[Level of evidence for therapeutic drug monitoring of voriconazole]

Toxicity of simultaneous intrastromal and intracameral injection of voriconazole on corneal endothelium in a rabbit model

PURPOSE

To investigate the toxicity of repeated simultaneous intrastromal and intracameral injections of voriconazole in corneal endothelial cells in a rabbit model.

METHODS

Thirty-six eyes of 18 New Zealand white rabbits (six eyes per group) were divided into 6 groups according to the concentration of voriconazole (Group A, 0%; Group B, 0.05%; Group C, 0.1%; Group D, 0.25%; Group E, 0.5%; Group F, 1%). A combination of intrastromal and intracameral voriconazole injections were administrated to the eyes of each group three times on days 0, 3, and 7. Corneal clouding grades and central corneal thickness (CCT) were examined on days 0, 3, 7, 10, and 14. The endothelial cell counts (ECC) were measured on days 0 and 14. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were performed on day 14.

RESULTS

Group F (1%) showed more severe corneal clouding than the other groups (Groups A-E) from day 7 (p < 0.05, respectively). There were no significant differences in CCT and ECC among the six groups at any time point (p > 0.05, respectively). SEM revealed blurring of the cell border and loss of microvilli at concentrations ≥0.25% (Groups D-F). TEM revealed microstructural changes in endothelial cells at concentrations ≥0.1% (Groups C-F), and multiple vacuoles were observed at a concentration of 1% voriconazole (Group F).

CONCLUSIONS

Repeated simultaneous intrastromal and intracameral voriconazole injections at a concentration of 0.1% or higher induced microstructural endothelial damage in rabbit corneal endothelial cells.

The impact of gene polymorphism and hepatic insufficiency on voriconazole dose adjustment in invasive fungal infection individuals

Voriconazole (VRZ) is a broad-spectrum antifungal medication widely used to treat invasive fungal infections (IFI). The administration dosage and blood concentration of VRZ are influenced by various factors, posing challenges for standardization and individualization of dose adjustments. On the one hand, VRZ is primarily metabolized by the liver, predominantly mediated by the cytochrome P450 (CYP) 2C19 enzyme. The genetic polymorphism of CYP2C19 significantly impacts the blood concentration of VRZ, particularly the trough concentration (Ctrough), thereby influencing the drug's efficacy and potentially causing adverse drug reactions (ADRs). Recent research has demonstrated that pharmacogenomics-based VRZ dose adjustments offer more accurate and individualized treatment strategies for individuals with hepatic insufficiency, with the possibility to enhance therapeutic outcomes and reduce ADRs. On the other hand, the security, pharmacokinetics, and dosing of VRZ in individuals with hepatic insufficiency remain unclear, making it challenging to attain optimal Ctrough in individuals with both hepatic insufficiency and IFI, resulting in suboptimal drug efficacy and severe ADRs. Therefore, when using VRZ to treat IFI, drug dosage adjustment based on individuals' genotypes and hepatic function is necessary. This review summarizes the research progress on the impact of genetic polymorphisms and hepatic insufficiency on VRZ dosage in IFI individuals, compares current international guidelines, elucidates the current application status of VRZ in individuals with hepatic insufficiency, and discusses the influence of CYP2C19, CYP3A4, CYP2C9, and ABCB1 genetic polymorphisms on VRZ dose adjustments and Ctrough at the pharmacogenomic level. Additionally, a comprehensive summary and analysis of existing studies' recommendations on VRZ dose adjustments based on CYP2C19 genetic polymorphisms and hepatic insufficiency are provided, offering a more comprehensive reference for dose selection and adjustments of VRZ in this patient population.

Amphotericin B May Decrease the Serum Level of Voriconazole: A Case Report and Brief Review of Literature

Background

Combination therapy with amphotericin B (AmB) and Voriconazole are sometimes used due to reducing AmB-related adverse reactions and improving outcomes. However, there was no report whether AmB would affect the serum level of Voriconazole.

Case Presentation

A patient was in presumption of invasive fungal infection. Voriconazole and amphotericin B was combined for administration. The results showed that serum levels of Voriconazole were dramatically reduced when combined AmB, whereas went up when receiving Voriconazole alone.

Conclusion

AmB might decrease the level of Voriconazole. Such a combination of AmB and Voriconazole cannot be considered appropriate until more data are available.

Voriconazole-Induced Cholestatic Hepatotoxicity in an Immune Competent Patient

Voriconazole is a frequently prescribed anti-fungal medication used in particular for invasive aspergillosis. Voriconazole-induced hepatotoxicity is a relatively rare but serious clinicopathologic entity. We report a patient presenting with impaired liver function test results pointing towards the cholestatic picture. The patient had initial blood tests to confirm cholestasis, followed by imaging modalities that did not show any obstruction along the common bile duct and/or pancreatic pathway. The patient’s voriconazole dose reduction was advised, resulting in lower levels of abnormal liver function tests.

Novel investigational therapies for onychomycosis: an update

INTRODUCTION

Onychomycosis is an infection of the nail plate that is prevalent among the ageing population. Onychomycosis is difficult to treat with low initial cure rates, high rates of relapse, and reinfection. Present treatment options include oral and topical therapies, with oral therapies yielding better results. However, there has been a greater emphasis on the development of topical antifungal therapies as they have fewer side effects and drug interactions.

AREAS COVERED

This review summarizes new and reformulated drugs. Results from in vitro studies to Phase III clinical trials are discussed. Novel drugs include: the oral azole VT-1161, the topical azole efinaconazole, the benzoxaborole tavaborole, reformulations of terbinafine P-3058 and LI-P, novel inhibitor of succinate dehydrogenase ME1111, and off-label use of tazarotene. Enhanced permeation of the morpholine amorolfine through the nail plate is also discussed using ultraviolet (UV) curable gels, and a fractional CO2 laser.

EXPERT OPINION

Novel topical antifungals and the reformulation of current antifungals have demonstrated marked improvement in nail penetration. Current research has an emphasis on topical therapies due to their minimized risk for adverse effects and higher patient demand. Nevertheless, few topical agents have surfaced in the past few years and the investigation of efficacious combination therapies may become more important.

Saprochaete clavata invasive infection in a patient with severe aplastic anemia: Efficacy of voriconazole and liposomal amphotericin B with adjuvant granulocyte transfusions before neutrophil recovery following allogeneic bone marrow transplantation

We report a case of a 27-year old man with severe aplastic anemia who developed a Saprochaete clavata (Geotrichum clavatum) disseminated invasive infection shortly prior a scheduled allogeneic bone marrow transplantation. Treatment with a combination of voriconazole, liposomal amphotericin B and adjuvant granulocyte transfusions was successful before neutrophil recovery.

Trichosporon faecale invasive infection in a patient with severe aplastic anemia: Efficacy of voriconazole and liposomal amphotericin B before neutrophil recovery

We report a case of a 51-year old man with a severe aplastic anemia who developed an invasive trichosporonosis to Trichosporon faecale with fungemia and skin lesions during severe neutropenia. The treatment was successful before neutrophil recovery with a combination of voriconazole and liposomal amphotericin B.

Therapeutic drug monitoring in the treatment of invasive aspergillosis with voriconazole in cancer patients--an evidence-based approach

Invasive aspergillosis (IA) is a life-threatening complication in hematological cancer patients. Voriconazole (VCZ) is the established first-line treatment of IA. VCZ has a nonlinear pharmacokinetic profile and exhibits considerable variability of drug exposure. Therefore, therapeutic drug monitoring (TDM) of VCZ may help to improve treatment results in IA patients, but evidence-based data on the clinical use of TDM in patients treated with VCZ for IA are scarce. Evidence-based guidance is needed to support decisions on the use of TDM in routine VCZ therapy of IA. Our present analysis assessed published studies for evidence-based criteria for TDM of VCZ to improve efficacy and safety of IA therapy in cancer patients. Literature searches of MEDLINE and Cochrane database were performed. We identified 27 clinical studies reporting on the use of plasma level monitoring and/or TDM for VCZ. For each study, strength of recommendation and quality of evidence were categorized according to predefined criteria. A number of studies were published on plasma level monitoring (PLM) and TDM in VCZ therapy of IA. Across studies, VCZ levels >5-5.5 mg/L were found to be associated with toxicity, while reaching minimum levels of >1-2 mg/L appeared to improve efficacy. Timing, frequency, and intervention thresholds and dosage increments of VCZ for adjustment of plasma levels remain to be established. Currently, there is still no conclusive evidence for recommendations in routine clinical practice. More data from prospective randomized studies with TDM are desirable to provide a solid evidence basis for these approaches.