Screening and verification of CYP3A4 inhibitors from Bushen-Yizhi formula to enhance the bioavailability of osthole in rat plasma.

ETHNOPHARMACOLOGICAL RELEVANCE: With the features of multiple-components and targets as well as multifunction, traditional Chinese medicine (TCM) has been widely used in the prevention and treatment of various diseases for a long time. During the application of TCM, the researches about bioavailability enhancement of the bioactive constituents in formula are flourishing. Bushen-Yizhi formula (BSYZ), a TCM prescription with osthole (OST) as one of the main bioactive ingredients, have been widely used to treat kidney deficiency, mental retardation and Alzheimer's disease. However, the underlying biological mechanism and compound-enzyme interaction mediated bioavailability enhancement of OST are still not clearly illuminated. AIM OF THE STUDY: The aim of this study is to explore the material basis and molecular mechanism from BSYZ in the bioavailability enhancement of OST. Screening the potential CYP3A4 inhibitors using theoretical prediction and then verifying them in vitro, and pharmacokinetics study of OST in rat plasma under co-administrated of screened CYP3A4 inhibitors and BSYZ were also scarcely reported. MATERIALS AND METHODS: Screening of CYP3A4 inhibitors from BSYZ was performed with molecular docking simulation from systems pharmacology database. The screened compounds were verified by using P450-Glo Screening Systems. A multiple reaction monitoring (MRM) mass spectrometry method was established for OST quantification. Male Sprague-Dawley rats divided into four groups and six rats in each group were employed in the pharmacokinetics study of OST. The administrated conditions were group I, OST (20 mg/kg); group II, BSYZ (containing OST 1 mg/mL, at the dose of 20 mg/kg OST in BSYZ); group III, co-administration of ketoconazole (Ket, 75 mg/kg) and OST (20 mg/kg); group IV, co-administration of CYP3A4 inhibitor (10 mg/kg) and OST (20 mg/kg). They were determined by using HPLC-MS/MS (MRM) and statistical analysis was performed using student's t-test with p < 0.05 as the level of significance. RESULTS: 21 potential CYP3A4 inhibitors were screened from BSYZ compounds library. From the results of verification in vitro, we found 4 compounds with better CYP3A4 inhibition efficiency including Oleic acid, 1,2,3,4,6-O-Pentagalloylglucose, Rutin, and Schisantherin B. Under further verification, Schisantherin B exhibited the best inhibitory effect on CYP3A4 (IC50 = 0.339 µM), and even better than the clinically used drug (Ket) at the concentration of 5 µM. In the study of pharmacokinetics, the area under the curve (AUC, ng/L*h) of OST after oral administration of BSYZ, Ket and Schisantherin B (2196.23 ± 581.33, 462.90 ± 92.30 and 1053.03 ± 263.62, respectively) were significantly higher than that of pure OST treatment (227.89 ± 107.90, p < 0.01). CONCLUSIONS: Schisantherin B, a profoundly effective CYP3A4 inhibitor screened from BSYZ antagonized the metabolism of CYP3A4 on OST via activity inhibition, therefore significantly enhanced the bioavailability of OST in rat plasma. The results of this study will be helpful to explain the rationality of the compatibility in TCM formula, and also to develop new TCM formula with more reasonable drug compatibility.

In Vitro-In Vivo Correlation in Cocrystal Dissolution: Consideration of Drug Release Profiles Based on Coformer Dissolution and Absorption Behavior.

This study assessed the in vitro-in vivo correlation in cocrystal dissolution based on the coformer behavior. 4-Aminobenzoic acid (4ABA) was used as a coformer. Cocrystals of poorly water-soluble drugs with 4ABA, ketoconazole cocrystal (KTZ-4ABA), posaconazole cocrystal (PSZ-4ABA), and itraconazole cocrystal (ITZ-4ABA) were used. These three cocrystals generated supersaturated solutions in fasted state simulated intestinal fluid (FaSSIF) in a small-scale, 8 mL dissolution vessel. The time profile of the dissolved amount of 4ABA, an indicator of cocrystal dissolution, was significantly different among the three cocrystals. Under the conditions utilized, half of the KTZ-4ABA cocrystal solid rapidly dissolved within 5 min and the dissolved amount (% of applied amount) of KTZ and 4ABA was the same. Then, even though the residual solid cocrystal gradually dissolved, KTZ precipitated with time. The PSZ-4ABA cocrystal dissolved in a linear fashion with time but the dissolved concentration of PSZ reached a plateau in the supersaturated state and was maintained for at least 2 h. The dissolution rate of ITZ-4ABA was very slow compared to those of the other cocrystals, but a similar tendency was observed between cocrystal dissolution and the dissolved amount of ITZ. The rank order of the cocrystal dissolution rate based on the conformer concentration was KTZ-4ABA > PSZ-4ABA > ITZ-4ABA. Furthermore, cocrystallization of the three drugs with 4ABA significantly enhanced the oral drug absorption in rats. The rank order of the in vivo cocrystal dissolution rate by a deconvolution analysis with the plasma concentration-time profile of 4ABA was KTZ-4ABA > PSZ-4ABA > ITZ-4ABA, which corresponded well with the in vitro dissolution profiles of the cocrystals. These results indicate that analysis of cocrystal dissolution based on the coformer behavior may be useful to evaluate the in vitro and in vivo cocrystal dissolution.

Topical application of nanoparticles integrated supramolecular hydrogels for the potential treatment of seborrhoeic dermatitis.

The current application was aimed to evaluate the therapeutic potential of selenium and ketoconazole nanoparticles loaded hyaluronic acid gel against seborrhoeic dermatitis (SD). Amalgamation of ketoconazole (antifungal medication) and selenium (pro-oxidant) in an optimized formulation setting may help in the treatment of SD. In this study, selenium and ketoconazole nanoparticles loaded hyaluronic acid (HA) hydrogel was prepared by mechanical mixing followed by sonication. Results of the optimized batch showed a mean particle size of 121 ± 12 nm for ketoconazole and 51 ± 7 nm for selenium. SEM and TEM study revealed the prepared nanoparticles are of nanoscale dimension, with smooth spherical outline. Finally, the optimized nanoparticles were incorporated into HA hydrogel. Hydrogel exhibits desirable physical, mechanical and rheological characteristics appropriate for topical application. Optimized gel formulation exhibited an enhanced permeability with better antifungal, and anti-inflammatory activities, compared with the plain drug suspension. The optimized hydrogel with ketoconazole and selenium in nanotemplate could offer a potential strategy for the treatment of SD.

Formulation evaluation of ketoconazole microemulsion-loaded hydrogel with nigella oil as a penetration enhancer.

BACKGROUND: Onychomycosis is an opportunistic fungal infection often infecting people with compromised immune system. Currently available treatment interventions such as physical, surgical, and chemical-based approaches are successful in treating the condition, however, are painful and nonpatient complaint. Moreover, dermal creams with antifungal agents do not penetrate nail plate as required; hence, there is a necessity of developing a novel formulation with enhanced penetration. AIMS: The aim of the present research work was to develop ketoconazole microemulsion-loaded hydrogel formulation containing nigella oil as permeation enhancer for the treatment of onychomycosis. METHODS: Screening of oils, surfactants, and cosurfactants were done based on solubility studies followed by the construction of pseudo-ternary phase diagrams with 2% ketoconazole. The microemulsion was characterized for globule size, zeta potential, viscosity, and thermodynamic stability. Ex-vivo studies were carried out using Franz diffusion cells using porcine skin membrane. The antifungal activity of microemulsion-loaded hydrogel was evaluated using cup plate method using Candida albicans and Aspergillus niger. RESULTS: The optimized microemulsion had a composition of 54.97% Capryol:Nigella (2:1), 36.07% Transcutol:Propylene glycol (2:1), and 7.13% water and was later incorporated into polymeric gel base. The microemulsion-loaded hydrogel exhibited a 10 hours sustained release profile as compared to the marketed cream and an enhanced activity against marketed ketoconazole cream and compared with marketed ketoconazole formulation. CONCLUSION: The thermodynamic stability, sustained drug release with greater permeation, and enhanced activity due to the presence of nigella oil in microemulsion-loaded hydrogel warrant its application as an excellent vehicle for treating fungal infections.

Oxythiamine improves antifungal activity of ketoconazole evaluated in canine Malassezia pachydermatis strains.

BACKGROUND: Malassezia pachydermatis is an opportunistic yeast involved in skin and ear canal infections of dogs and cats. Reports suggest that strains of M. pachydermatis resistant to commonly used antifungal agents may be emerging. Therefore, new therapeutic strategies should be explored. OBJECTIVES: The synergistic effect of oxythiamine (OT) and ketoconazole (KTC) was analysed using a reference strain and field isolates (n = 66) of M. pachydermatis. Hydrogel formulations containing these components also were evaluated. METHODS AND MATERIALS: The minimum inhibitory concentrations (MICs) and minimum fungicidal concentrations (MFCs) of OT, KTC and their mixtures were determined by a broth macrodilution method. The antifungal effects of hydrogel formulations were determined by a plate diffusion method. RESULTS: The MIC and MFC values of OT were in the range 0.08 × 103 to 10 × 103  mg/L. All M. pachydermatis strains showed higher susceptibility to KTC (MICs and MFCs in the range 0.04-0.32 mg/L). Formulations that combined OT and KTC showed a synergistic effect for all tested isolates (n = 66). Hydrogels that contained OT at a concentration of 10 × 103 or 20 × 103  mg/L and KTC at the concentration of 0.1 × 103  mg/L showed a stronger effect than a commercially available product with KTC alone (20 × 103  mg/L). CONCLUSIONS AND CLINICAL IMPORTANCE: Synergy of these drugs may allow for successful topical treatment which utilizes lower doses of KTC without changing its therapeutic effectiveness. Hydrogel formulations proved to be attractive drug carriers for potential topical use.

Enhanced UV protection of ketoconazole using Hyptis suaveolens micro emulsion.

Ketoconazole is photolabile antifungal drug. Photochemical reactions may decrease its therapeutic effect or induce toxic compounds. The aim of this study was to prepare ketoconazole loaded microemulsion containing H. suaveolens oil with antifungal and antioxidant powers in order to obtain effective antifungal formulation. The release study, antifungal activity and photostability test, were then evaluated. The results showed that optimized Hyptis suaveolens microemulsion for ketoconazole loading was selected through construction of pseudo-ternary phase diagrams. It consisted of 12.5% H. suaveolens oil, 12.5% capryol, 25% tween 80, 25% ethanol and 25% water. Mean globule size was 153 nm, as analyzed by photon correlation spectroscopy. Ketoconazole-loaded Hyptis suaveolens microemulsion and Hyptis suaveolens microemulsion had antifungal activity against Candida albican, Microsporum gypseum and Trichophyton mentagrophyte, showing inhibition zone ranged from 28-37 mm and 23-32 mm, respectively. Ketoconazole was released from Hyptis suaveolens microemulsion more than 90% within 5 days. In the results of photostability test, ketoconazole-loaded Hyptis suaveolens microemulsion gave significantly higher remaining ketoconazole than ketoconazole solution. This study demonstrated that Hyptis suaveolens microemulsion could be used to improve the photoprotection of photolabile drug.

Enhancement of ketoconazole dissolution rate by the liquisolid technique.

The study was conducted to enhance the dissolution rate of ketoconazole (KCZ) (a poorly water-soluble drug) using the liquisolid technique. Microcrystalline cellulose, colloidal silica, PEG400 and polyvinyl pyrrolidone (PVP) were employed as a carrier, coating substance, nonvolatile solvent and additive in the KCZ liquisolid compact formulation, respectively. The drug-to-PEG400 and carrier-to-coating ratio variations, PVP concentration and aging effects on the in vitro release behavior were assessed. Differential scanning calorimetry (DSC) and X-ray powder diffraction (XRD) data revealed no alterations in the crystalline form of the drug and the KCZ-excipient interactions within the process. The load factor and the drug release rate were significantly enhanced compared to directly compressed tablets in the presence of the additive. Increasing the PEG400-to-drug ratio in liquid medications enhanced the dissolution rate remarkably. The dissolution profile and hardness of liquisolid compacts were not significantly altered by keeping the tablets at 40 °C and relative humidity of 75 % for 6 months. With the proposed modification of the liquisolid process, it is possible to obtain flowable, compactible liquisolid powders of high-dose poorly-water soluble drugs with an enhanced dissolution rate.

Absorption, Metabolic Stability, and Pharmacokinetics of Ginger Phytochemicals.

We have previously demonstrated promising anticancer efficacy of orally-fed whole ginger extract (GE) in preclinical prostate models emphasizing the importance of preservation of the natural "milieu". Essentially, GE primarily includes active ginger phenolics viz., 6-gingerol (6G), 8-gingerol (8G), 10-gingerol (10G), and 6-shogaol (6S). However, the druglikeness properties of active GE phenolics like solubility, stability, and metabolic characteristics are poorly understood. Herein, we determined the physicochemical and biochemical properties of GE phenolics by conducting in vitro assays and mouse pharmacokinetic studies with and without co-administration of ketoconazole (KTZ). GE phenolics showed low to moderate solubility in various pH buffers but were stable in simulated gastric and intestinal fluids, indicating their suitability for oral administration. All GE phenolics were metabolically unstable and showed high intrinsic clearance in mouse, rat, dog, and human liver microsomes. Upon oral administration of 250 mg/kg GE, sub-therapeutic concentrations of GE phenolics were observed. Treatment of plasma samples with ß-glucuronidase (ßgd) increased the exposure of all GE phenolics by 10 to 700-fold. Co-administration of KTZ with GE increased the exposure of free GE phenolics by 3 to 60-fold. Interestingly, when the same samples were treated with ßgd, the exposure of GE phenolics increased by 11 to 60-fold, suggesting inhibition of phase I metabolism by KTZ but little effect on glucuronide conjugation. Correlating the in vitro and in vivo results, it is reasonable to conclude that phase II metabolism seems to be the predominant clearance pathway for GE phenolics. We present evidence that the first-pass metabolism, particularly glucuronide conjugation of GE phenolics, underlies low systemic exposure.

Topical Treatment of Facial Seborrheic Dermatitis: A Systematic Review.

BACKGROUND: Facial seborrheic dermatitis (SD), a chronic inflammatory skin condition, can impact quality of life, and relapses can be frequent. Three broad categories of agents are used to treat SD: antifungal agents, keratolytics, and corticosteroids. Topical therapies are the first line of defense in treating this condition. OBJECTIVE: Our objective was to critically review the published literature on topical treatments for facial SD. METHODS: We searched PubMed, Scopus, Clinicaltrials.gov, MEDLINE, Embase, and Cochrane library databases for original clinical studies evaluating topical treatments for SD. We then conducted both a critical analysis of the selected studies by grading the evidence and a qualitative comparison of results among and within studies. RESULTS: A total of 32 studies were eligible for inclusion, encompassing 18 topical treatments for facial SD. Pimecrolimus, the focus of seven of the 32 eligible studies, was the most commonly studied topical treatment. CONCLUSION: Promiseb®, desonide, mometasone furoate, and pimecrolimus were found to be effective topical treatments for facial SD, as they had the lowest recurrence rate, highest clearance rate, and the lowest severity scores (e.g., erythema, scaling, and pruritus), respectively. Ciclopirox olamine, ketoconazole, lithium (gluconate and succinate), and tacrolimus are also strongly recommended (level A recommendations) topical treatments for facial SD, as they are consistently effective across high-quality trials (randomized controlled trials).

Role of Metabolic Activation in 8-Epidiosbulbin E Acetate-Induced Liver Injury: Mechanism of Action of the Hepatotoxic Furanoid.

8-Epidiosbulbin E acetate (EEA), a furanoid, was unexpectedly found to be the most abundant diterpenoid lactone in certain varieties of Dioscorea bulbifera L. (DB), a traditional herbal medicine widely used in Asian nations. This herb has been reported to cause liver injury in humans and experimental animals. The occurrence of EEA in DB was dependent on its commercial source. The present study shows that EEA exhibits time- and dose-dependent liver injury in mice. Pretreatment with ketoconazole prevented the animals from developing EEA-induced liver injury, caused 7- and 13-fold increases in the plasma Cmax and AUC of EEA, and decreased urinary excretion of glutathione conjugates derived from EEA. Pretreatment with buthionine sulfoximine exacerbated EEA-induced hepatotoxicity. In order to define the role of EEA's furan moiety in EEA-induced hepatotoxicity, we synthesized tetrahydro-EEA by catalytic hydrogenation of the furan moiety. No liver injury was observed in the animals given the same doses of tetrahydro-EEA as those used with EAA. The results indicate that EEA itself does not appear to be hepatotoxic but that the electrophilic intermediate generated by the metabolic activation of the furan ring mediated by cytochromes P450 is responsible for EEA-induced liver injury.

Best practices for the use of itraconazole as a replacement for ketoconazole in drug-drug interaction studies.

Ketoconazole has been widely used as a strong cytochrome P450 (CYP) 3A (CYP3A) inhibitor in drug-drug interaction (DDI) studies. However, the US Food and Drug Administration has recommended limiting the use of ketoconazole to cases in which no alternative therapies exist, and the European Medicines Agency has recommended the suspension of its marketing authorizations because of the potential for serious safety concerns. In this review, the Innovation and Quality in Pharmaceutical Development's Clinical Pharmacology Leadership Group (CPLG) provides a compelling rationale for the use of itraconazole as a replacement for ketoconazole in clinical DDI studies and provides recommendations on the best practices for the use of itraconazole in such studies. Various factors considered in the recommendations include the choice of itraconazole dosage form, administration in the fasted or fed state, the dose and duration of itraconazole administration, the timing of substrate and itraconazole coadministration, and measurement of itraconazole and metabolite plasma concentrations, among others. The CPLG's recommendations are based on careful review of available literature and internal industry experiences.

Preclinical assessment of the interactions between the antiretroviral drugs, ritonavir and efavirenz, and the tyrosine kinase inhibitor erlotinib.

PURPOSE: Prevalence of non-AIDS-defining cancers (NADCs) has increased in the era of potent antiretroviral treatments. Incidence rates of NADCs now exceed AIDS-defining cancers in HIV-positive patients. Treatment of NADCs may be complicated by interactions between antiretrovirals and chemotherapy mostly via inhibition or induction of CYP3A4. Erlotinib is used to treat non-small cell lung and pancreatic cancer and is primarily metabolized by CYP3A4 into multiple products including the active metabolite (OSI-420). Preclinical in vivo assessment was performed to gain a better understanding of CYP3A4-mediated interactions between antiretrovirals and erlotinib. METHODS: Erlotinib (50 mg/kg p.o.) was administered to male FVB mice in the presence and absence of dexamethasone (10 mg/kg p.o. QDx4), efavirenz (25 mg/kg p.o. QDx4), ketoconazole (50 mg/kg p.o.), or ritonavir (12.5 mg/kg p.o.). Blood samples were collected to characterize exposure (AUC). RESULTS: Administration of erlotinib with CYP3A4 inducers (dexamethasone) and inhibitors (ketoconazole and ritonavir) resulted in significant alterations in erlotinib exposure. Ketoconazole and ritonavir resulted in a 1.7- and 3.0-fold increase in erlotinib AUC, respectively, while dexamethasone results in a 0.6-fold decrease in erlotinib AUC. The CYP3A4 inducer efavirenz did not have a significant effect on erlotinib exposure. CONCLUSION: CYP3A4 inducers and inhibitors altered the exposure of erlotinib. Until a definitive clinical trial is performed, erlotinib should be used with caution in patients on a ritonavir-containing antiretroviral regimen, while standard doses may be appropriate for patients on an efavirenz-containing antiretroviral regimen.

The combination of amoxicillin-clavulanic acid and ketoconazole in the treatment of Madurella mycetomatis eumycetoma and Staphylococcus aureus co-infection.

Eumycetoma is a chronic progressive disabling and destructive inflammatory disease which is commonly caused by the fungus Madurella mycetomatis. It is characterized by the formation of multiple discharging sinuses. It is usually treated by antifungal agents but it is assumed that the therapeutic efficiency of these agents is reduced by the co-existence of Staphylococcus aureus co-infection developing in these sinuses. This prospective study was conducted to investigate the safety, efficacy and clinical outcome of combined antibiotic and antifungal therapy in eumycetoma patients with superimposed Staphylococcus aureus infection. The study enrolled 337 patients with confirmed M. mycetomatis eumycetoma and S. aureus co-infection. Patients were allocated into three groups; 142 patients received amoxicillin-clavulanic acid and ketoconazole, 93 patients received ciprofloxacin and ketoconazole and 102 patients received ketoconazole only. The study showed that, patients who received amoxicillin-clavulanic acid and ketoconazole treatment had an overall better clinical outcome compared to those who had combined ciprofloxacin and ketoconazole or to those who received ketoconazole only. In this study, 60.6% of the combined amoxicillin-clavulanic acid/ketoconazole group showed complete or partial clinical response to treatment compared to 30.1% in the ciprofloxacin/ketoconazole group and 36.3% in the ketoconazole only group. The study also showed that 64.5% of the patients in the ciprofloxacin/ketoconazole group and 59.8% in the ketoconazole only group had progressive disease and poor outcome. This study showed that the combination of amoxicillin-clavulanic acid and ketoconazole treatment is safe and offers good clinical outcome and it is therefore recommended to treat eumycetoma patients with Staphylococcus aureus co-infection.

Efficacy of topical 4% Quassia amara gel in facial seborrheic dermatitis:a randomized, double-blind, comparative study.

BACKGROUND: Seborrheic dermatitis (SD) is a chronic mild skin disorder with high prevalence. Various treatment options are available, including topical antifungals and anti-inflammatories. Antifungal and anti-inflammatory properties of Quassia amara have been reported. AIM: To check the efficacy and safety of a topical gel with 4% Quassia amara extract and compare it with topical 2% ketoconazole and 1% topical ciclopiroxolamine in the treatment of facial SD. METHODS: A group of 60 patients displaying facial SD were randomly distributed in 3 groups and given either a topical gel with 4% Quassia amara extract, a topical gel with 2% ketoconazole, or a topical gel with 1% ciclopirox olamine for 4 weeks. Disease severity was assessed at the start and weekly along treatment, as well as 4 weeks after the end of treatment. In each selected area, severity of erythema, scaling, pruritus, and papules were scored from 0 to 3, the sum of these values representing the score of SD on the face. This evaluation was conducted at each visit. The decrease in SD score with all 3 products was compared at each visit. At each stage, overall improvement, safety, and tolerability were also assessed. RESULTS: Of the 60 patients, 54 (90%) completed the study. The 3 therapeutic options resulted to be very effective, with a significant advantage in efficacy for 4% Quassia extract. For the other 2 drugs, the results were in line with those previously published in the literature. CONCLUSION: Topical gel with 4% Quassia extract represents a new, safe, and effective treatment for facial SD.

A conceptually new treatment approach for relapsed glioblastoma: coordinated undermining of survival paths with nine repurposed drugs (CUSP9) by the International Initiative for Accelerated Improvement of Glioblastoma Care.

To improve prognosis in recurrent glioblastoma we developed a treatment protocol based on a combination of drugs not traditionally thought of as cytotoxic chemotherapy agents but that have a robust history of being well-tolerated and are already marketed and used for other non-cancer indications. Focus was on adding drugs which met these criteria: a) were pharmacologically well characterized, b) had low likelihood of adding to patient side effect burden, c) had evidence for interfering with a recognized, well-characterized growth promoting element of glioblastoma, and d) were coordinated, as an ensemble had reasonable likelihood of concerted activity against key biological features of glioblastoma growth. We found nine drugs meeting these criteria and propose adding them to continuous low dose temozolomide, a currently accepted treatment for relapsed glioblastoma, in patients with recurrent disease after primary treatment with the Stupp Protocol. The nine adjuvant drug regimen, Coordinated Undermining of Survival Paths, CUSP9, then are aprepitant, artesunate, auranofin, captopril, copper gluconate, disulfiram, ketoconazole, nelfinavir, sertraline, to be added to continuous low dose temozolomide. We discuss each drug in turn and the specific rationale for use- how each drug is expected to retard glioblastoma growth and undermine glioblastoma's compensatory mechanisms engaged during temozolomide treatment. The risks of pharmacological interactions and why we believe this drug mix will increase both quality of life and overall survival are reviewed.

In vivo effect of Schisandrin B on cytochrome P450 enzyme activity.

To investigate the possible drug interaction, this study is designed to evaluate the ability of Schisandrin B (Sch B) to modulate cytochrome P450 3A activity (CYP3A) in vivo and to alter the pharmacokinetic profiles of CYP3A substrate (midazolam) in treated rats. Rats were repeated administered with physiological saline (negative control group), ketoconazole (75 mg/kg, positive control group) or varied doses of Sch B (experimental groups) for three consecutive days. Subsequently, changes in hepatic microsomal CYP3A activity and the pharmacokinetic profiles of midazolam and 1'-hydroxy midazolam in plasma were studied to evaluate CYP3A activity. The results indicated that Sch B significantly dose-dependently inhibited rat hepatic microsomal CYP3A activity with Ki value of 16.64 mg/kg and showed the characteristic of a noncompetitive inhibitor. Oral administration of Sch B for 3 days in rats produced significant effect on the pharmacokinetics of oral midazolam. Sch B resulted in a significant, dose-dependent increase in midazolam AUC0-∞ except at the dose of 2 mg/kg, while AUC0-∞ increased by 26.1% (8 mg/kg) and 60.6% (16 mg/kg), respectively. In the pharmacokinetic profiles of 1'-hydroxy midazolam, the significant, dose-dependent decrease in AUC0-∞ was observed except at the dose of 2 mg/kg, while AUC0-∞ reduced by 44.5% (8 mg/kg) and 49.2% (16 mg/kg), respectively. These results suggested that 3-day treatment of Sch B could increase concentration and oral bioavailability of drug metabolized by CYP3A. When the drug, consisting of Sch B, is used in the clinic for more than 3 days, the possible drug-drug interactions should be taken into consideration.

Ketoconazole or clotrimazole solution wash as a prophylaxis in management and prevention of fungal infection: a comparative study.

The incidence of fungal infections has increased at an alarming rate in the past two decades. Topical Ketoconazole and Clotrimazole solutions are used to stop growth of fungus like Dermatophytes, Candidiasis and Pityrosporum. The objective of this study is to assess the effectiveness of prophylactic Ketoconazole or Clotrimazole solution wash in patients with fungal infections. Hundred patients (aged 10-60 yrs) with different fungal infections (Candida, Tinea, Pityriasis) were included. The study groups were divided into intervention group and control group. The Intervention group was given 5 weeks prophylactic Ketoconazole/Clotrimazole shampoo wash along with antifungal treatment whereas the control group was given only antifungal treatment without prophylaxis. All the patients were assessed at 1, 3 and 6 months interval to find out the response and recurrence. After one month of treatment 96% of patients in the intervention group and 60% of patients in the control group were completely cured. The recurrence rate after 3 mths of treatment was 4% in the intervention group and 40% in the control group. After 6 months the recurrence rate was 4% in the intervention group and 60% in the control group. The most common problem with fungal infections is the recurrence. Use of prophylactic antifungal (Ketoconazole/Clotrimazole) wash for some period of time along with antifungal treatment minimizes the chances of recurrence.

Effect of the CYP3A inhibitor ketoconazole on the PXR-mediated induction of CYP3A activity.

PURPOSE: The aim of this clinical study was to investigate a previously proposed mechanism of ketoconazole-mediated inhibition of cytochrome P450 3A (CYP3A) induction. METHODS: A two-phase, randomized, cross-over, open, mono-centre trial was carried out. Participants received ketoconazole and St John's wort for 8 days to study the proposed suppression of St John's wort-mediated induction of CYP3A at the transcriptional level. In the second phase, we studied the inhibitory effect of a single dose of ketoconazole directly at the enzyme level during CYP3A induction by St John's wort. Midazolam served as a marker substance of CYP3A activity using an established limited sampling strategy. RESULTS: After 8 days of simultaneous ketoconazole and St John's wort administration, CYP3A-mediated midazolam metabolism was strongly inhibited (81 % decrease in clearance). Following the induction of CYP3A with St John's wort (6.6-fold increase in clearance on day 8), a single dose of ketoconazole strongly inhibited midazolam metabolism to the same degree (82 % decrease in clearance in relation to baseline). An induction of midazolam metabolism was observed after discontinuation of both drugs in both study phases. These results apparently contradict the in vitro results where ketoconazole showed an inhibitory effect on the transcription of CYP3A genes. CONCLUSIONS: Ketoconazole is a strong inhibitor of CYP3A, also when used concomitantly with St John's wort. In therapeutic doses it does not inhibit pregnane X receptor-mediated induction of CYP3A in vivo.

[Outbreak of dermatophytosis in a high-level French judo team: prospective study 2006/2011. Efficacy of a therapeutic protocol introduced in 2004/2005]. / Épidémie de dermatophytoses chez les judokas du pôle France d'Orléans : étude prospective 2006/2011 et évaluation de l'efficacité des mesures instaurées en 2004/2005.

BACKGROUND: Outbreaks of dermatophytosis have been reported more and more frequently in combat sports such as wrestling and judo. Such outbreaks are difficult to treat due to the involvement of numerous actors and structures. The main aim of our study was to determine whether the use of a standardized treatment in a high-level judo team could successfully reduce the outbreak. Our secondary objectives were to study the topography of lesions and ascertain whether consultations for suspected dermatophytosis were significantly more frequent during the 4 weeks following a judo training course. MATERIALS AND METHODS: We conducted a prospective follow-up study from October 2004 to the end of June 2005 (series 1) and then from September 2006 to June 2011 (series 2) during which all new suspected cases of dermatophytosis in a judoka from Pôle France Orléans were examined at the Orléans Dermatology Department. For each consultation, we prepared a map of lesions and mycological samples, and patients received standardized treatment. RESULTS: We compared the two series and a considerable decrease was noted in dermatophytosis outbreaks after the introduction of these measures. The mean number of visits per training season was 97 for series 1 and 21.6 per training season for series 2. The mean numbers of episodes of cutaneous lesions clinically active per training season were 74 for series 1 and 16.8 for series 2. Lesions were localized mainly on the forearms, face and neck (40% for series 1 and 73% for series 2). "Waves" of visits (at least two visits per week) occurred significantly more frequently (68%) during the 4 weeks following a training period than during the rest of the year. CONCLUSION: Standardized management of this outbreak reduced the number of infectious episodes.

Malformation spectrum induced by ketoconazole after single administration to pregnant rats during the critical period - comparison with vitamin A-induced malformation spectrum.

Azole derivatives have teratogenic effects in rodents. In the present study, malformations and their sensitive windows induced by high-dose ketoconazole (KCZ), an azole derivative, without maternal toxicity were investigated. In addition, the malformation spectrum determined was compared with that induced by vitamin A palmitate (VAP). Pregnant rats were administered a single dose of KCZ by oral gavage on specific individual days from gestational days 8 to 15 (GDs 8-15). Maternal animals were subjected to necropsy on GD 20, and the obtained fetuses were examined for external, visceral and skeletal malformations. The malformation spectrum of VAP was identified from available published data (Noda, Sato, and Udaka, 1982) and a complementary study (single administration of VAP at 1 200 000 IU kg(-1) ). Embryonic lethality was observed in dams given KCZ on GDs 9-12 with peak incidence on GDs 10 and 11 with complete resorption. KCZ induced major malformations included cleft palate, digital anomalies, misshapen limbs and unique discontinuous ribs, and the sensitive window for each was identified. Compared with the malformations induced by VAP, unique malformations (e.g. discontinuous ribs by KCZ, neural tube defects by VAP), similar malformations with similar sensitive windows (e.g. digital and limb malformations) and similar malformations with different sensitive windows (e.g. embryonic lethality and cleft palate) were distinguished, suggesting that the mechanisms of several of the types of KCZ-induced malformation are related to excessive vitamin A.