The influence of recrystallized caffeine on water-swellable polymethacrylate mucoadhesive buccal films

The aim of this work was to investigate the influence of particles on the properties of polymethacrylate films intended for buccal delivery. A solvent casting method was used with Eudragit RS and RL (ERS and ERL, respectively) as film-forming rate-controlling polymers, with caffeine as a water-soluble model drug. The physicochemical properties of the model films for a series of formulations with increasing concentrations of caffeine were determined in terms of morphology, mechanical and mucoadhesive properties, drug content uniformity, and drug release and associated kinetics. Typically regarded as non-mucoadhesive polymers, ERS and mainly ERL, were found to be good mucoadhesives, with ERL01 exhibiting a work of mucoadhesion (WoA) of 118.9 μJ, which was about five to six times higher than that observed for commonly used mucoadhesives such as Carbopol(®) 974P (C974P, 23.9 μJ) and polycarbophil (PCP, 17.4 μJ). The mucoadhesive force for ERL01 was found to be significantly lower yet comparable to C974P and PCP films (211.1 vs. 329.7 and 301.1 mN, respectively). Inspection of cross-sections of the films indicated that increasing the concentration of caffeine was correlated with the appearance of recrystallized agglomerates. In conclusion, caffeine agglomerates had detrimental effects in terms of mucoadhesion, mechanical properties, uniformity, and drug release at large particle sizes. ERL series of films exhibited very rapid release of caffeine while ERS series showed controlled release. Analysis of release profiles revealed that kinetics changed from a diffusion controlled to a first-order release mechanism.

Design expert supported mathematical optimization and predictability study of buccoadhesive pharmaceutical wafers of Loratadine

OBJECTIVE

The objective of this work encompasses the application of the response surface approach in the development of buccoadhesive pharmaceutical wafers of Loratadine (LOR).

METHODS

Experiments were performed according to a 3(2) factorial design to evaluate the effects of buccoadhesive polymer, sodium alginate (A), and lactose monohydrate as ingredient, of hydrophilic matrix former (B) on the bioadhesive force, disintegration time, percent (%) swelling index, and time taken for 70% drug release (t(70%)). The effect of the two independent variables on the response variables was studied by response surface plots and contour plots generated by the Design-Expert software. The desirability function was used to optimize the response variables.

RESULTS

The compatibility between LOR and the wafer excipients was confirmed by differential scanning calorimetry, FTIR spectroscopy, and X-ray diffraction (XRD) analysis. Bioadhesion force, measured with TAXT2i texture analyzer, showed that the wafers had a good bioadhesive property which could be advantageous for retaining the drug into the buccal cavity.

CONCLUSION

The observed responses taken were in agreement with the experimental values, and Loratadine wafers were produced with less experimental trials, and a patient compliant product was achieved with the concept of formulation by design.

Effect of submucosal injection of dexamethasone on postoperative discomfort after third molar surgery: a prospective study

AIM

To evaluate the relative ability of 4 mg dose of intraoperative dexamethasone, administered submucosally, to reduce the postoperative discomfort after third molar surgery.

MATERIALS AND METHODS

A total of 100 patients requiring surgical removal of a single mandibular third molar were included. The experimental group (50) received dexamethasone 4 mg as submucosal injection and control group (50) received no drugs. The maximum interincisal distance and facial contours were measured at baseline and at postsurgery days 2 and 7. The measurement of pain was done using visual analog scale (VAS).

RESULTS

None of the patients developed wound infection or any serious postoperative complications. Postoperative edema tended to be less severe on the second postoperative day in the experimental group and the result was statistically significant. There were no significant differences in the reduction of pain and trismus between the two groups studied.

CONCLUSION

Submucosal administration of dexamethasone sodium phosphate (4 mg) results in reduction of postoperative edema, comparable with or greater than other routes of administration. Presumably, a higher effective drug concentration at the site of injury without loss due to distribution to other compartments may be achieved, and the submucosal route is convenient for both the surgeon and the patient.

CLINICAL SIGNIFICANCE

Submucosal route of administration of dexamethasone (4 mg) is effective in reducing postoperative discomfort after third molar surgeries.

Bioavailability and Metabolism of Prochlorperazine Administered via the Buccal and Oral Delivery Route

Prochlorperazine has been accepted as an effective antiemetic for more than 50 years; however, its therapeutic success has been limited by its low and variable absorption and high first-pass metabolism. A buccal dosage form of prochlorperazine has been developed. This article discusses 2 clinical studies conducted to characterize the single-dose and multiple-dose pharmacokinetics of prochlorperazine and its metabolites after buccal administration. The results of these studies demonstrate that buccal administration of prochlorperazine produces plasma concentrations more than twice as high as an oral tablet, with less than half the variability. In addition to the metabolites, N-desmethyl prochlorperazine and prochlorperazine sulfoxide, 2 new metabolites, prochlorperazine 7-hydroxide and prochlorperazine sulfoxide 4'-N-oxide, were identified and quantitated. Exposure to metabolites after the buccal prochlorperazine formulation was approximately half that observed after the oral tablet. Buccal administration of prochlorperazine, twice daily, should enhance the therapeutic role of prochlorperazine in preventing and treating nausea and vomiting.

[Management of breakthrough cancer pain]

Breakthrough cancer pain has been defined as a transitory increase in pain intensity that occurs despite relatively stable and adequately controlled background pain. More than half of cancer patients with chronic pain suffer by some form of breakthrough cancer pain. The management of breakthrough cancer pain is comprehensive and includes pharmacological and nonpharmacological approaches. The principal treatment strategies are optimization of regular analgesic medication combined with effective rescues medication. The new transmucosal forms of fentanyl represent an important improvement in our treatment options.

Silver acetate for smoking cessation

BACKGROUND

Silver acetate produces an unpleasant taste when combined with cigarettes, thereby producing an aversive stimulus. It has been marketed in various forms with the aim of extinguishing the urge to smoke, by pairing the urge with an unpleasant stimulus.

OBJECTIVES

The aim of this review was to determine the effectiveness of silver acetate products (gum, lozenge, spray) in promoting smoking cessation.

SEARCH METHODS

We searched the Cochrane Tobacco Addiction Group specialised trials register. Most recent search was in July 2012.

SELECTION CRITERIA

We included randomised trials of silver acetate for smoking cessation with reports of smoking status at least six months after the beginning of treatment.

DATA COLLECTION AND ANALYSIS

We extracted data in duplicate on the type of subjects, the dose and form of silver acetate, the outcome measures, method of randomisation, and completeness of follow-up.The main outcome measure was biochemically validated abstinence from smoking after at least six months follow-up in patients smoking at baseline. Subjects lost to follow-up were counted as continuing smokers. Where appropriate, we performed meta-analysis using a fixed effects model.

MAIN RESULTS

Two studies provided long-term follow-up data on patients randomised to silver acetate or placebo. In one of these studies, there was a third arm, randomised to 2mg nicotine gum. The pooled risk ratio for quitting for silver acetate vs placebo was 1.04 (95% confidence interval 0.69 to 1.57).

AUTHORS' CONCLUSIONS

Existing trials show little evidence for a specific effect of silver acetate in promoting smoking cessation. The confidence intervals for the ratio are quite wide. However, the upper limit of the confidence intervals for a positive effect equates to an absolute increase in the smoking cessation rate of about 4%. Any effect of this agent is therefore likely to be smaller than nicotine replacement therapy. The lack of effect of silver acetate may reflect poor compliance with a treatment whose rationale is to create an unpleasant stimulus.

Drug delivery from the oral cavity: a focus on mucoadhesive buccal drug delivery systems

Since the early 1980s the concept of mucoadhesion has gained considerable interest in pharmaceutical technology. The various advantages associated with these systems made buccal drug delivery as a novel route of drug administration. It prolongs the residence time of the dosage form at the site of application. These systems remain in close contact with the absorption tissue, the mucous membrane, and thus contribute to improved and/or better therapeutic performance of the drug and of both local and systemic effects. This review highlights the anatomy and structure of oral mucosa, mechanism and theories of mucoadhesion, factors affecting mucoadhesion, characteristics and properties of desired mucoadhesive polymers, various types of dosage forms, and general considerations in design of mucoadhesive buccal dosage forms, permeation enhancers, and evaluation methods.

LAY ABSTRACT

Over the past few decades the mucoadhesive buccal drug delivery system has received a great deal of attention to develop mucoadhesive dosage forms to enable the prolonged retention at the site of action, providing a controlled release of drug for improved therapeutic outcome. Mucoadhesive drug delivery gives facility to include a permeation enhancer/enzyme inhibitor or pHmodifier in the formulation and versatility in designing as multidirectional or unidirectional release systems for local and systemic action. Local delivery to tissues of the oral cavity has a number of applications, including treatment of local conditions such as periodontal disease, bacterial and fungal infections, and aphthous stomatitis and vesiculo bullous diseases. For the treatment of chronic diseases, the mucoadhesive buccal drug delivery system allows easily accessibility and is generally well-accepted for administeringdrugs by systemic action.

Drug permeation through biomembranes: cyclodextrins and the unstirred water layer

Surface of the living epithelia is covered with mucus, a gel-like fluid containing mainly water (90-98%) and mucin (2-5%). This aqueous gel-like matrix forms an unstirred water layer (UWL) creating an aqueous diffusion barrier that hampers drug permeation through mucosal barriers. Frequently, the UWL is the main drug permeation barrier, especially in the case of small-molecular-weight lipophilic drugs. Under such conditions drug permeation can often be enhanced by forming water-soluble drug/cyclodextrin complexes. Cyclodextrins enhance drug delivery through biomembranes by increasing drug permeation through the UWL, that is, by increasing the availability of dissolved drug molecules juxtaposed to the membrane surface. Cyclodextrins only enhance drug permeation when the UWL contributes to the permeation barrier. Cyclodextrins do not enhance drug permeation when the permeation resistance of the UWL is much less than that of the membrane itself. The effect depends also on the physicochemical properties of the drug. As a rule the best results are obtained for lipophilic drugs that are poorly soluble in water, that form water-soluble complexes with cyclodextrins and that possess, as dissolved drug molecules, relatively high permeability through lipophilic biomembranes. It is extremely important to optimize drug vehicles with regard to the amount of cyclodextrin. Too much or too little cyclodextrin will lead to less than optimal drug availability. Good understanding of cyclodextrin complexation and how cyclodextrin affect drug permeation through biomembranes is essential for successful development of cyclodextrin-containing drug formulations.

[Preparation and quality control of pyridostigmine bromide orally disintegrating tablet]

OBJECTIVE

To prepare orally disintegrating tablets containing pyridostigmine bromide and optimize formulations.

METHODS

Solid dispersion was prepared using solvent evaporation-deposition method. The formulation was optimized by central composite design-response surface methodology (RSM plus CCD) with disintegration time as a reference parameter.

RESULTS

The orally disintegrating tablets showed integrity and were smooth with desirable taste and feel in mouth. The disintegration time was less than 30 s. The cumulative drug dissolution was around 8.5% (around 2.5 mg which was less than bitterness threshold of pyridostigmine bromide of 3 mg) within 5 min in water while the cumulative drug dissolution was higher than 95% within 2 min in 0.1 N HCl.

CONCLUSION

The orally disintegrating tablets are reasonable in formulation, feasible in technology and patient-friendly.

Investigating the effect of Aloe vera gel on the buccal permeability of didanosine

The buccal mucosal route offers several advantages but the delivery of certain drugs can be limited by low membrane permeability. This study investigated the buccal permeability properties of didanosine (ddI) and assessed the potential of Aloe vera gel (AVgel) as a novel buccal permeation enhancer. Permeation studies were performed using Franz diffusion cells, and the drug was quantified by UV spectroscopy. Histomorphological evaluations were undertaken using light and transmission electron microscopy. The permeability of ddI was concentration-dependent, and it did not have any adverse effects on the buccal mucosae. A linear relationship (R² = 0.9557) between the concentrations and flux indicated passive diffusion as the mechanism of drug transport. AVgel at concentrations of 0.25 to 2 %w/v enhanced ddI permeability with enhancement ratios from 5.09 (0.25 %w/v) to 11.78 (2 %w/v) but decreased permeability at 4 and 6 %w/v. Ultrastructural analysis of the buccal mucosae treated with phosphate buffer saline pH 7.4 (PBS), ddI/PBS, and ddI/PBS/AVgel 0.5 %w/v showed cells with normal plasmalemma, well-developed cristae, and nuclei with regular nuclear envelopes. However, cells from 1, 2, and 6 %w/v AVgel-treated mucosae showed irregular nuclear outlines, increased intercellular spacing, and plasmalemma crenulations. This study demonstrates the potential of AVgel as a buccal permeation enhancer for ddI to improve anti-HIV and AIDS therapy.

Localized reduction of gingival inflammation using site-specific therapy with a topical gingival patch

METHODS

Sites of inflammation were identified on subjects with moderate-to-severe chronic periodontitis, and were allocated to either patch placement or untreated controls, both for 24 hours. Conventional treatment with scaling and root planing was postponed during the study period. Inflammation was evaluated measuring neutrophilic activity using gingival crevicular fluid (GCF) beta-glucuronidase (b-glu) levels, and clinical response was evaluated using the gingival index (GI).

RESULTS

A total of 26 patients were recruited and 36 sites examined, with 22 sites on which the patch was placed and 14 controls. GCF b-glu levels at 24 hours were reduced following patch placement, significantly more so than with controls (17/22 vs. 3/14 sites, respectively; p = 0.002). The patch placement resulted in a significant reduction in mean b-glu levels (-2.52 +/- 1.62), with a reduction from baseline of 29.7%. This compared to untreated controls, for whom the mean b-glu levels and percent change from baseline increased (2.14 +/- 0.89 and 33%, respectively). At 24 hours, GI response rate for treated sites was better than for control sites (18/21 vs. 7/14; p = 0.053). No adverse events were reported in either group.

CONCLUSION

This pilot study indicates that a topical gingival patch promotes reduction of gingival inflammation. Further clinical testing of this novel treatment of gingival inflammation is warranted.

Interventions for the management of dry mouth: topical therapies

BACKGROUND

Xerostomia (the feeling of dry mouth) is a common symptom especially in older adults. Causes of dry mouth include medications, autoimmune disease (Sjögren's Syndrome), radiotherapy or chemotherapy for cancer, hormone disorders and infections.

OBJECTIVES

To determine which topical treatments for dry mouth are effective in reducing this symptom.

SEARCH METHODS

We searched the following electronic databases: the Cochrane Oral Health Group Trials Register (28 October 2011), The Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, Issue 4 2011), MEDLINE via OVID (1950 to 28 October 2011), EMBASE via OVID (1980 to 28 October 2011), CINAHL via EBSCO (1980 to 28 October 2011), AMED via OVID (1985 to 28 October 2011), CANCERLIT via PubMed (1950 to 28 October 2011).

SELECTION CRITERIA

We included randomised controlled trials of topical interventions such as lozenges, sprays, mouthrinses, gels, oils, chewing gum or toothpastes for the treatment of dry mouth symptom. We classified interventions into two broad categories, saliva stimulants and saliva substitutes, and these were compared with either placebo or another intervention. We included both parallel group and crossover trials.

DATA COLLECTION AND ANALYSIS

Two or more review authors independently carried out data extraction and assessed risk of bias. Trial authors were contacted for additional information as required.

MAIN RESULTS

Thirty-six randomised controlled trials involving 1597 participants met the inclusion criteria. Two trials compared saliva stimulants to placebo, nine trials compared saliva substitutes to placebo, five trials compared saliva stimulants directly with saliva substitutes, 18 trials directly compared two or more saliva substitutes, and two trials directly compared two or more saliva stimulants. Only one trial was at low risk of bias and 17 were at high risk of bias. Due to the range of interventions, comparisons and outcome measures in the trials, meta-analysis was possible for only a few comparisons. Oxygenated glycerol triester (OGT) saliva substitute spray shows evidence of effectiveness compared to an electrolyte spray (standardised mean difference (SMD) 0.77, 95% confidence interval (CI) 0.38 to 1.15) which corresponds to approximately a mean difference of 2 points on a 10-point visual analogue scale (VAS) for mouth dryness. Both integrated mouthcare systems (toothpaste + gel + mouthwash) and oral reservoir devices show promising results but there is insufficient evidence at present to recommend their use. Although chewing gum is associated with increased saliva production in the majority of those with residual capacity, there is no evidence that gum is more or less effective than saliva substitutes.

AUTHORS' CONCLUSIONS

There is no strong evidence from this review that any topical therapy is effective for relieving the symptom of dry mouth. OGT spray is more effective than an aqueous electrolyte spray (SMD 0.77, 95% CI 0.38 to 1.15) which is approximately equivalent to a mean difference of 2 points on a 10-point VAS scale for mouth dryness. Chewing gums appear to increase saliva production in those with residual secretory capacity and may be preferred by patients, but there is no evidence that gum is better or worse than saliva substitutes. Integrated mouthcare systems and oral reservoir devices may be helpful but further research is required to confirm this. Well designed, adequately powered randomised controlled trials of topical interventions for dry mouth, which are designed and reported according to CONSORT guidelines, are required to provide evidence to guide clinical care. For many people the symptom of dry mouth is a chronic problem and trials should evaluate whether treatments are palatable, effective in reducing xerostomia, as well as the long-term effects of treatments on quality of life of those with chronic dry mouth symptoms.

Development and evaluation of mucoadhesive buccal patches of flurbiprofen

In the present study, an attempt was made to formulate mucoadhesive buccal patches of flurbiprofen (FBN) in order to enhance solubility. Solubity enhancement was attempted by making solid dispersion of drug with beta-CD (cyclodextrin). Initially preformulation were carried out using reported methods. Buccal patches were prepared by solvent casting technique using polymers like polyvinyl alcohol (PVA), sodium carboxymethyl cellulose (SCMC), and hydroxypropyl methylcellulose (HPMC). The prepared patches were evaluated for their weight variation, thickness, folding endurance, surface pH, swelling index, in vitro residence time, in vitro permeation studies, drug content uniformity and bioadhesion test.

An in situ gelling buccal spray containing platelet lysate for the treatment of oral mucositis

Oral mucositis is an inflammatory disease of the mucosa lining oral cavity which leads to atrophy of the epithelium and to its ulceration to form chronic lesions. Many studies, both in vitro and in vivo, have disclosed the effectiveness of growth factors derived from platelets to enhance cell proliferation, differentiation, chemotaxis, angiogenesis and extracellular matrix synthesis involved in the healing of tissues. Despite potential usefulness of growth factors, animal-derived or genetically engineered ones are currently scarcely available for regenerative therapies. The aim of the present work was to study an in situ gelling formulation to be delivered by a spraying device to the oral cavity affected by mucositis. A vehicle based on Poloxamer 407 (F127) and sodium alginate (LVG) was developed. An extemporaneous loading of the vehicle with PL was achieved. The formulation was able to quickly thermogelify at 34-35°C with a viscosity at 8°C suitable for spraying; moreover it was characterized by good mucoadhesive properties. ELISA assay evidenced that at time zero the growth factor PDGF AB was compatible with the vehicle. The in vitro wound healing test showed that the formulation enhanced cell growth as PL alone even after 72 h of contact without cell apoptosis. The overall results indicate that PL loaded in the in situ gelling F127 and LVG vehicle can be profitably employed to treat buccal mucositis.

Fentanyl buccal tablets for breakthrough pain in highly tolerant cancer patients: preliminary data on the proportionality between breakthrough pain dose and background dose

CONTEXT

Cancer patients receiving high doses of opioids as background medication are challenging, and it would be useful clinically to know whether a rapid-onset opioid (ROO) for breakthrough cancer pain (BTcP) may be started at a dose proportional to the background opioid dose.

OBJECTIVES

The aim of this study was to assess the efficacy and safety of the fentanyl buccal tablet (FBT) in doses proportional to the opioid dose administered for background analgesia in a sample of patients with BTcP who were receiving high doses of opioids.

METHODS

Twelve patients who were receiving opioids for background analgesia at doses equivalent to more than 500 mg of oral morphine and had adequately controlled pain were prospectively recruited. BTcP was treated with proportional doses of FBT: patients receiving 600 mg of oral morphine equivalents were administered 1000 μg of FBT, patients receiving 900 mg of oral morphine equivalents were administered 1500 μg of FBT, and so on. For each episode of BTcP, trained nurses collected pain intensity (on a 0-10 numerical rating scale) and emerging problems when called for increases in pain considered to be severe in intensity by patients (T0) and 15 minutes after FBT administration (T15).

RESULTS

Patients were receiving mean doses of oral morphine equivalents of 1340 mg (± 585; range 720-2400). Seventy-nine events were treated with FBT (6.6 ± 4.9 for each patient). The median pain intensity of BTcP events was 8 (range 7-10), and the mean dose of FBT administered was 2233 μg (± 975; range 1200-4000). In most events, a decrease in pain intensity >33% and >50% was observed (n=14 and n=48, respectively) 15 minutes after the administration of FBT. Data on 11 episodes were missed. Only six events were unsuccessfully treated. In all the patients, the level of adverse effects after FBT administration was mild and indistinguishable from that associated with the background opioid analgesia.

CONCLUSION

FBT in doses proportional to the high doses of opioids used for background analgesia was efficacious and well tolerated when administered for BTcP. Controlled studies with a specific design and a large number of patients should confirm such preliminary results.

Preparation and solid-state characterization of ball milled saquinavir mesylate for solubility enhancement

Saquinavir is an anti-retroviral drug with very low oral bioavailability (e.g. 0.7-4.0%) due to its affinity toward efflux transporters (P-gp) and metabolic enzymes (CYP3A4). The aim of this study was to characterize the effects of high-energy ball milling on saquinavir solid-state characteristics and aqueous solubility for the design of effective buccal drug delivery systems. The solubility of saquinavir mesylate was evaluated in simulated saliva before and after milling for 1, 3, 15, 30, 50, and 60 h. To elucidate changes in crystallinity and long-range structure in the drug, analyses of the milled powders were performed using XRD, ATR-IR, DSC/TGA, BET surface area, EDX and SEM. In addition, the effects of milling time on saquinavir solubility were statistically correlated using repeated measures ANOVA. Results of this study indicate that the milling of saquinavir mesylate produces nanoporous particles with unique surface structures, thermal properties, and increased aqueous solubility. Optimal milling time occurred at 3h and corresponded to a 9-fold solubility enhancement in simulated saliva. Thermal analysis revealed only a slight decrease in melting point (T(m)) from 242 °C to 236 °C after 60 h milling. XRD diffractograms indicate a gradual crystalline-to-amorphous transition with some residual crystallinity remaining after 60 h milling time. Unstable polymorphic structures appeared between 15 and 30 h which were converted to more stable isomorphs at 60 h. Aggregate formation also seems to occur after 15 h but no metal contamination of the drug was observed during the milling process as determined by EDX analysis. In conclusion, high-energy ball milling may be a method of choice for improving the solubility of saquinavir and facilitating novel drug formulations design.

Buccal midazolam or rectal diazepam for treatment of residential adult patients with serial seizures or status epilepticus

OBJECTIVES

To compare the efficacy and tolerability of buccal midazolam with rectal diazepam as emergency treatment in residential adults with convulsive or non-convulsive serial seizures or status epilepticus (SE), and ascertain the preference between the two treatment options among the patients and the nursing staff.

MATERIALS AND METHODS

  The nursing staff of our residential epilepsy centre treated 80 episodes of serial seizures or SE lasting more than 5 min alternating with rectal diazepam or buccal midazolam. The dose of each study drug was tailored individually. The primary outcome measure was defined as cessation of seizure activity within 10 min without seizure relapse within 2 h.

RESULTS

Convulsive SE was treated promptly, after a mean of 6.2 min, and terminated faster with buccal midazolam than with rectal diazepam; i.e. after a mean of 2.8 vs 5.0 min, respectively (n = 0.012). The other subcategories of emergency situations were treated after a mean of 25.0 min, and the seizure activity ceased after a mean of 7.4 min in the diazepam group and 7.6 min in the midazolam group (NS). The success rate was 83.3% in the diazepam group and 74.4% in the midazolam group (NS). The difference was mostly due to slightly more seizure relapses during the first 2 h in the midazolam group. Both treatment options were well tolerated, temporary tiredness being the most frequently occurring adverse effect. All the nursing staff and six of the seven patients who gained experience with both treatment options favoured the buccal route.

CONCLUSIONS

  Buccal midazolam appeared to be at least as effective as rectal diazepam with little or no side effects. The buccal administration was easy to handle and socially more acceptable than the rectal route.

Effect of fentanyl buccal tablet on pain-related anxiety: a 4-week open-label study among opioid-tolerant patients with chronic and breakthrough pain

OBJECTIVE

To evaluate the effect of fentanyl buccal tablet (FBT) on pain-related anxiety in opioid-tolerant patients with chronic pain and breakthrough pain (BTP).

DESIGN

This study consisted of a screening visit, open-label titration period, and 4-week open-label treatment period.

SETTING

Thirty-one US study centers.

PATIENTS

Opioid-tolerant adults with chronic, persistent pain experiencing 1-4 BTP episodes per day at baseline. Two hundred eighteen patients were enrolled in this study; 180 completed the titration period; and 169 completed the treatment period.

INTERVENTION

Patients were treated with FBT (100-800 microg) for BTP episodes for 4 weeks while continuing their around-the-clock opioid regimens.

MAIN OUTCOME MEASURES

Change from baseline in the Pain Anxiety Symptoms Scale (PASS) total score at the final visit.

RESULTS

Based on a mean baseline PASS total score of 82.6, study patients had a high level of anxiety; 92 patients (42 percent) had a history of anxiety disorders. The change from baseline in PASS total score was not statistically significant (mean change, -1.6; p = 0.322). Numerical improvements were reported in some secondary measures (eg, Beck Depression Inventory total score /mean change, -1.1; p = 0.038) and categorical measures (eg, Pain Flare Treatment Satisfaction, Patient Assessment of Function, and Clinician Assessment of Patient Function ratings). FBT was generally well tolerated, with no serious adverse events related to study drug.

CONCLUSIONS

Four weeks of treatment with FBT did not reduce anxiety to a clinically meaningful extent, although improvement was reported in several secondary measures of functioning. Further research is needed to assess the impact of treatment for BTP on anxiety symptoms in opioid-tolerant patients with BTP.

Effect of surfactants and pH on naltrexone (NTX) permeation across buccal mucosa

The objective of this pre-formulation study was to systematically investigate the effects of two surfactants (Brij 58(®) and Tween 80(®)) and change in solution pH on in vitro permeation of naltrexone HCl (NTX-HCl) across tissue engineered human buccal mucosa. For the study, 10mg/ml solutions of Tween 80(®) (0.1 and 1%, w/v) and Brij 58(®) (1%, w/v) were prepared in standard artificial saliva buffer solution (pH 6.8). For studying pH effects, solution pH was adjusted to either 7.5 or 8.2. As controls, three concentrations of NTX-HCl (2.5, 10 and 25mg/ml) were prepared. Using NTX standard solution (10mg/ml; pH 6.8), the permeation was observed between in vitro human and ex vivo porcine mucosa. It was observed that Brij 58(®) increased the permeation rates of NTX significantly. The flux of 10mg/ml solution (pH 6.8) increased from 1.9 ± 0.6 (× 10(2)) to 13.9 ± 2.2 (× 10(2))μg/(cm(2)h) (approximately 6-fold) in presence of 1% Brij 58(®). Increasing pH of NTX-HCl solution was found to increase the drug flux from 1.9 ± 0.6 (× 10(2)) (pH 6.8) to 3.0 ± 0.6 (× 10(2)) (pH 7.4) and 8.0 ± 3.5 (× 10(2)) (pH 8.2)μg/(cm(2)h), respectively. Histological analyses exhibited no tissue damage due to exposure of buccal tissue to Brij 58(®). The mean permeability coefficients (K(p)) for 2.5, 10 and 25mg/ml solutions of NTX-HCl (pH 6.8) were 5.0 (× 10(-2)), 1.8 (× 10(-2)) and 3.2 (× 10(-2))cm/h, respectively, consistent with data from published literature sources. Increase of NTX flux observed with 1% Brij 58(®) solution may be due to the effects of ATP. Increase in flux and the shortening of lag time observed by increasing in solution pH confirmed earlier finding that distribution coefficient (logD) of NTX is significantly affected by small increments in pH value and therefore plays an important role in NTX permeation by allowing faster diffusion across tissue engineered human buccal tissue.

Long-term dosing, safety, and tolerability of fentanyl buccal tablet in the management of noncancer-related breakthrough pain in opioid-tolerant patients

OBJECTIVE

To evaluate the long-term dosing, safety, and tolerability of fentanyl buccal tablet (FBT) in a large cohort of opioid-tolerant patients with chronic noncancer pain and breakthrough pain (BTP).

DESIGN

Combined analysis of three double-blind, placebo-controlled, and two open-label studies.

RESULTS

Of 1160 patients who received ≥1 dose of FBT, 83% achieved a successful dose, ranging from 100 to 800 μg, mostly at 600 or 800 μg. Not all of the patients included in this analysis were enrolled in long-term studies and 156 (13%) patients were still receiving ongoing treatment when their study site closed. Median treatment duration was 106.0 days. The mean FBT dose in the post-titration population (n = 946) increased from 2108 to 3132 μg/day, with ≥1 FBT dose increase in 27% of patients; most dose increases occurred during the first 6 months. The FBT daily dose as a proportion of the daily opioid dose remained fairly stable (59-65%) throughout the treatment period. Overall, 925 (80%) enrolled patients had ≥1 adverse event (AE). The most frequent AEs were nausea (21% of patients), vomiting (11%), dizziness (10%), and headache (10%). Common AEs generally occurred within 7 days of starting treatment and lasted for ≤2 days. Serious AEs occurred in 136 (12%) patients and included six deaths (none related to FBT) and 11 instances of opioid overdose (all with satisfactory resolution). AE-related discontinuations occurred in 163 (14%) patients and were similar to the common AEs.

CONCLUSIONS

Despite the limitations, including the controlled clinical setting, this pooled analysis of several clinical studies provides valuable information for the long-term management of BTP with FBT. Patients require regular evaluation and, when necessary, adjustment of opioid medications to maintain adequate pain control. FBT was generally safe and well tolerated in this setting.