Isavuconazole for Treatment of Experimental Fungal Endophthalmitis Caused by Aspergillus fumigatus.

Fungal endophthalmitis remains a significant cause of vision impairment and blindness. Moreover, the prognosis is poor, in part due to delay in diagnosis and to limited availability of effective antifungal agents with good ocular penetration. Thus, it is imperative to evaluate the therapeutic efficacy in fungal endophthalmitis of newer antifungal agents. In this study, we assessed the efficacy of isavuconazole in treating Aspergillus fumigatus endophthalmitis in an exogenous mouse model of the disease. Briefly, endophthalmitis was induced by intravitreal (IVT) injection of A. fumigatus spores into immunocompetent C57BL/6 (B6) mouse eyes. Mice were randomized into five groups that received isavuconazole via (i) oral gavage, (ii) IVT injections, (iii) intravenous injection, (iv) IVT injection followed by oral gavage, and (v) IVT injection followed by intravenous injection. Our data showed that isavuconazole treatment via all routes reduced fungal burden in A. fumigatus-infected eyes. This coincided with the preservation of retinal structural integrity (histology analysis) and retinal function (electroretinography [ERG] analysis), resulting in significantly improved disease outcome. Furthermore, isavuconazole treatment reduced the levels of inflammatory cytokines (tumor necrosis factor α [TNF-α], interleukin 1β [IL-1β], and IL-6) and cellular infiltration in the eyes. Notably, oral administration of isavuconazole was as effective in ameliorating endophthalmitis as intravitreal injection of the drug. Collectively, our study demonstrates that isavuconazole is effective in treating A. fumigatus endophthalmitis in mice, indicating its potential use in human ocular infections.