Invasive fungal infections have recently been recognized by the WHO as a major health, epidemiological, and economic issue. Their high mortality rates and the emergence of drug resistance have driven the development of new molecules, including olorofim, an antifungal belonging to a new family of compounds, the orotomides. A review was conducted on the PubMed database and the ClinicalTrials.gov website to summarize the microbiological profile of olorofim and its role in the treatment of filamentous fungal infections. Twenty-four articles were included from the search and divided into two groups: an \"in vitro\" group focusing on minimum inhibitory concentration (MIC) results for various fungi and an \"in vivo\" group evaluating the pharmacokinetics (PK), pharmacodynamics (PD), efficacy, and tolerability of olorofim in animal models of fungal infection and in humans. Olorofim demonstrated in vitro and in vivo activity against numerous filamentous fungi, including azole-resistant Aspergillus fumigatus, various dermatophytes, and endemic and dimorphic fungi. in vitro results showed higher MICs for certain Fusarium species and dematiaceous fungi Alternaria alternata and Exophiala dermatitidis; further in vivo studies are needed. Published PK-PD data in humans are limited. The results of the ongoing phase III clinical trial are eagerly awaited to evaluate olorofim\'s clinical impact.

Candidiasis is a common fungal infection caused by Candida species, with Candida albicans being the most prevalent. Resistance to azole drugs, commonly used to treat Candida infections, poses a significant challenge. Transcriptional activator candidate 1 (TAC1) gene has emerged as a key player in regulating drug resistance in C. albicans. This review explores the structure and function of the TAC1 gene and its role in azole resistance. This gene encodes a transcription factor that controls the expression of genes involved in drug resistance, such as efflux pump genes (CDR1, CDR2, and MDR1) and ERG11. Mutations in TAC1 can increase these genes\' expression and confer resistance to azoles. Various TAC1 gene mutations, mostly gain-of-function mutations, have been identified, which upregulate CDR1 and CDR2 expression, resulting in azole resistance. Understanding the mechanisms of azole resistance mediated by the TAC1 gene is crucial for the strategies in the effective antifungal development pipeline.

BACKGROUND: Orbital aspergillosis is a rare sight- and life-threatening fungal infection affecting immunocompromised or otherwise healthy patients. It is often misdiagnosed due to its unspecific clinical and radiologic appearance. Therapeutic delay can have dramatic consequences. However, progress in microbiological diagnostic techniques and therapeutic experience from case series help improve the management of this disease.
METHODS: A 78-year-old immunocompetent woman presented at an eye clinic for subacute swelling, reddening, and ptosis of her left upper eyelid. Based on radiologic and histologic considerations, she was treated for idiopathic orbital inflammation, but her condition worsened. After a second biopsy of the orbital mass, aspergillosis was diagnosed. Her condition improved promptly after initiation of an oral voriconazole treatment. Additionally, using a polymerase chain reaction (PCR) assay, A. fumigatus was identified on tissue of both biopsies and its azole susceptibility was examined simultaneously.
CONCLUSIONS: In the case described here, oral antifungal treatment was sufficient for the therapy of invasive orbital aspergillosis. Performing fungal PCR on orbital tissue can accelerate the diagnostic process and should be performed in ambiguous cases of slowly growing orbital mass. Finally, interdisciplinary management is the key to optimal treatment of orbital tumours and infections.