José Luis Pérez Gracia, Carlos Alfaro Alegría, Alberto Benito Boillos, Álvaro González Hernández, Alfonso Gúrpide Ayarra, José María López Picazo, María Rodríguez Ruiz and Rafael Martínez Monge, Clínica Universidad de Navarra; Inmaculada Rodríguez López and Carmen Oñate Salafranca, Centro de Investigación Médica Aplicada.
Hiltonol (poly-ICLC) is an artificial synthetic molecule that mimics double-stranded RNA with a potent immune stimulatory activity through various mechanisms, including: induction of interferon-β/α and other cytokines; modulation of innate and adaptive immunity mechanism. In an ongoing clinical trial we are evaluating administration of intratumoral Hiltonol (thus avoiding systemic toxicity) with vaccination with dendritic cells (DC) that present tumor antigens, as a treatment for solid tumors (Clinicaltrials.gov NCT01734564). We are also characterizing the immunological effects of Hiltonol, including the maturation response of DC, cytokine production and immune reactions against tumor antigens. After having confirmed the safety with suggestive data on the efficacy of the combined treatment (two metabolic responses by PET in the first seven evaluable patients), we plan to assess the abscopal effect (induction of systemic responses by radiotherapy), adding a new cohort of patients to the ongoing protocol.