Lung cancer remains one of the leading causes of cancer-related deaths. Non-small cell lung cancer (NSCLC) is the most common histologic type of lung cancer. Medical and scientific progress has led to longer survival in an increasing number of patients suffering from cancer. Concerning patients with advanced NSCLC, there is a subgroup with long-term survival. The human epidermal growth factor receptor (EGFR) family plays a key role in tumor development. This cluster of genes is associated with augmented angiogenesis and enhanced proliferation, survival, and migration of tumor cells. The CIMAvax-EGF vaccine consists of a chemical conjugate of the EGF with the P64 protein derived from the Meningitis B bacteria and the Montanide ISA 51, as adjuvant. The vaccine induces antibodies against EGF that results in EGF withdrawal. CIMAvax-EGF has been demonstrated to be safe and immunogenic in advanced NSCLC patients. Here we summarize the current knowledge of the mechanism of action of CIMAvax-EGF, highlighting the impact of this anti-EGF-based vaccine on the long-term survival of advanced NSCLC patients.