Individualisation of Voriconazole Antifungal Therapy Antifungal Therapy

Inclusion Criteria: * Any adult ≥18 years old * Patients where a new course of voriconazole is indicated for suspected or confirmed invasive aspergillosis or other serious fungal infections that is deemed by the treating physician to be susceptible to voriconazole * Patients must have venous access to permit the administration of voriconazole and enable the procurement of multiple plasma samples to measure voriconazole concentrations. * Estimated creatinine clearance ≥ 50 mL/min * Able to give written informed consent * Considered fit to receive the trial treatment * Able to remain in the hospital for at least 5 days or until they complete their trial treatment * Female patients must satisfy the investigator that they are not pregnant, or are not of childbearing potential, or are using adequate contraception * Men must also use adequate contraception Exclusion Criteria: * Patients with an estimated creatinine clearance \< 50 mL/minute (this precludes the use of intravenous voriconazole) * Patients receiving any form of renal replacement therapy i.e. haemodialysis or haemofiltration * Patients with hepatic insufficiency * Female patients that are pregnant, breast feeding or planning pregnancy during the study * Past history of intolerance to voriconazole * Age \<18 * Evidence of a clinically relevant fungal isolate that is resistant to voriconazole * QT prolongation on ECG * Use of other medications that contraindicate the use of voriconazole * Patients receiving any other medications that are contraindicated with the use of voriconazole i.e. terfenadine, long acting barbiturates, ergot alkaloids, etc. (Refer to SMPC). Only patients on rifampicin, rifabutin, phenytoin, and carbamazepine would have voriconazole precluded. Voriconazole influences with the pharmacokinetics of many additional agents- (see SMPC)- most importantly anti-rejection compounds- cyclosporine, tacrolimus\] * Uncontrolled cardiac, respiratory or other disease or any serious medical or psychiatric disorder that would preclude trial therapy or informed consent. * Hypersensitivity to Voriconazole, its excipients or other triazoles