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\u202fh. 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

Regenerated keratin membrane to match the in vitro drug diffusion through human epidermis

AbstractThis work aimed to develop membranes made of regenerated keratin and ceramides (CERs) to match the barrier property of the human stratum corneum in in vitro percutaneous absorption studies. The membrane composition was optimized on the basis of the in vitro drug diffusion profiles of ibuprofen, propranolol and testosterone chosen as model drugs on the basis of their different diffusion and solubility properties. The data were compared to those obtained using human epidermis.The ATR-FTIR and SEM analyses revealed that CERs were suspended into the regenerated keratin matrix, even if a partial solubilization occurred. It resulted in the membranes being physically stable after exposure to aqueous buffer and/or mineral oil and the fluxes of ibuprofen and propranolol from these vehicles through membranes and human skin were of the same order of magnitude. The best relationship with human epidermis data was obtained with 180μm-thick membrane containing 1% ceramide III and 1% ceramide VI. The data on the testosterone diffusion were affected by the exposure of the membrane to a water/ethanol solution over a prolonged period of time, indicating that such an organic solvent was able to modify the supermolecular organization of keratin and CERs.The keratin/CER membranes can represent a simplified model to assay the in vitro skin permeability study of small molecules

Applications of Alginates in the Design and Preparation of Orodispersible Dosage Forms

Orodispersible dosage forms are attractive and innovative drug delivery systems that can fulfill individual patient needs, especially in children, elderly and among dysphagic patients. Indeed, they rapidly disperse in the mouth upon contact with the saliva without the need for water or munching. Examples of such dosage forms include orodispersible tablets (ODT), and orodispersible films (ODF). The ability to obtain ODF with different dimensions (sizes and thicknesses) makes them a suitable for personalized dosing of single or a fixed-dose combination of drugs in special patient populations. Several biopolymers are currently being exploited in the development of orodispersible dosage forms including alginates due to their versatility, availability, naturally occurring, and biosafety profile. This chapter provides an appraisal on the various applications of alginates in the preparations and their role on the properties of orodispersible dosage forms and highlights future perspectives of this very versatile biopolymer for these innovative drug delivery systems

Accelerated polymer biodegradation of risperidone poly(D, L-lactide-co-glycolide) microspheres

The influence of a tertiary amine, namely risperidone (pKa = 7.9) on the degradation of poly(D, L lactide-co-glycolide) (PLGA) microspheres was elucidated. Risperidone and blank microspheres were fabricated at two lactide/glycolide ratios, 65:35 and 85:15. The microspheres were characterized for drug loading by high-performance liquid chromatography, particle size by laser diffractometry, and surface morphology by scanning electron microscopy. Polymer degradation studies were carried out with drug-loaded microspheres and blank microspheres in presence of free risperidone in 0.02 M PBS containing 0.02% Tween®80 at 37°C. Molecular weight was monitored by gel permeation chromatography. Risperidone and blank microspheres had similar size distribution and were spherical with a relatively nonporous smooth surface. The presence of risperidone within the microspheres enhanced the hydrolytic degradation in both polymeric matrices with faster degradation occurring in 65:35 PLGA. The molecular weight decreased according to pseudo-first-order kinetics for all the formulations. During the degradation study, the surface morphology of drug-loaded microspheres was affected by the presence of risperidone and resulted in shriveled microspheres in which there appeared to be an intrabatch variation with the larger microspheres being less shriveled than the smaller ones. When blank microspheres were incubated in free risperidone solutions, a concentration-dependent effect on the development of surface porosity could be observed. Risperidone accelerates the hydrolytic degradation of PLGA, presumably within the microenvironment of the drug-loaded particles, and this phenomenon must be taken into consideration in designing PLGA dosage forms of tertiary amine drugs

Spotlight on Calcipotriol/Betamethasone Fixed-Dose Combination in Topical Formulations: Is There Still Room for Innovation?

Psoriasis is a lifelong disease which requires treatment adherence for successful management. Considering the complexity of this pathology, the combination of active pharmaceutical ingredients with a synergistic mechanism of action can improve the safety and efficacy of the treatment with respect to the conventional monotherapy. Moreover, a fixed dose of therapeutic agents in a topical formulation offers the possibility to simplify administration, reduce the doses of each active ingredient, and improve patient’s compliance. Among the first-line treatments in mild to moderate psoriasis, the formulation of calcipotriol (Cal) and betamethasone dipropionate (BD) in a single vehicle is challenging due to their chemical incompatibility in an aqueous environment and the formation of degradation products. Based on these considerations, this review aims to provide an overview on the biopharmaceutical properties of Cal/BD fixed-dose combination products available on the market (namely ointment, oleogel, foam, and O/W cream), highlighting also the novel approaches under evaluation. The main differences among topical formulations are discussed considering the different features of the anatomic districts involved in psoriasis and the patient’s adherence. Moreover, since in vitro experiments are fundamental to evaluate the skin permeation profile during the development of an efficacious medicinal product, special emphasis is given to models proposed to mimic psoriatic lesions

Erratum to: Injectability Evaluation: an Open Issue

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Alternatives When an Authorized Medicinal Product is Not Available

The industrialization of medicinal products has permitted us to reach important results in terms of quality, efficacy, safety, and availability of drugs; however, not all the legitimate expectations of patients are met. When an authorized medicinal product is not available on the market, the physician can prescribe other pharmacological treatments in the following scenario: off-label prescriptions, extemporaneous preparations, compassionate use of medicinal products, and medicinal products authorized in foreign countries. The best solution among these alternatives should be evaluated case-by-case on the basis of good scientific evidence, expert medical judgement, and published literature, also keeping an eye on the availability, the cost, and the regulatory requirements at a national level

Removal of Cu(II) ions from water using thermally-treated horn–hoof powder as biosorbent

In this work, thermally-treated horn-hoof powder was studied as biosorbent to remove copper (II) ions from aqueous solutions. Adsorption of copper onto horn-hoof powder was tested in batch process at different experimental conditions. The effect of the initial metal ion concentration, biosorbent dosage, contact time, pH and temperature were investigated with respect to the biosorption characteristics of Cu(II) ion on the horn-hoof powder. The biosorbent characterization was carried out by Fourier transform infrared spectroscopy, mini-cell electrophoresis, BET and particle sizing analysis. According to the tests, the adsorption equilibrium time was reached within 48h and the optimum adsorption of Cu(II) ions took place at the pH value of 5.5. The Langmuir adsorption isotherm was successfully applied to the biosorption process of Cu(II) ions onto horn-hoof powder. The thermodynamic and kinetic data suggested that the biosorption process is an endothermic process involving chemical reactions and following a pseudo-second-order model

Data on spray-drying processing to optimize the yield of materials sensitive to heat and moisture content

Full dataset used to evaluate the spray-drying process parameters on the preparation of a micronized powder made of maltodextrin (MDX) is herein reported. The process parameters (namely, feed flow rate (FFR); inlet temperature (Tin); nozzle pressure (PN); noozle diameter (DN) and difference of pressure between cyclone and chamber (ΔP)) were screened through a Central Composite Design (25−1; 2∗5; nC=2) using the following responses: product yield, powder size and size dispersity (span) and the outlet temperature of the exhausted air (Tout). Data indicate that, in the considered range, only the product yield and the powder median diameter were influenced by the process. The product yield progressively increased on increasing inlet temperature and decreasing the amount or the size of droplets to be dried. The powder median diameter was positively influenced only by the nozzle diameter. This data presented in this article completes a wider work related on “Maltodextrins as drying auxiliary agent for the preparation of easily resuspendable nanoparticles” (Magri et al., 2019). Keywords: Spray-drying, Maltodextrins, Process optimizatio

Critical Aspects in the Preparation of Extemporaneous Flecainide Acetate Oral Solution for Paediatrics

The availability of liquid oral preparations compounded by pharmacists is essential to meet paediatric needs which remain unanswered by the pharmaceutical industry. Unfortunately, compendial monographs are often not available and, in many cases, pre-formulation studies (e.g., compatibility with other excipients and solubility evaluations) are not performed in-depth, leading, in some rare cases, to the inadvertent administration of a toxic dose. In this study, the preparation of an oral liquid formulation for paediatric use, containing flecainide acetate at different strengths, was considered, taking into account the possible effects of conventionally used excipients. First, the optimal vehicle was selected based on a solubility study, evidencing some unexpected formations of precipitates. As a matter of fact, the buffers commonly used for oral solutions significantly reduced flecainide solubility, and the concomitant presence of citrate buffer and methylparaben even caused the formation of non-resuspendable crystals. Then, chemical, physical, and microbiological stability were assessed. Solutions at strengths of 10 and 20 mg/mL flecainide acetate were stable up to 8 weeks when compounded by using a 40% sucrose solution as a vehicle. Microbiological data showed that the use of methylparaben was not necessary over this time period