Brief History of Clinical Trials on Viral Vaccines

Most viral vaccines were developed as a consequence of our ability to cultivate viruses in embryonated eggs (from the 1930s) or cell cultures (the 1950s and 1960s). Clinical trials on vaccines are classified as phase I, II, III, or IV, depending on the stage of clinical development of a vaccine. This article focuses on the clinical trials and future trends in the development of different kinds of vaccines. Keywords: viral vaccines; etiology; clinical trials; human immunodeficiency virus (HIV); vaccination programs