First clinical vaccination data has been obtained using an HSV vector expressing full length tyrosinase, gp100 and MART-1 to transduce DC from melanoma patients. Biovex has developed HSV-based vectors optimised for antigen delivery to dendritic cells by the deletion of HSV genes which usually inhibit DC function. These deliver antigens to DC at very high efficiency and activate the transduced cells similarly to LPS. Based on this technology, Biovex began a clinical program where an HSV vector expressing full length tyrosinase, gp100 and MART-1 was used to transdu...

We have data from a clinical trial with melanoma patients (stage IV, documented progress) receive DC transfected with RNA encoding MelanA, Mage3 and Survivin +/- E/L-selectin by the i.v. route. This DERMA-ER-DC 05 trial (multipeptide loaded cytokine matured moDC + prior Treg elimination by 3x ONTAK treatment [5µg/kg], 8 evaluated pat.) did not show any enhanced immune reponses compared to the equivalent cohort in the DERMA-ER-DC 04 trial. Patient recruitment into the 2nd phase of the DERMA-ER-DC 06 trial has started (sequential adaptive design). Immunomonitori...

We have obtained data from a phase I/II clinical trial of patients with end stage cervical cancer and of patients with vulvar intraepithelial neoplasia (VIN) grade III. Preclinical animal studies have shown that long peptides of 25-35 amino acids in length upon injection are only processed efficiently for MHC class I by dendritic cells in vivo. Long peptide injection is followed by appropriate cognate interactions between such DC, CD4+ T helper cells and CD8+ CTL precursors. Three groups of end stage cervical cancer patients (in total N=35) were subcutaneously va...

In our lab, data was obtained from a phase I trial using peptide-pulsed Dex. Dendritic cell (DC) derived-exosomes (Dex) are nanomeric vesicles harboring functional MHC/peptide complexes promoting T cell -dependent tumor rejection. In this Phase I trial using peptide-pulsed Dex, the observation of clinical regressions in the absence of T cell responses prompted the search for alternate effector mechanisms. Mouse studies unraveled the bioactivity of Dex onto NK cells, Dex promoting a IL-15Ra-dependent NK cell proliferation and a NKG2D-dependent activation resulting...

Our lab conducted an immunomonitoring study, such as on effector memory T cells, which led to corresponding immunological data.

Using the MLPC/tetramer method described last year, we obtained data by pursuing the immunological monitoring of melanoma patients vaccinated with 4 peptides (MAGE-A3, gp100, NA17 and tyrosinase) presented by HLA-A2. We measured responses to these peptides injected with Montanide, but did not know whether the Montanide adjuvant was important for these T cell responses. Indeed, melanoma patients may mount spontaneous responses to these antigenic peptides. We therefore injected the same peptides without adjuvant, and no response was observed. We conclude that Montan...

We are collecting immunological data from a melanoma patient, aiming to identify the antigen(s) recognized by T cells from this patient that experienced an outstanding response to immunotherapy. This patient received several adoptive T cell transfers and regressed from stage IV melanoma to a disease free state and has remained tumor free for several years. In a collaboration with Dr. O. Winqvist, Karolinska Institute, we attempted to improve the adoptive transfer protocol by stimulating T cells with monocyte derived DC pulsed with tumor lysate, instead of simply a...

Design of this trial: sequential adaptive design, 2nd cohort, mature DC transfected with RNA encoding MelanA, Mage3 and Survivin +/- E/L-selectin, i.v. route, 13 evaluated patients. Comparison of pre-existing and vaccine-induced immune responses in stage IV melanoma patients. We have efficiently transfected DC with RNA encoding a functional protein (E/L-selectin), which allows entry of DC into LN from HEV. These DC rolled in vitro on sialyl-LewisX-coated slides, and in vivo, mouse E/L-selectin-transfected DC homed to LN after i.v. application. Monocyte-derived and...

Our lab has data from an interim statistical analysis of the DERMA-ER-DC 04 trial (multipeptide loaded cytokine matured moDC +/- CD40L activation, 70 evaluated patients). This analysis for the first time showed a clinical correlation of induced immune responses as measured in the blood with outcome, as there have been so far statistically significantly less events in stage III patients showing good CTL reponses (IFN-y Elispot) to multiple class I and II peptides compared to low responders of the stage III cohort. Additional in vitro maturation of DC by CD40L (leuci...

We are planning clinical trials of melanoma patients treated with DC and tumour lysate plus adoptive transfer of T cells which will result in corresponding data.

Summary of the completed RCC clinical study and the data obtained: RCC subjects were deficient in T cell IFN-gamma and IL-2 production pre-vaccination. The IL-2 defect was corrected in 7/12 patients post-vaccination. Vaccination resulted in an increase in tumor antigen-specific T cells in 8/12 patients. 7/12 subjects had a response to more than one antigen post-vaccination. Median overall survival was ~25 months compared to ~11 months for historical controls (confirmed by matched pair analysis).

During the previous period we obtained data from our continued pilot clinical trials of DC-based immunotherapy of melanoma patients. After an initial cohort of patients treated with monocyte-derived DCs matured with inflammatory cytokines and subsequently electroporated with mRNA encoding 6 tumor-associated antigens, we persued this trial in a next cohort where DC-based vaccines were combined with low dose IFN-alfa (3 x 10e6 U per wk). In a significantly higher number of patients we observed vaccine-induced depigmentation and vitiligo. Further improvement and ca...

A phase I/II study of immunization of HIV infected individuals stable under HAART has been initiated which will provide us with immunological data. These patients are being vaccinated with cytokine cocktail matured DCs electroporated with mRNA encoding Tat, Rev and Nef. The cDNA’s encoding these early expressed HIV antigens have been human codon optimized and modified with lysosomal targeting sequences. Four vaccines separated by 4 weeks. Two weeks after the 4th vaccine, an analytical HAART interruption was started. So far, 17 patients have been included in t...

Our lab obtained data on the ability of NK cell IFN-gamma production to predict long term survival in advanced GISTs treated with IM. Background: Mutant isoforms of the KIT or PDGF receptors expressed by gastrointestinal stromal tumors (GISTs) are considered the therapeutic targets for imatinib mesylate (IM) (Gleevec®, Novartis), a specific inhibitor of these tyrosine kinase receptors. Predictive factors for the response to IM pertain to the intrinsic features of GIST tumor cells but not to the host. Besides its direct antiproliferative activity on tumor cells, I...

We have further data available on a clinical trial on vaccination of B-CLL patients with autologous, apoptotic, leukemic cells (Apo-DC). Cohort 1 with the vaccine alone and cohort 2 (5 patients) combining the vaccine together with GM-CSF as an adjuvant has finished accrual and all patients in these two cohorts have been monitored for 52 weeks. The clinical and immune monitoring data is being currently analyzed. The third cohort consisting of the vaccine and GM-CSF administered after a single dose of cyclophosphamide (300 mg/ sq. meter) is currently being accrued...

Data has been obtained in a study of antigen recognition of blood-derived T cells. In this study, an IFNgamma ELISPOT was done with PBMC loaded with peptide pools, each consisting of 10 15-mers, which overlap with 11 aminoacids.

We have obtained data from an analysis of antigen loading of DCs via targeting DC-SIGN, which resulted in enhanced class II-mediated presentation. Constructs for fusion proteins of the DC specific receptor DC-SIGN fused to GFP have been generated.

Data have been obtained on the antigen recognition of DTH infiltrating T cells. To obtain the data, activation of CD4 and CD8 T cells upon recognition of EBV-B cells expressing vaccinal antigens was evaluated by CD137 upregulation, CD107a and CD40L expression using flow cytometry. Luminex technology was used to quantify the TNFalpha and IFNgamma secretion.

At the end of 2004 BruCells has initiated two identical clinical studies entitled: “A Phase IB/II Study of Immunotherapy with Autologous Dendritic Cells Pulsed with Multiple HLA-A2 and MAGE-3.DP4 Peptides in Metastatic Cutaneous Melanoma Patients”. Patients received sequential immunizations with autologous dendritic cells pulsed with 8 HLA-restricted HLA-A2 peptides and a MAGE-3.DP4 peptide. They were randomized to receive immunizations either with I3 DC (DC generated with interferon-beta and interleukin-3) or with G4 DC (DC generated with GM-CSF and IL-4). At ...