Nasal delivery of fentanyl

Clinical and pharmacokinetics overview of intranasal administration of fentanyl

Due to the presence of large surfaces and high blood supply, drug delivery through the nasal route of administration is the appropriate route to administrate drugs with rapid onsets of action. Bypassing first-pass metabolism can increase drug bioavailability. The physicochemical properties of fentanyl led to a need to develop formulations for delivery by multiple routes. Several approved inter-nasal fentanyl products in Europe and the USA have been used in prehospital and emergency departments to treat chronic cancer pain and used to treat severe acute abdominal and flank pain. Analgesia durations and onsets were not significantly different between intranasal and intravenous fentanyl in patients with cancer breakthrough pain and were well-tolerated in the long term. Intranasal Fentanyl (INF) at a 50 μg/ml concentration decreased renal colic pain to the lowest level in 30 min. Possible adverse effects specific to INF are epistaxis, nasal wall ulcer, rhinorrhea, throat irritation, dysgeusia, nausea, and vomiting. However, there is limited available literature about the serious adverse effects of INF in adults and children. Intranasal Fentanyl Spray (INFS) results in significantly higher plasma concentrations and has a lower Tmax than oral transmucosal formulation, and the bioavailability of fentanyl in intranasal formulations is very high (89 %), particularly in pectin-containing formulations such as PecFent and Lazanda.

Pharmacokinetic Characterisation and Comparison of Bioavailability of Intranasal Fentanyl, Transmucosal, and Intravenous Administration through a Three-Way Crossover Study in 24 Healthy Volunteers

Background

For more than 60 years, the synthetic opioid fentanyl has been widely used in anaesthesia and analgesia. While the intravenous formulation is primarily used for general anaesthesia and intensive care settings, the drug's high lipophilic properties also allow various noninvasive routes of administration. Published data suggest that intranasal administration is also attractive for use as intranasal patient-controlled analgesia (PCA). A newly developed intranasal fentanyl formulation containing 47 μg fentanyl, intravenous fentanyl, and oral transmucosal fentanyl citrate were characterised, and bioavailability was compared to assess the suitability of the intranasal formulation for an intranasal PCA product.

Methods

27 healthy volunteers were enrolled in a single-centre, open-label, randomised (order of treatments), single-dose study in a three-period crossover design. The pharmacokinetics of one intranasal puff of fentanyl formulation (47 μg, 140 mL per puff), one short intravenous infusion of 50 μg fentanyl, and one lozenge with an integrated applicator (200 μg fentanyl) were studied, and bioavailability was calculated. Blood samples were collected over 12 hours, and plasma concentrations of fentanyl were determined by HPLC with MS/MS detection.

Results

24 volunteers completed the study. The geometric mean of AUC_0-tlast was the highest with oral transmucosal administration (1106 h ∗ pg/ml, CV% = 32.86), followed by intravenous (672 h ∗ pg/ml, CV% = 32.18) and intranasal administration (515 h ∗ pg/ml, CV% = 30.10). C _max was 886 pg/ml (CV% = 59.38) for intravenous, 338 pg/ml (CV% = 45.61) for intranasal, and 310 pg/ml (CV% = 29.58) for oral transmucosal administration. t _max was shortest for intravenous administration (0.06 h, SD = 0.056), followed by intranasal (0.21 h, SD = 0.078) and oral transmucosal administration (1.20 h, SD = 0.763). Dose-adjusted absolute bioavailability was determined to be 74.70% for the intranasal formulation and 41.25% for the oral transmucosal product. In total, 38 adverse events (AEs) occurred. Fourteen AEs were potentially related to the investigational items. No serious AE occurred.

Conclusion

Pharmacokinetic parameters and bioavailability of the investigated intranasal fentanyl indicated suitability for its intended use as an intranasal PCA option.

Innovative sprayable in situ gelling fluticasone suspension: Development and optimization of nasal deposition

The aim of this study was to develop an innovative in situ gelling suspension for effective nasal delivery of fluticasone. Pectin, gellan gum and sodium hyaluronate were used as gelling/thickening agents, and Tween 80 as a suspending agent. The influence of the formulation and/or administration parameters on formulation sprayability and nasal deposition was explored with an appropriate experimental design with the range for parameters in the design obtained from previous research and domain knowledge. All formulations exhibited appropriate sprayability and instant gelation upon mixing with simulated nasal fluid exhibiting weak gel properties convenient for nasal delivery. Targeted turbinate deposition depended on administration and formulation parameters, including their interactions. Decrease in the administration angle from horizontal plane, increase in inspiratory flow and presence of sodium hyaluronate significantly increased deposition in turbinate region. Parameters in interactions included concentration of polymers, surfactant and fluticasone, as well as administration angle. Selected formulations with high turbinate deposition exhibited significant increase in viscosity upon gelation, showing potential to prolong the drug retention at the nasal mucosa. The highest effect on the gel viscosity, strength and fluticasone release profile was observed for gellan gum, thus recognised as crucial parameter for the optimisation of overall therapeutic effect.

The Use of Intranasal Fentanyl for the Palliation of Incident Dyspnea in Advanced Congestive Heart Failure: A Pilot Study

Background:

Dyspnea is distressing in palliative patients with end-stage heart failure and many are hospitalized to optimize this symptom. We hoped to conduct a pilot study to determine whether the administration of intranasal fentanyl would decrease activity-induced dyspnea in this patient population.

Methods:

Patients performed two 6-minute walk tests with and without the administration of 50 μg of intranasal fentanyl. Vital signs were recorded before and after each walk, as were participant reported dyspnea and adverse events scores.

Results:

Twenty-four patients were screened, 13 were deemed eligible, and 6 completed the study. Dyspnea scores changed from a mean of 6.00 immediately after the walk without fentanyl to a mean of 3.83 after the walk with fentanyl ( P = .048). Mean respiratory rate decreased from 21.0 to 18.7 ( P = .034) breaths per minute and was considered a favorable outcome by the participants. Distance walked did not significantly increase with the fentanyl pretreatment (136.0-144.2 m; P = .283), although the participants reported feeling better while walking a similar distance.

Conclusions:

In this pilot study, the preadministration of intranasal fentanyl prior to activity in palliative, end-stage hospitalized heart failure patients, safely reduced tachypnea, and the feeling of shortness of breath. This approach may help palliate advanced heart failure patients by alleviating symptoms brought on by exertional activities.

Lipid/alginate nanoparticle-loaded in situ gelling system tailored for dexamethasone nasal delivery

In this study, we suggest the development of nanoparticle loaded in situ gelling system suitable for corticosteroid nasal delivery. We propose lipid/alginate nanoparticles (size 252.3±2.4nm, polydispersity index 0.241, zeta-potential -31.7±1.0mV, dexamethasone (Dex) content 255±7μgml^-1) dispersed in pectin solution (5mgml^-1) that undergoes a sol-gel phase transition triggered by Ca²⁺ present in nasal mucosa. The viscoelasticity of gel obtained by mixing nanoparticle suspension in pectin continuous phase with simulated nasal fluid (1:1V/V) is characterised by a log-linear shear thinning viscosity behaviour. Observed viscosity corresponds to the range of viscosities of nasal mucus at physiological as well as under disease conditions. Nanoparticle-loaded gel was biocompatible with the selected epithelial cell model and, in comparison to dexamethasone solution, provided reduction in Dex release (t_50% 2.1h and 0.6h, respectively) and moderated transepithelial permeation in vitro (P_app 7.88±0.15 and 9.73±0.57×10^-6cms^-1, respectively). In conclusion, this study showed the potential of the proposed system to provide local therapeutic effect upon administration of a lower corticosteroid dose and minimize the possibility for adverse effects as it can be easily sprayed as solution and delivered beyond nasal valve, ensure prolonged contact time with nasal mucosa upon gelation, and moderate corticosteroid release and permeation.