Mitoxantrone is an example of a class of chemotherapeutic drugs called anthracyclines. Inside cancer cells, mitoxantrone binds to DNA and certain enzymes involved in the opening of DNA; cross-links strands of DNA; interferes with the repair of modified DNA; and blocks synthesis of DNA and RNA.
Some women with breast cancer of Stage IIIB and higher or recurrent breast cancer receive adjuvant (i.e., post-surgical) treatment with mitoxantrone alone or in combination with other types of chemotherapeutic drugs.
Although anthracyclines can be effective in the treatment of breast cancer, some anthracyclines (such as doxorubicin) pose a risk of cardiotoxic side effects (i.e., severe heart problems). Therefore, limited doses of certain anthracyclines (such as doxorubicin) typically are administered to patients.
Compared to doxorubicin, however, mitoxantrone causes fewer cardiotoxic side effects. Nevertheless, during treatment with any anthracycline, patients should be closely monitored for any heart problems.