The assessment of topical nasal drug distribution

Deviated nasal septum hinders intranasal sprays: a computer simulation study

BACKGROUND

This study investigates how deviated nasal septum affects the quantity and distribution of spray particles, and examines the effects of inspiratory airflow and head position on particle transport.

METHODS

Deposition of spray particles was analysed using a three-dimensional computational fluid dynamics model created from a computed tomography scan of a human nose with leftward septal deviation and a right inferior turbinate hypertrophy. Five simulations were conducted using FluentTM software, with particle sizes ranging from 20-110 μm, a spray speed of 3 m/s, plume angle of 68(deg), and with steady state inspiratory airflow either present (15.7 L/min) or absent at varying head positions.

RESULTS

With inspiratory airflow present, posterior deposition on the obstructed side was approximately four times less than the contralateral side, regardless of head position, and was statistically significant. When airflow was absent, predicted deposition beyond the nasal valve on the left and right sides were between 16% and 69% lower and positively influenced by a dependent head position.

CONCLUSION

Simulations predicted that septal deviation significantly diminished drug delivery on the obstructed side. Furthermore, increased particle penetration was associated with presence of nasal airflow. Head position is an important factor in particle deposition patterns when inspiratory airflow is absent.

Nasal drug delivery devices: characteristics and performance in a clinical perspective-a review

Nasal delivery is the logical choice for topical treatment of local diseases in the nose and paranasal sinuses such as allergic and non-allergic rhinitis and sinusitis. The nose is also considered an attractive route for needle-free vaccination and for systemic drug delivery, especially when rapid absorption and effect are desired. In addition, nasal delivery may help address issues related to poor bioavailability, slow absorption, drug degradation, and adverse events in the gastrointestinal tract and avoids the first-pass metabolism in the liver. However, when considering nasal delivery devices and mechanisms, it is important to keep in mind that the prime purpose of the nasal airway is to protect the delicate lungs from hazardous exposures, not to serve as a delivery route for drugs and vaccines. The narrow nasal valve and the complex convoluted nasal geometry with its dynamic cyclic physiological changes provide efficient filtration and conditioning of the inspired air, enhance olfaction, and optimize gas exchange and fluid retention during exhalation. However, the potential hurdles these functional features impose on efficient nasal drug delivery are often ignored. With this background, the advantages and limitations of existing and emerging nasal delivery devices and dispersion technologies are reviewed with focus on their clinical performance. The role and limitations of the in vitro testing in the FDA guidance for nasal spray pumps and pressurized aerosols (pressurized metered-dose inhalers) with local action are discussed. Moreover, the predictive value and clinical utility of nasal cast studies and computer simulations of nasal airflow and deposition with computer fluid dynamics software are briefly discussed. New and emerging delivery technologies and devices with emphasis on Bi-Directional™ delivery, a novel concept for nasal delivery that can be adapted to a variety of dispersion technologies, are described in more depth.

Topical Drug Delivery for Chronic Rhinosinusitis

Chronic rhinosinusitis is a multifactorial disorder that may be heterogeneous in presentation and clinical course. While the introduction of endoscopic sinus surgery revolutionized surgical management and has led to significantly improved patient outcomes, medical therapy remains the foundation of long-term care of chronic rhinosinusitis, particularly in surgically recalcitrant cases. A variety of devices and pharmaceutical agents have been developed to apply topical medical therapy to the sinuses, taking advantage of the access provided by endoscopic surgery. The goal of topical therapy is to address the inflammation, infection, and mucociliary dysfunction that underlies the disease. Major factors that impact success include the patient's sinus anatomy and the dynamics of the delivery device. Despite a growing number of topical treatment options, the evidence-based literature to support their use is limited. In this article, we comprehensively review current delivery methods and the available topical agents. We also discuss biotechnological advances that promise enhanced delivery in the future, and evolving pharmacotherapeutical compounds that may be added to rhinologist's armamentarium. A complete understand of topical drug delivery is increasingly essential to the management of chronic rhinosinusitis when traditional forms of medical therapy and surgery have failed.

Computed intranasal spray penetration: comparisons before and after nasal surgery

BACKGROUND

Quantitative methods for comparing intranasal drug delivery efficiencies pre- and postoperatively have not been fully utilized. The objective of this study is to use computational fluid dynamics techniques to evaluate aqueous nasal spray penetration efficiencies before and after surgical correction of intranasal anatomic deformities.

METHODS

Ten three-dimensional models of the nasal cavities were created from pre- and postoperative computed tomography scans in 5 subjects. Spray simulations were conducted using a particle size distribution ranging from 10 μm to 110 μm, a spray speed of 3 m/second, plume angle of 68 degrees, and with steady state, resting inspiratory airflow present. Two different nozzle positions were compared. Statistical analysis was conducted using Student t test for matched pairs.

RESULTS

On the obstructed side, posterior particle deposition after surgery increased by 118% and was statistically significant (p = 0.036), while anterior particle deposition decreased by 13% and was also statistically significant (p = 0.020). The fraction of particles that bypassed the airways either pre- or postoperatively was less than 5%. Posterior particle deposition differences between obstructed and contralateral sides of the airways were 113% and 30% for pre- and postsurgery, respectively. Results showed that nozzle positions can influence spray delivery.

CONCLUSION

Simulations predicted that surgical correction of nasal anatomic deformities can improve spray penetration to areas where medications can have greater effect. Particle deposition patterns between both sides of the airways are more evenly distributed after surgery. These findings suggest that correcting anatomic deformities may improve intranasal medication delivery. For enhanced particle penetration, patients with nasal deformities may explore different nozzle positions.

Sonic aerosol therapy to target maxillary sinuses

AIM

Intranasal aerosol administration of drugs is widely used by ENT specialists. Although clinical evidence is still lacking, intranasal nebulization appears to be an interesting therapeutic option for local drug delivery, targeting anatomic sites beyond the nasal valve. The sonic nebulizer NL11SN associates a 100Hertz (Hz) sound to the aerosolization to improve deposition in the nasal/paranasal sinuses. The aim of the present study was: to evaluate in vivo the influence of associating a 100Hz sound on sinus ventilation and nasal and pulmonary aerosol deposition in normal volunteers, and; to quantify in vitro aerosol deposition in the maxillary sinuses in a plastinated head model.

MATERIAL AND METHODS

Scintigraphic analysis of (81m)Kr gas ventilation and of sonic aerosol ((99m)Tc-DTPA) deposition using the NL11SN was performed in vivo in seven healthy volunteers. In parallel, NL11SN gentamicin nebulization was performed, with or without associated 100Hz sound, in a plastinated human head model; the gross amount of gentamicin delivered to the paranasal sinuses was determined by fluorescence polarization immunoassay.

RESULTS

Associating the 100Hz sound to (81m)Kr gas ensured paranasal sinus ventilation in healthy volunteers. (99m)Tc-DTPA particles nebulized with the NL11SN were deposited predominantly in the nasal cavities (2/3, vs 1/3 in the lungs). In vitro, the use of NL11SN in sonic mode increased gentamicin deposition threefold in the plastinated model sinuses (P<0.002); the resulting antibiotic deposit would be sufficient to induce a local therapeutic effect.

CONCLUSION

The NL11SN nebulizer ensured preferential nasal cavity aerosol deposition and successfully targeted the maxillary sinuses.

Nasal gel and olfactory cleft

OBJECTIVE

To evaluate whether a nasal gel, administrated using a radial-hole inhaler, reaches the olfactory cleft and if a different administration method influences distribution.

MATERIAL AND METHOD

Sixteen healthy volunteers underwent a nasal endoscopy at 1 and 7minutes after the administration of a intranasal gel, with a different method in each fossa.

RESULTS

No dye deposition was identified at the olfactory cleft, middle turbinate or middle meatus. In all cases the gel was identified at the nasal vestibule. On the right side, the second most frequent dye identification area was the inferior turbinate, with a rate of 87% at the first minute and 75% at 7 minutes. It was followed by the septum (75 and 62%) and the inferior meatus (6.2 and 12.5%). On the left side, the second most frequent stained area was the septum (18.7 and 13.5%), followed by the inferior meatus (6.5 and 65%). No inferior turbinate staining was found in the left side. There was a significant difference in the deposition rate at the septum (P<.01) and inferior turbinate (P<.001), when both administration methods were compared.

CONCLUSIONS

No nasal gel, administrated using a radial-hole inhaler, was found at the olfactory cleft, middle turbinate or middle meatus. Gel distribution was located at the anterior and inferior portion of the nose, independent of the administration method used. Significantly different gel distribution rates were found at the septum and inferior turbinate when the 2 administration methods were compared.

Novel drug-delivery systems for patients with chronic rhinosinusitis

Chronic rhinosinusitis, one of the most common chronic medical complaints in the United States, seems to be increasing in incidence and prevalence, and has a significant impact on quality of life. Topical forms of medical therapy represent an attractive alternative for drug delivery to the nasal cavity and paranasal sinuses. Topical drug delivery has the advantage of directly acting on the site of inflammation, producing a higher concentration at the target site while avoiding systemic side effects. Although considerable research has been undertaken into improving nasal formulations in order to enhance absorption, little attention has so far been directed to upgrading the delivery devices. The aim of this review is to present current knowledge on the novel drug-delivery devices in use in the management of chronic rhinosinusitis patients, and to present the current available knowledge on topical drug penetration into the sinuses using various delivery devices. Additionally, methods used to enhance fluid sinus deposition are presented and the published clinical studies on the results of nebulized antibiotics in the treatment of chronic rhinosinusitis patients are discussed.

Nasal deposition and clearance in man: comparison of a bidirectional powder device and a traditional liquid spray pump

BACKGROUND

Delivery of powder formulations to the nose is an attractive alternative for many drugs and vaccines. This study compared the regional nasal deposition and clearance patterns of lactose powder delivered by the OptiNose powder device (Opt-Powder; OptiNose US Inc., Yardley, PA, USA) to that of liquid aerosol administered via a traditional hand-actuated liquid spray pump (Rexam SP270, Rexam Pharma, France).

METHODS

The study was an open-label, crossover design in seven healthy subjects (five females, two males). The regional nasal deposition and clearance patterns of the Opt-Powder device were compared to a traditional liquid spray pump by dynamic gamma camera imaging after administration of either (99m)Tc-labeled lactose powder or liquid (99m)Tc- diethelyne triamine pentaacetic acid-aerosol. The gamma camera images were scaled and aligned with sagittal magnetic resonance images to identify nasal regions. Possible deposition of radiolabeled material in the lungs following both methods of delivery was also evaluated.

RESULTS

Both powder and spray were distributed to all of the nasal regions. The Opt-Powder device, however, achieved significantly larger initial deposition in the upper and middle posterior regions of the nose than spray (upper posterior region; Opt-Powder 18.3% ± 11.5 vs. Spray 2.4% ± 1.8, p<0.02; sum of upper and middle posterior regions; Opt-Powder 53.5% ± 18.5 vs. Spray 15.7% ± 13.8, p<0.02). The summed initial deposition to the lower anterior and posterior regions for spray was three times higher compared to Opt-Powder (Opt-Powder 17.4% ± 24.5 vs. Spray 59.4% ± 18.2, p<0.04). OptiNose powder delivery resulted in more rapid overall nasal clearance. No lung deposition was observed.

CONCLUSIONS

The initial deposition following powder delivery was significantly larger in the ciliated mucosa of the upper and posterior nasal regions, whereas less was deposited in the lower regions. Overall nasal clearance of powder was slower initially, but due to retention in anterior nonciliated regions the overall nasal clearance after spray was slower.

Radiographic distribution of drops and sprays within the sinonasal cavities

BACKGROUND

Topical nasal sprays are commonly prescribed for sinonasal disease. Nasal drops applied in a head-down position are described alternatively to sprays. Multiple research methods have investigated the deposition pattern of intranasal medications, each with limitations. This pilot study analyzed the use of a conebeam computed tomography (CBCT) scanner to study deposition patterns of intranasal sprays and drops using radiopaque contrast solution.

METHODS

Nine volunteers participated in this two-trial study. In trial 1, participants instilled 3 sprays of contrast into each nostril. After 3 minutes a CBCT scan was performed. In trial 2, 3 drops of contrast were instilled into the participants' nostrils in the "vertex-to-floor" position. Again, after 3 minutes a CBCT scan was performed. Two otolaryngologists and a neuroradiologist reviewed the images and scored 21 sites within the sinonasal cavity for the presence of contrast.

RESULTS

Contrast was detected in the nasal vestibule and inferior nasal vault in nearly every trial with the spray and drops. Nasal spray was more diffusely distributed within the nasal cavity and was detected at a greater proportion on the floor of the nose, inferior meatus, anterior inferior nasal cavity, and nasopharynx. Neither spray nor drops were consistently detected in spaces superior to the middle turbinate.

CONCLUSION

Radiopaque contrast delivered by nasal spray and drops were detected by the CBCT scanner, with a significant difference at one subsite. Neither spray nor drops were detected in superior nasal spaces. The CBCT scan provides an alternative to conventional CT scans in future studies using this technique.

A feasibility study to evaluate a novel drug delivery technique through nasal/sinus mucosa using a biodegradable polymer in a guinea pig model

OBJECTIVE

Targeted topical pharmaceuticals have fewer side effects than systemic therapy and present an interesting option to treat chronic sinus disease. A simple, dependable, resorbable drug delivery mechanism has been elusive. The goal of this study is to examine the feasibility of a novel bioresorbable synthetic polymer for drug delivery in nose and sinuses.

STUDY DESIGN

Feasibility study.

SETTING

Animal study.

SUBJECTS AND METHODS

Polyurethane sponges soaked in either triamcinolone or gentamicin were placed in the ethmoid cavities of 14 guinea pigs via an external approach; 2 additional animals served as controls. Serum levels of each drug were assayed at intervals up to 21 days. Histopathological examination of the relevant sinonasal anatomy of each animal was performed after 21 days.

RESULTS

Serum levels of each drug were detectable between days 1 and 21. There were no significant differences in the histopathological examination of nasal mucosa in guinea pigs in which either drug was applied compared with control animals in which the bioabsorbable material was soaked in saline. The polyurethane sponge did not cause any foreign body reaction, granuloma, or polypoidal change to the sinus mucosa. Two animals developed a subclinical infection at the surgical site.

CONCLUSION

The targeted use of topical pharmaceuticals via a synthetic bioresorbable nasal sponge dressing in this guinea pig model demonstrated minimal systemic absorption and minimal histopathological changes. This technology is currently under investigation in human clinical trials.

Deposition of aerosols delivered by nasal route with jet and mesh nebulizers

PURPOSE

To quantify the amount of aerosol deposited in different parts of the airways with a commercially available nasal sonic jet nebulizer (NJN) using a sound effect, and to compare its performance with a new nasal mesh nebulizer (NMN).

METHODS

Seven healthy non-smoking male volunteers aged 21-36 years with a mean weight of 77±10 kg were included in this single-center study. Both nebulizer systems were loaded with (99m)Tc-DTPA and scintigraphies were performed with a gamma camera. Particle size distribution of the aerosols produced by the two nebulizer systems was measured.

RESULTS

There was no statistical difference between the two nebulizers in terms of fraction of particles smaller than 5 μm (44±4% vs 45±2%) (p>0.9). Aerosol deposition in the nasal region was 73±10% (% of aerosol deposited in airways) with the NJN, and 99±3% with the NMN (p=0.01). Total nasal deposition was 9.6±1.9% of the nebulizer charge with the NJN and 28.4±8.9% with the NMN (p=0.01). 0.5±0.3% of the nebulizer charge was deposited in the maxillary sinuses with the NJN, compared to 2.2±1.6% with the NMN (p=0.01).

CONCLUSION

Although the two nebulizers had the same particle size, NMN significantly improved aerosol deposition in nasal cavity and prevents deposition into the lungs.

Automated actuation of nasal spray products: determination and comparison of adult and pediatric settings

OBJECTIVE

To determine and compare patient-relevant settings for automated nasal spray actuation stations from adult and pediatric hand data.

METHODS

Twenty adults and 20 pediatric participants were asked to spray Flonase(®) Nasal Spray six times in a Hand Actuation Monitor, which records force and displacement data in 5-ms increments. Settings for force- and velocity-controlled actuation stations were determined from the data using a predefined set of calculations.

RESULTS

For force-controlled settings, hand spraying by children resulted in lower actuation forces, and longer force rise, hold and fall times. Pediatric velocity-controlled actuator settings were lower for travel, compression velocity, and release velocity compared with adults. The pediatric spray weight recorded during hand spraying was significantly lower than the spray weight generated by adult participants. Adult participants were able to generate full sprays with each attempt, whereas 11 out of 120 actuations performed by pediatric participants resulted in partial and 'no spray' events. No differences in spray weight were detected in participants who chose to actuate the nasal spray using both hands.

CONCLUSIONS

A predefined set of calculations was used to determine patient-relevant settings from force and displacement hand data for force- and velocity-controlled automated actuation stations. This study determined and quantified, for the first time, the differences in hand spraying between adults and children.

Impact of baseline nasal polyp size and previous surgery on efficacy of fluticasone delivered with a novel device: a subgroup analysis

BACKGROUND

Little information exists on the impact of baseline polyp size and previous nasal surgery on the efficacy of intranasal steroids. This study was designed to investigate whether baseline polyp size and previous nasal surgery influence the efficacy of an intranasal steroid delivered with a novel device.

METHODS

A post hoc analysis of recently published results with intranasal administration using a novel bidirectional delivery device containing fluticasone propionate (Opt-FP) was performed in 109 patients with mild-to-moderate bilateral polyposis. Patients were allocated to subgroups based on summed polyp score at baseline (2, 3, or 4) and on their history of previous sinus surgery.

RESULTS

A highly significant and progressive reduction in summed polyp size was observed for Opt-FP versus placebo in all three polyp size subgroups (p < 0.001). A greater relative reduction in polyp size (p < 0.05) and an increase in peak nasal inspiratory flow (p < 0.001) were observed for Opt-FP at 12 weeks in the 28 patients with a baseline summed score of 3 and 4 compared with the 27 with a summed score of 2. Nevertheless, in patients with small polyps at baseline, the polyps were completely resolved on both sides in 7 of 27 patients. Previous sinus surgery had no impact on efficacy.

CONCLUSION

The highly significant progressive treatment effect of Opt-FP was observed regardless of baseline polyps score. Coupled with the complete removal of polyps in many patients with small polyps, this suggests that improved deposition to target sites achieved with the bidirectional delivery device may translate into true clinical benefits and reduced need for surgery.

Local drug delivery

Topical drug delivery for sinonasal disorders is influenced by a variety of factors. Macroscopically (or anatomically), the ability of the drug to reach the appropriate region of the paranasal system is paramount. Delivery techniques, surgical state of the sinus cavity, delivery device, and fluid dynamics (volume, pressure, position) have a significant impact on the delivery of topical therapies to the sinus mucosa. Once topical therapeutics actually reach the desired site, factors within the local microenvironment heavily influence local drug delivery. The presence and composition of the mucus blanket, mucociliary clearance, direct mucin-drug binding, and the permeability of pharmaceutical compounds will all impact drug delivery. In addition, the general therapeutic goal of topical management may lie between the potentially competing actions of mechanical lavage and pharmaceutical intervention. Techniques for the mechanical removal of mucus, antigen, and inflammatory products may not be the most efficient approach for pharmaceutical delivery. This article reviews the evolving concepts in local drug therapy, both for the factors that influence anatomic distribution within the sinonasal system and those that affect mucosal absorption.

Rapid absorption of sumatriptan powder and effects on glyceryl trinitrate model of headache following intranasal delivery using a novel bi-directional device

Objectives

The aim was to investigate the pharmacokinetics of intranasal sumatriptan (administered using a novel bi-directional powder delivery device) and study its effects on quantitative electroencephalography in patients with migraine. The safety profiles of the two formulations were also compared.

Methods

The pharmacokinetics of intranasal sumatriptan (10 mg and 20 mg) administered using a novel breath-actuated bi-directional powder delivery device were compared with subcutaneous sumatriptan (6 mg), along with an investigation of their effects on the electroencephalogram (EEG) following glyceryl trinitrate (GTN) challenge in 12 patients with migraine using a randomized, three-way cross-over design.

Key findings

Following intranasal delivery, median tmax was 20 min with both doses compared with 10 min after the subcutaneous dose. Mean ± SD values for Cmax were 96 ± 25, 11 ± 7 and 16 ± 6 ng/ml for subcutaneous, intranasal 10 mg and intranasal 20 mg formulations, respectively. Values for area under the curve were also lower with the intranasal doses. Intranasal and subcutaneous sumatriptan induced similar EEG changes characterized by reduced theta-power and increased beta-power. The majority of study participants were free of pain according to the headache severity score with all treatments from 15 min through to 8 h post-dose. All treatments were well tolerated and there were no reports of bitter aftertaste after intranasal delivery. Sumatriptan was rapidly absorbed after intranasal administration using the new device. Using the GTN challenge, sumatriptan powder delivered intranasally at a dose of 20 mg by the new device had effects similar to those of subcutaneous sumatriptan on EEG and reported headache pain, despite much lower systemic exposure.

Conclusions

Administration of sumatriptan intranasally at doses of 10 mg and 20 mg by the breath actuated bi-directional powder delivery device results in rapid absorption. Delivery to target sites beyond the nasal valve induced a similar EEG profile to subcutaneous sumatriptan 6 mg and prevented migraine attacks in patients following GTN challenge. Intranasal administration of sumatriptan powder with the breath actuated bi-directional powder delivery device was well tolerated.

The effect of functional endoscopic sinus surgery on nasal spray distribution to the middle meatus in patients with rhinosinusitis

BACKGROUND

Because the principle behind functional endoscopic sinus surgery (FESS) recognizes the middle meatus as essential for the control of the disease, the effect of the operation in the distribution of drugs in the same area should be of similar importance. This study was designed to clarify whether nasal drug delivery is improved in patients after FESS. The study involved a prospective assessment within subject comparison. The subjects were 20 adult (>18 years old) patients on the waiting list for FESS. It was conducted within two teaching hospitals in the East of Scotland.

METHODS

A novel method was used, positioning a neurosurgical patty in the middle meatus and assessing blue dye nasal spray absorption on a 4-point scale.

RESULTS

A significant improvement was observed in the distribution of the indicator in the middle meatus postoperatively. Seventy percent of the patients showed improvement in the drug distribution after FESS. The median result for absorption score was 2 preoperatively (<50%) and 3 postoperatively (>50%). The difference was statistically significant (p<0.001).

CONCLUSION

The distribution of nasal drugs is improved in the middle meatus after FESS. This can have important clinical applications that can benefit patients in otolaryngology as well as other disciplines.

A new method for scintigraphic quantification of deposition and clearance in anatomical regions of the human nose

OBJECTIVES

To develop methods for absolute quantification of the deposition of 99mTc-labeled aerosols and powders in well-defined anatomical regions of the nose, and to enable accurate comparisons of different nasal administration techniques in the same individual.

METHODS

The volunteer was seated and positioned relative to the scintillation camera field of view by means of a fixation frame. After nasal administration, a dynamic series of images was acquired for 32 min with a lateral direction of view. The images were corrected for photon attenuation by the use of a lateral transmission image acquired before the delivery of aerosols or powders. Marker images, obtained with a line source fixed to a balloon and kept for a short while against the palate as well as with a point source held on anatomical landmarks, were used to co-register the scintigraphic images to sagital sections through a three-dimensional magnetic resonance (MR)-image series. The MR set was used to define the inner nose contour and the nasal regions used for quantification.

RESULT

Attenuation correction factors ranged from 1.1 to 1.7 in different parts of the nasal cavity. Alignment of the markers on the teeth and palate with the sagital MR images could be reproduced with accuracies of 1.2 and 1.7 mm, respectively.

CONCLUSION

The new method provides reliable quantification of the deposition in anatomic regions that can be defined in MR images. Accurate co-registration and quantification are essential when comparing distribution and clearance patterns for different administration techniques.

The ABCs of asthma control

The new asthma guidelines have introduced impairment and risk assessments into the management of asthma. Impairment assessment is based on symptom frequency and pulmonary function, whereas risk assessment is based on exacerbation frequency and severity. These 2 measures determine the initial severity of asthma in the untreated patient as well as the degree of control in asthma once treatment has been initiated. The focus on asthma control is important because the attainment of control correlates with a better quality of life and reduction in health care use. We describe 4 easy steps to achieving asthma control in the ambulatory practice setting: (1) a standardized assessment of asthma symptoms using a 5-question assessment tool called the Asthma Control Test, (2) a simple mnemonic that provides a systematic review of the comorbidities and clinical variables that contribute to uncontrolled asthma, (3) directed patient education, and (4) a schedule for ongoing care. Most if not all patients can achieve good control of their asthma with optimal care through an active partnership with their health care professionals.

Effect of topical ciprofloxacin/dexamethasone or dexamethasone alone on acute Streptococcus pneumoniae rhinosinusitis in mice

OBJECTIVE: To test whether intranasal ciprofloxacin/dexamethasone or dexamethasone alone affects the course of acute bacterial rhinosinusitis in mice.

STUDY DESIGN: We performed a randomized, double-blind, parallel, placebo-controlled study in mice.

SUBJECTS AND METHODS: Three groups of 10 C57B1/6 mice were infected with Streptococcus pneumoniae, and then 1 day later randomized to treatment with placebo, ciprofloxacin plus dexamethasone, or dexamethasone. The mice were killed 3 or 10 days after treatment was begun.

RESULTS: The placebo-treated mice became infected and developed an inflammatory cell infiltration in their sinuses. None of the treatments significantly affected the course of the illness.

CONCLUSION: The lack of topical, intranasal efficacy of ciprofloxacin and dexamethasone could be attributed to subpotent dosage, rapid nasal clearance, or inability of the drops to reach the site of infection. Treatment with dexamethasone neither improved nor worsened the bacterial infection.

The influence of spray properties on intranasal deposition

While numerous devices, formulations, and spray characteristics have been shown to influence nasal deposition efficiency, few studies have attempted to identify which of these interacting factors plays the greatest role in nasal spray deposition. The deposition patterns of solutions with a wide range of surface tensions and viscosities were measured using an MRI-derived nasal cavity replica. The resulting spray plumes had angles between 29 degrees and 80 degrees and contained droplet sizes (D(v50)) from 37-157 microm. Each formulation contained rhodamine 590 as a fluorescent marker for detection. Administration angles of 30 degrees , 40 degrees , or 50 degrees above horizontal were tested to investigate the role of user technique on nasal deposition. The amount of spray deposited within specific regions of the nasal cavity was determined by disassembling the replica and measuring the amount of rhodamine retained in each section. Most of the spray droplets were deposited onto the anterior region of the model, but sprays with small plume angles were capable of reaching the turbinate region with deposition efficiencies approaching 90%. Minimal dependence on droplet size, viscosity, or device was observed. Changes in inspiratory flow rate (0-60 L/min) had no significant effect on turbinate deposition efficiency. Both plume angle and administration angle were found to be important factors in determining deposition efficiency. For administration angles of 40 degrees or 50 degrees , maximal turbinate deposition efficiency (30-50%) occurred with plume angles of 55-65 degrees , whereas a 30 degrees administration angle gave an approximately 75% deposition efficiency for similar plume angles. Deposition efficiencies of approximately 90% could be achieved with plume angles <30 degrees using 30 degrees administration angles. Both the plume angle and administration angle are critical factors in determining deposition efficiency, while many other spray parameters, including particle size, have relatively minor influences on deposition within the nasal cavity.

Intranasal corticosteroids: the development of a drug delivery device for fluticasone furoate as a potential step toward improved compliance

Devices for the aqueous delivery of intranasal corticosteroids to patients with allergic rhinitis have been available since 1984, so there is a need for new devices to be developed to provide ease of use, efficacy and safety. A novel drug delivery system has been developed for fluticasone furoate (FF; GlaxoSmithKline): a new enhanced-affinity glucocorticoid with a scent-free formulation. The FF system was developed, giving attention to patients' unmet needs, in order to promote acceptance and compliance. It demonstrates a number of key features including its ergonomic design, side-actuation system and short delivery nozzle. Exploiting issues with present devices highlighted the need for the FF system. This review reports data from key studies and surveys conducted by GlaxoSmithKline during development, to determine ease of use and acceptance of the FF system. Findings suggest that the FF system should aid in improving attitudes to the use of intranasal corticosteroids amongst physicians and patients.

Influence of anatomy and head position on intranasal drug deposition

The objective of this study was to determine the influence of individual anatomical differences on intranasal drug deposition. The data of a comparison of seven different administration techniques in ten healthy volunteers was used in this single-blind crossover pilot study. After intranasal administration of a dyed test formulation, endoscopic video imaging was done on seven non-sequential days. The deposition pattern per individual around the head of the middle turbinate was analyzed for each technique and correlated with the individual anatomy. Decreased deposition of dyed test formulation in the target area around the head of the middle turbinate was observed in the presence of minor septal deviations, narrow nasal valve areas, or inferior turbinate hypertrophy; a lateral head position helps to bypass a minor septal deviation. Although results are preliminary, we conclude that anatomy and head position are important factors in the deposition of topical nasal drugs and may be the key to improving individual local nasal (steroid) treatment.

Oral spray immunization may be an alternative to intranasal vaccine delivery to induce systemic antibodies but not nasal mucosal or cellular immunity

Sixty-five healthy adult volunteers were immunized four times at 1-week intervals with an inactivated whole-virus influenza vaccine based on the strain A/New Caledonia/20/99 (H1N1) without adjuvant. The vaccine was administered as nasal spray with a newly developed device to secure intranasal delivery (OptiMist, OptiNose AS, Oslo, Norway), as regular nasal spray, nasal drops or as an oral spray. Significant IgA-antibody responses in nasal secretions were induced in volunteers immunized intranasally but not after oral spray immunization. In saliva, IgA antibodies were only marginally amplified even after oral spray immunizations. At least 73% of the volunteers belonging to any group of vaccine delivery reached serum haemagglutination inhibition titres of 40 or higher, considered protective against influenza, after only two vaccine doses. Those who had the vaccine delivered intranasally also showed evidence from in vitro secretion of granzyme B that cytotoxic T cells had been stimulated. Although immunization with the breath-actuated OptiMist device and nasal drops were superior with respect to both mucosal and systemic immune responses, oral spray immunization might still be considered for studies of mucosal adjuvants that are not yet acceptable for intranasal use.