Intravenous Dosing

MESNEX may be given on a fractionated dosing schedule of three bolus intravenous injections as outlined below.

MESNEX injection is given as intravenous bolus injections in a dosage equal to 20% of the ifosfamide dosage weight by weight (w/w) at the time of ifosfamide administration and 4 and 8 hours after each dose of ifosfamide. The total daily dose of MESNEX is 60% of the ifosfamide dose. The recommended dosing schedule is outlined below in Table 1.

Intravenous and Oral Dosing

MESNEX may be given on a fractionated dosing schedule of a single bolus injection followed by two oral administrations of MESNEX tablets as outlined below.

MESNEX injection is given as intravenous bolus injections in a dosage equal to 20% of the ifosfamide dosage (w/w) at the time of ifosfamide administration. MESNEX tablets are given orally in a dosage equal to 40% of the ifosfamide dose 2 and 6 hours after each dose of ifosfamide. The total daily dose of MESNEX is 100% of the ifosfamide dose. The recommended dosing schedule is outlined in Table 2.

The efficacy and safety of this ratio of intravenous and oral MESNEX has not been established as being effective for daily doses of ifosfamide higher than 2 g/m2.

Patients who vomit within two hours of taking oral MESNEX should repeat the dose or receive intravenous MESNEX.

Monitoring for Hematuria

Maintain adequate hydration and sufficient urinary output, as required for ifosfamide treatment, and monitor urine for the presence of hematuria. If severe hematuria develops when MESNEX is given according to the recommended dosage schedule, dosage reductions or discontinuation of ifosfamide therapy may be required.

Preparation for Intravenous Administration and Stability

Preparation

Determine the volume of MESNEX injection for the intended dose.

Dilute the volume of MESNEX injection for the dose in any of the following fluids to obtain a final concentration of 20 mg/mL:

•

5% Dextrose Injection, USP

•

5% Dextrose and 0.2% Sodium Chloride Injection, USP

•

5% Dextrose and 0.33% Sodium Chloride Injection, USP

•

5% Dextrose and 0.45% Sodium Chloride Injection, USP

•

0.9% Sodium Chloride Injection, USP

•

Lactated Ringer’s Injection, USP

Stability

The MESNEX injection multidose vials may be stored and used for up to 8 days after initial puncture.

Store diluted solutions at 25°C (77°F). Use diluted solutions within 24 hours.

Do not mix MESNEX injection with epirubicin, cyclophosphamide, cisplatin, carboplatin, and nitrogen mustard.

The benzyl alcohol contained in MESNEX injection vials can reduce the stability of ifosfamide. Ifosfamide and MESNEX may be mixed in the same bag provided the final concentration of ifosfamide does not exceed 50 mg/mL. Higher concentrations of ifosfamide may not be compatible with MESNEX and may reduce the stability of ifosfamide.

Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration whenever solution and container permit. Any solutions which are discolored, hazy, or contain visible particulate matter should not be used.