Robert Fullinfaw

Penetration of Voriconazole, 1%, Eyedrops Into Human Aqueous Humor : A Prospective Open-Label Study

OBJECTIVE To determine the therapeutic efficacy of adjuvant use of voriconazole, 1%, eyedrops in the treatment of refractory fungal keratitis. METHODS A prospective open-label trial was conducted to determine voriconazole levels obtained in human aqueous humor after administration of a 1% solution, preserved with 0.01% benzalkonium chloride, every 6 hours for 3 days, or hourly for 4 doses. Ten participants were selected among patients scheduled to undergo elective anterior segment surgery, and samples were tested using validated high-performance liquid chromatography. RESULTS The mean (SD) voriconazole concentrations after hourly dosing (n = 5) was 1.90 (1.12) microg/mL and after a single dosing every 6 hours (n = 5) was 0.94 (1.21) microg/mL, respectively. The mean (SD) sampling times after the last administration of eyedrops were 1.1 (0.5) hours after hourly dosing and 2.1 (0.6) hours after a single dosing every 6 hours. CONCLUSIONS Voriconazole, 1%, eyedrops are well tolerated and penetrate into human aqueous humor when administered at hourly or 6-hourly intervals. They are effective in treating Candida and Aspergillus keratitis, are substantially more affordable than oral therapy, and have less potential to cause systemic adverse effects.

Stability of extemporaneously prepared voriconazole ophthalmic solution

PURPOSE The stability of extemporaneously prepared voriconazole ophthalmic solution was studied. METHODS Voriconazole solutions (2% and 1%) were reconstituted from the i.v. formulation. After thorough mixing, 3-mL samples of each of the resulting 2% and 1% solutions were filtered into eyedroppers. Three samples for both solutions were analyzed in triplicate at each time point. The 2% voriconazole ophthalmic solutions were stored at 2-8 degrees C, 25 degrees C, and 40 degrees C. The 1% voriconazole eye drops were stored at 2-8 degrees C. The 2% voriconazole solution samples were analyzed at time 0 and at weeks 1, 2, 4, 8, 16, and 32. The 1% solution samples were analyzed at time 0 and at weeks 6 and 14. Stability was measured using high-performance liquid chromatographic analysis. RESULTS The 2% voriconazole ophthalmic solution demonstrated excellent stability at 2-8 degrees C and 25 degrees C for up to 16 weeks. The voriconazole solution displayed no significant change in pH at all time intervals. No change in visual appearance or clarity was observed in the 2% voriconazole eye drops at any point of the study for all study temperatures. Voriconazole 1% solution was stable at 2-8 degrees C for up to 14 weeks. CONCLUSION Voriconazole 2% (20 mg/mL) solution preserved with 0.01% benzalkonium chloride prepared as alternative antifungal eye drops was stable for 16 weeks when stored at 2-8 degrees C and 25 degrees C and for 8 weeks when stored at 40 degrees C, while voriconazole 1% solution was stable at 2-8 degrees C for up to 14 weeks.

Penetration of 1% voriconazole eye drops into human vitreous humour: a prospective, open‐label study

Purpose:  Although there have been reports describing the use of 1% voriconazole eye drops in the treatment of fungal infections, little is known about the penetration of voriconazole eye drops into the vitreous humour. The aim of this study was to elucidate if topical application of 1% voriconazole eye drops could reach therapeutic levels in the vitreous humour.

Rapid and Sensitive Liquid Chromatography/Mass Spectrometry Assay for Caspofungin in Human Aqueous Humor

ABSTRACT A rapid, precise, and sensitive liquid chromatography/mass spectrometry (LC/MS) method to quantify the caspofungin concentration in human aqueous humor was developed and validated. Sample preparation involved simple dilution of aqueous humor samples with acetonitrile. Azithromycin was the internal standard. Good linearity over 10 to 5,000 ng/ml was observed. The lower limit of quantification was 10 ng/ml. The intra- and interday accuracies (percent bias) were within 11%, while the intra- and interday precisions were within 6%.

Prospective Open-Label Study of the Administration of Two-Percent Voriconazole Eye Drops

ABSTRACT Thirteen human subjects scheduled for elective anterior segment eye surgery received hourly 2% voriconazole eye drops 4 hours presurgery. No side effects were reported. Significantly, the voriconazole concentration in the aqueous humor of the eye was similar to that reported for the 1% voriconazole solution, suggestive of concentration-independent absorption.

Penetration of Topically Administered 0.5-Percent Caspofungin Eye Drops into Human Aqueous Humor

ABSTRACT Ten participants attending elective anterior segment eye surgery received 0.5% caspofungin eye drops either 1 drop hourly for 4 h or 1 drop an hour before surgery. The eye drops were generally well tolerated. In the absence of inflammation or corneal abrasion, topical caspofungin does not achieve clinically relevant concentrations.

Chemical Stability of Voriconazole 1% Eye Drops

Case reports suggest that voriconazole 1% eye drops are effective in treating refractory fungal keratitis. There are no data available on the stability and shelf‐life of extemporaneously prepared voriconazole 1% eye drops.

A mouse model of hereditary coproporphyria identified in an ENU mutagenesis screen

ABSTRACT A genome-wide ethyl-N-nitrosourea (ENU) mutagenesis screen in mice was performed to identify novel regulators of erythropoiesis. Here, we describe a mouse line, RBC16, which harbours a dominantly inherited mutation in the Cpox gene, responsible for production of the haem biosynthesis enzyme, coproporphyrinogen III oxidase (CPOX). A premature stop codon in place of a tryptophan at amino acid 373 results in reduced mRNA expression and diminished protein levels, yielding a microcytic red blood cell phenotype in heterozygous mice. Urinary and faecal porphyrins in female RBC16 heterozygotes were significantly elevated compared with that of wild-type littermates, particularly coproporphyrinogen III, whereas males were biochemically normal. Attempts to induce acute porphyric crises were made using fasting and phenobarbital treatment on females. While fasting had no biochemical effect on RBC16 mice, phenobarbital caused significant elevation of faecal coproporphyrinogen III in heterozygous mice. This is the first known investigation of a mutagenesis mouse model with genetic and biochemical parallels to hereditary coproporphyria. Summary: A mouse mutagenesis model of hereditary coproporphyria has significant genetic and biochemical parallels to that of the human condition.

Open-Label Study of Absorption and Clearance of 1% Voriconazole Eye Drops

ABSTRACT Twenty participants undergoing elective cataract surgery received 1% voriconazole eye drops (1 drop per eye) either 20, 40, 60, or 80 min before surgery. Median voriconazole concentrations of 1.9 to 3.2 mg/liter in aqueous humor samples were attained over the first 80 min, which were higher than in vitro MIC90 values for typical fungi that cause keratitis.