Formulation, optimization and evaluation of spray-dried mucoadhesive microspheres as intranasal carriers for Valsartan

Visualization of nasal powder distribution using biomimetic human nasal cavity model

Nasal drug delivery efficiency is highly dependent on the position in which the drug is deposited in the nasal cavity. However, no reliable method is currently available to assess its impact on delivery performance. In this study, a biomimetic nasal model based on three-dimensional (3D) reconstruction and three-dimensional printing (3DP) technology was developed for visualizing the deposition of drug powders in the nasal cavity. The results showed significant differences in cavity area and volume and powder distribution in the anterior part of the biomimetic nasal model of Chinese males and females. The nasal cavity model was modified with dimethicone and validated to be suitable for the deposition test. The experimental device produced the most satisfactory results with five spray times. Furthermore, particle sizes and spray angles were found to significantly affect the experimental device's performance and alter drug distribution, respectively. Additionally, mometasone furoate (MF) nasal spray (NS) distribution patterns were investigated in a goat nasal cavity model and three male goat noses, confirming the in vitro and in vivo correlation. In conclusion, the developed human nasal structure biomimetic device has the potential to be a valuable tool for assessing nasal drug delivery system deposition and distribution.

Application of Intranasal Administration in the Delivery of Antidepressant Active Ingredients

As a mental disease in modern society, depression shows an increasing occurrence, with low cure rate and high recurrence rate. It has become the most disabling disease in the world. At present, the treatment of depression is mainly based on drug therapy combined with psychological therapy, physical therapy, and other adjuvant therapy methods. Antidepressants are primarily administered peripherally (oral and intravenous) and have a slow onset of action. Antidepressant active ingredients, such as neuropeptides, natural active ingredients, and some chemical agents, are limited by factors such as the blood–brain barrier (BBB), first-pass metabolism, and extensive adverse effects caused by systemic administration. The potential anatomical link between the non-invasive nose–brain pathway and the lesion site of depression may provide a more attractive option for the delivery of antidepressant active ingredients. The purpose of this article is to describe the specific link between intranasal administration and depression, the challenges of intranasal administration, as well as studies of intranasal administration of antidepressant active ingredients.

Intranasal delivery of biotechnology-based therapeutics

Biotechnology-based therapeutics include a wide range of products, such as recombinant hormones, stem cells, therapeutic enzymes, monoclonal antibodies, genes, vaccines, among others. The administration of these macromolecules has been studied via various routes. The nasal route is one of the promising routes of administration for biotechnology products owing to its easy delivery, the rich vascularity of the nasal mucosa, high absorption and targeted action. Several preclinical studies have been reported for nasal delivery of these products and many are at the clinical stage. This review focuses on biotechnology-based therapeutics administered via the intranasal route for treating various diseases.

New and developing pharmacotherapies for hypertension

INTRODUCTION

Despite the significant contribution of hypertension to the global burden of disease, disease control remains poor worldwide. Considering this unmet clinical need, several new antihypertensive drugs with novel mechanisms of action are under development.

AREAS COVERED

The present review summarizes the recent advances in the development of emerging pharmacological agents for the management of hypertension. The latest technological innovations in the design of optimized formulations of available antihypertensive drugs and the potential role of the modification of intestinal microbiota to improve blood pressure (BP) control are also covered.

EXPERT OPINION

Significant efforts have been made to develop new antihypertensive agents with novel actions that target the main mechanisms involved in resistant hypertension. Sacubitril/valsartan may emerge as a potential first-line drug due to its superiority over renin angiotensin system inhibitors, and SGLT2 inhibitors can reduce BP in difficult-to-control hypertensive patients with type 2 diabetes. In addition, firibastat and aprocitentan may expand the therapeutic options for resistant hypertension by novel mechanism of actions. Since gut dysbiosis not only leads to hypertension but also causes direct target organ damage, prebiotics and probiotics could represent a potential strategy to prevent or reduce the development of hypertension and to contribute to BP control.

Spray dried powders for nasal delivery: Process and formulation considerations

Powders for nasal delivery have been recognized as advantageous dosage forms over liquids due to increased stability and residence time on nasal mucosa, with improved bioavailability. They can be manufactured by spray-drying, allowing the optimization of the particle properties that are critical to guarantee nasal deposition, as size and shape. It is also a scalable and flexible method already explored extensively in the pharmaceutical industry. However, it is important to understand how process parameters, particle physical properties and formulation considerations affect the product performance. Hence, this review aims to provide an overview of nasal powder formulation and processing through spray drying, with an emphasis on the variables that impact on performance. To this purpose, we describe the physical, biological and pharmacological phenomena prior to drug absorption as well as the most relevant powder properties. Formulation considerations including qualitative and quantitative composition are then reviewed, as well as manufacturing considerations including spray drying relevant parameters.

Chitosan coated synergistically engineered nanoemulsion of Ropinirole and nigella oil in the management of Parkinson's disease: Formulation perspective and In vitro and In vivo assessment

The research presented aims at developing Ropinirole hydrochloride (RHCl) nanoemulsion (NE) with nigella oil for Parkinson's disease (PD). In silico study was done to explore interactions of ropinirole and thymoquinone at receptor site (TNF-α and NFK-β). Ropinirole and Thymoquinone forms a hydrogen bond with residue Arginine 201 and residue Arginine 253 with a bond length of 1.89 Å and 2.30 Å at the NF-κβ receptor. NE was optimized using Central Composite Rotatable Design (CCRD). The globule size of chitosan coated NE, Polydispersity index (PDI) and zeta potential were 183.7 ± 5.2 nm, 0.263 ± 0.005, and 24.9 mV respectively. NE exhibited 85.28% transmittance showing the formulation was clear and transparent. TEM showed that NE had spherical globules with no aggregation. The formulation had a stable pH value of 5.8 ± 0.18. In vitro release and permeation studies exhibited 2 folds and 3.4 folds enhancement when compared with the drug suspension. Neurobehavioral activity and biochemical parameters corroborated well with the pharmacokinetic results. Histopathological study and immunohistochemical analysis were performed to get better picture of 6-OHDA induced toxicity and reversal of PD symptoms. Thus, the NE tailored is a promising synergistic approach yielding enticing outcomes for better management of PD related symptoms.

Brain targeting of resveratrol through intranasal lipid vesicles labelled with gold nanoparticles: in vivo evaluation and bioaccumulation investigation using computed tomography and histopathological examination

Resveratrol is a promising neuroprotective agent against neurodegenerative disorders such as Alzheimer's disease. Resveratrol-loaded transferosomes and nanoemulsions were developed and labelled with gold nanoparticles (GNPs). The water maze test was utilised to identify the effect on spatial memory recovery. The treated rats were examined for cellular uptake and bioaccumulation of drug in the brain using computed tomography (CT) and histopathological examination utilising GNPs as a biomarker. Compared with nanoemulsions, transferosomes displayed higher permeation of up to 81.29 ± 2.64% and higher fluorescence intensity with p < .05. Transferosomes significantly enhanced behavioural acquisition and spatial memory function in the amnesic rats compared with both the nanoemulsion formulation and the pure drug. CT effectively demonstrated the accumulation of GNPs in the brains of all treated rats, while superior accumulation of GNPs was observed in the rats that received the transferosome formulation. The histopathology also demonstrated GNP accumulation in the nuclei and cytoplasm in the brain tissues of both the transferosome- and nanoemulsion-treated groups. Therefore, the developed transferosomes may be considered as a well-designed brain targeting system that might further be applied for targeting many drugs to be used in the treatment of central nervous system diseases.

Opportunity and challenges of nasal powders: Drug formulation and delivery

In the field of nasal drug delivery, among the preparations defined by the European Pharmacopoeia, nasal powders facilitate the formulation of poorly water-soluble active compounds. They often display a simple composition in excipients (if any), allow for the administration of larger drug doses and enhance drug diffusion and absorption across the mucosa, improving bioavailability compared to nasal liquids. Despite the positive features, however, nasal products in this form still struggle to enter the market: the few available on the market are Onzetra Xsail® (sumatriptan) for migraine relief and, for the treatment of rhinitis, Rhinocort® Turbuhaler® (budesonide), Teijin Rhinocort® (beclomethasone dipropionate) and Erizas® (dexamethasone cipecilate). Hence, this review tries to understand why nasal powder formulations are still less common than liquid ones by analyzing whether this depends on the lack of (i) real evidence of superior therapeutic benefit of powders, (ii) therapeutic and/or commercial interest, (iii) efficient manufacturing methods or (iv) availability of suitable and affordable delivery devices. To this purpose, the reader's attention will be guided through nasal powder formulation strategies and manufacturing techniques, eventually giving up-to-date evidences of therapeutic efficacy in vivo. Advancements in the technology of insufflation devices will also be provided as nasal drug products are typical drug-device combinations.

Formulation of olfactory-targeted microparticles with tamarind seed polysaccharide to improve nose-to-brain transport of drugs

Targeted delivery and retention of drug formulations in the olfactory mucosa, the target site for nose-to-brain drug absorption is a major challenge due to the geometrical complexity of the nose and nasal clearance. Recent modelling data indicates that 10μm-sized microparticles show maximum deposition in the olfactory mucosa. In the present study we tested the hypothesis that 10μm-sized mucoadhesive microparticles would preferentially deposit on, and increase retention of drug on, the olfactory mucosa in a novel 3D-printed human nasal-replica cast under simulated breathing. The naturally occurring mucoadhesive polymer, tamarind seed polysaccharide (TSP) was used to formulate the microparticles using a spray drying technique. Physicochemical properties of microparticles such as size, morphology and mucoadhesiveness was investigated using a combination of laser diffraction, electron microscopy and texture-analysis. Furthermore, FITC-dextrans (5-40kDa) were incorporated in TSP-microparticles as model drugs. Size-dependent permeability of the FITC-dextrans was observed ex vivo using porcine nasal mucosa. Using the human nasal-replica cast, greater deposition of 10μm TSP-microparticles in the olfactory region was observed compared to TSP-microparticles 2μm in size. Collectively, these findings support our hypothesis that 10μm-sized mucoadhesive microparticles can achieve selective deposition and retention of drug in the olfactory mucosa.

Ropinirole-dextran sulfate nanoplex for nasal administration against Parkinson's disease: in silico molecular modeling and in vitro-ex vivo evaluation

Dextran sulfate sodium (DS) was allowed to interact ionically with ropinirole hydrochloride (ROPI HCl, an anti-Parkinsonian agent) to synthesize self-assembled ROPI-DS nanoplex. The preliminary objective behind ROPI-DS complexation was to enhance the partitioning of ROPI HCl and thereby its encapsulation into nanocarriers and to improve the nasal membrane permeability. Molecular interactions were computed using in silico molecular modeling. Nanoplex were characterized for physicochemical and partitioning behavior. Optimized ROPI-DS nanoplex was further characterized by spectroscopic and thermal analysis, diffraction studies, morphological and histopathological analysis. In summary, ROPI-DS nanoplex represents a promising nanocarrier material for intranasal administration.

New nasal nanocomplex self-assembled from charged biomacromolecules: N,N,N-Trimethyl chitosan and dextran sulfate

Although chitosan (CHT, a linear cationic polysaccharide) is biodegradable, biocompatible, non-toxic, and mucoadhesive in nature, the low solubility of CHT in aqueous and alkaline media limits its applicability in pharmaceutical and biomedical field. This necessitate the introduction of new chemically-modified derivatives of CHT those can surmount the solubility barrier. Herein, N,N,N-trimethyl chitosan (TMC), a quaternized hydrophilic derivative of CHT, was synthesized by two-step reductive methylation of CHT and characterized for (1)H NMR and zeta potential measurements. Polyelectrolyte complexes (PECs) based on TMC and dextran sulfate (DS) were prepared via ionic interactions between charged functional groups of former polysaccharides at different pH conditions (pH 5, 8, 10, and 12) and characterized for physicochemical (particle size and zeta potential) and solid- state characterizations (HR-TEM, SEM, FTIR, TGA and XRD). At alkaline pH conditions, the participant polymer chains (TMC and DS) are sufficiently close to form more stable PECs. The release efficiency was assessed after loading a model drug into optimized PEC formulation. Data indicated that the PECs fabricated at alkaline pH presents a reliable formulation for pharmaceutical and biomedical applications.

Nanotechnology-mediated nose to brain drug delivery for Parkinson's disease: a mini review

Nose to brain delivery of neurotherapeutics have been tried by several researchers to explore the virtues of this route viz. circumvention of BBB, avoidance of hepatic metabolism, practicality, safety, ease of administration and non-invasiveness. Nanoparticle (NP) therapeutics is an emerging modality for the treatment of Parkinson's disease (PD) as it offers targeted delivery and enhances the therapeutic efficacy and/or bioavailability of neurotherapeutics. This review presents a concise incursion into the nanomedicines suitable for PD therapy delivered via naso-brain transport. Clinical signs of PD, its pathophysiology, specific genetic determinants, diagnosis and therapy involved have been hashed out. Properties of brain-targeting NPs, transport efficacy and various nanocarriers developed so far also been furnished. In our opinion, nanotechnology-enabled naso-brain drug delivery is an excellent means of delivering neurotherapeutics and is a promising avenue for researchers to develop new formulations for the effective management of PD.

Novel surface modified polymer-lipid hybrid nanoparticles as intranasal carriers for ropinirole hydrochloride: in vitro, ex vivo and in vivo pharmacodynamic evaluation

Here we report fabrication and evaluation of novel surface modified polymer-lipid hybrid nanoparticles (PLN) as robust carriers for intranasal delivery of ropinirole hydrochloride (ROPI HCl). Sustained release, avoidance of hepatic first pass metabolism, and improved therapeutic efficacy are the major objectives of this experiment. PLN were fabricated by emulsification-solvent diffusion technique and evaluated for physicochemical parameters, in vitro mucoadhesion, in vitro diffusion, ex vivo permeation, mucosal toxicity and stability studies. Box-Behnken experimental design approach has been employed to assess the influence of two independent variables, viz. surfactant (Pluronic F-68) and charge modifier (stearylamine) concentration on particle size, ζ-potential and entrapment efficiency of prepared PLN. Numerical optimization techniques were used for selecting optimized formulation sample, further confirmed by three dimensional response surface plots and regression equations. Results of ANOVA demonstrated the significance of suggested models. DSC and SEM analysis revealed the encapsulation of amorphous form of drug into PLN system, and spherical shape. PLN formulation had shown good retention with no severe signs of damage on integrity of nasal mucosa. Release pattern of drug-loaded sample was best fitted to zero order kinetic model with non-Fickian super case II diffusion mechanism. In vivo pharmacodynamic studies were executed to compare therapeutic efficacy of prepared nasal PLN formulation against marketed oral formulation of same drug. In summary, the PLN could be potentially used as safe and stable carrier for intranasal delivery of ROPI HCl, especially in treatment of Parkinson's disease.

Bioavailability enhancement of verapamil HCl via intranasal chitosan microspheres

Chitosan microspheres are potential drug carriers for maximizing nasal residence time, circumventing rapid mucociliary clearance and enhancing nasal absorption. The aim of the present study was to develop and characterize chitosan mucoadhesive microspheres of verapamil hydrochloride (VRP) for intranasal delivery as an alternative to oral VRP which suffers low bioavailability (20%) due to extensive first pass effect. The microspheres were produced using a spray-drying and precipitation techniques and characterized for morphology (scanning electron microscopy), particle size (laser diffraction method), drug entrapment efficiency, thermal behavior (differential scanning calorimetry) and crystallinity (X-ray diffractometric studies) as well as in vitro drug release. Bioavailability of nasal VRP microspheres was studied in rabbits and the results were compared to those obtained after nasal, oral and intravenous administration of VRP solution. Results demonstrated that the microspheres were spherical with size 21-53 μm suitable for nasal deposition. The spray-drying technique was superior over precipitation technique in providing higher VRP entrapment efficiency and smaller burst release followed by a more sustained one over 6h. The bioavailability study demonstrated that the nasal microspheres exhibited a significantly higher bioavailability (58.6%) than nasal solution of VRP (47.8%) and oral VRP solution (13%). In conclusion, the chitosan-based nasal VRP microspheres are promising for enhancing VRP bioavailability by increasing the nasal residence time and avoiding the first-pass metabolism of the drug substance.

Formulation and in vitro evaluation of salbutamol sulphate in situ gelling nasal inserts

The aim of this study was to formulate salbutamol sulfate (SS), a model drug, as mucoadhesive in situ gelling inserts having a high potential as nasal drug delivery system bypassing the first-pass metabolism. In situ gelling inserts, each containing 1.4% SS and 2% gel-forming polymer, hydroxypropyl methylcellulose (HPMC), carboxymethylcellulose sodium (CMC Na), sodium alginate (AL), and chitosan (CH) were prepared. The inserts were investigated for their different physicochemical properties. The weight of inserts was 16-27 mg, drug content was 3.9-4.2 mg, thickness ranged between 15 and 28 μm and surface pH was 5-7. Cumulative drug released from the inserts exhibited extended release for more than 10 h following the decreasing order: CH>AL>CMC Na>HPMC. The drug release from CMC Na and AL inserts followed zero-order kinetics while HPMC and CH inserts exhibited non-Fickian diffusion mechanism. The inserts exhibited different water uptake (7-23%) with the smallest values for CH. Differential scanning calorimetry study pointed out possible interaction of SS and oppositely charged anionic polymers (CMC Na and AL). The mucoadhesive in situ gelling inserts exhibited satisfactory mucoadhesive and extended drug release characteristics. The inserts could be used for nasal delivery of SS over about 12 h; bypassing the hepatic first-pass metabolism without potential irritation.

Fabrication and statistical optimization of surface engineered PLGA nanoparticles for naso-brain delivery of ropinirole hydrochloride: in-vitro-ex-vivo studies

Ropinirole hydrochloride (RPN), a nonergot dopamine D2-agonist used in the management of Parkinson's disease, has poor oral bioavailability (52%) due to extensive hepatic metabolism. The intent of present research work was aimed at design and statistical optimization of RPN-loaded poly (lactic-co-glycolic acid) (PLGA)-based biodegradable nanoparticles (NPs) surface modified using natural emulsifier, vitamin E (d-α-tocopheryl polyethylene glycol 1000 succinate [TPGS]) for direct nose-to-brain delivery in order to avoid hepatic first-pass metabolism, and improve therapeutic efficacy with sustained drug release. RPN-NPs were prepared by modified nanoprecipitation technique and optimized using 2(3) factorial design of experiment. The effect of polymer and emulsifier concentration was evaluated on particle size and entrapment efficiency (EE%). Formulation PL6 was considered as desirable with highest EE% (72.3 ± 6.1%), PS (279.4 ± 1.8 nm), zeta potential (-29.4 ± 2.6 mV), and cumulative drug diffusion of 96.43 ± 3.1% in 24 h. The ANOVA results for the dependent variables demonstrated that the model was significant (p value < 0.05) for response variables. Histopathological study of optimized batch (PL6) demonstrated good retention of NPs with no severe signs of damage on the integrity of nasal mucosa. Differential scanning calorimetry revealed the absence of any chemical interaction between RPN, PLGA, and TPGS while SEM study confirmed spherical shape of optimized NPs. Accelerated stability studies of freeze-dried optimized batch demonstrated negligible change in the average PS and EE% after storage at 25 ± 2 °C/60 ± 5% (relative humidity (RH) for the period of three months. The promising results of optimized batch suggested practicability of investigated system for enhancement of bioavailability and brain targeting of CNS acting drugs like RPN.

Direct nose to brain drug delivery via integrated nerve pathways bypassing the blood-brain barrier: an excellent platform for brain targeting

INTRODUCTION

The blood-brain barrier (BBB) represents a stringent barrier for delivery of neurotherapeutics in vivo. An attempt to overcome this barrier is represented by the direct transport of drugs from the nose to the brain along the olfactory and trigeminal nerve pathways. These nerve pathways initiate in the nasal cavity at olfactory neuroepithelium and terminate in the brain. An enormous range of neurotherapeutics, both macromolecules and low molecular weight drugs, can be delivered to the central nervous system (CNS) via this route.

AREAS COVERED

Present review highlights the literature on the anatomy-physiology of the nasal cavity, pathways and mechanisms of neurotherapeutic transport across nasal epithelium and their biofate and various strategies to enhance direct nose to brain drug delivery. The authors also emphasize a variety of drug molecules and carrier systems delivered via this route for treating CNS disorders. Patents related to direct nose to brain drug delivery systems have also been listed.

EXPERT OPINION

Direct nose to brain drug delivery system is a practical, safe, non-invasive and convenient form of formulation strategy and could be viewed as an excellent alternative approach to conventional dosage forms. Existence of a direct transport route from the nasal cavity to the brain, bypassing the BBB, would offer an exciting mode of delivering neurotherapeutic agents.