Criteria & Principles
ID consult REQUIRED.
Usual Dose & Administration
372 mg PO/IV q8h x 6 doses THEN
372 mg PO/IV q24h
ECMO
Consider higher loading doses (i.e. 744 mg x1 then, then 372 mg q8h x5 doses) in patients on ECMO with active infection alongside therapeutic drug monitoring.
Adjustment of Dose & Administration
Renal Adjustment
No dose adjustment is required, including those with ESRD.
Hepatic Adjustment
No dose adjustment is necessary in patients with mild or moderate hepatic impairment. Isavuconazole has not been studied in patients with severe hepatic impairment.
Serum Concentration Monitoring
Consult Transplant ID
Drug-Specific Information
372 mg isavuconazonium sulfate (prodrug) = 200 mg isavuconazole
Oral capsules and intravenous infusion formulations are bioequivalent. Dosage adjustment is not required when switching between formulations.
In an electrophysiology study, isavuconazonium was found to shorten the QTc interval in a dose-/concentration-related manner.
ISAVUCONAZOLE is both a substrate and moderate inhibitor of CYP3A4, a substrate of CYP3A5 and UGT, and a mild inhibitor of P-gp.
| Drug | Recommendation | |
| Contraindicated |
Lopinavir/ritonavir Rifampin Phenytoin/fosphenytoin Carbamazepine St. John's Wort Phenobarbital |
Do not use |
| Warning/Precaution | Tacrolimus | Increase in tacrolimus exposure. Monitor FK-506 drug concentrations. Use with caution. |
| Mycophenolate mofetil | Increase MMF exposure. Use with caution. | |
| Sirolimus | Increase in sirolimus exposure. Monitor sirolimus concentrations. Use with caution | |
| Bupropion | Decrease bupropion exposure. Use with caution |
According to the manufacturer, there is no delayed release or extended release technology in Isavuconazole capsules. In special circumstances, based on clinical need, the capsules can be opened, mixed with sterile water, and given via tube.
Cost Index
$$$$$$ (51+)
General Notes
- Up-to-date cost information, click here
- IV antimicrobials outpatient (OPAT) dosing, click here
- Obesity dosing weight recommendations here
- Helpful drug-drug interaction check website here
- When dosing guidance is provided it is important to note the following:
Fixed (ie non weight-based) doses in adults are historically based on a 70 kg patient. Specific disease states or individual patients may warrant dosages that differ from the above recommendations. Since product-specific criteria for dose adjustment based on creatinine clearance exist, consult product information regarding specific recommendations for dosage adjustment based on estimated creatinine clearance.