The goals of the various clinical trials were to demonstrate the safety and tolerability of the candidate vaccines, and to explore the efficacy of DNA vaccines in humans. Injection of the plasmid DNA construct is tolerated well in terms of safety in the patient population and rarely involves systemic toxicities. DNA vaccines that are currently being tested do not show relevant levels of integration into host cellular DNA [139, 140] . Besides, preclinical studies in nonhuman primates as well as early studies in humans did not detect increases in antinuclear or anti-DNA antibodies. Participants in human trials of DNA vaccines are followed for possible signs and symptoms of autoimmunity induced by DNA vaccination giving no convincing evidence of autoimmunity developing in association with a DNA vaccine [40, 42, 141] .