Double-blind, randomised, placebo-controlled study of two concentrations of azelastine eye drops in seasonal allergic conjunctivitis or rhinoconjunctivitis

A Novel Approach of Drug Localization through Development of Polymeric Micellar System Containing Azelastine HCl for Ocular Delivery

BACKGROUND

Development of polymeric micelles for the management of allergic conjunctivitis to overcome the limitations of topical installation, such as poor patient compliance, poor stromal permeability, and significant adverse effects, increase precorneal residence time and efficacy, and also control the release of drug at the target site.

OBJECTIVE

The investigation was aimed at developing a polymeric micellar system of Azelastine HCl for Ocular Delivery.

METHODS

Drug loaded micelles of tri-block copolymers Pf 127 were prepared by Thin Film hydration method. The polymeric micelles formulations (F1 to F9) were assessed for entrapment efficiency, micelle size, in vitro permeation, ex vivo transcorneal permeation, in vivo Ocular Irritation, and Histology.

RESULTS

Optimized micelles formulation (F3), with the lowest micelle size of 92 nm, least polydispersity value of 0.135, highest entrapment efficiency of 95.30 ± 0.17%, and a cumulative drug permeation of 84.12 ± 1.26% in 8h, was selected to develop pH-sensitive micelles loaded carbopol in situ gel. The optimized in situ gel (G4) proved to be superior in its ex vivo transcorneal permeation when compared with Market Preparation and pure drug suspension, exhibiting 43.35 ± 1.48% Permeation with zero-order kinetics (r2 = 0.9944) across goat cornea. Transmission Electron microscopy revealed spherical polymeric micelles trapped in the gel matrix. A series of experiments showed hydration capability, non-irritancy, and histologically safe gel formulation that had appropriate handling characteristics.

CONCLUSION

A controlled release pH-sensitive ocular formulation capable of carrying the drug to the anterior section of the eye via topical delivery was successfully developed for the treatment of allergic conjunctivitis.

Topical antihistamines and mast cell stabilisers for treating seasonal and perennial allergic conjunctivitis

BACKGROUND

Seasonal/perennial allergic conjunctivitis is the most common allergic conjunctivitis, usually with acute manifestations when a person is exposed to allergens and with typical signs and symptoms including itching, redness, and tearing. The clinical signs and symptoms of allergic conjunctivitis are mediated by the release of histamine by mast cells. Histamine antagonists (also called antihistamines) inhibit the action of histamine by blocking histamine H1 receptors, antagonising the vasoconstrictor, and to a lesser extent, the vasodilator effects of histamine. Mast cell stabilisers inhibit degranulation and consequently the release of histamine by interrupting the normal chain of intracellular signals. Topical treatments include eye drops with antihistamines, mast cell stabilisers, non-steroidal anti-inflammatory drugs, combinations of the previous treatments, and corticosteroids. Standard treatment is based on topical antihistamines alone or topical mast cell stabilisers alone or a combination of treatments. There is clinical uncertainty about the relative efficacy and safety of topical treatment.

OBJECTIVES

The objective of this review was to assess the effects of topical antihistamines and mast cell stabilisers, alone or in combination, for use in treating seasonal and perennial allergic conjunctivitis.

SEARCH METHODS

We searched CENTRAL (which contains the Cochrane Eyes and Vision Trials Register) (2014, Issue 7), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE (January 1946 to July 2014), EMBASE (January 1980 to July 2014), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrials.gov) and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 17 July 2014. We also searched the reference lists of review articles and relevant trial reports for details of further relevant publications.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing topical antihistamine and mast cell stabilisers, alone or in combination, with placebo, no treatment or to any other antihistamine or mast cell stabiliser, or both, that examined people with seasonal or perennial allergic conjunctivitis, or both. The primary outcome was any participant-reported evaluation (by questionnaire) of severity of four main ocular symptoms: itching, irritation, watering eye (tearing), and photophobia (dislike of light), both separately and, if possible, by an overall symptom score. We considered any follow-up time between one week and one year.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed risk of bias. Disagreements were resolved by discussion among review authors and the involvement of a third review author. We followed standard methodological approaches used by Cochrane.

MAIN RESULTS

We identified 30 trials with a total of 4344 participants randomised, with 17 different drugs or treatment comparisons. The following antihistamines and mast cell stabilisers were evaluated in at least one RCT: nedocromil sodium or sodium cromoglycate, olopatadine, ketotifen, azelastine, emedastine, levocabastine (or levocabastine), mequitazine, bepotastine besilate, combination of antazoline and tetryzoline, combination of levocabastine and pemirolast potassium. The most common comparison was azelastine versus placebo (nine studies).We observed a large variability in reporting outcomes. The quality of the studies and reporting was variable, but overall the risk of bias was low. Trials evaluated only short-term effects, with a range of treatment of one to eight weeks. Meta-analysis was only possible in one comparison (olopatadine versus ketotifen). There was some evidence to support that topical antihistamines and mast cell stabilisers reduce symptoms and signs of seasonal allergic conjunctivitis when compared with placebo. There were no reported serious adverse events related to the use of topical antihistamine and mast cell stabilisers treatment.

AUTHORS' CONCLUSIONS

It seems that all reported topical antihistamines and mast cell stabilisers reduce symptoms and signs of seasonal allergic conjunctivitis when compared with placebo in the short term. However, there is no long-term data on their efficacy. Direct comparisons of different antihistamines and mast cell stabilisers need to be interpreted with caution. Overall, topical antihistamines and mast cell stabilisers appear to be safe and well tolerated. We observed a large variability in outcomes reported. Poor quality of reporting challenged the synthesis of evidence.

Therapeutic management of allergic diseases

Allergic diseases are characterized by the activation of inflammatory cells and by a massive release of mediators. The aim of this chapter was to describe succinctly the modes of action, indications, and side effects of the major antiallergic and antiasthmatic drugs. When considering the ideal pharmacokinetic characteristics of a drug, a poorly metabolized drug may confer a lower variability in plasma concentrations and metabolism-based drug interactions, although poorly metabolized drugs may be prone to transporter-based disposition and interactions. The ideal pharmacological properties of a drug include high binding affinity, high selectivity, and appropriate association and dissociation rates. Finally, from a patient perspective, the frequency and route of administration are important considerations for ease of use.

Emerging drugs for ocular allergy

Ocular allergy is a common condition that usually affects the conjunctiva of the eye and is, therefore, often referred to as allergic conjunctivitis. The severity of the disease can range from mild itching and redness, as seen in seasonal allergic conjunctivitis, to the more severe, sight-threatening forms such as vernal and atopic keratoconjunctivitis. The central mechanism in the pathogenesis of these diseases is IgE-mediated mast cell degranulation and activation of T lymphocytes, eosinophils and conjunctival structural cells. The pharmacotherapy of allergic conjunctivitis consists of several classes of drugs: antihistamines, mast cell stabilisers, dual-acting agents and corticosteroids. None of the available drugs completely abolishes the development of ocular allergy. For this reason, new topical antiallergic/anti-inflammatory agents are currently and continually under clinical trials. This review provides a background to ocular allergic diseases, the medical need for therapy and current and potential new treatments.

Ocular Allergic Disease: Mechanisms, Disease Sub-types, Treatment

Ocular allergy refers to a variety of hypersensitivity disorders that affect the lid, conjunctiva, and/or cornea. Its incidence is estimated at over 20% of the general population in the United States. This review will discuss the various forms of ocular allergy, their pathophysiology, clinical presentation, and treatment. New frontiers in mechanisms, therapy, and management in the office are emphasized throughout.

Efficacy and safety of topical azelastine compared with topical mitomycin C in patients with allergic conjunctivitis

PURPOSE

To compare the efficacy and safety of topical azelastine with topical mitomycin C (MMC) in patients with allergic conjunctivitis.

METHODS

Sixty-three patients (29 male, 29 female; 34 in the age range of 6 to 65 years) with allergic conjunctivitis were enrolled in this study. The patients were randomly assigned to receive topical azelastine 0.02% (n = 31) or topical MMC (0.2 mg/10 mL) (n = 31) four times daily for 3 months. Follow-up examinations were done at 2 weeks to examine side effects of the medications and again at 4 weeks to assess the outcome of treatment. The eyes were examined for relief of symptoms, cure of signs, and the appearance of side effects with use of these drugs.

RESULTS

The mean age of the patients in this study was 34.8 +/- 17.3 years. The age of patients in the MMC group was significantly higher than patients in the azelastine group (mean +/- SD, 25.2 +/- 13.5 years). More patients in the MMC group had relief of symptoms like redness [25 (80.7%) in the MMC group versus 19 (55.9%) in the azelastine group; p= 0.033], photophobia [11 (35.5%) in the MMC group versus six (17.7%) in the azelastine group; not significant], discharge [17 (54.8%) in the MMC group versus 11 (32.3%) in the azelastine group; not significant], and foreign body sensation [21 (67.7%) in the MMC group versus 16 (47.1%) in the azelastine group; not significant], while more patients in the azelastine group had relief of lacrimation [14 (41.2%) in the azelastine group versus 10 (32.3%) in the MMC group; not significant] and pain [12 (35.3%) in the azelastine group versus eight (25.8%) in the MMC group; not significant]. The MMC group also showed a greater decrease in follicles [31 (100.0%) in the MMC group versus six (17.7%) in the azelastine group; p= 0.0001] and papillae [29 (93.6%) in the MMC group versus four (11.8%) in the azelastine group; p= 0.0001]. Both drugs were found to be equally effective in relieving itching [18 (58.1%) in the MMC group versus 18 (52.9%) in the azelastine group; not significant]. In the MMC group, 27 (87.1%) patients had conjunctival hyperemia, 28 (90.3%) patients had episcleritis, and 29 (93.6%) patients had irritation. The use of topical azelastine did not cause any adverse event.

CONCLUSIONS

Though this was a short-term study, we found topical MMC to be more effective than topical azelastine in the treatment of allergic conjunctivitis both in terms of relief of symptoms and resolution of signs. The use of topical MMC in low doses does not cause any significant adverse effect.

Topical azelastine in perennial allergic conjunctivitis

OBJECTIVE

Azelastine is a selective H(1)-receptor antagonist that inhibits histamine release and interferes with activation of several other mediators of allergic inflammation. Together with demonstrated efficacy in seasonal allergic conjunctivitis, azelastine indicated a therapeutic potential for perennial allergic conjunctivitis (PAC). The present study aimed to evaluate azelastine eye drops in patients with PAC compared to placebo.

RESEARCH DESIGN AND METHODS

A multinational trial in 22 centres randomised 139 patients to twice-daily treatment for 6 weeks with masked 0.05% azelastine eye drops, matching masked placebo, or open-label levocabastine. Randomisation required a sum itching and conjunctival redness score of at least 3 (0-6 scale) after 1 week of placebo. The change in sum score was evaluated during treatment.

RESULTS

Azelastine significantly improved itching and conjunctival redness compared to placebo (p < 0.001) with global tolerability that was not substantially different from placebo. On day 7, the mean symptoms sum score improved with azelastine by 1.9 +/- 1.1 and with levocabastine by 1.5 +/- 1.2 compared to placebo (0.6 +/- 1.1) from baseline values of 3.7-3.8. The sum scores continued to improve up to day 42. Daily patient logs confirmed the clinically assessed scores. Most frequent adverse events following azelastine were bitter taste and application site reaction.

CONCLUSIONS

Topical azelastine progressively improved itching and conjunctival redness in PAC patients compared to placebo and was at least as effective as levocabastine. Rapid relief is consistent with H(1)-receptor antagonist action, while continued improvement up to 6 weeks may be consistent with mechanisms involving other mediators of allergic inflammation.

Comparison of the efficacy and tolerability of topically administered azelastine, sodium cromoglycate and placebo in the treatment of seasonal allergic conjunctivitis and rhino-conjunctivitis

OBJECTIVE AND SETTING

Azelastine (AZE) in a novel, eye drop, formulation, was compared with topically applied sodium cromoglycate (SCG) and placebo (PLA) in the treatment of seasonal allergic conjunctivitis or rhino-conjunctivitis in a multicentre, parallel group study.

RESEARCH DESIGN

144 subjects ranging in age from 16 to 65 years participated. All had at least a 2-year history of seasonal allergic conjunctivitis and were symptomatic at the time of inclusion. Medications were administered topically either twice daily (AZE/PLA) or four times daily (SCG) over a 2-week treatment period. Method and outcome measures: Azelastine and placebo were compared double-blind; the comparison versus SCG was carried out in an open manner. Itching, redness, flow of tears, eyelid swelling, foreign-body sensation, photophobia, soreness and discharge were scored on a 4-point severity scale.

RESULTS

Results for the decrease of main conjunctivitis symptoms (itching, tearing and conjunctival redness) showed a marked effect for both active treatments on day 3 with a sustained improvement on days 7 and 14. A clear response to treatment (an improvement of sum scores for day 3 of >/=3 points compared to baseline) occurred in 85.4% of azelastine-treated patients, 83.0% of sodium cromoglycate patients and 56.3% of placebo patients. Response rates for both active treatments were statistically superior to those for placebo (azelastine p = 0.005; sodium cromoglycate p = 0.007). Global assessment of efficacy was at least 'satisfactory' for 90.0% of azelastine patients, 81.3% of sodium cromoglycate patients and 66.3% of placebo-treated patients. The most frequent adverse effects were transient application site reactions which tended to disappear with increasing duration of treatment, and, less frequently, taste perversion.

CONCLUSION

The results of this study indicate that the therapeutic use of azelastine eye drops in patients with seasonal allergic conjunctivitis or rhino-conjunctivitis can be recommended.

Evaluation of the onset and duration of effect of azelastine eye drops (0.05%) versus placebo in patients with allergic conjunctivitis using an allergen challenge model

OBJECTIVE

The trial evaluated the effectiveness of the investigational antihistaminic and antiallergic compound Azelastine Eye Drops (AZE) in the treatment of allergic conjunctivitis using an allergen challenge model.

DESIGN

Randomized, double-blind, placebo-controlled, paired-eye study.

PARTICIPANTS

Adults with a history of allergic conjunctivitis (>/=2 years) who were asymptomatic throughout the trial, had a positive skin test (cat dander, grass, or ragweed pollen within the last year), and had a positive conjunctival reaction (score 2+ or more for itching and redness in both eyes on a 0-4 scale) during two separate conjunctival provocation tests (CPT) before randomization.

METHODS

Eighty patients underwent a 2-week screening period (visits 1 and 2) that included a CPT during visit 1 to establish the allergen threshold dose and a second confirmatory CPT performed at visit 2. Eye symptom assessments for itching (evaluated by patient) and conjunctival redness (evaluated by physician) were performed 5 and 10 minutes after CPT using a 5-point scale (from 0 = none to 4+ = severe). Qualified patients were randomized to receive one drop of AZE (0.015 mg of azelastine hydrochloride) in one eye and one drop of placebo in the other eye 20 minutes before CPT at visit 3 (onset) and 8 or 10 hours before CPT at visit 4 (duration).

MAIN OUTCOME MEASURES

Individual severity scores for itching (evaluated by patient) and conjunctival redness (evaluated by physician) for each eye at 3, 5, and 10 minutes after CPT at visits 3 and 4 using a 5-point scale (0 = none to 4+ = very severe).

RESULTS

Each of the 80 randomized patients completed the trial. Mean itching and conjunctival redness scores at visit 3 (onset) were significantly lower (P: < 0.001) in the AZE-treated eyes than in the placebo-treated eyes. At visit 4 (duration), mean itching and conjunctival redness scores (P: </= 0.003) for the 8-hour group and mean itching scores (P: </= 0.001) for the 10-hour group were significantly lower in the AZE-treated eyes than in the placebo-treated eyes. Significant differences in mean tearing and chemosis severity scores were also seen at visit 3 (onset) and visit 4 (duration) in the AZE-treated eyes when compared with the placebo-treated eyes. Treatment with AZE was well tolerated.

CONCLUSIONS

Therapy of experimentally induced allergic conjunctivitis with AZE was highly effective, with an onset of action seen within 3 minutes and a duration of effect of at least 8 to 10 hours.

Azelastine eye drops in the treatment of seasonal allergic conjunctivitis or rhinoconjunctivitis in young children

In a randomised, multicentre study, the effect of azelastine eye drops (n = 51 patients) was compared in a double-blind manner with placebo eye drops (n = 30 patients) and in an open manner with levocabastine eye drops (n = 32 patients) during a 14-day treatment period involving 113 children (aged 4 to 12 years) suffering from seasonal allergic conjunctivitis/rhinoconjunctivitis. The primary variable was the response rate defined as the number of patients showing an improvement after three days of treatment of at least three score points, from a minimum baseline score of six, in the main ocular symptoms of itching, conjunctival redness and lacrimation (each assessed on a four-point scale). Patients discontinuing due to inefficacy were regarded as non-responders. The mean response rate in the azelastine eye drops group (74%) was significantly higher (p < 0.01) than that in the placebo group (39%) and comparable with that in the levocabastine group. The response rates assessed by the patients in their diaries were very similar. Significant differences (p < 0.01) for azelastine compared with placebo were observed on days 3 and 14 in the mean sum scores for the three main symptoms and for a total of eight eye symptoms. The overall assessment of efficacy confirmed the superiority of both active treatments compared with placebo. Adverse drug reactions were reported in 23% of placebo-, 35% of azelastine- and 38% of levocabastine-treated patients. These were mainly local irritant effects. Overall tolerability was assessed as very good or good in 80%, 84% and 91% of placebo-, azelastine- and levocabastine-treated patients, respectively. Azelastine eye drops are effective and well-tolerated in children with seasonal allergic conjunctivitis.