Hypersensitivity: Caution should be used in prescribing isavuconazole to patients with hypersensitivity to other azole antifungal agents. Hypersensitivity to isavuconazole may result in adverse reactions that include: hypotension, respiratory failure, dyspnoea, drug eruption, pruritus, and rash.
Severe cutaneous adverse reactions: Severe cutaneous adverse reactions, such as Stevens-Johnson syndrome, have been reported during treatment with azole antifungal agents. If a patient develops a severe cutaneous adverse reaction, CRESEMBA should be discontinued.
Cardiovascular: QT shortening: CRESEMBA is contraindicated in patients with familial short QT syndrome (see Contraindications).
In a QT study in healthy human subjects, isavuconazole shortened the QTc interval in a concentration-related manner. For the 200 mg dosing regimen, the least squares mean (LSM) difference from placebo was 13.1 ms at 2 hours post dose [90% CI: 17.1, 9.1 ms]. Increasing the dose to 600 mg resulted in an LSM difference from placebo of 24.6 ms at 2 hours post dose [90% CI: 28.7, 20.4 ms].
Caution is warranted when prescribing CRESEMBA to patients taking other medicinal products known to decrease the QT interval, such as rufinamide.
Elevated liver transaminases or hepatitis: Elevated liver transaminases or hepatitis have been reported in clinical studies (see Adverse Reactions). The elevations in liver transaminases rarely required discontinuation of CRESEMBA. Monitoring of hepatic enzymes should be considered, as clinically indicated.
Hepatitis has been reported with azole antifungal agents including CRESEMBA.
Concomitant use with other medicinal products: CYP3A4/5 inhibitors: Ketoconazole is contraindicated (see Contraindications). For the strong CYP3A4 inhibitor lopinavir/ritonavir, a two-fold increase in isavuconazole exposure was observed. For other strong CYP3A4/5 inhibitors, a less pronounced effect can be expected. No dose adjustment of CRESEMBA is necessary when co-administered with strong CYP3A4/5 inhibitors, however caution is advised as adverse drug reactions may increase (see Interactions).
CYP3A4/5 inducers: Co-administration with mild CYP3A4/5 inducers such as aprepitant, prednisone, and pioglitazone, may result in mild to moderate decreases of isavuconazole plasma levels; co-administration with mild CYP3A4/5 inducers should be avoided unless the potential benefit is considered to outweigh the risk (see Interactions).
CYP3A4/5 substrates including immunosuppressants: Isavuconazole can be considered a moderate inhibitor of CYP3A4/5, and systemic exposure to medicinal products metabolised by CYP3A4 may be increased when co-administered with CRESEMBA. Concomitant use of CRESEMBA with CYP3A4 substrates such as the immunosuppressants tacrolimus, sirolimus or ciclosporin may increase the systemic exposure to these medicinal products. Appropriate therapeutic drug monitoring and dose adjustment may be necessary during co-administration (see Interactions).
CYP2B6 substrates: Isavuconazole is an inducer of CYP2B6. Systemic exposure to medicinal products metabolised by CYP2B6 may be decreased when co-administered with CRESEMBA. Therefore, caution is advised when CYP2B6 substrates, especially medicinal products with a narrow therapeutic index such as cyclophosphamide, are co-administered with CRESEMBA. The use of the CYP2B6 substrate efavirenz with CRESEMBA is contraindicated because efavirenz is a moderate inducer of CYP3A4/5 (see Contraindications).
P-gp substrates: Isavuconazole may increase the exposure of medicinal products that are P-gp substrates. Dose adjustment of medicinal products that are P-gp substrates, especially medicinal products with a narrow therapeutic index such as digoxin, colchicine and dabigatran etexilate, may be needed when concomitantly administered with CRESEMBA (see Interactions).
Limitations of the clinical data: The clinical data for isavuconazole in the treatment of mucormycosis are limited to one prospective non-controlled clinical study in 37 patients with proven or probable mucormycosis who received isavuconazole for primary treatment, or because other antifungal treatments (predominantly amphotericin B) were inappropriate.
For individual Mucorales species, the clinical efficacy data are very limited, often to one or two patients (see Pharmacology: Pharmacodynamics under Actions). Susceptibility data were available in only a small subset of cases. These data indicate that concentrations of isavuconazole required for inhibition in vitro are very variable between genera/species within the order of Mucorales, and generally higher than concentrations required to inhibit Aspergillus species. It should be noted that there was no dose-finding study in mucormycosis, and patients were administered the same dose of isavuconazole as was used for the treatment of invasive aspergillosis.
IV: Infusion-related reactions: During intravenous administration of isavuconazole, infusion-related reactions including hypotension, dyspnoea, dizziness, paraesthesia, nausea, and headache were reported (see Adverse Reactions). The infusion should be stopped if these reactions occur.
Effects on ability to drive and use machines: Isavuconazole has a moderate potential to influence the ability to drive and use machines. Patients should avoid driving or operating machinery if symptoms of confusional state, somnolence, syncope, and/or dizziness are experienced.
Severe hepatic impairment: CRESEMBA has not been studied in patients with severe hepatic impairment (Child-Pugh Class C). Use in these patients is not recommended unless the potential benefit is considered to outweigh the risks. These patients should be carefully monitored for potential drug toxicity. See Dosage & Administration, Adverse Reactions and Pharmacology: Pharmacokinetics under Actions.