In vitro evaluation of the dissolution behaviour of itraconazole in bio-relevant media

Host-Guest Complexation of Itraconazole with Cyclodextrins for Bioavailability Enhancement

Itraconazole is an antifungal agent included in the triazole pharmacological classification that belongs to the BCS class II, characterized by a low solubility in an aqueous medium (of 1 ng/mL, at neutral pH), which is frequently translated in a low oral bioavailability but with a high permeability. In this sense, it is necessary to find solutions to increase/improve the solubility of itraconazole in the aqueous environment. The main purpose of this study is the preparation and analysis of five different guest-host inclusion complexes containing intraconazole. Initially, a blind docking process was carried out to determine the interactions between itraconazole and the selected cyclodextrins. The second step of the study was to find out if the active pharmaceutical ingredient was entrapped in the cavity of the cyclodextrin, by using spectroscopic and thermal techniques. Also, the antifungal activity of the inclusion complexes was studied to examine if the entrapment of itraconazole influences the therapeutic effect. The results showed that the active substance was entrapped in the cavity of the cyclodextrins, with a molar ratio of 1:3 (itraconazole-cyclodextrin), and that the therapeutic effect was not influenced by the entrapment.

Pediatric tinea capitis in Jilin Province: analyzing previous results from a new perspective

OBJECTIVES

To investigate the current etiological, diagnostic, and therapeutic characteristics of tinea capitis in children in Jilin Province.

METHODS

Sixty pediatric patients with tinea capitis were enrolled between August 2020 and December 2021. Data on calcofluor white (CFW) fluorescence microscopy, fungal culture, Wood's lamp examination, dermoscopy, treatment, and follow-up were collected and analyzed.

RESULTS

1. Of all the enrolled patients, 48 had a history of animal contact, mostly with cats and dogs. Fifty-one strains were isolated, of which 46 were Microsporum canis (M. canis). 2. All enrolled patients were examined using fluorescence microscopy, and 59 were positive. Forty-one cases of tinea alba were examined using Wood's lamp, and 38 were positive. Forty-two cases of tinea alba were examined using dermoscopy, and 39 demonstrated specific signs. Effective treatment manifested as a fading bright green fluorescence, decreased mycelial/spore load, reduced specific dermoscopic signs, and hair regrowth. 3. Treatment was terminated in 23 and 37 cases based on mycological and clinical cures, respectively. No recurrence occurred during follow-up.

CONCLUSION

1. M. canis is the predominant pathogen causing tinea capitis in children in Jilin Province. Animal contact is considered the main risk factor. 2. CFW fluorescence microscopy, Wood's lamp, and dermoscopy can be used to diagnose ringworms and follow-up patients. 3. Both mycological and clinical cures can be the endpoint of adequate treatment for tinea capitis.

Preparation and Characterization of Spray-Dried Hybrid Nanocrystal-Amorphous Solid Dispersions (HyNASDs) for Supersaturation Enhancement of a Slowly Crystallizing Drug

We prepared hybrid nanocrystal-amorphous solid dispersions (HyNASDs) to examine their supersaturation capability in the release of a poorly soluble drug, itraconazole (ITZ), a slow crystallizer during dissolution. The HyNASD formulations included a polymer (HPC: hydroxypropyl cellulose, Sol: Soluplus, or VA64: Kollidon-VA64) and a surfactant (SDS: sodium dodecyl sulfate). Additionally, the dissolution performance of the HyNASDs and ASDs was compared. To this end, wet-milled aqueous nanosuspensions containing a 1:5 ITZ:polymer mass ratio with/without SDS as well as solutions of the same ratio without SDS in dichloromethane were spray-dried. XRPD-DSC confirmed that ASDs were formed upon spray drying the solution-based feeds, whereas HyNASDs (~5-30% amorphous) were formed with the nanosuspension-based feeds. SDS aided to stabilize the ITZ nanosuspensions and increase the amorphous content in the spray-dried powders. During dissolution, up to 850% and 790% relative supersaturation values were attained by HyNASDs with and without SDS, respectively. Due to the stronger molecular interaction between ITZ-Sol than ITZ-HPC/VA64 and micellar solubilization by Sol, Sol-based HyNASDs outperformed HPC/VA64-based HyNASDs. While the ASD formulations generated greater supersaturation values (≤1670%) than HyNASDs (≤790%), this extent of supersaturation from a largely nanocrystalline formulation (HyNASD) has not been achieved before. Overall, HyNASDs could boost drug release from nanoparticle-based formulations and may render them competitive to ASDs.

Itraconazole therapy for infant hemangioma: Two case reports

BACKGROUND

Infantile hemangiomas (IHs) are the most common childhood benign tumors, showing distinctive progression characteristics and outcomes. Due to the high demand for aesthetics among parents of IH babies, early intervention is critical in some cases. β-Adrenergic blockers and corticosteroids are first-line medications for IHs, while itraconazole, an antifungal medicine, has shown positive results in recent years.

CASE SUMMARY

In the present study, itraconazole was applied to treat two IH cases. The therapeutic course lasted 80-90 d, during which the visible lesion faded by more than 90%. Moreover, no obvious side effects were reported, and the compliance of the baby and parents was desirable.

CONCLUSION

Although these outcomes further support itraconazole as an effective therapeutic choice for IHs, large-scale clinical and basic studies are still warranted to improve further treatment.

Novel cocrystals of itraconazole: Insights from phase diagrams, formation thermodynamics and solubility

In this work, the cocrystallization approach was applied to itraconazole (ITR), a very slightly soluble triazole antifungal drug, which led to the formation of two new solid forms of ITR with 4-aminobenzoic acid (4AmBA) and 4-hydroxybenzamide (4OHBZA). A thermodynamic analysis of the solid-liquid binary phase diagrams for the (ITR + 4AmBA) and (ITR + 4OHBZA) systems provided conclusive evidence of the cocrystal stoichiometry: 1:1 for the cocrystal with 4-aminobenzoic acid, and 1:2 for the cocrystal with 4-hydroxybenzamide. Powder X-Ray diffraction analysis confirmed the formation of two different polymorphic forms of the [ITR + 4OHBZA] (1:2) cocrystal obtained either through solution or melt crystallization. Cocrystal formation and polymorphic transition processes were investigated in detail by the DSC and HSM methods. The thermodynamic functions of cocrystal formation were estimated from the solubility of the cocrystals and the corresponding solubility of the pure compounds at different temperatures. The combination of ITR and 4OHBZA was found to be more favorable than the reaction between ITR and 4AmBA in terms of both Gibbs energy and enthalpy. The pH-solubility behavior of the cocrystals was investigated at different pH values using eutectic concentrations of the components and the cocrystal solubility advantage was estimated. It was found that the cocrystallization of itraconazole with 4OHBZA and 4AmBA can potentially increase the drug solubility at pH1.2 and 37 °C by 225 and 64 times, respectively. The cocrystal dissolution behavior in biorelevant media was analyzed in terms of C_max, σ_max parameters (the maximum ITR concentration and supersaturation), and AUC (the concentration area under the curve during the dissolution - supersaturation - precipitation process). The cocrystals had similar σ_max values during the dissolution and sustained supersaturation for up to 6 h, which gave them an advantage in the AUC values (13-37 times higher) over the drug. The differences in the dissolution profiles of the cocrystals were rationalized in terms of their dissolution rate values.

pH-Responsive copolymer micelles to enhance itraconazole efficacy against Candida albicans biofilms

Candida albicans (C. albicans) is a common fungal pathogen causing both localised and systemic infections. The majority of these infections are promoted by biofilm formation, providing a protective matrix for the embedded fungi thereby evading the host immune defence and promoting resistance against anti-mycotic agents. In this study, pH-responsive micellar systems based on poly-(ethylene glycol) ethyl ether methacrylate (PEGMA) and poly 2-(diethylamino) ethyl methacrylate (DEAEMA) block-copolymers of P(PEGMA-b-DEAEMA) were specifically developed and loaded with the antifungal itraconazole (ICZ) to defeat C. albicans biofilms. The P(PEGMA-b-DEAEMA) di-block polymer micelles demonstrated a particle size of 55 ± 6 nm and high ICZ loads (12.0 ± 0.5% w/w). Within the biofilm's acidic microenvironment, tertiary amines of the pH-sensitive DEAEMA block are protonated, altering their conformation and enhancing the release of the micellar contents. Encapsulation of ICZ within micelles significantly enhanced the activity against C. albicans biofilms, with a significant reduction in the biofilm biomass (>50%) and in the number of viable cells (2.4 Log reduction) achieved, compared with the non-encapsulated ICZ. Confocal microscopy revealed a high affinity and accumulation of the micelles in C. albicans biofilms as a result of their size and specific electrostatic interaction, hence their improved activity. P(PEGMA-b-DEAEMA) based pH-responsive micelles offer significant potential as antifungal carriers for controlling Candida infections.

Biorelevant release testing of biodegradable microspheres intended for intra-articular administration

Characterization of controlled release formulations used for intra-articular (IA) drug administration is challenging. Bio-relevant synovial fluids (BSF), containing physiologically relevant amounts of hyaluronic acid, phospholipids and proteins, were recently proposed to simulate healthy and osteoarthritic conditions. This work aims to evaluate the performance of different controlled release formulations of methylprednisolone (MP) for IA administration, under healthy and disease states simulated conditions. Microspheres differed in grade of poly(lactide-co-glycolide) and in the theoretical drug content (i.e. 23 or 30% w/w). Their performance was compared with the commercially available suspension of MP acetate (MPA). Under osteoarthritic state simulated condition, proteins increased the MPA release and reduced the MPA hydrolysis rate, over 48 h. Regarding microspheres, the release patterns over 40 days were significantly influenced by the composition of BSF. The pattern of the release mechanism and the amount released was affected by the presence of proteins. Protein concentration affected the release and the concentration used is critical, particularly given the relevance of the concentrations to target patient populations, i.e. patients with osteoarthritis.

Transfer Behavior of the Weakly Acidic BCS Class II Drug Valsartan from the Stomach to the Small Intestine During Fasted and Fed States

The objective of this study was to investigate the transfer behavior of the weakly acidic BCS class II drug valsartan from the stomach to the small intestine during fasted and fed states. An in vitro transfer model previously introduced by Kostewicz et al. (J Pharm Pharmacol 56(1):43-51, 2004) based on a syringe pump and a USP paddle apparatus was used to determine the concentration profiles of valsartan in the small intestine. Donor phases of simulated gastric fluid during fasted (FaSSGF) and fed (FeSSGF) states were used to predisperse Diovan® tablets (160 mg valsartan). The initial concentrations of valsartan in FaSSGF and FeSSGF were 6.2 and 91.8%, respectively. Valsartan dispersions were then transferred to acceptor phases that simulate intestinal fluid and cover the physiological properties (pH, buffer capacity, and ionic strength) of the gastrointestinal fluid at a flow rate of 2 mL/min. The pH measurements were reported at time intervals corresponded to those of the transfer experiments to investigate the effect of percent dissolved of valsartan in the donor phase on lowering the pH of the acceptor phases. The f2 similarity test was used to compare the concentration profiles in the acceptor phases. In fasted state, the concentration of valsartan in the acceptor phases ranged between 33.1 and 89.4% after 240 min. Whereas in fed state, valsartan was fully dissolved in all acceptor phases within a range of 94.5-104.9% after 240 min. Therefore, the transfer model provides a useful screen for the concentrations of valsartan in the small intestine during fasted and fed states.

Polymer⁻Surfactant System Based Amorphous Solid Dispersion: Precipitation Inhibition and Bioavailability Enhancement of Itraconazole

The rapid release of poorly water-soluble drugs from amorphous solid dispersion (ASD) is often associated with the generation of supersaturated solution, which provides a strong driving force for precipitation and results in reduced absorption. Precipitation inhibitors, such as polymers and surfactants, are usually used to stabilize the supersaturated solution by blocking the way of kinetic or thermodynamic crystal growth. To evaluate the combined effect of polymers and surfactants on maintaining the supersaturated state of itraconazole (ITZ), various surfactants were integrated with enteric polymer hydroxypropyl methylcellulose acetate succinate (HPMC AS) to develop polymer⁻surfactant based solid dispersion. The supersaturation stability was investigated by in vitro supersaturation dissolution test and nucleation induction time measurement. Compared to the ASD prepared with HPMC AS alone, the addition of d-alpha-tocopheryl polyethylene glycol 1000 succinate (TPGS) exhibited a synergistic effect on precipitation inhibition. The results indicated that the TPGS not only significantly reduced the degree of supersaturation which is the driving force for precipitation, but also provided steric hindrance to delay crystal growth by absorbing onto the surface of small particles. Subsequently, the formulations were evaluated in vivo in beagle dogs. Compared with commercial product Sporanox®, the formulation prepared with HPMC AS/TPGS exhibited a 1.8-fold increase in the AUC (0⁻24 h) of ITZ and a 1.43-fold increase of hydroxyitraconazole (OH-ITZ) in the plasma. Similarly, the extent of absorption was increased by more than 40% when compared to the formulation prepared with HPMC AS alone. The results of this study demonstrated that the ASD based on polymer⁻surfactant system could obviously inhibit drug precipitation in vitro and in vivo, which provides a new access for the development of ASD for poorly water-soluble drug.

High payload itraconazole-incorporated lipid nanoparticles with modulated release property for oral and parenteral administration

OBJECTIVES

The aim of this study was to develop high payload itraconazole-incorporated lipid nanoparticles (HINP) with modulated release property using a binary mixture core of solid and liquid lipid for oral and parenteral administration.

METHODS

High payload itraconazole-incorporated lipid nanoparticles were prepared by hot high-pressure homogenization method using tristearin (TS) as a solid lipid, triolein (TO) as a liquid lipid and egg phosphatidylcholine/Tween 80/DSPE-PEG₂₀₀₀ as a surfactants mixture. To investigate the effects of liquid lipid in lipid core on itraconazole (ITZ) dissolution and release, TS/TO ratio was varied as 100/0, 90/10 and 80/20 (mg/mg).

KEY FINDINGS

All HINP formulations showed particle size around 300 nm and polydispersity index below 0.3. The incorporation efficiencies of HINP formulations were above 80%, and more than 40 mg of ITZ was incorporated into each HINP formulation. In-vitro dissolution and release rate of ITZ from HINP increased as the amount of TO in lipid core increased. Compared with commercial formulations of ITZ, the pharmacokinetics of ITZ was improved after oral and parenteral administration of HINP formulations containing 0% or 10% of TO in lipid core.

CONCLUSION

High payload itraconazole-incorporated lipid nanoparticles with a binary mixture lipid core have a great potential for the development of controlled release formulation of ITZ.

Investigation of a suitable in vitro dissolution test for itraconazole-based solid dispersions

The difficulty to find a relevant in vitro dissolution test to evaluate poorly soluble drugs is a well-known issue. One way to enhance their aqueous solubility is to formulate them as amorphous solid dispersions. In this study, three formulations containing itraconazole (ITZ), a model drug, were tested in seven different conditions (different USP apparatuses and different media). Two of the formulations were amorphous solid dispersions namely Sporanox®, the marketed product, and extrudates composed of Soluplus® and ITZ produced by hot melt extrusion; and the last one was pure crystalline ITZ capsules. After each test, a ranking of the formulations was established. Surprisingly, the two amorphous solid dispersions exhibited very different behavior depending primarily on the dissolution media. Indeed, the extrudates showed a better release profile than Sporanox® in non-sink and in biphasic conditions, whilst Sporanox® showed a higher release profile than the extrudates in sink and fasted simulated gastric conditions. The disintegration, dynamic light scattering and nuclear magnetic resonance results highlighted the presence of interaction between the surfactants and Soluplus®, which slowed down the erosion of the polymer matrix. Indeed, the negative charge of sodium dodecyl sulfate (SDS) and bile salts interacted with the surface of the extrudates that formed a barrier through which the water hardly diffused. Moreover, Soluplus® and SDS formed mixed micelles in solution in which ITZ interacts with SDS, but no longer with Soluplus®. Regarding the biphasic dissolution test, the interactions between the octanol dissolved in the aqueous media disrupted the polymer--ITZ system leading to a reduced release of ITZ from Sporanox®, whilst it had no influence on the extrudates. All together these results pointed out the difficulty of finding a suitable in vitro dissolution test due to interactions between the excipients that complicates the prediction of the behavior of these solid dispersions in vivo.

Administration of Oral Itraconazole Capsule with Whole Milk Shows Enhanced Efficacy As Supported by Scanning Electron Microscopy in a Child with Tinea Capitis Due to Microsporum canis

Although diagnosis and treatment of tinea capitis in children are not difficult, treatment failures are still somewhat common. We report a case of pediatric tinea capitis cured using oral itraconazole administered with whole milk, after prior treatment failure when oral itraconazole was administered with water. This apparent enhanced efficacy in one individual was demonstrated using scanning electron microscopy.

The impact of food components on the intrinsic dissolution rate of ketoconazole

To accurately predict the in vivo performance of drugs from an in vitro dissolution test, the dissolution conditions used are supposed to be similar to those present in the gastrointestinal milieu. Post-prandial gastric fluid contains partially digested food mixtures consisting of fat, protein and carbohydrate. Despite this, the compendia dissolution medium recommended to simulate the gastric fluid is still composed of a simple solution of hydrochloric acid and sodium chloride with or without the addition of pepsin. Therefore, in this investigation, biorelevant dissolution media were developed to evaluate the impact of food constituents; milk with different fat contents, egg albumin, gelatin, casein, gluten, carbohydrates and amino acids on the intrinsic dissolution behavior of ketoconazole. Most of the food additives that were evaluated enhanced the apparent solubility of the drug but to different extents. The greatest enhancement in dissolution was observed in media containing either neutral amino acids or media based on milk mixtures. The formation of complexes between the drug and the additives most likely accounted for the solubilizing effect and in milk-containing media, the effect was attributed to the whole complex structure of milk rather than simply its fat content. These results highlight the potential effect of the type of ingested meal on drug dissolution and subsequent bioavailability.

Lyophilized phytosomal nanocarriers as platforms for enhanced diosmin delivery: optimization and ex vivo permeation

Diosmin (DSN) is an outstanding phlebotonic flavonoid with a tolerable potential for the treatment of colon and hepatocellular carcinoma. Being highly insoluble, DSN bioavailability suffers from high inter-subject variation due to variable degrees of permeation. This work endeavored to develop novel DSN loaded phytosomes in order to improve drug dissolution and intestinal permeability. Three preparation methods (solvent evaporation, salting out, and lyophilization) were compared. Nanocarrier optimization encompassed different soybean phospholipid (SPC) types, different solvents, and different DSN:SPC molar ratios (1:1, 1:2, and 1:4). In vitro appraisal encompassed differential scanning calorimetry, infrared spectroscopy, particle size, zeta potential, polydispersity index, transmission electron microscopy, drug content, and in vitro stability. Comparative dissolution studies were performed under sink versus non-sink conditions. Ex vivo intestinal permeation studies were performed on rats utilizing noneverted sac technique and high-performance liquid chromatography analysis. The results revealed lyophilization as the optimum preparation technique using SPC and solvent mixture (Dimethyl sulphoxide:t-butylalchol) in a 1:2 ratio. Complex formation was contended by differential scanning calorimetry and infrared data. Optimal lyophilized phytosomal nanocarriers (LPNs) exhibited the lowest particle size (316 nm), adequate zeta-potential (-27 mV), and good in vitro stability. Well formed, discrete vesicles were revealed by transmission electron microscopy, drug content, and in vitro stability. Comparative dissolution studies were performed. LPNs demonstrated significant enhancement in DSN dissolution compared to crude drug, physical mixture, and generic and brand DSN products. Permeation studies revealed 80% DSN permeated from LPNs via oxygenated rat intestine compared to non-detectable amounts from suspension. In this study, LPNs (99% drug loading) could be successfully tailored for DSN with improved dissolution and permeation characteristics, which is promising for lowering the influence of exogenous factors and increasing drug delivery.

Lyophilized phytosomal nanocarriers as platforms for enhanced diosmin delivery: optimization and ex vivo permeation

Diosmin (DSN) is an outstanding phlebotonic flavonoid with a tolerable potential for the treatment of colon and hepatocellular carcinoma. Being highly insoluble, DSN bioavailability suffers from high inter-subject variation due to variable degrees of permeation. This work endeavored to develop novel DSN loaded phytosomes in order to improve drug dissolution and intestinal permeability. Three preparation methods (solvent evaporation, salting out, and lyophilization) were compared. Nanocarrier optimization encompassed different soybean phospholipid (SPC) types, different solvents, and different DSN:SPC molar ratios (1:1, 1:2, and 1:4). In vitro appraisal encompassed differential scanning calorimetry, infrared spectroscopy, particle size, zeta potential, polydispersity index, transmission electron microscopy, drug content, and in vitro stability. Comparative dissolution studies were performed under sink versus non-sink conditions. Ex vivo intestinal permeation studies were performed on rats utilizing noneverted sac technique and high-performance liquid chromatography analysis. The results revealed lyophilization as the optimum preparation technique using SPC and solvent mixture (Dimethyl sulphoxide:t-butylalchol) in a 1:2 ratio. Complex formation was contended by differential scanning calorimetry and infrared data. Optimal lyophilized phytosomal nanocarriers (LPNs) exhibited the lowest particle size (316 nm), adequate zeta-potential (-27 mV), and good in vitro stability. Well formed, discrete vesicles were revealed by transmission electron microscopy, drug content, and in vitro stability. Comparative dissolution studies were performed. LPNs demonstrated significant enhancement in DSN dissolution compared to crude drug, physical mixture, and generic and brand DSN products. Permeation studies revealed 80% DSN permeated from LPNs via oxygenated rat intestine compared to non-detectable amounts from suspension. In this study, LPNs (99% drug loading) could be successfully tailored for DSN with improved dissolution and permeation characteristics, which is promising for lowering the influence of exogenous factors and increasing drug delivery.

Development and validation of a discriminative dissolution test for betamethasone sodium phosphate and betamethasone dipropionate intramuscular injectable suspension

The intramuscular administration of the injectable suspension betamethasone sodium phosphate (BSP) and betamethasone dipropionate (BD) has immediate therapeutic activity due to solubilized BSP and prolonged activity resulting from the slow release of BD micro-crystals. The purpose of this study was to develop and validate a dissolution method for BD in intramuscular injectable suspensions with detection by high-performance liquid chromatography (HPLC) method. Five commercial products presented a distribution of particle sizes, ranging between 7.43 and 40.25 μm as measured by laser diffraction. It was also found that particle sizes differed between batches of the same product. The different products were tested using the paddle apparatus, with stirring speeds of 25 and 50 rpm in 300 mL of phosphate buffer; simulated body fluid, muscle fluid, and synovial fluid were used as biorelevant dissolution media at 37±0.5°C. It was verified that not only does average particle size affect the dissolution rate, but also the mode and the polydispersity index of the particles. Discriminatory power was obtained using the in vitro dissolution method with 0.1 M sodium phosphate buffer pH 7.4 containing 0.1% sodium lauryl sulfate and a stirring speed of 50 rpm. The HPLC-method is linear, precise, selective, and accurate for the quantification of BSP and BD in dissolution profile testing. This dissolution method can be utilized as a method to control the quality of these injectable suspensions.