Clinical Trials of Vaccines for Biodefense and Emerging and Neglected Diseases

The development of safe and effective vaccines for the prevention and control of emerging and neglected infectious diseases is an international priority, as is the development of similar control measures for bioterrorist threats. International standards have been established to ensure the protection of human subjects and the scientific integrity of clinical trial study design and data collection. A general overview of the history of the regulatory guidelines and ethical principles underpinning the vaccine development process is provided, with an emphasis on clinical trials conducted in the United States. The contemporary vaccine development process involves sequential assessment of safety, immunogenicity, and efficacy in phase1, 2, and 3 clinical trials. The process is not always linear or straightforward, and adaptive flexible clinical trial designs can increase the likelihood of a successful outcome. Because the efficacy of vaccines for a number of the diseases discussed in this volume cannot be tested directly in humans, alternative approaches have been developed to address this challenge. The major elements of typical clinical trial protocol are discussed, and a checklist of essential documents supporting the trial is provided. As novel vaccine approaches and technologies emerge, the regulatory and ethical considerations will need to be revisited and adapted to respond to the ever-changing landscape.