Recombinant BCG expressing Mycobacterium tuberculosis major extracellular proteins.

rBCG30, the first vaccine against tuberculosis demonstrated more potent than BCG in preclinical studies, is the prototype of a class of vaccines that utilize BCG as a host organism for expressing and secreting Mycobacterium tuberculosis major extracellular proteins. The vaccine is based on the concept that extracellular proteins of intracellular pathogens are key immunoprotective molecules. rBCG30, which expresses and secretes large amounts of the M. tuberculosis 30 kDa major secretory protein, is currently in human clinical trials.