Overview of clinical studies with hepatitis B vaccine made by recombinant DNA.

The Merck, Sharp and Dohme hepatitis B vaccine formulated from HBsAg produced by a recombinant strain of Saccharomyces cerevisiae has proven to be highly immunogenic and safe. A 10 micrograms dose of the vaccine produced an anti-HBs response of greater than or equal to 10 IU/l in 91% or more of healthy adults who completed the three-dose regimen. Children responded well to all levels of vaccine antigen utilised but developed maximum anti-HBs titres with 5 micrograms doses. The age of the vaccine recipient affected responsiveness. Younger adults (20-29 years) responded more rapidly and with higher anti-HBs titres than did older adults (greater than or equal to 50 years). Children responded faster and with higher anti-HBs levels than younger adults. Clinical reactions reported after vaccination were mild and transient.