Busulfex

/ Tzamal

BUSULFEX should be administered intravenously via a central venous catheter as a two-hour infusion every 6 hours x 4 consecutive days for a total of 16 doses. All patients should be premedicated with appropriate anti-convulsant therapy (e.g. phenytoin, benzodiazepines) to prevent seizures, as busulfan is known to cross the blood brain barrier. Antiemetics of the 5-HT3 class should be administered prior to the first dose of BUSULFEX and continued on a fixed schedule through administration of BUSULFEX or considered through completion of the preparative regimen.
The usual adult dose of BUSULFEX in combination with cyclophosphamide as a
preparative regimen prior to bone marrow or peripheral blood progenitor cell replacement support is 0.8 mg/kg of ideal body weight or actual body weight,
whichever is lower. For obese, or severely obese patients, dosing based on adjusted ideal body weight could be considered. Ideal body weight (IBW) should be calculated as follows: (height in cm, and weight in kg): IBW (kg; men) = 50 + 0.91 × (height -152); IBW (kg; women) = 45 + 0.91 × (height – 152). Adjusted ideal body weight (AIBW) should be calculated as follows: AIBW = IBW + 0.25 × (actual weight – IBW).
Cyclophosphamide in combination with BUSULFEX was given on each of two days  as a one-hour infusion at 60 mg/kg beginning on BMT day -3, six hours following the 16th dose of BUSULFEX.

BUSULFEX (busulfan) Injection is indicated for use in combination with other chemotherapeutic agents and/or radiotherapy as a conditioning regimen prior to hematopoietic progenitor cell transplantation.

BUSULFEX (busulfan) Injection is contraindicated in patients who are sensitive,
allergic or intolerant of the drug or its vehicle.

There are no known or manifest interactions with the antifungal agent fluconazole, however, itraconazole decreases busulfan clearance by up to 25%, and may produce an AUC > 1500 µMol/min in some patients. Metronidazole significantly increases plasma levels of busulfan, which may lead to treatment-related toxicities.
It has been reported that phenytoin increases the clearance of busulfan by 10% or more, possibly due to the induction of GST. Since virtually all patients are empirically treated with anticonvulsants (phenytoin, clonazepam), the dose of BUSULFEX should be adjusted to account for enhanced clearance.
Busulfan is eliminated from the body via conjugation with glutathione. Since
acetaminophen may decrease glutathione levels in blood and tissues, concurrent or prior use (<72 hours) may result in modified busulfan clearance.