An attenuated strain of Mycobacterium bovis with non-specific immunoadjuvant and immunotherapeutic properties. Although the mechanism of its anti-tumor activity is unclear, immunization with BCG (Bacillus Calmette-Guerin) likely activates a Th1 cytokine response that includes induction of interferon. Vaccination with BCG may be immunoprotective against infection with Mycobacterium tuberculosis. (NCI04)