nw bio sitc poster 2014 v3.4 dw for...
TRANSCRIPT
![Page 1: NW Bio SITC Poster 2014 v3.4 DW for print...Ac#vated)Autologous)Dendri#c)Cells)injected)Intratumorally)are)Able)to)Overcome)) Local)and)Systemic)Immune)Suppression)Imposed)by)the)Tumor)Microenvironment](https://reader035.vdocuments.site/reader035/viewer/2022071405/60fb0454bd193b3f3f341aa9/html5/thumbnails/1.jpg)
Ac#vated Autologous Dendri#c Cells injected Intratumorally are Able to Overcome Local and Systemic Immune Suppression Imposed by the Tumor Microenvironment
Vivek Subbiah1, Ravi Murthy1, Robert Prins2, David S Hong1, Siqing Fu1, Aung Naing1, Anthony P. Conley1, Robert E. Brown3, Mary F. McGuire3, Chitra S Hosing1, Indresh Kaur1, Funda Meric-‐Bernstam1, Marnix Leo Bosch4
1The University of Texas MD Anderson Cancer Center, Houston, TX; 2UCLA, Los Angeles, CA; 3University of Texas Medical School at Houston, 4Northwest BiotherapeuHcs Inc, Bethesda, MD
ABSTRACT Introduc#on Cancer vaccines aiming to induce anH-‐tumor immune responses are generally considered most effecHve in an environment with minimal residual disease, due to the immunosuppressive effects exerted by most cancers. We hypothesized that appropriately acHvated autologous dendriHc cells (DCVax®-‐Direct) may be able to overcome this suppressive environment through the producHon of inflammatory cytokines and through the acHvaHon of signal transducHon pathways that condiHon the dendriHc cells for compleHon of the maturaHon processes even aWer intratumoral injecHon. Methods A Phase I trial that enrolled 36 paHents with diverse solid tumor cancers. Three intratumoral DCVax-‐Direct injecHons were given at Day 0, 7 and 14, followed by addiHonal injecHons at weeks 8, 16 and 32. PaHents were followed for safety parameters, for tumor response using appropriate imaging, and for pathological evaluaHon of tumor Hssue from serial biopsies. EvaluaHon of circulaHng immune cell populaHons as well as circulaHng cytokines is in progress. Results Recurrent low to moderate fevers were seen in most paHents following DCVax-‐Direct administraHon. SubstanHal increases in tumor size, were observed on CT or PET scans in the majority of paHents. InteresHngly, tumor biopsies of enlarged lesions demonstrated extensive tumor necrosis, as well as large immune cell accumulaHons, containing CD4+ and CD8+ T cells and other immune cells. In addiHon, these biopsies oWen showed paucity of tumor cells or, in some cases, no tumor cells were detected in the biopsies. In the one paHent assessed to date for circulaHng immune cells, a normalizaHon of the CD4:CD8 raHo was seen. Analysis of longer-‐term imaging data to assess tumor response is in progress. Conclusions Intra-‐tumoral injecHon of acHvated, autologous dendriHc cells is safe and feasible. The accumulaHon of immune cells in tumor biopsies suggests that these injecHons have the potenHal to successfully change the tumor microenvironment from immunosuppressive to one that is conducive to the inducHon of anH-‐tumor immune responses. NormalizaHon of the CD4:CD8 T cell raHo in circulaHon demonstrates the potenHal for systemic effects of this novel therapeuHc approach.
Pa#ent #1 – Dedifferen#ated Liposarcoma
Clinical History First diagnosis was in January of 2009. Prior treatments include radical resecHon, radiaHon therapy, and three lines of systemic (chemo-‐)therapy. Admission into DCVax-‐Direct trial in January of 2014, with progressive disease and lung metastases. Imaging Findings -‐ First re-‐staging scan at 8 weeks post the first DCVax-‐Direct
injecHon, the primary tumor mass shows interval increase in size, with increased bleeding and necrosis, suggesHng an anH-‐tumor effect of the dendriHc cell vaccine.
-‐ Subsequent scan at 16 weeks shows extensive intratumoral necrosis and a decrease in tumor size.
-‐ Next scan at 20 weeks shows a small increase in size and further intratumoral necrosis
Post contrast Axial T1 MRI of the proximal arm. Mul#ple scaYered areas of low signal intensity (red arrowheads) suggest intratumor necrosis interspersed within high signal intensity (green star) of residual tumor
These findings in response to treatment prompted further invesHgaHons into the mechanism of acHon of DCVax-‐Direct.
Tumor Biopsy Findings Tumor biopsies at week 8 showed extensive necrosis of the tumor Hssue, accumulaHon of immune cells, and moderate levels of infiltraHng T cells, approximately evenly divided between CD4+ and CD8+ T cells.
Pa#ent #1 – Dedifferen#ated Liposarcoma (cont.)
Morphoproteomic Analysis The use of bright field microscopy and immunohistochemistry directed against various protein analytes can beger define the biology of a tumor process and the pathogeneHc occurrences that might be responsible for its development, chemoradioresistance, and propensity to recur. To that end, we applied immunohisto-‐chemical probes against several protein analytes in secHons of the paHent's week 8 staging biopsy. One finding of interest was expression of T cell Intracellular AnHgen 1 (TIA-‐1), a protein involved in nucleolyHc acHvity against cytotoxic lymphocyte target cells. This expression appears to be largely associated with cells of the innate immune system (e.g. macrophages) and also with cells of the adapHve immune response (CD8+ T cells). T Cell Receptor Sequencing Comparison of shared TCRβ sequences between the tumor and peripheral blood at day 0 (Le^) and week 8 post DCVax-‐Direct (Right). Note the increase in shared TCRβ sequences at Week 8(>2x increase), sugges#ng that this pa#ent diversified the systemic an#-‐tumor T cell response following DC vaccina#on
Cytokine Analyses Preliminary results from sequenHal cytokine analyses show increases in interleukin-‐7 and -‐8, tumor necrosis factor alpha and type I and type II interferons, and decreases in macrophage derived chemokine as well as in macrophage inflammatory protein alpha. CollecHvely these changes suggest inducHon of a Th-‐1 type immune response. Circula#ng T cells Immunofluorescence of circulaHng T cells shows normalizaHon of the CD4:CD8 raHo over Hme, following DCVax-‐Direct injecHons.
Pa#ent #2 – Ovarian Cancer Clinical History IniHal diagnosis in 2002. Prior treatments include surgery and systemic treatment with anastrozole and with an experimental plaHnum compound. PaHent is admiged to the DCVax-‐Direct trial in July of 2014 with advanced, metastaHc ovarian cancer. Imaging Findings -‐ Restaging scan at 16 weeks post the first DCVax-‐Direct injecHon when compared to the week 8 images showed apparent mixed response to therapy, including reducHon in size of leW inguinal adenopathy, reducHon in size of subcutaneous lesions in the right anterior abdominal wall and an apparent new lesion in the leW lower anterior abdominal wall. Pre-‐DCVax-‐Direct Post-‐DCVax-‐Direct Tumor biopsy findings Tumor biopsies from week 8 showed infiltraHon of predominantly CD4+ cells as well as CD8+ cells in the lesion that had received 3 DCVax-‐Direct injecHons.
CD4