Immunization of cutaneous melanoma patients with the allogeneic cell vaccine CSF-470 enhances immune infiltration of metastatic lesions and would favor subsequent response to Vemurafenib

ARIS MARIANA; PAMPENA, MARÍA BETINA; LEVY, ESTRELLA MARIEL; BRAVO, ALICIA INÉS ; MADORSKY-ROWDO, FLORENCIA PAULA ; MORDOH, ANA ; KAPLAN, JULIO ; BARON, ANTONELA ; URRUTIA, MARIELA ; BLANCO, PAULA ALEJANDRA ; BARRIO, MARÍA MARCELA; MORDOH, JOSÉ

Orlando, FL

Conferencia; Tumor Immunology and Immunotherapy: A New Chapter.; 2014

Therapeutic cancer vaccines are aimed at promoting tumor specific immunity with long term memory. We have developed the CSF470 therapeutic vaccine, a mini allograft of four irradiated allogeneic cutaneous melanoma cell lines, combined with BCG and rhGM CSF as adjuvants; that is currently being assayed in adjuvancy against medium dose IFN alfa2b in the CASVAC0401 phase II/III clinical trial. An update to September 2014 reveals that after inclusion of 31 patients a significant benefit in the distant metastasis free survival for the CSF470 arm (p=0.034) is obtained. Of the 20 patients assigned to the CSF470 arm, with a mean follow up of 26 months, six patients developed distant metastases, of whom two died, and fourteen patients are distant metastases free (70%). Five patients of the vaccine arm were treated with Vemurafenib after progression; two of them achieved complete remission and two of them partial remission (>50%); only one developed severe dermatitis. Before Vemurafenib treatment, metastases biopsies from only three patients could be obtained; two of them later achieved complete responses. In this work we present the analysis of the peripheral blood and in situ immune populations during CSF470 immunization in the two patients that achieved complete responses with Vemurafenib treatment.