The purpose of this study is to compare treatment with olorofim versus treatment with AmBisome® followed by standard of care (SOC) in patients with IFD caused by proven IA or probable lower respiratory tract disease Aspergillus species (invasive aspergillosis, IA).

The mortality rate in immunosuppressed patients with IA is high even with effective modern antifungal drug treatment. Intrinsic and acquired resistance to azoles and amphotericin B, the two most effective classes of treatment, have been identified in Aspergillus species and are linked to this increased mortality.

Currently marketed antifungal drugs have limitations including limited dosage forms, DDIs, and significant adverse reactions.

For patients with IA who do not respond to or cannot tolerate a triazole therapy, treatment options are even more limited.

Olorofim is an antifungal candidate with a novel mechanism of action offering activity against resistant organisms, differences in safety profile, along with oral dosing, predictable and reliable pharmacokinetic (PK) profile and limited potential for DDIs.

The present study is designed to compare the efficacy, safety, and tolerability of olorofim with that of AmBisome® followed by guideline-based hierarchy standard of care (SOC) in patients with IA whose infection is either refractory to or unsuitable for azole therapy.

Inclusion Criteria:

1. Male and female patients ages over 18 years and weighing more than 30 kg
2. Patients with proven IA at any site or probable LRTD IA per EORTC/MSG 2019 criteria as adapted for this study and where the duration of specific therapy for this episode of IA has been ≤ 28 days. For purposes of this inclusion, the duration of specific therapy includes any mould-active therapy given for this episode of IA whether subsequently judged potentially effective or not.
3. Patients requiring therapy with an antifungal agent other than a mould-active azole, and who have had ≤ 96 hours of potentially effective prior therapy. Potentially effective prior therapy includes any agent to which the infecting strain of Aspergillus is likely to be susceptible. There are no exclusions or limitations on such agents (eg, AmBisome® is permitted) other than their duration.
4. AmBisome® is an appropriate therapy for the patient.

Exclusion Criteria:

1. Women who are pregnant or breastfeeding.
2. Known history of allergy, hypersensitivity, or any serious reaction to any component of the study drug
3. Patients with only chronic aspergillosis, aspergilloma, or allergic bronchopulmonary aspergillosis.
4. Suspected mucormycosis (zygomycosis).
5. Patients with a known active second fungal infection of any type, other than candidiasis that can be treated with fluconazole.
6. The requirement for ongoing use of echinocandin as Candida prophylaxis.
7. Microbiological findings (eg, bacteriological, virological) or other potential conditions that are temporally related and suggest a different aetiology for the clinical features.
8. Human immunodeficiency virus (HIV) infection but not currently receiving antiretroviral therapy.
9. Patients with a baseline prolongation of QT using Fridericia's Correction Formula (QTcF) ≥ 500 msec, or at high risk for QT/QTc prolongation.
10. Evidence of hepatic dysfunction.

Adjudicator and sponsor-blinded.