Mitoxantrone

Mitoxantrone injection, USP (concentrate) is indicated for reducing neurologic disability and/or the frequency of clinical relapses in patients with secondary (chronic) progressive, progressive relapsing, or worsening relapsing-remitting multiple sclerosis (i.e., patients whose neurologic status is significantly abnormal between relapses). Mitoxantrone injection, USP (concentrate) is not indicated in the treatment of patients with primary progressive multiple sclerosis. The clinical patterns of multiple sclerosis in the studies were characterized as follows: secondary progressive and progressive relapsing disease were characterized by gradual increasing disability with or without superimposed clinical relapses, and worsening relapsing-remitting disease was characterized by clinical relapses resulting in a step-wise worsening of disability.

Mitoxantrone, a DNA-reactive agent that intercalates into deoxyribonucleic acid (DNA) through hydrogen bonding, causes crosslinks and strand breaks. Mitoxantrone also interferes with ribonucleic acid (RNA) and is a potent inhibitor of topoisomerase II, an enzyme responsible for uncoiling and repairing damaged DNA. It has a cytocidal effect on both proliferating and nonproliferating cultured human cells, suggesting lack of cell cycle phase specificity. Mitoxantrone injection has been shown in vitro to inhibit B cell, T cell, and macrophage proliferation and impair antigen presentation, as well as the secretion of interferon gamma, TNFα, and IL-2.

Multiple Sclerosis The recommended dosage of mitoxantrone injection (concentrate) is 12 mg/m 2 given as a short (approximately 5 to 15 minutes) intravenous infusion every 3 months. Left ventricular ejection fraction (LVEF) should be evaluated by echocardiogram or MUGA prior to administration of the initial dose of mitoxantrone injection (concentrate) and all subsequent doses. In addition, LVEF evaluations are recommended if signs or symptoms of congestive heart failure develop at any time during treatment with mitoxantrone injection (concentrate). Mitoxantrone injection (concentrate) should not be administered to multiple sclerosis patients with an LVEF < 50%, with a clinically significant reduction in LVEF, or to those who have received a cumulative lifetime dose of > 140 mg/m 2.

Mitoxantrone injection (concentrate) is contraindicated in patients who have demonstrated prior hypersensitivity to it.

WARNING Mitoxantrone injection (concentrate) should be administered under the supervision of a physician experienced in the use of cytotoxic chemotherapy agents. Mitoxantrone injection (concentrate) should be given slowly into a freely flowing intravenous infusion. It must never be given subcutaneously, intramuscularly, or intra-arterially. Severe local tissue damage may occur if there is extravasation during administration. WHEN MITOXANTRONE INJECTION IS USED IN HIGH DOSES (> 14 mg/m 2 /d × 3 days) SUCH AS INDICATED FOR THE TREATMENT OF LEUKEMIA, SEVERE MYELOSUPPRESSION WILL OCCUR. THEREFORE, IT IS RECOMMENDED THAT MITOXANTRONE INJECTION BE ADMINISTERED ONLY BY PHYSICIANS EXPERIENCED IN THE CHEMOTHERAPY OF THIS DISEASE. LABORATORY AND SUPPORTIVE SERVICES MUST BE AVAILABLE FOR HEMATOLOGIC AND CHEMISTRY MONITORING AND ADJUNCTIVE THERAPIES, INCLUDING ANTIBIOTICS.

Multiple Sclerosis Mitoxantrone injection has been administered to 149 patients with multiple sclerosis in two randomized clinical trials, including 21 patients who received mitoxantrone injection in combination with corticosteroids. In Study 1, the proportion of patients who discontinued treatment due to an adverse event was 9.7% (n = 6) in the 12 mg/m 2 mitoxantrone injection arm (leukopenia, depression, decreased LV function, bone pain and emesis, renal failure, and one discontinuation to prevent future complications from repeated urinary tract infections) compared to 3.1% (n = 2) in the placebo arm (hepatitis and myocardial infarction). The following clinical adverse experiences were significantly more frequent in the mitoxantrone injection groups: nausea, alopecia, urinary tract infection, and menstrual disorders, including amenorrhea.

Mitoxantrone and its metabolites are excreted in bile and urine, but it is not known whether the metabolic or excretory pathways are saturable, may be inhibited or induced, or if mitoxantrone and its metabolites undergo enterohepatic circulation. To date, postmarketing experience has not revealed any significant drug interactions in patients who have received mitoxantrone injection for treatment of cancer. Information on drug interactions in patients with multiple sclerosis is limited. Following concurrent administration of mitoxantrone injection with corticosteroids, no evidence of drug interactions has been observed.

Mitoxantrone injection, USP (concentrate) should be stored at 20° to 25°C (68° to 77°F). DO NOT FREEZE.