Therapeutic vaccines in non-small cell lung cancer

Non-small cell lung cancer (NSCLC) unfortunately carries a very poor prognosis. Patients usually do not become symptomatic, and therefore do not seek treatment, until the cancer is advanced and it is too late to employ curative treatment options. New therapeutic options are urgently needed for NSCLC, because even current targeted therapies cure very few patients. Active immunotherapy is an option that is gaining more attention. A delicate and complex interplay exists between the tumor and the immune system. Solid tumors utilize a variety of mechanisms to evade immune detection. However, if the immune system can be stimulated to recognize the tumor as foreign, tumor cells can be specifically eliminated with little systemic toxicity. A number of vaccines designed to boost immunity against NSCLC are currently undergoing investigation in phase III clinical trials. Belagenpumatucel-L, an allogeneic cell vaccine that decreases transforming growth factor (TGF-β) in the tumor microenvironment, releases the immune suppression caused by the tumor and it has shown efficacy in a wide array of patients with advanced NSCLC. Melanoma-associated antigen A3 (MAGE-A3), an antigen-based vaccine, has shown promising results in MAGE-A3(+) NSCLC patients who have undergone complete surgical resection. L-BLP25 and TG4010 are both antigenic vaccines that target the Mucin-1 protein (MUC-1), a proto-oncogene that is commonly mutated in solid tumors. CIMAVax is a recombinant human epidermal growth factor (EGF) vaccine that induces anti-EGF antibody production and prevents EGF from binding to its receptor. These vaccines may significantly improve survival and quality of life for patients with an otherwise dismal NSCLC prognosis. This review is intended to give an overview of the current data and the most promising studies of active immunotherapy for NSCLC.