Prolonged Effectiveness of Bepotastine Besilate Ophthalmic Solution for the Treatment of Ocular Symptoms of Allergic Conjunctivitis

Efficacy and Toxicity Evaluation of Bepotastine Besilate 1.5% Preservative-Free Eye Drops Vs Olopatadine Hydrochloride 0.2% Bak-Preserved Eye Drops in Patients with Allergic Conjunctivitis

Purpose

To study the efficacy and toxic effects of bepotastine besilate 1.5% preservative-free (BB-PF) and olopatadine 0.2% BAK-preserved (OL-BAK) drops on the ocular surface of patients with allergic conjunctivitis.

Patients and Methods

Ninety-seven patients with allergic conjunctivitis diagnosis participated in a prospective, multicenter, randomized, double-blind, controlled, parallel-group clinical trial. Patients received either BB-PF (n=48) or OL-BAK (n=49), both administered once daily in the morning. The patients were followed for 60 days. Ocular itching was the primary outcome measure. Secondary outcomes included ocular symptoms, signs, and non-ocular symptoms associated with rhinoconjunctivitis. Conjunctival impression cytology (CIC) was performed to evaluate histopathological changes related to the toxic effects of preservatives.

Results

BB-PF treatment was associated with a 1.30 more probability of diminished ocular itching than OL-BAK (odds ratio (OR)=1.30; 95% CI=(0.96-1.7); p=0.086). No statistically significant differences were found between treatments in the resolution of other ocular symptoms or signs, except for tearing, which was superior in the BB-PF (OR=1.37; 95% (1.26-1.47); p<0.0001). BB-PF was superior in terms of the resolution of rhinorrhea (p=0.040) and nasal itching (p=0.037). After 60 days of treatment, the BB-PF group exhibited 2.0 times higher probability of having a lower Nelson scale score compared to the OL-BAK group (OR=2.00; 95% CI=(1.19-3.34); p=0.010).

Conclusion

Both medications presented a similar efficacy in terms of the resolution of ocular signs and symptoms associated with ocular conjunctivitis. BB-PF is superior in the resolution of non-ocular symptoms and safer for the ocular surface than OL-BAK.

Ocular itch associated with allergic conjunctivitis: latest evidence and clinical management

Allergic conjunctivitis is one of the most common allergic conditions worldwide. Its incidence is increasing due to changing climate, pollution, increased pollen loads, and the subject's heightened immunological sensitivity in response to these environmental changes. The pathophysiology predominantly involves immunoglobulin E-related mast-cell activation, with release of histamine and other mediators contributing to the propagation of the response by calling in other immune cells and further inflammation. This article presents the evolution of ocular allergy treatments, from vasoconstrictors, to antihistamines and mast-cell stabilizers, to the dual-acting agents, as well as corticosteroid and immunomodulatory options. Future targets for allergy treatment are also discussed.

Efficacy of epinastine hydrochloride ophthalmic solution in allergic conjunctivitis by conjunctival cedar pollen allergen challenge

BACKGROUND

Epinastine hydrochloride is a selective histamine H1 receptor antagonist that also inhibits IgE receptor-mediated histamine release from mast cells.

OBJECTIVE

To show the superiority of epinastine 0.05% ophthalmic solution (epinastine) to placebo ophthalmic solution (placebo) and noninferiority to olopatadine 0.1% ophthalmic solution (olopatadine) for cedar pollen antigen-induced ocular itching and conjunctival hyperemia.

METHODS

The study was conducted in ophthalmologically asymptomatic adult volunteers with seasonal allergic conjunctivitis using a conjunctival allergen challenge test. Subjects were randomized into 3 groups (n = 87) to evaluate superiority to placebo (visits 4 to 6) and 2 groups (n = 86) to evaluate noninferiority to olopatadine (visit 7). At each visit, a single administration of the study medication was instilled at 15 minutes (visit 4), 4 hours (visit 5), 8 hours (visit 6), and 4 hours (visit 7) before the conjunctival allergen challenge test. Ocular itching and conjunctival hyperemia of allergic conjunctivitis were assessed after the conjunctival allergen challenge test.

RESULTS

For the primary end point, epinastine showed superiority to placebo for the inhibition of ocular itching and conjunctival hyperemia induced at 4 hours after the dose (equivalent to 4-times-daily dosing). For the secondary end points, epinastine significantly inhibited itching and conjunctival hyperemia induced at 15 minutes and 8 hours after the dose (equivalent to 2-times-daily dosing) compared with placebo. In addition, epinastine demonstrated noninferiority to olopatadine for ocular itching and conjunctival hyperemia. No adverse drug reactions or serious adverse events were reported throughout the study, indicating that epinastine has a good safety profile.

CONCLUSION

Epinastine is effective and safe for the treatment of allergic conjunctivitis.

TRIAL REGISTRATION

Clinicaltrials.gov identifier NCT01363700.

Emerging drugs for allergic conjunctivitis

INTRODUCTION

Allergic conjunctivitis (AC) is a very common disease, especially in association with allergic rhinitis but may also occur in isolated presentation. The treatment of AC has long been based on antihistamines, cromones and topical corticosteroids, but none of these drugs completely abolishes the clinical expression of AC.

AREAS COVERED

The development of new drugs for AC is analyzed highlighting the recent insights into the pathophysiological mechanisms of the disease. The major aim of development of drugs for AC is to have agents able to prevent the inflammatory effects of the interaction between the allergen and the specific IgE antibodies on mast cell surface. This may be obtained by blocking the effects of histamine (the main mediator of early allergic response) by H1-receptor antagonists, inhibiting the release of soluble factors able to recruit inflammatory cells (that sustain prolonged inflammation) by mast-cell stabilizers, inhibiting the effects of single mediators, inducing tolerance to the allergen by specific immunotherapy or even acting on factors related to activation and differentiation of T lymphocytes such as the toll-like receptors.

EXPERT OPINION

AC is an underestimated disease for which there is a search of more effective treatments. The availability of the drugs under current evaluation will allow more refined therapeutic strategies to apply according to the characteristics and the clinical severity of AC.

Comparative efficacy and bioequivalence of novel h1-antihistamine bepotastine salts (nicotinate and salicylate)

Bepotastine salts (nicotinate and salicylate) were investigated for their physicochemical properties to develop novel salt forms of bepotastine, bioequivalent to the bepotastine besilate-loaded tablet (Talion). These bepotastine salts of either nicotinate- or salicylate-loaded tablets were prepared by conventional wet granulation method, and dissolution profiles and pharmacokinetics in beagle dogs were compared to those of Talion. A novel bepotastine nicotinate has a higher solubility at varying pH levels (1.2, 4, or 6.8) than salicylate-loaded or besilate-loaded salt. In addition, those bepostastine salt forms (nicotinate and salicylate) are stable in heat, light, and water. Further, the novel nicotinate- and salicylate-loaded tablets showed similar dissolution rates to Talion in several selected dissolution media and were bioequivalent to Talion in beagle dogs in terms of area under the concentration-time curve (AUC) and maximum observed concentration (Cmax). A pharmacokinetic study performed in beagle dogs demonstrated that test and reference products were found to be bioequivalent in terms of safety, efficacy, and pharmacokinetic properties. These results suggest that bepostastine nicotinate and salicylate formulations are considered applicable candidates and are well tolerated versus the conventional bepostastine besilate formulation.

Bepotastine besilate for the treatment of pruritus

INTRODUCTION

Bepotastine besilate 1.5% is a newly approved second-generation topical antihistamine indicated for the pruritus associated with allergic conjunctivitis. In Japan, the oral formulation is approved to manage pruritus associated with allergic rhinitis and urticaria.

AREAS COVERED

Bepotastine is a piperidine derivative that antagonizes H1 receptors with high selectivity. It has been labeled a dual-acting or multiple-acting antiallergic medication, because it inhibits histamine at H1 receptors and stabilizes mast cells to prevent histamine release. Bepotastine may also have other immunoactive properties, such as inhibition of eosinophil migration, interleukin-5 (IL-5), leukotrienes (e.g., LTB4) and platelet-activating factor (PAF). Human clinical trials demonstrate the efficacy and safety of systemic and ophthalmic bepotastine for pruritus relief, limited penetration across the blood-brain-barrier and kinetics suitable for twice-daily administration.

EXPERT OPINION

Bepotastine besilate 1.5% ophthalmic solution is a safe and effective treatment option for allergic conjunctivitis associated pruritus. Side-effect profile is similar to other ocular antihistamine agents. Additional comparative-effectiveness studies would further advance its clinical use. Oral bepotastine is a safe and effective treatment option approved in Japan for allergic rhinitis, urticaria and pruritus associated with skin diseases.