Zinecard

Administer ZINECARD Injection via intravenous infusion over 15 minutes. DO NOT ADMINISTER VIA AN INTRAVENOUS PUSH.

The recommended dosage ratio of ZINECARD to doxorubicin is 10:1 (e.g., 500 mg/m² ZINECARD to 50 mg/m² doxorubicin). Do not administer doxorubicin before ZINECARD. Administer doxorubicin within 30 minutes after the completion of ZINECARD infusion.

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

Only use ZINECARD in those patients who have received a cumulative doxorubicin dose of 300 mg/m² and are continuing with doxorubicin therapy. Do not use with chemotherapy initiation as ZINECARD 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 ZINECARD starting with their first cycle of FAC therapy, patients who were randomized to receive ZINECARD had a lower response rate (48% vs. 63%) and shorter time to progression than patients who were randomized to receive placebo.

Treatment with ZINECARD 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.

Secondary malignancies such as acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) have been reported in studies of pediatric patients who have received ZINECARD in combination with chemotherapy. ZINECARD is not indicated for use in pediatric patients. Some adult patients who received ZINECARD 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 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)].

ZINECARD 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)].

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 ZINECARD. The dose of doxorubicin was 50 mg/m² 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 ZINECARD experienced more severe leukopenia, granulocytopenia, and thrombocytopenia than patients receiving FAC without ZINECARD [see Warnings and Precautions (5.1)].

Table 1 below lists the incidence of adverse reactions for patients receiving FAC with either ZINECARD or placebo in the breast cancer studies. Adverse experiences occurring during courses 1 through 6 are displayed for patients receiving ZINECARD 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 ZINECARD 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 ZINECARD arm, as compared to placebo.

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.

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

Clinical studies of ZINECARD 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.

Greater exposure to dexrazoxane may occur in patients with compromised renal function. Reduce the ZINECARD 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 ZINECARD 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.

The pharmacokinetics of dexrazoxane have been studied in advanced cancer patients with normal renal and hepatic function. The pharmacokinetics of dexrazoxane can be adequately described by a two-compartment open model with first-order elimination. Dexrazoxane has been administered as a 15 minute infusion over a dose range of 60 to 900 mg/m² with 60 mg/m² of doxorubicin, and at a fixed dose of 500 mg/m² with 50 mg/m² doxorubicin. The disposition kinetics of dexrazoxane are dose-independent, as shown by linear relationship between the area under plasma concentration-time curves and administered doses ranging from 60 to 900 mg/m². The mean peak plasma concentration of dexrazoxane was 36.5 µg/mL at 15- minute after intravenous administration of 500 mg/m² dose of ZINECARD over 15 to 30 minutes prior to the 50 mg/m² doxorubicin dose.

The important pharmacokinetic parameters of dexrazoxane are summarized in Table 2:

No long-term carcinogenicity studies have been carried out with dexrazoxane in animals. Nevertheless, a study by the National Cancer Institute has reported that long-term dosing with razoxane (the racemic mixture of dexrazoxane, ICRF-187, and its enantiomer ICRF-186) is associated with the development of malignancies in rats and possibly in mice [see Warnings and Precautions (5.4)].

Dexrazoxane was not mutagenic in the bacterial reverse mutation (Ames) test, but was found to be clastogenic to human lymphocytes in vitro and to mouse bone marrow erythrocytes in vivo (micronucleus test).

ZINECARD has the potential to impair fertility in male patients based on effects in repeat-dose toxicology studies. Testicular atrophy was seen with dexrazoxane administration at doses as low as 30 mg/kg weekly for 6 weeks in rats (1/3 the human dose on a mg/m² basis) and as low as 20 mg/kg weekly for 13 weeks in dogs (approximately equal to the human dose on a mg/m² basis).

Store at 25°C (77°F); excursions permitted to 15° to 30°C (59° to 86°F) [see USP Controlled Room Temperature].

Follow special handling and disposal procedures.¹

Treatment with ZINECARD is associated with leukopenia, neutropenia, and thrombocytopenia. Perform hematological monitoring [see Warnings and Precautions (5.1)].

Counsel patients on pregnancy planning and prevention. Advise female patients of reproductive potential that ZINECARD can cause fetal harm and to use highly effective contraception during treatment [see Warnings and Precautions (5.5) and Use in Specific Populations (8.1, 8.6)].