Safety and efficacy of a genetic vaccine targeting telomerase plus chemotherapy for B-cell canine lymphoma therapy

Background. We have recently shown that a genetic vaccine targeting dog telomerase (dTERT) and based on Ad/DNA-EP technology can induce strong immune response and increased overall survival of dogs affected by B-cell malignant lymphoma (ML) in comparison with historical controls when combined with COP chemotherapy regimen. Objectives. Here, we have conducted a double arm clinical trial including 21 dogs for each arm, (vaccine vs. control), measured the antigen-specific immune response and evaluated potential toxic effects of the immunotherapy along with following patients survival for three years and half. Methods: Changes in hematological parameters, local/systemic toxicity or organic dysfunction and fever were monitored over time during the treatment. The immune response was measured by ELISPOT. Results. No adverse effects attributable to treatment were observed in any dog patient. dTERT- specific immune response was induced in 19 of 21 treated animals. The overall survival time of vaccine/COP treated dogs was significantly increased over contemporaneous COP-treated animals (>76.1 vs 29.3 weeks, respectively, p