Isavuconazonium Sulfate Capsules (Cresemba) is a triazole antifungal drug. As a new-generation broad-spectrum antifungal agent, it exerts its antifungal effect by inhibiting the biosynthesis of ergosterol in fungal cell membranes.

Precautions for Administration of Isavuconazonium Sulfate Capsules (Cresemba)

Special Instructions for Administration

Capsules can be taken with food or on an empty stomach.

Capsules should be swallowed whole; do not chew, crush, dissolve, or open them.

Intravenous formulations must be administered via an infusion set equipped with an in-line filter (with a pore size of 0.2 to 1.2 micrometers).

The intravenous infusion time should be at least 1 hour; intravenous bolus injection is not allowed.

Contraindications

Patients with a hypersensitivity to isavuconazole.

Concomitant use with strong CYP3A4 inhibitors (such as ketoconazole or high-dose ritonavir).

Concomitant use with strong CYP3A4 inducers (such as rifampicin, carbamazepine, St. John's wort, or long-acting barbiturates).

Patients with familial short QT syndrome.

Monitoring During Administration of Isavuconazonium Sulfate Capsules (Cresemba)

Monitoring of Treatment Response

During treatment, the patient's clinical manifestations, imaging changes, and microbiological test results should be evaluated regularly.

For invasive fungal infections, the treatment response is usually slow, and a sufficient course of treatment (generally at least 6-12 weeks) is required to assess the therapeutic effect.

Laboratory Monitoring

Liver function monitoring: Liver function indicators such as alanine transaminase (ALT), aspartate transaminase (AST), alkaline phosphatase, and total bilirubin should be monitored regularly before and during treatment.

If abnormal liver function occurs, close monitoring is required to check whether it progresses to more severe liver injury. Cresemba should be discontinued if clinical symptoms and signs of liver disease related to Cresemba appear.

Electrolyte monitoring: Special attention should be paid to serum potassium levels, as hypokalemia is a common adverse reaction of this drug (with an incidence rate of approximately 14%).

Blood drug concentration monitoring: Although routine monitoring of isavuconazole blood concentration is not mandatory for regular treatment, trough concentration measurement may be considered in special cases (such as suspected poor absorption, drug interactions, or treatment failure).

Monitoring of Drug Interactions

Immunosuppressants: When used concomitantly with cyclosporine, sirolimus, or tacrolimus, the blood concentrations of these drugs may increase. Therefore, their concentrations should be monitored and their doses adjusted accordingly.

P-gp substrate drugs: For P-gp substrate drugs with a narrow therapeutic window (such as digoxin), dose adjustment may be required when they are used concomitantly with Cresemba.

CYP3A4 substrate drugs: The exposure of sensitive CYP3A4 substrates (such as midazolam) may increase by approximately 2-fold when used concomitantly with Cresemba. It is necessary to consider reducing the doses of these drugs.