Chemotherapy combined with immunotherapy has improved the treatment of certain solid tumors, but effective regimens remain elusive for pancreatic ductal adenocarcinoma (PDAC). We conducted a randomized phase 2 trial evaluating the efficacy of nivolumab (nivo; anti-PD-1) and/or sotigalimab (sotiga; CD40 agonistic antibody) with gemcitabine/nab-paclitaxel (chemotherapy) in patients with first-line metastatic PDAC (NCT03214250). In 105 patients analyzed for efficacy, the primary endpoint of 1-year overall survival (OS) was met for nivo/chemo (57.7%, P = 0.006 compared to historical 1-year OS of 35%, n = 34) but was not met for sotiga/chemo (48.1%, P = 0.062, n = 36) or sotiga/nivo/chemo (41.3%, P = 0.223, n = 35). Secondary endpoints were progression-free survival, objective response rate, disease control rate, duration of response and safety. Treatment-related adverse event rates were similar across arms. Multi-omic circulating and tumor biomarker analyses identified distinct immune signatures associated with survival for nivo/chemo and sotiga/chemo. Survival after nivo/chemo correlated with a less suppressive tumor microenvironment and higher numbers of activated, antigen-experienced circulating T cells at baseline. Survival after sotiga/chemo correlated with greater intratumoral CD4 T cell infiltration and circulating differentiated CD4 T cells and antigen-presenting cells. A patient subset benefitting from sotiga/nivo/chemo was not identified. Collectively, these analyses suggest potential treatment-specific correlates of efficacy and may enable biomarker-selected patient populations in subsequent PDAC chemoimmunotherapy trials.

Background Cancer vaccines are designed to promote systemic antitumor immunity and tumor eradication. Cancer vaccination may be more efficacious in combination with additional interventions that may build on or amplify their effects. Methods Based on our previous clinical and in vitro studies, we designed an antigen-engineered DC vaccine trial to promote a polyclonal CD8 + and CD4 + T cell response against three shared melanoma antigens. The 35 vaccine recipients were then randomized to receive one month of high-dose IFNα or observation. Results The resulting clinical outcomes were 2 partial responses, 8 stable disease and 14 progressive disease among patients with measurable disease using RECIST 1.1, and, of 11 surgically treated patients with no evidence of disease (NED), 4 remain NED at a median follow-up of 3 years. The majority of vaccinated patients showed an increase in vaccine antigen-specific CD8 + and CD4 + T cell responses. The addition of IFNα did not appear to improve immune or clinical responses in this trial. Examination of the DC vaccine profiles showed that IL-12p70 secretion did not correlate with immune or clinical responses. In depth immune biomarker studies support the importance of circulating Treg and MDSC for development of antigen-specific T cell responses, and of circulating CD8 + and CD4 + T cell subsets in clinical responses. Conclusions DC vaccines are a safe and reliable platform for promoting antitumor immunity. This combination with one month of high dose IFNα did not improve outcomes. Immune biomarker analysis in the blood identified several predictive and prognostic biomarkers for further analysis, including MDSC. Trial registration NCT01622933 . Electronic supplementary material The online version of this article (10.1186/s40425-019-0552-x) contains supplementary material, which is available to authorized users.

BackgroundA first-in-human, randomized pilot phase II clinical trial combining vaccines targeting overexpressed, non-mutated tumor blood vessel antigens (TBVA) and tyrosine kinase inhibitor dasatinib was conducted in human leukocyte antigen (HLA)-A2+ patients with advanced melanoma.MethodsPatient monocyte-derived type-1-polarized dendritic cells were loaded with HLA-A2-presented peptides derived from TBVA (DLK1, EphA2, HBB, NRP1, RGS5, TEM1) and injected intradermally as a vaccine into the upper extremities every other week. Patients were randomized into one of two treatment arms receiving oral dasatinib (70 mg two times per day) beginning in week 5 (Arm A) or in week 1 (Arm B). Trial endpoints included T cell response to vaccine peptides (interferon-γ enzyme-linked immunosorbent spot), objective clinical response (Response Evaluation Criteria in Solid Tumors V.1.1) and exploratory tumor, blood and serum profiling of immune-associated genes/proteins.ResultsSixteen patients with advanced-stage cutaneous (n=10), mucosal (n=1) or uveal (n=5) melanoma were accrued, 15 of whom had previously progressed on programmed cell death protein 1 (PD-1) blockade. Of 13 evaluable patients, 6 patients developed specific peripheral blood T cell responses against ≥3 vaccine-associated peptides, with further evidence of epitope spreading. All six patients with specific CD8+ T cell response to vaccine-targeted antigens exhibited evidence of T cell receptor (TCR) convergence in association with preferred clinical outcomes (four partial response and two stabilization of disease (SD)). Seven patients failed to respond to vaccination (one SD and six progressive disease). Patients in Arm B (immediate dasatinib) outperformed those in Arm A (delayed dasatinib) for immune response rate (IRR; 66.7% vs 28.6%), objective response rate (ORR) (66.7% vs 0%), overall survival (median 15.45 vs 3.47 months; p=0.0086) and progression-free survival (median 7.87 vs 1.97 months; p=0.063). IRR (80% vs 25%) and ORR (60% vs 12.5%) was greater for females versus male patients. Tumors in patients exhibiting response to treatment displayed (1) evidence of innate and adaptive immune-mediated inflammation and TCR convergence at baseline, (2) on-treatment transcriptional changes associated with reduced hypoxia/acidosis/glycolysis, and (3) increased inflammatory immune cell infiltration and tertiary lymphoid structure neogenesis.ConclusionsCombined vaccination against TBVA plus dasatinib was safe and resulted in coordinating immunologic and/or objective clinical responses in 6/13 (46%) evaluable patients with melanoma, particularly those initiating treatment with both agents.Trial registration numberNCT01876212.

Background Various proinflammatory cytokines can be detected within the melanoma tumor microenvironment. Interleukin 32 (IL32) is produced by T cells, NK cells and monocytes/macrophages, but also by a subset of melanoma cells. We sought to better understand the biology of IL32 in human melanoma. Methods We analyzed RNA sequencing data from 53 in-house established human melanoma cell lines and 479 melanoma tumors from The Cancer Genome Atlas dataset. We evaluated global gene expression patterns associated with IL32 expression. We also evaluated the impact of proinflammatory molecules TNFα and IFNγ on IL32 expression and dedifferentiation in melanoma cell lines in vitro. In order to study the transcriptional regulation of IL32 in these cell lines, we cloned up to 10.5 kb of the 5′ upstream region of the human IL32 gene into a luciferase reporter vector. Results A significant proportion of established human melanoma cell lines express IL32, with its expression being highly correlated with a dedifferentiation genetic signature (high AXL/low MITF). Non IL32-expressing differentiated melanoma cell lines exposed to TNFα or IFNγ can be induced to express the three predominant isoforms (α, β, γ) of IL32. Cis -acting elements within this 5′ upstream region of the human IL32 gene appear to govern both induced and constitutive gene expression. In the tumor microenvironment, IL32 expression is highly correlated with genes related to T cell infiltration, and also positively correlates with high AXL/low MITF dedifferentiated gene signature. Conclusions Expression of IL32 in human melanoma can be induced by TNFα or IFNγ and correlates with a treatment-resistant dedifferentiated genetic signature. Constitutive and induced expression are regulated, in part, by cis -acting sequences within the 5′ upstream region. Electronic supplementary material The online version of this article (10.1186/s12967-019-1862-y) contains supplementary material, which is available to authorized users.

Therapeutic cancer vaccines targeting melanoma-associated antigens are commonly immunogenic but are rarely effective in promoting objective clinical responses. To identify critical molecules for activation of effective antitumor immunity, we have profiled autologous dendritic cell (DC) vaccines used to treat 35 patients with melanoma. We showed that checkpoint molecules induced by ex vivo maturation correlated with in vivo DC vaccine activity. Melanoma patient DCs had reduced expression of cell surface inducible T-cell costimulator ligand (ICOSL) and had defective intrinsic NF-κB signaling. Chromatin immunoprecipitation assays revealed NF-κB–dependent transcriptional regulation of ICOSL expression by DCs. Blockade of ICOSL on DCs reduced priming of antigen-specific CD8+ and CD4+ T cells from naïve donors in vitro. Concentration of extracellular/soluble ICOSL released from vaccine DCs positively correlated with patient clinical outcomes, which we showed to be partially regulated by ADAM10/17 sheddase activity. These data point to the critical role of canonical NF-κB signaling, the regulation of matrix metalloproteinases, and DC-derived ICOSL in the specific priming of cognate T-cell responses in the cancer setting. This study supports the implementation of targeted strategies to augment these pathways for improved immunotherapeutic outcomes in patients with cancer.