Approaches to a vaccine against hepatitis A: development and manufacture of an inactivated vaccine.

The basis for the development of a vaccine against hepatitis A was laid in the 1970s, when virus was replicated in cell culture. Adaptation to growth in cell culture resulted in attenuation and sufficient quantities of virus particles, allowing the development of both live attenuated and inactivated vaccines. Testing of candidate vaccines in volunteers began in the early 1980s. Recently, a formaldehyde-inactivated whole-virion hepatitis A vaccine, the first licensed vaccine against hepatitis A, was introduced in many countries worldwide, and a live attenuated vaccine became available in the People's Republic of China. Other possible avenues for vaccine development include the use of either conventional or recombinant DNA techniques to obtain subunit vaccines, empty capsids, live viral or bacterial vectors, genetic immunization, synthetic peptides, and anti-idiotypes.