DIPG-08. PHASE IB IMMUNOTHERAPY CLINICAL TRIAL WITH THE USE OF AUTOLOGOUS DENDRITIC CELLS PULSED WITH AN ALLOGENIC TUMORAL CELL LINES LYSATE IN PATIENTS WITH NEWLY DIAGNOSED DIFFUSE INTRINSIC PONTINE GLIOMA (DIPG)

Abstract

Diffuse intrinsic pontine glioma (DIPG) is the most frequent brainstem tumor in children. DIPG is well characterized clinically, radiologically and more recently by specific molecular markers. Currently, there is no curative treatment for patients with DIPG. Focal irradiation is the only treatment that stops tumor progression-in most of patients- for a few months. However, the majority of patients with DIPG succumb to their disease during the first 2 years after diagnosis. Thus, novel and more efficacious therapeutic interventions are desperately needed. This Ib pilot study explores the use of immunotherapy with dendritic cells (DC) for the treatment of patients with newly diagnosed DIPG. In short, patient´s DC are extracted at diagnosis or after irradiation completion by leukapheresis and are primed with a tumoral lysate composed of 8 cell lines obtained from 5 patients with molecularly proved DIPG. This tumoral lysate offers a wide range of tumoral antigens specific for DIPG cells which will generate specific and non-specific antitumoral response when exposed to DC. The principal goal of this pilot study is to establish the feasibility and safety of the intradermic administration of DC vaccines in patients with DIPG after radiation therapy. Also, we will evaluate the non-specific and antitumoral immune response generated in serum/CSF, and if this response translates into clinical and/or radiologic response. Additionally, we will study if there is correlation between the immune response generated and improved overall survival for this cohort of patients. This pilot study is designed to include 10 patients. To date, 2 patients have been included and receiving therapy with no toxicity identified. Three more patients will be included within the next few weeks. We expect to have some of the data mentioned above by June 2017. We believe it is important to share these data with the pediatric neuro-oncology scientific community.