapy) and 2016 (immunotherapy in use) to investigate the impact of immunotherapy on treatment patterns, survivorship and healthcare service utilisation. A total of 62 patients were included in the study with equal numbers in both cohorts. Results: Preliminary analysis indicates that since the introduction of immunotherapy in NSCLC treatment protocols, there has been a trend towards improved survivorship. There was a 19% increase in the number of patients surviving to 12 months in the 2016 cohort compared with 2013 cohort patients. Median survival was 6 months and 8 months for 2013 and 2016 cohorts respectively. There was a significantly greater burden of visits to outpatient clinics and treatment day units in the 2016 cohort. We also found fewer Emergency Department presentations and hospital admissions in the 2016 cohort compared with their 2013 counterparts. Conclusions: In conclusion, our study demonstrates increasing healthcare utilisation in ambulatory cancer services with decreased Emergency presentations and hospital admissions following the introduction of immunotherapy for patients with advanced NSCLC. Although this preliminary study suggested important trends, our sample size was small and these effects need to be confirmed in a larger cohort. [Table: see text]
Neoadjuvant atezolizumab in resectable NSCLC patients: Updated clinical and immunophenotyping results from a multicenter trial.
Authors: Oezkan Filiz , He Kai , Owen Dwight Hall , Pietrzak Maciej , Rusch Valerie W. , Chaft Jamie E. , Kitzler Rhonda , Nicholas Alan , Schulze Katja , Johnson Ann , Phan See , Bunn Paul A. , Kris Mark G. , Kwiatkowski David J. , Johnson Bruce E. , Wistuba Ignacio Ivan , Lee Jay M. , Hirsch Fred R. , Lozanski Gerard , Carbone David Paul
Published: July 2019

99

Background: Targeting PD-L1/PD-1 to activate anti-tumor immunity is associated with improved response and survival compared to chemo in NSCLC pts. We present a preliminary analysis of the clinical efficacy, safety and peripheral blood (PB) immunophenotyping from an ongoing multicenter atezolizumab (atezo) neoadjuvant immunotherapy study in resectable NSCLC. Methods: Pts received 2 cycles of atezo, 1200mg, days 1, 22 before resection. Tumor biopsies and PB were obtained pre-atezo & pre-surgery. The biomarker evaluable population (BEP) included pts with paired PB analyzed within 72 hrs by 10-color flow cytometry (IMMUNOME) and major pathological response (MPR) assessment (defined as ≤ 10% residual tumor). The primary endpoint was MPR. Secondary endpoints included safety, MPR by PD-L1, OS, and DFS. Immunophenotypic analyses were correlated with treatment, MPR and PD-L1 expression. Results: 116 patients have been enrolled as of October 31, 2018 and here we report on 54 of 180 planned pts with follow-up through surgery. 15 pts had Gr 3-4 AEs (3 treatment related), one Gr 5 AE (sudden death) was unrelated. By RECIST there were 3 PR, 49 SD, and 2 PD. 50/54 pts underwent the planned surgery, 47 pts had MPR assessment: 4 pts discontinued study preop (2 radiographic PD, 2 other reasons); 3 were unresectable. Excluding 5 pts with EGFR or ALK mutations, MPR rate was 10/45 (22%, 95% CI 11-37%). Baseline PD-L1 status was evaluable in 44/54 pts; BEP included 31 pts, 23 had tissue PD-L1 status: 16 PD-L1+. We observed significant increases in natural killer (NK) cells, CD8+ T-cells, Th1-response related dendritic cells (DC), and decreases in B-cells after atezo. Non-MPR pts showed significant increases in late activated NK cells, monocytic myeloid cells and Th2 and Th17-response–related DCs. PD-L1+ pts showed significant decreases of senescent T cells, monocytic myeloid cells, and increases of Th1-response–related DCs. We analyzed 22/54 tumor pairs, PD-L1+ cells increased in most pts after atezo treatment. Conclusions: Neoadjuvant atezo was well tolerated and the MPR rate is encouraging. Preliminary immunophenotyping data showed significant changes in PB with immunotherapy. Clinical trial information: NCT02927301.
A study of REGN3767, an anti-LAG-3 antibody, alone and in combination with cemiplimab (REGN2810), an anti-PD1 antibody in advanced cancers.
Authors: Papadopoulos Kyriakos P. , Lakhani Nehal , Johnson Melissa Lynne , Park Haeseong , Wang Ding , Yap Timothy A. , Moore Kathleen N. , Sims Tasha Nicholle , Emeremni Chetachi A. , Karasarides Maria , Kroog Glenn S.
Published: July 2019

TPS41

Background: Lymphocyte activation gene 3 (LAG-3) is an immune checkpoint receptor with a biological role in T-cell regulation. Analysis of immune-cell infiltrates from human tumors show that a subset of CD4+ and/or CD8+ cells co-express LAG-3 and PD-1 and may be associated with decreased T-cell effector function and tumor escape (Baitsch, 2011; Jie, 2013). Preclinical models provide evidence that dual inhibition of LAG-3 and PD-1 blockade offer synergistic anti-tumor effects and suggest a promising immunotherapy combination that warrants clinical investigation (Woo, 2012). This first in human study will evaluate the safety and efficacy of REGN3767 alone and in combination with cemiplimab in advanced malignancies. Methods: Phase 1 study enrolling patients with advanced malignancies. Dose escalation phase employs a modified 3+3 (4+3) design to assess the tolerability and pharmacokinetics (PK) of REGN3767 monotherapy and in combination with cemiplimab. Monotherapy and combination therapy are exploring multiple escalating REGN3767 dose levels. After tolerability and PK evaluation, doses of REGN3767 will be selected for monotherapy and combination therapy tumor-specific expansion cohorts. Solid tumor expansion cohorts will enroll per Simon’s two-stage design to evaluate safety and preliminary efficacy. Lymphoma expansion cohorts will enroll 15 patients. Patients who are anti-PD-1/PD-L1 therapy naïve and experienced are eligible for separate cohorts. Patients previously exposed to anti-LAG-3 therapy are not eligible. The primary objectives are the determination of the recommended dose for expansion (dose escalation) and ORR (dose expansion). Secondary objectives include characterization of PK and immunogenicity in all patients, as well as anti-tumor efficacy in dose escalation, and safety in dose expansion. This trial is actively enrolling eligible patients in the US, UK, Ireland, and South Korea. 1. Baitsch L et al. J Clin Investig. 2011;121:2350–2360. 2. Jie HB et al. Br J Cancer. 2013;109:2629–2635. 3. Woo SR et al. Cancer Res. 2012;72(4): 917–927. Clinical trial information: NCT03005782.
Phase I study of durvalumab and tremelimumab together with radiotherapy for the adjuvant treatment of intermediate-risk head and neck squamous cell carcinoma.
Authors: Sheth Siddharth , Chera Bhishamjit S. , Vincent Benjamin Garrett , Shen Colette J. , Weissler Mark Christian , Blumberg Jeffrey , Patel Samip , Zanation Adam M. , Yarbrough Wendell Gray , Patel Shetal Arvind , Grilley-Olson Juneko E. , Hackman Trevor , Weiss Jared
Published: July 2019

TPS73

Background: When surgery is used as the primary therapeutic modality for locally-advanced HNSCC, radiation therapy (XRT) is frequently recommended post-operatively due to high rates of recurrence. In high-risk patients; i.e., those with positive surgical margins or extra-nodal extension (ENE) on surgical pathology, the addition of chemotherapy to post-operative XRT (cCRT) provides a survival benefit. In contrast, there is no standard indication for adjuvant systemic therapy in intermediate risk HNSCC—defined in this study as having a T3/T4 primary tumor, perineural or lymphovascular space invasion, and/or lymph node metastasis without ENE. The anti-programmed cell death-ligand 1 (PD-L1) antibody durvalumab (D) has a manageable safety profile and encouraging clinical activity studies across multiple tumor types. Combining D with the anti-cytotoxic T-lymphocyte-associated antigen-4 (anti-CTLA-4) antibody tremelimumab (T) may amplify antitumor T-cell responses and provide synergistic activity. D+T showed antitumor activity and manageable tolerability in advanced NSCLC. Furthermore in preclinical studies, D+T combined with XRT decreased regulatory T-cells and myeloid derived suppressor cells and increased CD8 T-cell recruitment to the tumor microenvironment. Methods: This two-part phase I study will include a safety run-in period using a 3+3 dose de-escalation design based on dose limiting toxicities (DLT). In Cohort 1, D (q3 weeks) +T (q3 weeks) will be given on cycle 1 followed by concurrent XRT for Cycles 2-4. Cycle 5 and 6 will include D only. If DLT’s are met, Cohort -1 will include D (q3 weeks) and T (q6 weeks). If DLT's are found in Cohort -1, Cohort -2 would include only D. A dose expansion cohort (N=24) will follow based on the safest combination in the safety run-in. Translational studies include correlation of pre-treatment immune characteristics including PD-L1 score, TMB, and IFN-gamma signature with disease free survival. DNA and RNA sequencing of pre-treatment tissue and at treatment failure/recurrence will attempt to identify genetic and molecular determinants of IO treatment resistance. (NCT02000947). Clinical trial information: NCT03529422.