A Validated Ultra-Performance Liquid Chromatographic Method for the Simultaneous Determination of Nadifloxacin, Mometasone Furoate and Miconazole Nitrate in Their Combined Dosage Form and Spiked Human Plasma Samples.

Nadifloxacin, mometasone furoate and miconazole nitrate are formulated together as a topical antifungal dosage form. In this work, a reversed-phase ultra-performance liquid chromatographic method coupled with a diode array detector (RP-UPLC-DAD) was developed and validated to determine nadifloxacin, mometasone furoate and miconazole nitrate simultaneously in their bulk powder, in pharmaceutical preparation and in spiked human plasma samples. Separation was achieved on an ACQUITY UPLC C18 column of 2.2 µm particle size (2.1 × 100 mm) via isocratic elution using a mobile phase consisting of methanol, acetonitrile and water with ratio (50:20:30; v/v/v) and 0.1 g ammonium acetate, then pH was adjusted to (7.00) using acetic acid, flow rate 0.6 mL/min, temperature 30°C and UV detection at 220 nm. The method is linear in a range from 5 to 400 µg/mL for both nadifloxacin and miconazole nitrate and from 20 to 500 µg/mL for mometasone furoate. The method was validated according to the ICH guidelines then applied successfully to determine the mentioned drugs in their pharmaceutical preparation and spiked human plasma samples. For plasma samples, the results showed that the method can determine nadifloxacin, mometasone furoate and miconazole nitrate in human plasma samples with high accuracy and precision.

Enantioselective separation and determination of miconazole in rat plasma by chiral LC-MS/MS: application in a stereoselective pharmacokinetic study.

Miconazole has one chiral center, and consists of two enantiomers. In this study, a novel chiral liquid chromatography-tandem mass spectrometry method was developed for enantioselective separation and determination of miconazole in rat plasma. For the first time, the enantioselective pharmacokinetics of miconazole was investigated by the current method. Firstly, attempts were made to separate the enantiomers in reversed-phase mode with a mobile phase that was mass spectrometry compatible. Baseline separation was achieved on a Chiralpak IC column with a mobile phase composed of acetonitrile and aqueous ammonium hydrogen carbonate (5 mM; 80:20, v/v). Data were acquired in multiple reaction monitoring mode with positive electrospray ionization by triple-quadrupole mass spectrometry. Then, overall method validation regarding the linearity, accuracy, precision, extraction recovery, matrix effect, and stability of each enantiomer was performed, and acceptable results were obtained for all of these. Finally, the method developed was applied in an enantioselective pharmacokinetic study of miconazole enantiomers in rats after oral administration of racemic miconazole at doses of 5 and 10 mg/kg. The results demonstrated that (-)-(R)-miconazole had a higher concentration than (+)-(S)-miconazole in plasma, with a ratio of 1.3-1.7 for both doses. This is the first experimental evidence of enantioselective behavior of miconazole in vivo, and provides a reference for clinical practice and encourages further research into miconazole enantioselective metabolism and drug interactions. Graphical Abstract A stereoselective pharmacokinetic study of the miconazole enantiomers was investigated using a novel chiral liquid chromatography-tandem mass spectrometry method. Baseline separation was achieved on Chiralpak IC column, and Chiralcel OJ column was used to collect single enantiomer. A significant difference between the two enantiomers was observed in view of the plasma concentration.

Systemic uptake of miconazole during vaginal suppository use and effect on CYP1A2 and CYP3A4 associated enzyme activities in women.

PURPOSE: To investigate if the ordinary use of a vaginal suppository containing miconazole results in systemic absorption that is sufficient to affect the activities of CYP1A2 and CYP3A4, which are major drug- and steroid-metabolising enzymes. METHODS: In 20 healthy non-pregnant women aged 18-45 years, the serum concentration of miconazole was determined following the use of a vaginal suppository containing 1,200 mg miconazole. Enzyme activities of CYP1A2 and CYP3A4 were determined as metabolic ratios of caffeine (CMR = (AFMU + 1MU + 1MX)/17DMU) and quinidine (QMR = 3-hydroxy-quinidine/quinidine) respectively before and 34 h after insertion of the suppository. Miconazole was analysed by LC-MS/MS, while caffeine and metabolites were analysed by HPLC-UV and quinidine and hydroxy-quinidine were analysed by HPLC fluorescence. RESULTS: All 20 women had measurable concentrations of miconazole in serum (mean ± SD: 12.9 ± 5.6 µg/L; range: 3.5-24.6 µg/L). Although not statistically significant, an association between the serum concentrations of miconazole and the inhibition of CYP1A2 activity was indicated. No relation was observed between the CYP3A4 activity and the miconazole serum concentration. CONCLUSIONS: Miconazole is absorbed via the vaginal mucosa to the systemic circulation in measurable concentrations. Our data indicate a concentration-dependent inhibition of CYP1A2, but the effect is negligible compared with the variation in the activity of CYP1A2 and is regarded to be of no clinical significance to the women. However, further studies on the ability of miconazole to be transferred across the placenta or to interfere with the placental function are warranted to secure safe use during pregnancy.

Randomized, comparative, double-blind, double-dummy, multicenter trial of miconazole buccal tablet and clotrimazole troches for the treatment of oropharyngeal candidiasis: study of miconazole Lauriad® efficacy and safety (SMiLES).

BACKGROUND: Oropharyngeal candidiasis (OPC) is the most common opportunistic infection among persons infected with human immunodeficiency virus (HIV). Once-daily miconazole 50 mg buccal tablet (MBT) is a novel delivery system using an extended-spectrum azole with potent in vitro activity against many Candida species, including some that may be resistant to other azoles. METHODS: This phase 3, double-blind, double-dummy, multicenter trial evaluated 578 randomized patients with HIV infection and OPC. The study compared the efficacy and safety of MBT once daily with clotrimazole 10 mg troches (CT) 5 times daily for 14 days. The co-primary efficacy endpoints were clinical cure at test of cure (TOC) visit (days 17-22) in the intent-to-treat (ITT) and per protocol (PP) populations. RESULTS: Clinical cure rate at TOC visit for MBT-treated patients was statistically noninferior to CT-treated patients in both the ITT (61% vs 65%) and PP (68% vs 74%) populations. Secondary endpoints, safety, and tolerability were similar between treatment groups. CONCLUSIONS: In this large trial, once-daily MBT was shown to be noninferior to CT 5 times daily in the treatment of OPC in HIV-positive patients. MBT offers an effective, safe, and well-tolerated topical treatment option for OPC administered as a convenient once-daily dose.

Oral voriconazole and miconazole oral gel produce comparable effects on the pharmacokinetics and pharmacodynamics of etoricoxib.

PURPOSE: The effect of topical miconazole oral gel and systemic oral voriconazole on the pharmacokinetics of oral etoricoxib was studied in 12 healthy volunteers. METHODS: Plasma concentrations of etoricoxib, miconazole, voriconazole, and thromboxane B(2) generation were followed after ingestion of 60 mg etoricoxib without pretreatment, after topical administration of miconazole oral gel (85 mg x 3, 3 days), or after oral voriconazole (400 mg x 2, 1st day, 200 mg x 2, 2nd day). RESULTS: Etoricoxib area under the plasma concentration-time curve (AUC(0-00)) and maximum plasma concentration (C(max)) geometric mean ratios (GMR) with/without miconazole were 1.69 {90% confidence interval (CI); 1.46-1.92} and 1.12 (90% CI; 0.99-1.25), respectively, and corresponding GMRs with/without voriconazole were 1.49 (90% CI; 1.37-1.61) and 1.19 (90% CI; 1.08-1.31), respectively. CONCLUSIONS: Miconazole oral gel and oral voriconazole produced comparable increase in the exposure to etoricoxib, presumably via CYP3A inhibition.

Pharmacokinetics of the antimicrobial agents rifampicin and miconazole released from a loaded central venous catheter.

The time course of rifampicin and miconazole concentrations after insertion of a polyurethane catheter loaded with these antibiotics were studied. Data from controlled release experiments in vitro were used, and the concentration time courses of the antimicrobials in serum were calculated by pharmacokinetic simulations. Systemic therapy using typical dosages (rifampicin 600 mg/day iv, miconazole 3 x 200 mg/day iv) results in rifampicin concentrations between 54 and 8424 microg/L, and miconazole concentrations between 3567 and 4676 microg/L. After insertion of a polyurethane catheter loaded with these antibiotics, the maximal concentrations after catheter placement were determined as 6 microg/L at 10.7h for rifampicin, and 13 microg/L at 28.6 h for miconazole. Assuming that the total amount of antibiotics incorporated in the catheter matrix were bioavailable ('worst case'), the resulting maximal concentrations calculated by simulation are 10 microg/L for rifampicin and 65 microg/L for miconazole. Maximal concentrations of rifampicin or miconazole resulting from the insertion of a polyurethane catheter loaded with these antibiotics are, therefore, far below the concentrations resulting from a systemic therapy with the same antimicrobial agents. Even in the worst case, the danger of selecting resistant bacterial strains seems remote because the systemic drug levels are magnitudes of order below subinhibitory concentrations.

Bioavailability study of a 1200 mg miconazole nitrate vaginal ovule in healthy female adults.

This study was undertaken to determine the bioavailabilityof a 1200 mg miconazole nitrate vaginal ovule in 20 healthy premenopausal females following a single application (Day 1, Group 1) and two applications, 48 hours apart (Day 1 and Day 3, Group 2). In Dose Group 1 (n = 10), the mean Cmax of 10.7 ng/ml occurred at 18.4 hours. The average plasma miconazole concentration was calculated to be 5.7 ng/ml during the 4- to 96-hour time interval. In Dose Group 2 (n = 10), mean Cmax values were 10.8 ng/ml and 12.0 ng/ml and occurred at 18.4 hours (Day 1) and 16.0 hours (Day 3), respectively. Comparing AUC0-48 on Days 1 and 3 (338 vs. 408 ng x h/ml) indicated small accumulation of plasma miconazole, while AUC0-48 obtained from Dose Group 2, Day 1 was similar to that of Dose Group 1 (338 vs. 329 ng x h/ml, respectively). Plasma miconazole profiles were best described by a monoexponential equation with zero-order input. Pharmacokinetic simulations performed on the pooled data from two dose groups (n = 20) suggest a steady-state accumulation after five doses administered daily or three doses taken once every other day. Drug exposure was similar to that of the marketed formulation (MONISTAT 7 vaginal cream), applied once daily for 7 days and more than 100-fold less than that reported when given intravenously or orally.

Strategy for the development of automated methods involving dialysis and trace enrichment as on-line sample preparation for the determination of basic drugs in plasma by liquid chromatography.

Among the sample preparation techniques, dialysis followed by clean-up and enrichment of the dialysate on a pre-column has proved to be a useful approach for the LC determination of drugs in plasma. By use of sample processors, like the ASTED system, such bioanalytical methods can be fully automated, the dialysis and trace enrichment steps being directly coupled to LC. In order to facilitate the development of such automated methods, a strategy based on a decision tree has been elaborated. After the selection of appropriate conditions for the LC analysis, the decision tree provides information about suggested starting conditions and guidelines for the optimisation of the most important parameters likely to influence analyte recovery and method selectivity. The plasma samples are dialysed on a cellulose acetate membrane in the static-pulsed mode and the dialysate is enriched on a trace enrichment pre-column packed with octadecyl silica or with a strong cation-exchange material. This decision tree is until now restricted to the analysis of basic drugs in plasma. In order to demonstrate the applicability of this method development strategy, an automated procedure based on the coupling of dialysis with trace enrichment has been developed for the LC determination of antifungal agents (clotrimazole, econazole and miconazole) in plasma.

Evaluation of miconazole activity contained in human serum to hypha of Aspergillus fumigatus.

Aspergillus fumigatus is an opportunistic pathogen, especially in an immunocompromised host. This fungus grows in a hyphal form in infected tissues; therefore, new tests to examine hyphal susceptibility are needed. In this study, we measured the mycotic activity of miconazole (MCZ) contained in human serum against A. fumigatus using the BioCell-Tracer method. Three serum samples were obtained from the same patient who was injected with 600 mg b.i.d. MCZ daily for 2 days. The concentrations of MCZ in the serum sample were 8.8, 3.5, and 1.6 micro g/ml, respectively. The serum containing 8.8 micro g/ml of MCZ inhibited hyphal growth 90 minutes after administration, and the hypha stopped growing. The serum containing 3.5 micro g/ml MCZ stopped hypha growth 100 minutes after administration, but re-growth of the hypha was observed at this concentration of MCZ. Serum containing 1.6 micro g/ml did not inhibite hyphal growth, nor did control serum have any inhibitory activity foward hyphae. Based on these results, we conclude that the BioCell-Tracer is a useful method for determining the effects on filamentous fungi of antifungal agents in the serum.

Microbiological and HPLC analysis of miconazole in skin, serum and phase-solubility studies.

OBJECTIVE: To develop stability-indicating assays for miconazole. METHODS: A reversed phase high-performance liquid chromatographic assay and a bioassay were developed. RESULTS: The HPLC and the bioassay were linear in the range of 0.5-100 and 0.64-1.56 microg/ml, respectively. The sensitivity of HPLC and bioassay were 0.5 and 0. 64 microg/ml, respectively. The bioassay was less cumbersome and much faster than the HPLC assay by obviating the need for extraction from serum. Miconazole content in the phase-solubility studies and in the serum samples was comparatively evaluated by both assay methods. There was good correlation between the two methods (r2 > 0. 99). The drug extraction efficiency from the serum and the skin were 97.7 and 90.2%, respectively. Where necessary, the bioassay can be an alternative choice for the HPLC analysis. The within and between day variations of the HPLC assay were 3.6 and 4.9%, respectively.

Pharmacokinetics of miconazole in serum and exudate of pelvic retroperitoneal space after radical hysterectomy and pelvic lymphadenectomy.

Due to the increased number of compromised hosts with fungal infections, doctors have recently started prescribing antifungal agents. In the field of gynecology, however, the choice of which drug to use has been difficult. The efficacies of these drugs depend on their antifungal spectra, potencies and concentrations in tissues. The present study was designed to investigate the pharmacokinetics of miconazole in the exudate of the retroperitoneal space that is formed after radical hysterectomy and pelvic lymphadenectomy. A total of 600 mg of miconazole was administered to the patients for exactly 60 min using an automatic drip-infusion pump. The parameters of the formulas analyzed by the two-compartment model were determined using the least-squares method, and a simulation curve was made. The maximum drug concentration (Cmax) of miconazole in serum was 6.26 mg/l 1 h after drip infusion commencement and the t1/2 in serum was 8.86 h. The value of the area under the time-serum concentration curve (AUC) in serum was 19.13 mg/h per l. The Cmax of miconazole in the exudate of the retroperitoneal space was 0.13 mg/l 2.48 h after the drip infusion was started. The value of AUC in the exudate was 2.52 mg/h per l.

High-performance liquid chromatographic analysis for the determination of miconazole in human plasma using solid-phase extraction.

A high-performance liquid chromatographic method for the determination of miconazole in human plasma is described. A solid-phase extraction was performed on an octadecyl (C18) cartridge. Miconazole was eluted with methanol, separated on a reversed-phase column and was measured by ultraviolet detection at 230 nm. The absolute extraction recovery from plasma samples was 85%. The limit of detection was established as 5 ng/ml. The coefficient of variation of the determination of plasma levels by this method over the standard curve concentration range was less than 10%, except with the concentration of 10 ng/ml. The plasma levels of miconazole in twelve healthy volunteers given a 250-mg oral dose of two tablet forms were determined by this method.

Rapid high performance liquid chromatographic assay for antifungal agents in human sera.

Serum concentration of seven antifungal agents, amphotericin B, 5-flucytosine, ketoconazole, fluconazole, itraconazole, miconazole and econazole were assayed using a single step sample preparation and an isocratic High Performance Liquid Chromatography (HPLC) procedure based on three mobile phases of similar components. Our method was simple, flexible and rapid, the assays being completed within half an hour. The method showed high reproducibility, good sensitivity with detection limits of 0.078 to 0.625 mg/L except for miconazole and econazole, and high recovery rates of 86-l05%. Out of 24 therapeutic agents tested only aztreonam and trimethoprim were found to interfere with the assay of 5-flucytosine and fluconazole respectively, using this protocol. HPLC assay should be useful in the clinical laboratory for monitoring patients on antifungal therapy.

Mechanisms of the stereoselective interaction between miconazole and racemic warfarin in human subjects.

Miconazole decreased the total body clearance of both (R)- and (S)-warfarin in normal subjects but did not change volumes of distribution. Miconazole inhibited the oxidation of both (R)- and (S)-warfarin to phenolic metabolites, although (S)-warfarin was inhibited to the greater extent. In particular, (S)-7-hydroxylation, the pathway primarily responsible for termination of the anticoagulant effect, was most strongly inhibited. Inhibition of warfarin hydroxylation by miconazole in human liver microsomes and the in vivo results showed a good rank order correlation. The enhanced anticoagulant effect observed when miconazole and warfarin are coadministered may result from inhibition of P4502C9, the isozyme of P450 primarily responsible for the conversion of (S)-warfarin to (S)-7-hydroxy-warfarin. Because miconazole inhibits a number of P450 isozymes, in addition to P4502C9, it can be expected to lead to interactions with other drugs whose primary metabolism is controlled by these enzymes.

Systemic absorption of miconazole from the vagina.

The serum concentrations of miconazole were measured in 11 healthy adult females for 72 hours following a single 1200 mg vaginal pessary. The mean peak serum miconazole concentration was 10.4 micrograms/l and the mean elimination half life was 56.8 h. The mean area under the serum concentration time curve was 967 micrograms/l.h. The calculated mean systemic bioavailability of the vaginal pessary was 1.4%. There was large intersubject variation in serum miconazole pharmacokinetics. This formulation may provide effective single dose treatment for vaginal candidosis.

The measurement of serum 5-fluorocytosine levels in the presence of miconazole.

Miconazole is effective against a wide variety of fungi, and may be of value when used in combination with 5-fluorocytosine in the treatment of life-threatening mycotic infections. Because the hematologic toxicity of 5-fluorocytosine is related to high serum levels, the effects of miconazole on the standard disc diffusion assay for 5-fluorocytosine were studied. When standards were made in either undiluted or 10% pooled human serum, no difference in zone size between 5-fluorocytosine alone and the combination of 5-fluorocytosine and miconazole was found. It is concluded that, in this assay system, miconazole does not affect the disc diffusion test for serum 5-fluorocytosine levels.