Nasal Drug Administration Research Articles

Lipid Nanoparticles for Nasal/Intranasal Drug Delivery.

Studies on the development of drug delivery systems have increased because these systems have particular characteristics that allow them to improve therapeutics. Among these, lipid nanoparticles (solid lipid nanoparticles, SLNs; and nanostructured lipid carriers, NLCs) have demonstrated suitability for drug targeting. The nasal administration of drug-loaded lipid nanoparticles showed effectiveness in treating central nervous system (CNS) disorders, particularly neurodegenerative diseases, because the nasal route (also called intranasal route) allows direct nose-to-brain drug delivery by means of lipid nanoparticles. Nonetheless, the feasibility of this application remains an open field for researchers. Drawbacks must be overcome before reaching the clinic (e.g., drug absorption at subtherapeutic levels, rapid mucociliary clearance). The intranasal administration of drugs for systemic absorption is effective for treating other conditions, such as cardiovascular diseases, infections, severe pain, and menopausal syndrome. In the near future, it is expected that patients will benefit from the advantages of lipid nanoparticle-based formulations, via the nasal/intranasal route, which bypasses the blood-brain barrier (BBB), avoiding first-pass metabolism and gastrointestinal degradation. This review discusses the use of SLNs and NLCs for nasal drug administration. A brief description of the nasal route and the features of SLNs and NLCs is initially provided.

Primary Air-Liquid Interface Culture of Nasal Epithelium for Nasal Drug Delivery.

Nasal drug administration is a promising alternative to oral and parenteral administration for both local and systemic delivery of drugs. The benefits include its noninvasive nature, rapid absorption, and circumvention of first pass metabolism. Hence, the use of an in vitro model using human primary nasal epithelial cells could be key to understanding important functions and parameters of the respiratory epithelium. This model will enable investigators to address important and original research questions using a biologically relevant in vitro platform that mimics the in vivo nasal epithelial physiology. The purpose of this study was to establish, systematically characterize, and validate the use of a primary human nasal epithelium model cultured at the air-liquid interface for the study of inflammatory responses and drug transport and to simultaneously quantify drug effects on ciliary activity.

Nasal administration of drugs as a new non-invasive strategy for efficient treatment of multiple sclerosis

We investigated the efficiency of nasal drug administration as a new non-invasive treatment strategy for MS. Glatiramer Acetate (GA) and GA–Cannabidiol (CBD) combination administered in nasal delivery system (NDS) resulted in a statistically significant decrease of clinical scores and inflammatory cytokine expression in experimental autoimmune encephalomyelitis (EAE) mice. Even a suboptimal dose of Prednisolone in NDS was effective in preventing the clinical signs of the disease. Neuron regeneration was observed in the hippocampus of EAE mice treated with GA-CBD in NDS. This work shows that nasal administration improved drug efficiency and stimulates further research for a non-invasive strategy for MS.

Clinical Diagnosis of the Olfactory Nerve Transport Function

Nasal administration of macromolecular drugs (peptides, nanoparticles) has a possibility to enable a drug delivery system beyond the blood brain barrier via olfactory nerve transport. Basic research on nasal drug delivery to the brain has been well studied. However, evaluation of the olfactory nerve transport function in patients with olfactory disorders has yet to be done, although such an evaluation is important in selecting candidates for clinical trials. Current olfactory function tests are useful for the analysis of olfactory thresholds in olfaction-impaired patients. However, the usefulness of using the increase in olfactory thresholds in patients as an index for evaluating olfactory nerve damage has not been confirmed because of the difficulty in directly evaluating the viability of the peripheral olfactory nerves. Nasally administered thallium-201 migrates to the olfactory bulb, as has been shown in healthy volunteers. Furthermore, transection of olfactory nerve fibers in mice significantly decreases migration of nasally administered thallium-201 to the olfactory bulb. The migration of thallium-201 to the olfactory bulb is reduced in patients with impaired olfaction due to head trauma, upper respiratory tract infections, and chronic rhinosinusitis, relative to the values in healthy volunteers. Nasally administrating thallium-201 followed by single photon emission computed tomography, X-ray computed tomography and magnetic resonance imaging might be useful in choosing candidates for clinical trials of nasal drug delivery methods to the brain.

Onset time for pharmacologic premedication with clonidine as a nasal aerosol: a double‐blind, placebo‐controlled, randomized trial

To investigate whether nasal aerosol clonidine can reduce the onset time of preoperative sedation. Premedication is common in the pediatric population, but the optimal agent and administration route is still a matter of debate. Clonidine has many beneficial effects in the perioperative period. Clonidine nasal drops produce a similar sedative effect as after oral administration but do not reduce the onset time. Nasal aerosol administration of drugs is generally more effective than drops and an option to decrease the onset time of clonidine. Pediatric ASA status 1 and 2 patients were randomized to receive placebo (P), clonidine 3-4 μg kg(-1) (C4), or clonidine 7-8 μg kg(-1) (C7) as a nasal aerosol. Acceptance of administration, pre- and postoperative sedation, and adverse events were assessed. A total of 60 patients were enrolled with a median age of 3.5 years (range 0.7-6.9) and median weight of 14.8 kg (range 10-25). In the C7 group, 55% of the children were found adequately sedated at 30 min as compared to 32% in the C4 group (P = 0.1202). At 45 min, adequate sedation was seen in 65% of the patients in both C4 and C7 groups, which were both found to be significantly higher compared with the placebo control group (14%) (P-values = 0.0027 and 0.0013, respectively). The postoperative sedation profile did not differ between the three study groups. Clonidine administered as nasal aerosol (3-8 μg kg(-1)) was not found to achieve adequate preoperative sedation within 30 min of administration. Despite its sedative properties, no prolongation of postoperative sedation was noted compared with placebo.

Mucoadhesion; A prerequisite or a constraint in nasal drug delivery?

Nasal drug administration has frequently been proposed as the most feasible alternative to parenteral injections. This is due to the high permeability of the nasal epithelium, allowing a higher molecular mass cut-off at approximately 1000 Da and the rapid drug absorption rate with plasma drug profiles sometimes almost identical to those from intravenous injections. Nasal drug administration is presently used for local therapies within the nasal cavity. Anti-allergic drugs and nasal decongestants are the most common examples. However, nasal drug administration for systemic effects has been practiced since ancient times. Nasallyadministered psychotropic drugs by native Indians, the use of tobacco snuffs, and nasal administration of illicit drugs such as cocaine are all well known. Read more...

Administration intranasale des médicaments à visée systémique : une nouvelle voie pour les opioïdes

The intranasal delivery of drugs is widely used for the local treatment of rhinitis or nasal polyposis. This route of delivery could represent an interesting alternative for systemic drugs with low digestive absorption. The nasal mucosa acts as an anatomical obstacle hard to get over, except for compounds with low molecular weight or highly lipophilic. Among morphinic drugs, fentanyl, very lipophilic, is rapidly absorbed via intranasal administration with a bioavailability close to 90%. This route of delivery for fentanyl is a new alternative for the treatment of breakthrough pain and gives the opportunity to discuss on the interest and the limits of nasal route administration of drugs, particularly of opioids.

Carbamazepine uptake into rat brain following intra-olfactory transport

Targeting the brain via nasal administration of drugs has been studied frequently over the last few years. In this study, a suitable gel formulation was designed to provide the absorption of a highly lipophilic drug through nasal mucosa. For this purpose, carbamazepine was chosen as the model drug. Hypromellose and Carbopol were used as mucoadhesive polymers in the formulation to increase the residence time of the gel on the mucosa. The objective of this study was to confirm the existence of a transport pathway for a drug (carbamazepine) to the brain directly from the nasal cavity, by comparing the concentration of drug in the brain after intranasal (i.n.), intravenous (i.v.), and oral (p.o.) administration. A statistically significant high level of the drug was found in the brain following intranasal administration compared with the intravenous and oral routes. These findings suggested the existence of a direct transport pathway for carbamazepine from the nasal cavity to the brain. This pathway may represent a new delivery route to the brain and central nervous system of such drugs which are needed in high and rapid concentration in the brain, especially in emergencies.

The biopharmaceutical aspects of nasal mucoadhesive drug delivery.

Nasal drug administration has frequently been proposed as the most feasible alternative to parenteral injections. This is due to the high permeability of the nasal epithelium, allowing a higher molecular mass cut-off at approximately 1000 Da, and the rapid drug absorption rate with plasma drug profiles sometimes almost identical to those from intravenous injections. Despite the potential of nasal drug delivery, it has a number of limitations. In this review, the anatomy and physiology of the nasal cavity, as well as ciliary beating and mucociliary clearance as they relate to nasal drug absorption, are introduced. The rationale for nasal drug delivery and its limitations, some factors that influence nasal drug absorption, and the experimental models used in nasal drug delivery research are also reviewed. Nasal mucoadhesion as a promising method of nasal absorption enhancement is discussed, and factors that influence mucoadhesion, as well as safety of nasal mucoadhesive drug delivery systems are reviewed in detail. Nasal drug administration is presently mostly used for local therapies within the nasal cavity. Anti-allergic drugs and nasal decongestants are the most common examples. However, nasal drug administration for systemic effects has been practised since ancient times. Nasally-administered psychotropic drugs by native Americans, the use of tobacco snuffs, and nasal administration of illicit drugs such as cocaine are all well known (Illum & Davis 1992). Nowadays, the nasal cavity is being actively explored for systemic administration of other therapeutic agents, particularly peptides and proteins (Illum 1992; Edman & Björk 1992), as well as for immunization purposes (Lemoine et al 1998). To better understand the basis for nasal drug absorption and factors that can influence it, a brief review of the anatomy and physiology of the nose is appropriate.

An improved primary human nasal cell culture for the simultaneous determination of transepithelial transport and ciliary beat frequency

Abstract Objectives The aim was to establish a preclinical in-vitro system of the nasal mucosa for the simultaneous evaluation of nasal absorption and effects on ciliary activity. Methods Human nasal epithelial cells were grown in collagen-coated transport inserts with transparent polyethylene terephthalate membranes (3 μm). Transepithelial transport and ciliary beat frequency values were measured every 15 min for 1 h. Key findings The apparent permeability coefficients (Papp) for atenolol (mainly paracellular transport) and propranolol (transcellular transport) amounted to 0.1 ± 0.1 and 23.7 ± 0.6 × 10−6 cm/s, respectively, illustrating that the system can be used to discriminate between high permeability and low permeability compounds. Transport of talinolol (substrate for the P-glycoprotein efflux carrier) did not reveal polarity (0.3 ± 0.2 and 0.2 ± 0.1 × 10−6 cm/s for absorptive and secretory transport, respectively) and was not affected by verapamil (10 μm), suggesting the absence of P-glycoprotein in the nasal cell culture. No significant effects of atenolol, propranolol and talinolol on ciliary beat frequency were observed (98 ± 20% of the control condition after 60 min). Chlorocresol significantly decreased the ciliary activity but this decrease was not accompanied by effects on the transepithelial transport of atenolol, propranolol and talinolol. Conclusions A new system was developed which offers possibilities as a fast screening tool for studying the potential of compounds for nasal drug administration, since permeability and a possible cilio-toxic effect can be assessed simultaneously.

An improved primary human nasal cell culture for the simultaneous determination of transepithelial transport and ciliary beat frequency

The aim was to establish a preclinical in-vitro system of the nasal mucosa for the simultaneous evaluation of nasal absorption and effects on ciliary activity. Human nasal epithelial cells were grown in collagen-coated transport inserts with transparent polyethylene terephthalate membranes (3 mum). Transepithelial transport and ciliary beat frequency values were measured every 15 min for 1 h. The apparent permeability coefficients (P(app)) for atenolol (mainly paracellular transport) and propranolol (transcellular transport) amounted to 0.1 +/- 0.1 and 23.7 +/- 0.6 x 10(-6) cm/s, respectively, illustrating that the system can be used to discriminate between high permeability and low permeability compounds. Transport of talinolol (substrate for the P-glycoprotein efflux carrier) did not reveal polarity (0.3 +/- 0.2 and 0.2 +/- 0.1 x 10(-6) cm/s for absorptive and secretory transport, respectively) and was not affected by verapamil (10 muM), suggesting the absence of P-glycoprotein in the nasal cell culture. No significant effects of atenolol, propranolol and talinolol on ciliary beat frequency were observed (98 +/- 20% of the control condition after 60 min). Chlorocresol significantly decreased the ciliary activity but this decrease was not accompanied by effects on the transepithelial transport of atenolol, propranolol and talinolol. A new system was developed which offers possibilities as a fast screening tool for studying the potential of compounds for nasal drug administration, since permeability and a possible cilio-toxic effect can be assessed simultaneously.

Carbopol-based gels for nasal delivery of progesterone.

The purpose of this study was to investigate the nasal absorption of progesterone from carbopol-based nasal gels in rabbits. Progesterone nasal gels were prepared by dispersing carbopol 974 (1%, 1.5%, and 2%) in distilled water followed by addition of progesterone/progesterone-beta cyclodextrin complex dissolved in propylene glycol then neutralization. The potential use of beta cyclodextrin (CD) as nasal absorption enhancer by simple addition, as a physical mixture and as a complex with progesterone was investigated. The absolute bioavailability of progesterone from nasal gels in rabbits was studied by estimating the serum progesterone level by competitive solid-phase enzyme immunoassay in comparison to intravenous injection. The carbopol gel formulations produced a significant increase in bioavailability. CD complex promotes the nasal absorption of progesterone from carbopol gels as compared with gels where the CD is added by simple addition and gels which do not contain CD. This method of addition of CD as an inclusion complex in the gels could be considered as a preferred platform in nasal drug administration.

Determination of insulin in innovative formulations by means of LC coupled to fluorescence detection

A fast and simple method based on LC with fluorescence detection has been developed for the determination of insulin in innovative formulations consisting of microparticles and inserts for oral and nasal drug administration, respectively. A reverse-phase C8 column and a mobile phase composed of pH 3.7, 40 mM sodium sulphate solution and acetonitrile (24%, v/v) were employed. Using isocratic elution at 1.0 mL/min flow, analysis is completed within 7 min. Three different kinds of spray-dried microparticles were analysed, consisting of an insulin loaded core composed of chitosan salts (chitosan succinate, chitosan adipate or chitosan suberate) coated with stearic acid. Nasal inserts consisted of chitosan/hyaluronate polyelectrolyte complexes which were loaded with insulin and freeze-dried. Insulin was extracted from both the oral and nasal formulations using pH 7.4 phosphate buffer. The employment of fluorescence detection ( λ exc = 276 nm, λ em = 306 nm) granted high selectivity, with no interference from the matrix. Full method validation was performed with good results in terms of linearity (insulin concentration range 0.10–30.0 μg/mL), LOD (0.03 μg/mL) and LOQ (0.10 μg/mL), precision (R.S.D.% < 3.6) and accuracy (recovery percentage > 90.0%). Insulin content in innovative formulations, expressed as percentage w/w, resulted to be between 0.90 and 0.97 for oral innovative formulations, while an average value of 342 μg of insulin was found in a single nasal insert, in good agreement with preparative protocols.

Screening of Mucoadhesive Microparticles Containing Hydroxypropyl- Beta-Cyclodextrin for the Nasal Delivery of Risperidone

Interaction of the antipsychotic drug risperidone with hydroxypropyl-beta-cyclodextrin (HPBCD) in solution and in the solid state was studied with the aim of overcoming the limitations associated with nasal administration of low solubility drugs. Risperidone solubility studies revealed inclusion complex formation with a 1:1 stoichiometry. Low concentrations (0.1 w/v %) of hydroxypropylmethyl cellulose (HPMC) and carbomer affected risperidone solubility in water. No formation of a ternary complex was detected. The solid inclusion complex was prepared by spray drying and was characterised by thermal (DSC) and spectral (FTIR) analyses. Risperidone and the inclusion complex were loaded into microparticles by spray drying using HPMC, carbomer and HPMC/carbomer interpolymer complex (IPC) as mucoadhesive components. The microparticles were characterised with respect to drug loading, particle size distribution, thermal analysis, and zeta potential measurements. Mucoadhesive properties of the microparticles were studied by measuring the work of adhesion. Carbomer and IPC based microparticles revealed superior mucoadhesive microparticles compared to HPMC based microparticles. Drug incorporation into microparticles reduced their mucoadhesive properties, while incorporation of the cyclodextrin complex caused no additional reduction in mucoadhesion. The in vitro dissolution studies showed that formation of the inclusion complex significantly increased the risperidone dissolution rate from the microparticles, thus providing sustained drug release.

Spray-dried microspheres based on methylpyrrolidinone chitosan as new carrier for nasal administration of metoclopramide

The work purpose was to study the application of 5-methylpyrrolidinone chitosan (MPC) for preparing mucoadhesive microparticles for the nasal administration of drugs. Microspheres were produced by the spray-drying technique using MPC; metoclopramide hydrochloride (MC) was chosen as model drug. Chitosan microparticles were prepared as a comparison. The microparticles obtained were characterised (encapsulation efficiency, morphology, size and drug release behaviour). In-vitro mucoadhesive tests, swelling tests and ex-vivo studies using sheep nasal mucosa were performed. The hydrogel formation from microspheres was studied in different media and at different pHs. Microspheres are able to control the in-vitro MC release. MPC microparticles show good in-vitro mucoadhesive properties and ex-vivo controlled permeation profiles. The hydrogel formation is dependent mainly on the medium used: ionically crosslinked hydrogel was hypothesized. These in-vitro and ex-vivo preliminary results show that spray-dried microspheres based on MPC could be a suitable nasal delivery system for the administration of metoclopramide.

Can Nasal Drug Delivery Bypass the??Blood-Brain Barrier?

The connection between the nasal cavity and the CNS by the olfactory neurones has been investigated extensively during the last decades with regard to its feasibility to serve as a direct drug transport route to the CSF and brain. This drug transport route has gained much interest as it may circumvent the blood-brain barrier (BBB), which prevents some drugs from entering the brain. Approximately 100 published papers mainly reporting animal experiments were reviewed to evaluate whether the experimental design used and the results generated provided adequate pharmacokinetic information to assess whether the investigated drug was transported directly from the olfactory area to the CNS. In the analysis the large anatomical differences between the olfactory areas of animals and humans and the experimental conditions used were evaluated. The aim of this paper was to establish the actual evidence for the feasibility of this direct transport route in humans. Twelve papers presented a sound experimental design to study direct nose to CNS transport of drugs based on the authors' criteria. Of these, only two studies in rats were able to provide results that can be seen as an indication for direct transport from the nose to the CNS. No pharmacokinetic evidence could be found to support a claim that nasal administration of drugs in humans will result in an enhanced delivery to their target sites in the brain compared with intravenous administration of the same drug under similar dosage conditions.

Evaluation of the Contribution of the Nasal Cavity and Gastrointestinal Tract to Drug Absorption Following Nasal Application to Rats

Drugs applied to the nose in in vivo physiologic condition undergo absorption from the nasal cavity and the gastrointestinal (GI) tract because drug solution in the nasal cavity, together with mucus layer, is cleared to pharynx and then to the GI tract by coordinated beat of the cilia on nasal epithelial cells. The purpose of this study was to develop evaluate the contribution of the nasal cavity and the GI tract to drug absorption following nasal application and to clarify the relation to the transepithelial permeability of the drug (the permeability to Caco-2 monolayer, P(Caco-2)). Male Wistar rats received intravenous, nasal, and oral drug administration and drug concentration-time profiles in plasma were determined. Fractional absorption after nasal application (Fn) and oral administration (Fpo) were calculated from the area under the curve following intravenous injection (AUCiv), nasal application (AUCn), and oral administration (AUCpo) as AUCn/AUCiv and AUCpo/AUCiv, respectively. Fractional absorption from the nasal cavity (F(NC)) and the GI tract (F(GI)) following nasal application was calculated as (Fn-Fpo)/(1-Fpo) and Fpo(1-F(NC)), respectively. The shape of the curve between F(NC) and P(Caco-2) was similar with the one observed in the case of oral bioavailability except the curve shifted right. It is noteworthy that the relation between F(GI) and P(Caco-2) showed a bell-shaped curve with peak at 10(-6) cm/s of P(Caco-2). Highly permeable drug is primarily absorbed through the nasal mucosa before it is cleared to the GI tract. With the decrease in P(Caco-2), the larger amount of the drug is cleared to the GI tract and absorption from the GI tract is increased. Poorly permeable drug, on the other hand, was absorbed neither from the nasal was nor the GI tract. These findings suggest that the primary absorption site of drug after nasal application is decided by mucociliary clearance and absorption through the nasal mucosa.

Trends in muco-adhesive analysis

The last two decades has seen progress in the development of potential mucoadhesive carriers for assisting with the oral and nasal administration of drugs based around the polysaccharide chitosan. This progress has been underpinned by the development of molecular assays for mucoadhesiveness focusing on the mucin component of mucus. We review the developments based around molecular or biophysical analyses and consider how the issue of product stability is now being addressed. Although the targets are pharmaceutical, the technology could be extended to the encapsulation and release of nutrients.

In vitro evaluation of thiomer microparticles for nasal drug delivery

The purpose of the present study was to compare two preparation methods concerning the development of a thiomer (polycarbophil-cysteine; PCP-Cys)-based microparticidate delivery system for nasal drug administration. Microparticles were prepared either by emulsification solvent evaporation technique or via mechanical micromotion. Resulting microparticles were characterized and compared concerning their inherent properties and the permeation enhancing effect of PCP-Cys in combination with the permeation mediator glutathione (GSH) was investigated on freshly excised bovine nasal mucosa. Additionally, the effect of PCP-Cys on the ciliary beat frequency (CUP) of human nasal epithelial cells was evaluated in vitro. Results demonstrated that microparticles of both preparation types were mainly of spherical structure displaying particle diameter up to 100 pm. Particles prepared by mechanical micronization showed a comparatively higher drug load compared to those produced via the emulsification solvent evaporation technique. In addition, controlled drug release of the incorporated model compounds sodium fluorescein (NaFlu) and FITC-dextran (FD 4) was achieved from these particles. The mucosal transport oJ'NaFlu and FD 4 was increased 1.70-fold and 2.64- fold, respectively, in the presence of the PCP-Cys/GSH system. Furthermore, no cilioto.xic effect could be observed for tliiolated polycarbophil. Due to these results polycarbophil-cysteine-based microparticles prepared either way seem to be a safe and promising tool in the field of nasal drug delivery.

S‐ketamine and s‐norketamine plasma concentrations after nasal and i.v. administration in anesthetized children

It has been suggested that nasal administration of s-ketamine may be used to improve sedation or premedication in combination with nasal midazolam in pediatric patients. In this study we measured and compared plasma concentrations of s-ketamine and its main metabolite s-norketamine after nasal and i.v. administration in preschool children. During sevoflurane anaesthesia, 20 children, aged 1-7 years, weight 11-25 kg, received s-ketamine 2 mg x kg(-1) either intranasally (Group IN, n = 10), or i.v. (Group IV, n = 10). Six venous blood samples were obtained up to 60 min after drug administration for measurement of s-ketamine and s-norketamine plasma concentrations. Plasma concentrations [mean +/- sd] of s-ketamine in group IN peaked at 355 +/- 172 ng x ml(-1) within 18 +/- 13 min vs. 1860 +/- 883 ng x ml(-1) within 3 +/- 1 min in group IV (P < 0.01). Plasma concentrations of s-norketamine in group IN peaked at 90 +/- 128 ng x ml(-1) within 50 +/- 11 min vs. 429 +/- 277 ng x ml(-1) within 40 +/- 16 min in group IV (P < 0.01). One child in group IN experienced rapid and high level s-ketamine absorption with a peak plasma concentration of 732 ng x ml(-1) after 2 min, which decreased to 274 ng x ml(-1) after 60 min. Systolic blood pressure and heart rate remained unaltered in both study groups after s-ketamine administration. Nasal administration of s-ketamine 2 mg x kg(-1) results in a wide spread of plasma concentrations and absorption times. Rapid and high level drug absorption after nasal drug administration is possible. The use of a pulse oximeter and continuous observation after nasal administration of s-ketamine for pediatric premedication is recommended.