Concomitant combination of active immunotherapy and carboplatin- or paclitaxel-based chemotherapy improves anti-tumor response.

Recent preclinical evidence substantially supports the successful combination of chemotherapies and active immunotherapy for cancer treatment. These data sustain the effect of sequential combination schemes (vaccine plus chemotherapy or vice versa), which could be difficult to implement in clinical practice. Since chemotherapy is the standard treatment for most cancers, ethical issues forbid its delay and make difficult the evaluation of other treatments such as using an immunotherapeutic agent. Besides, vaccines must be applied as soon as possible to advanced cancer patients, in order to give them time to develop an effective immune response. Thus, a clinically attractive scenario is the concomitant application of treatments. However, little is known about the specific effect of different chemotherapeutic agents when combined with a cancer vaccine in such concomitant treatment. In this work, we analyze the influence of high-dose carboplatin or paclitaxel in the generation of a specific immune response when administered concomitantly with an OVA vaccine. Interestingly, neither carboplatin nor paclitaxel affects the humoral and CTL in vivo response generated by the vaccine. Moreover, an enhancement of the overall anti-tumor effect was observed in animals treated with OVA/CF vaccine combined with cytotoxic drugs. Moreover, the effect of the concomitant treatment was tested using a tumor-related antigen, the epidermal growth factor (EGF). Animals administered with EGF-P64k/Montanide and cytotoxic agents showed an antibody response similar to that from control animals. Therefore, our study suggests that carboplatin and paclitaxel can be concomitantly combined with active immunotherapies in the clinical practice of advanced cancer patients.