Survival by stage and tumor measurability in metastatic melanoma patients treated with autologous dendritic cell tumor cell vaccines.

Robert O. Dillman AIVITA Biomedical, Irvine, CA info_outline Robert O. Dillman, Andrew N Cornforth, Edward Francis McClay, Carol DePriest

Authors Robert O. Dillman AIVITA Biomedical, Irvine, CA info_outline Robert O. Dillman, Andrew N Cornforth, Edward Francis McClay, Carol DePriest Organizations AIVITA Biomedical, Irvine, CA, TCR2 Therapeutics, Cambridge, MA, Melanoma Research Center of San Diego, Encinitas, CA, Cancer Biotherapy Research Group, Franklin, TN Abstract Disclosures Research Funding Other Foundation Background: Survival of cancer patients is greatly affected by stage and tumor burden. The purpose of this study was to determine survival for melanoma patients who were treated with patient specific vaccines in the context of prospective clinical trials, by cohorts defined by stage and tumor measurability. Methods: Metastatic melanoma patients were treated with autologous dendritic cells loaded with antigens from irradiated cells from short-term autologous tumor cell lines (DCV). All patients had a metastatic melanoma lesion surgically resected, from which a tumor cell line was established. Irradiated tumor cells (ITC) were incubated with autologous dendritic cells (DC) to produce the DCV, which were injected s.c. in 500 micrograms GM-CSF weekly x 3 weeks, then monthly for 5 months. Data was pooled for DCV-treated patients enrolled in either of two phase II trials: one single-arm (NCT00948480), one randomized (NCT00436930). Patients were assigned to one of three cohorts based on their most advanced stage of disease prior to treatment, and whether they had measurable disease at the time of treatment. Survival was determined per Kaplan and Meier. Results: The final therapeutic products consisted of autologous DC with non-phagocytosed ITC making up 0% to 20% of cells in the final product. There were 45 men and 27 women. Median age was 52 years (range 17 to 83). Tumor sources were 37-lymph node, 20-viscera, and 15-soft tissue. No patients were lost to follow up; all surviving patients were followed 5 years. Toxicity was minimal. Median overall survival (OS) for all 72 patients was 49.4 mos; 5-year OS 46%. There was no correlation between survival and the number of DC or ITC in the first three injections. Patients with recurrent stage 3 disease that had not recurred (n=18) had a 72% 5-year OS; patients with non-measurable stage 4 (n=30) had a 53% 5-year OS. Patients with measurable stage 4 (n=18) had received an average of four prior therapies. They had a median OS of 18.5 months, and 2-year OS of 46%. Conclusions: This patient-specific DCV was associated with encouraging survival in all three clinical subsets. Because of its mechanism of action and absence of toxicity, it should be evaluated further. Clinical trial information: NCT00948480, NCT00436930