Dexrazoxane

Dexrazoxane for injection is indicated for reducing the incidence and severity of cardiomyopathy associated with doxorubicin administration in women with metastatic breast cancer who have received a cumulative doxorubicin dose of 300 mg/m 2 and who will continue to receive doxorubicin therapy to maintain tumor control. Do not use with the initiation of doxorubicin therapy [see Warnings and Precautions (5.2) ] . Dexrazoxane for injection is a cytoprotective agent indicated for reducing the incidence and severity of cardiomyopathy associated with doxorubicin administration in women with metastatic breast cancer who have received a cumulative doxorubicin dose of 300 mg/m 2 and who will continue to receive doxorubicin therapy to maintain tumor control. Do not use dexrazoxane for injection with doxorubicin initiation.

Dexrazoxane for injection is available in 250 mg single-dose vial as sterile, pyrogen-free lyophilizates. 250 mg single-dose vial as sterile, pyrogen-free lyophilizates.

Do not use dexrazoxane for injection with non-anthracycline chemotherapy regimens. Dexrazoxane for injection should not be used with non-anthracycline chemotherapy regimens.

Myelosuppression: Dexrazoxane may increase the myelosuppresive effects of chemotherapeutic agents. Perform hematological monitoring. ( 5.1 ) Embryo-Fetal Toxicity: Can cause fetal harm. Advise female patients of reproductive potential of the potential hazard to the fetus. ( 5.5 , 8.1 )

5.1 Myelosuppression Dexrazoxane may add to the myelosuppression caused by chemotherapeutic agents. Obtain a complete blood count prior to and during each course of therapy, and administer dexrazoxane and chemotherapy only when adequate hematologic parameters are met.

5.2 Concomitant Chemotherapy Only use dexrazoxane in those patients who have received a cumulative doxorubicin dose of 300 mg/m 2 and are continuing with doxorubicin therapy. Do not use with chemotherapy initiation as dexrazoxane may interfere with the antitumor activity of the chemotherapy regimen. In a trial conducted in patients with metastatic breast cancer who were treated with fluorouracil, doxorubicin, and cyclophosphamide (FAC) with or without dexrazoxane starting with their first cycle of FAC therapy, patients who were randomized to receive dexrazoxane had a lower response rate (48% vs. 63%) and shorter time to progression than patients who were randomized to receive placebo.

5.3 Cardiac Toxicity Treatment with dexrazoxane does not completely eliminate the risk of anthracycline-induced cardiac toxicity. Monitor cardiac function before and periodically during therapy to assess left ventricular ejection fraction (LVEF). In general, if test results indicate deterioration in cardiac function associated with doxorubicin, the benefit of continued therapy should be carefully evaluated against the risk of producing irreversible cardiac damage.

5.4 Secondary Malignancies Secondary malignancies such as acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) have been reported in studies of pediatric patients who have received dexrazoxane in combination with chemotherapy. Dexrazoxane for injection is not indicated for use in pediatric patients. Some adult patients who received dexrazoxane in combination with anti-cancer agents known to be carcinogenic have also developed secondary malignancies, including AML and MDS. Razoxane is the racemic mixture, of which dexrazoxane is the S(+)-enantiomer. Secondary malignancies (primarily acute myeloid leukemia) have been reported in patients treated chronically with oral razoxane. In these patients, the total cumulative dose of razoxane ranged from 26 grams to 480 grams and the duration of treatment was from 42 to 319 weeks. One case of T-cell lymphoma, one case of B-cell lymphoma, and six to eight cases of cutaneous basal cell or squamous cell carcinoma have also been reported in patients treated with razoxane. Long-term administration of razoxane to rodents was associated with the development of malignancies [see Nonclinical Toxicology (13.1) ] .

5.5 Embryo-Fetal Toxicity Dexrazoxane can cause fetal harm when administered to pregnant women. Dexrazoxane administration during the period of organogenesis resulted in maternal toxicity, embryotoxicity and teratogenicity in rats and rabbits at doses significantly lower than the clinically recommended dose [see Use in Specific Populations (8.1) ] . If this drug is used during pregnancy, or if the patient becomes pregnant while taking this drug, the patient should be apprised of the potential hazard to a fetus. Advise female patients of reproductive potential to avoid becoming pregnant and to use highly effective contraception during treatment [see Use in Specific Populations (8.6) ] .

In clinical studies, dexrazoxane was administered to patients also receiving chemotherapeutic agents for cancer. Pain on injection was observed more frequently in patients receiving dexrazoxane versus placebo. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Eugia US LLC at 1-866-850-2876 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch .

6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, the adverse reaction rates observed cannot be directly compared to rates in other trials and may not reflect the rates observed in clinical practice. The adverse reaction profile described in this section was identified from randomized, placebo-controlled, double-blind studies in patients with metastatic breast cancer who received the combination of the FAC chemotherapy regimen with or without dexrazoxane. The dose of doxorubicin was 50 mg/m 2 in each of these trials. Treatment was administered every three weeks until disease progression or cardiac toxicity. Patients in clinical trials who received FAC with dexrazoxane experienced more severe leukopenia, granulocytopenia, and thrombocytopenia than patients receiving FAC without dexrazoxane [see Warnings and Precautions (5.1) ] . Table 1 below lists the incidence of adverse reactions for patients receiving FAC with either dexrazoxane or placebo in the breast cancer studies. Adverse experiences occurring during courses 1 through 6 are displayed for patients receiving dexrazoxane or placebo with FAC beginning with their first course of therapy (columns 1 and 3, respectively). Adverse experiences occurring at course 7 and beyond for patients who received placebo with FAC during the first six courses and who then received either dexrazoxane or placebo with FAC are also displayed (columns 2 and 4, respectively). The adverse reactions listed below in Table 1 demonstrate that the frequency of adverse reaction “Pain on Injection” has been greater for dexrazoxane arm, as compared to placebo. Table 1: Adverse Reaction Percentage (%) of Breast Cancer Patients with Adverse Reaction FAC + Dexrazoxane FAC + Placebo Courses 1 to 6 N = 413 Courses ≥ 7 N = 102 Courses 1 to 6 N = 458 Courses ≥ 7 N = 99 Alopecia 94 100 97 98 Nausea 77 51 84 60 Vomiting 59 42 72 49 Fatigue/Malaise 61 48 58 55 Anorexia 42 27 47 38 Stomatitis 34 26 41 28 Fever 34 22 29 18 Infection 23 19 18 21 Diarrhea 21 14 24 7 Pain on Injection 12 13 3 0 Sepsis 17 12 14 9 Neurotoxicity 17 10 13 5 Streaking/Erythema 5 4 4 2 Phlebitis 6 3 3 5 Esophagitis 6 3 7 4 Dysphagia 8 0 10 5 Hemorrhage 2 3 2 1 Extravasation 1 3 1 2 Urticaria 2 2 2 0 Recall Skin Reaction 1 1 2 0

No drug interactions have been identified [see Clinical Pharmacology (12.3) ] .

Nursing Mothers: Discontinue drug or nursing. ( 8.3 )

8.1 Pregnancy Risk Summary Dexrazoxane can cause fetal harm when administered to pregnant women. Dexrazoxane administration resulted in maternal toxicity, embryotoxicity and teratogenicity in rats and rabbits at doses significantly lower than the clinically recommended dose. If this drug is used during pregnancy, or if the patient becomes pregnant while taking this drug, the patient should be apprised of the potential hazard to a fetus [see Warnings and Precautions (5.5) ] . Animal Data Dexrazoxane resulted in maternal toxicity in rats at doses of ≥ 2 mg/kg (1/40 the human dose on a mg/m 2 basis) and embryotoxicity and teratogenicity at 8 mg/kg (approximately 1/10 the human dose on a mg/m 2 basis) when given daily to pregnant rats during the period of organogenesis. Teratogenic effects in the rat included imperforate anus, microphthalmia, and anophthalmia. In offspring allowed to develop to maturity, fertility was impaired in the male and female rats treated in utero during organogenesis at 8 mg/kg. In rabbits, doses of ≥ 5 mg/kg (approximately 1/10 the human dose on a mg/m 2 basis) daily during the period of organogenesis caused maternal toxicity and doses of 20 mg/kg (1/2 the human dose on a mg/m 2 basis) were embryotoxic and teratogenic. Teratogenic effects in the rabbit included several skeletal malformations such as short tail, rib and thoracic malformations, and soft tissue variations including subcutaneous, eye and cardiac hemorrhagic areas, as well as agenesis of the gallbladder and of the intermediate lobe of the lung.

8.3 Nursing Mothers It is not known whether dexrazoxane or its metabolites are excreted in human milk. Because many drugs are excreted in human milk and because of the potential for serious adverse reactions in nursing infants from dexrazoxane, a decision should be made whether to discontinue nursing or discontinue the drug, taking into account the importance of the drug to the mother.

8.4 Pediatric Use The safety and effectiveness of dexrazoxane in pediatric patients have not been established [see Warnings and Precautions (5.4) ] .

8.5 Geriatric Use Clinical studies of dexrazoxane did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently than younger subjects. Other reported clinical experience has not identified differences in responses between the elderly and younger patients. In general, dose selection for an elderly patient should be cautious, usually starting at the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant disease or other drug therapy.

8.6 Females of Reproductive Potential Contraception: Dexrazoxane can cause fetal harm when administered during pregnancy. Advise female patients of reproductive potential to use highly effective contraception during treatment [see Use in Specific Populations (8.1) ] .

8.7 Renal Impairment Greater exposure to dexrazoxane may occur in patients with compromised renal function. Reduce the dexrazoxane dose by 50% in patients with creatinine clearance values < 40 mL/min [see Dosage and Administration (2.2) and Clinical Pharmacology (12.3) ] .

The mechanism by which dexrazoxane exerts its cytoprotective activity is not fully understood. Dexrazoxane is a cyclic derivative of EDTA that penetrates cell membranes. Results of laboratory studies suggest that dexrazoxane is converted intracellularly to a ring-opened chelating agent that interferes with iron-mediated free radical generation thought to be responsible, in part, for anthracycline-induced cardiomyopathy.