An oligosaccharide anthracycline antineoplastic antibiotic isolated from the bacterium Streptomyces galilaeus. Aclarubicin intercalates into DNA and interacts with topoisomerases I and II, thereby inhibiting DNA replication and repair and RNA and protein synthesis. Aclarubicin is antagonistic to other agents that inhibit topoisomerase II, such as etoposide, teniposide and amsacrine. This agent is less cardiotoxic than doxorubicin and daunorubicin.