Efficacy and safety of nedocromil sodium ophthalmic solution in the treatment of seasonal allergic conjunctivitis

Sustained Delivery of Olopatadine from Vitamin-E Loaded Contact Lenses

Purpose: Topical antihistamines, such as olopatadine hydrochloride, an H1 receptor antagonist, are commonly prescribed for treating allergic conjunctivitis. Drug delivery via eye drops has many deficiencies including a short residence time due to tear drainage via the nasolacrimal duct, which results in a low bioavailability and potential for side effects. These deficiencies could be mitigated by a drug-eluting contact lens such as the recently approved ACUVUE® THERAVISION™ WITH KETOTIFEN which is a daily disposable etafilcon, a drug-eluting contact lens with ketotifen (19 μg per lens). Here, we investigate the feasibility of designing a drug-eluting lens with sustained release of olopatadine for treating allergies using an extended wear lens. Methods: Nanobarrier depots composed of vitamin-E (VE) are formed through direct entrapment by ethanol-driven swelling. The drug-loaded lenses are characterized for transparency and water content. In vitro release is measured under sink conditions and fitted to a diffusion control release model to determine diffusivity and partition coefficient. Results: In vitro studies indicate that ACUVUE OASYS® and ACUVUE TruEye™ lenses loaded with ∼0.3 g of VE/g of hydrogel effectively prolong olopatadine dynamics by 7-fold and 375-fold, respectively. Incorporation of VE into the lenses retains visible light transmission and other properties. Conclusion: The VE incorporation in commercial lenses significantly increases the release duration offering the possibility of antiallergy extended wear lenses.

Group Comparative Trial of 2% Nedocromil Sodium with Placebo in the Treatment of Seasonal Allergic Conjunctivitis

A double blind group comparative trial comparing 2% nedocromil sodium with placebo in treating seasonal allergic conjunctivitis over a four week period is reported. Sixty-four patients were analysed. During the period of peak pollen challenge, statistically significant differences in favour of nedocromil sodium for itching and soreness were demonstrated. During a longer period of a less high pollen count, a significant difference in favour of nedocromil sodium was shown only for the symptom of soreness.

A review of non-pharmacological and pharmacological management of seasonal and perennial allergic conjunctivitis

Allergic eye disease encompasses a group of hypersensitivity disorders which primarily affect the conjunctiva and its prevalence is increasing. It is estimated to affect 8% of patients attending optometric practice but is poorly managed and rarely involves ophthalmic assessment. Seasonal allergic conjunctivitis (SAC) is the most common form of allergic eye disease (90%), followed by perennial allergic conjunctivitis (PAC; 5%). Both are type 1 IgE mediated hypersensitivity reactions where mast cells play an important role in pathophysiology. The signs and symptoms are similar but SAC occurs periodically whereas PAC occurs year round. Despite being a relatively mild condition, the effects on the quality of life can be profound and therefore they demand attention. Primary management of SAC and PAC involves avoidance strategies depending on the responsible allergen(s) to prevent the hypersensitivity reaction. Cooled tear supplements and cold compresses may help bring relief. Pharmacological agents may become necessary as it is not possible to completely avoid the allergen(s). There are a wide range of anti-allergic medications available, such as mast cell stabilisers, antihistamines and dual-action agents. Severe cases refractory to conventional treatment require anti-inflammatories, immunomodulators or immunotherapy. Additional qualifications are required to gain access to these medications, but entry-level optometrists must offer advice and supportive therapy. Based on current evidence, the efficacy of anti-allergic medications appears equivocal so prescribing should relate to patient preference, dosing and cost. More studies with standardised methodologies are necessary elicit the most effective anti-allergic medications but those with dual-actions are likely to be first line agents.

Vernal conjunctivitis

Vernal conjunctivitis is a bilateral, seasonal, external ocular inflammatory disease of unknown cause. Afflicted patients experience intense itching, tearing, photophobia, and mucous discharge, and usually demonstrate large cobblestone papillae on their superior tarsal conjunctiva and limbal conjunctiva. It primarily affects children, may be related to atopy, and has environmental and racial predilections. Although usually self-limited, vernal conjunctivitis can result in potentially blinding corneal complications. Treatment of chronic forms of ocular allergies may necessitate collaborative efforts between the ophthalmologist and the allergist or immunologist.

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.

Supplementation of fexofenadine therapy with nedocromil sodium 2% ophthalmic solution to treat ocular symptoms of seasonal allergic conjunctivitis

PURPOSE

Ocular symptoms are often under-treated in patients with allergic rhinoconjunctivitis. The efficacy of fexofenadine hydrochloride 60 mg capsules supplemented with nedocromil sodium 2% ophthalmic solution was evaluated to determine the optimal drug regimen for control of ocular allergic symptoms.

METHODS

In this 5-week, open-label, randomized, multicentre comparative study, 89 patients with documented ragweed pollen allergy received fexofenadine b.i.d. with nedocromil rescue, fexofenadine q.d. with nedocromil b.i.d., or fexofenadine rescue with nedocromil b.i.d. during the ragweed pollen season.

RESULTS

For all regimens, mean symptom severity scores for itching, burning, tearing, redness, grittiness, discharge, light sensitivity and swelling improved significantly (P < 0.003). Similarly, all groups experienced significant (P < 0.02) improvement in all clinical signs: erythema, oedema, discharge, conjunctival injection and conjunctivitis, as well as quality-of-life scores (P < 0.0001). All regimens reduced overall symptom severity scores after 5 min (P < 0.05) with relief persisting over 12 h (P < 0.03). Improvements in mean symptoms, signs and quality-of-life scores were similar among the treatment groups as were onset and duration of action even though patients in two of the three study arms were taking one-half or less of the recommended fexofenadine dosage. Patients and physicians judged the regimens containing lower fexofenadine dosages (with nedocromil b.i.d.) to be more effective overall than the regimen containing the highest fexo-fenadine dosage (with nedocromil as rescue only).

CONCLUSIONS

Supplementation of oral fexofenadine therapy with nedocromil sodium 2% ophthalmic solution relieves ocular symptoms of seasonal allergic rhinoconjunctivitis, allowing control of rhinal symptoms with half the recommended dosage of fexofenadine.

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.

Topical immunopharmacology of ocular allergies

PURPOSE OF REVIEW

To review the histamine-1 receptor antagonists, mast cell blockers and natural agents with such actions that can be used for the topical treatment of ocular allergies.

RECENT FINDINGS

Increasing evidence indicates that some histamine-1 receptor antagonists have additional actions to inhibit secretion of inflammatory mediators, especially cytokines, from ocular mast cells and other cell types. Emerging information suggests that such actions may be through regulation of intracellular calcium ion levels of NF-kappaB activation.

SUMMARY

A number of available drugs and natural non-prescription agents may have anti-histaminic and anti-inflammatory actions.

Ocular allergy guidelines: a practical treatment algorithm

The treatment of ocular allergy requires a better understanding of the spectrum of clinical disorders involving various components of the immune system, and of interactions at the conjunctival surface. The immune response focuses primarily on the different levels of activity of Th2 lymphocytes and various other immune cells associated with allergic disorders, including mast cells, eosinophils, fibroblasts, and epithelial and endothelial cells. Ocular allergic disorders include seasonal allergic conjunctivitis (SAC), perennial allergic conjunctivitis (PAC), vernal keratoconjunctivitis (VKC), giant papillary conjunctivitis (GPC) and atopic keratoconjunctivitis (AKC), which, through immunopathological and molecular immunological techniques, can all be better appreciated as being part of a larger spectrum of an atopic disease state. In SAC, pathological changes, such as increased mast-cell activation, the presence of migratory inflammatory cells, and early signs of cellular activation at the molecular level, are minimal. In PAC, these changes are more pronounced in line with the increased duration of allergenic stimulation. In more chronic forms of allergic conjunctivitis, such as VKC in children and AKC in adults, the following changes are evident: a persistent state of mast cell, eosinophil and lymphocyte activation; noted switching from connective-tissue to mucosal-type mast cells; increased involvement of corneal pathology; and follicular development and fibrosis. The treatment of acute and more chronic forms of allergic conjunctivitis has focused in the past on symptomatic relief of symptoms, but with a better understanding of the mechanisms involved we can now provide interventional therapeutic strategies and symptomatic relief. Our advances in the basic understanding of these conditions are providing the foundation for guidelines that improve the ocular health of patients with ocular allergies.

Update on ocular allergy treatment

Allergy affects > 15% of the world population with a higher prevalence of 30% in westernised industrialised countries, such as the US. Allergy commonly affects various target organs including the eyes, nose, sinuses, ears, lungs and skin. However, the ocular component may be the most common and initially the most prominent disabling feature. Some patients are affected for only a few weeks to months while others have symptoms that last throughout the year. The associated healthcare costs related to allergic conjunctivitis has been commonly nestled with allergic rhinitis and has been reported to be as high as US$5.9 billion in the US, with 25% (US$1.5 billion) of it related to medication use. The expenditures related to ocular prescription medication has only recently risen in the past decade from US$6 million in early 1990s to > US$200 million in the new millennium with a projected continuous expansion of 25% per year. This appears to be due to improved prescription medications and their clear benefit over the less efficacious over-the-counter products. The actual cost of the medications and their relative price increases over the past year have ranged from 0 - 49% with an average cost of < US$ day. The newer topical medications (multiple acting agents) are focusing on multiple actions that include an antihistaminic effect to provide an immediate relief and additional delayed effects to act on the mediators of the late phase reaction without steroid side effects (glaucoma, cataracts). The paradigm for the treatment of ocular allergy ranges from primary measures (avoidance measures, cold compresses and lubrication), to secondary measures (various combination of topical agents) and tertiary measures that would include topical steroids and immunotherapy. The increased interest in advancing ocular treatment will lead to the development of additional therapies, novel pharmacokinetic delivery systems and, thus, improved healthcare outcomes for patients with allergic conjunctivitis.

Nedocromil sodium ophthalmic solution 2% twice daily in patients with allergic conjunctivitis

In a multicenter, open-label evaluation, 1098 patients with ocular itching and a history of perennial or seasonal allergic conjunctivitis instilled one drop of nedocromil sodium 2% twice daily in each eye. Ocular symptoms, signs, and global improvement were assessed at baseline and 1 month; satisfaction scores, quality-of-life variables, and adverse events were also recorded. Significant improvements from baseline (P<.012) occurred in mean severity scores for itching, burning, stinging, watering, swelling, tired eyes, dryness, gritty sensation, eye pain, foreign-body sensation, and light sensitivity. Physicians reported significant reductions (P<.0001) in bulbar conjunctival redness and swelling. Two thirds of patients (634/954) and three fourths of physicians (710/954) reported at least 75% improvement in overall condition after 1 month. The most common adverse events were burning (2.7%) and unpleasant taste (1.4%); headache (1.2%) and adverse events leading to discontinuation (1.3%) were rare. Patients reported significant improvement (P<.001) in their ability to perform daily activities; 65% were more satisfied with nedocromil than with their typical medication. Physicians would prescribe nedocromil again to 80% of the patients. Nedocromil sodium 2% twice daily was effective and safe for the treatment of symptoms of allergic conjunctivitis, significantly improving quality of life and producing high rates of user and physician satisfaction.

Twice-daily and once-daily nedocromil sodium 2% ophthalmic solution for the treatment of seasonal allergic conjunctivitis

In this 8-week open-label, prospective study, 30 patients with grass pollen allergy and ocular itching instilled nedocromil sodium 2% ophthalmic solution twice daily for a 5-day baseline period, followed by once-daily dosing thereafter. Physicians assessed clinical signs after the twice-daily period and after weeks 1 and 3 of the once-daily period; patients rated ocular symptoms daily. Use of specified rescue medication was permitted. Symptom scores for ocular itching, stinging, redness, swelling, burning, tearing, and light sensitivity did not differ significantly between the dosage periods. Scores for erythema, edema, conjunctival injection, and the entire conjunctiva decreased slightly during once-daily administration; discharge scores were unchanged. Of the 20 patients who used rescue medication, only 5 increased their usage by more than two doses per week during the once-daily period. Eighty-three percent of patients were willing to continue the once-daily regimen during the next allergy season. Physicians rated overall control of seasonal allergic conjunctivitis with once-daily administration as "good" or "moderate" in 100% of the patients; 93% of patients applied those ratings themselves. Nedocromil sodium 2% ophthalmic solution instilled once daily maintains control of symptoms in patients who are established on a twice-daily regimen.

Nedocromil sodium in golfers with seasonal allergic conjunctivitis

To evaluate nedocromil sodium 2% ophthalmic solution for the treatment of seasonal allergic conjunctivitis, 24 golfers with documented ragweed-pollen allergy instilled eyedrops twice daily for 4 days prior to golf-course intervention and 15 minutes before playing a round of golf during peak ragweed season. Ocular symptoms were scored at baseline (7 days before golfing), prior to instillation on the day of golf, and 30 minutes, and 1, 4, 8, and 12 hours after tee-off. Physician assessment was performed prior to tee-off, before tee-off on the ninth hole, and at the end of the 18th hole. Itching, burning, grittiness, tearing, redness, and light sensitivity were significantly decreased after nedocromil administration, as were erythema, edema, conjunctival hyperemia, and overall findings in the conjunctiva. Symptom severity scores fell approximately 30 minutes after instillation, with improvements persisting 8 and 12 hours after treatment. Most patients (92%) rated the treatment moderately or completely effective, and 83% were willing to continue its use. Physician assessments of effectiveness agreed with those of the patients. In this open-label study, nedocromil sodium eyedrops relieved the ocular symptoms of seasonal allergic conjunctivitis for up to 12 hours, well beyond a usual round of golf.

Nedocromil sodium and levocabastine reduce the symptoms of conjunctival allergen challenge by different mechanisms

BACKGROUND

Nedocromil sodium and levocabastine are widely used for the treatment of ocular allergy, but their mechanisms of action are unclear.

OBJECTIVE

We sought to compare the efficacy and mechanisms of action of nedocromil sodium and levocabastine in reducing conjunctival symptoms after ocular allergen challenge.

METHODS

We performed a double-blind, placebo-controlled study in which 48 subjects were randomized to 3 groups to receive nedocromil sodium (2%), levocabastine (0.05%), or placebo eye drops twice daily for 2 weeks before ocular challenge with 10 microL of ryegrass extract. Symptoms and tear histamine and PGD(2) concentrations were determined before challenge and at 10, 20, 30, 60, 180, and 360 minutes after challenge. Bulbar biopsy specimens were taken at 6 and 24 hours after challenge to assess conjunctival inflammatory cell numbers, adhesion molecule expression, and mast cell-associated IL-4, IL-5, IL-6, IL-13, and TNF-alpha levels.

RESULTS

Both drugs significantly reduced total symptom scores (P <.05) at all times after challenge compared with placebo. Itching, hyperemia, and lacrimation were most affected. Nedocromil sodium treatment reduced tear concentrations of histamine (by 77%) and PGD(2) (by 70%) at 30 minutes after challenge (both P <.05). In biopsy specimens nedocromil sodium reduced the number of 3H4-positive mast cells (purportedly the secreted form of IL-4) by 49% at 6 hours and 59% at 24 hours (both P <.05). Levocabastine reduced intercellular adhesion molecule 1 expression by 52% at 6 hours and 45% at 24 hours (both P <.05).

CONCLUSION

Nedocromil sodium and levocabastine both reduced the conjunctival symptoms after ocular allergen challenge but appeared to work by different mechanisms. Nedocromil sodium reduced mast cell function, whereas levocabastine appeared to have primarily antihistaminic actions, although it also reduced the expression of intercellular adhesion molecule 1.

Allergic and immunologic disorders of the eye. Part II: ocular allergy

Allergy affects more than 15% of the world population, and some studies have shown that up 30% of the US population has some form of allergy. Most of these patients have various target organs for their allergies, and most have ocular involvement. The ocular component may be the most prominent and sometimes disabling feature of their allergy. Some are affected for only a few weeks to months, whereas others have symptoms that last throughout the year. The seasonal forms may present to clinical allergists, whereas the more chronic forms may present to ophthalmologists. Thus, in the second of this 2-part review series (Part I: Ocular Immunology appeared in the November issue of the Journal), an overview is provided of the spectrum of ocular allergy that ranges from acute seasonal allergic conjunctivitis to chronic variants of atopic keratoconjunctivitis. With a better understanding of the immunologic mechanisms, we now can develop better treatment approaches and design further research in intervention of allergic eye diseases.

Efficacy and acceptability of nedocromil sodium 2% and olopatadine hydrochloride 0.1% in perennial allergic conjunctivitis

In this 2-week, randomized, crossover study, ophthalmic solutions of nedocromil sodium 2% and olopatadine hydrochloride 0.1% were compared for effectiveness and acceptability in 28 patients with perennial allergic conjunctivitis and previous olopatadine experience. Patients received nedocromil twice daily or olopatadine twice daily for 1 week, then were crossed over to the alternate medication for 1 week. Outcome measures were patient satisfaction (questionnaire), severity of ocular symptoms (daily diary scores), clinical signs (physician assessments), quality of life (questionnaire), and global assessments of effectiveness. Both medications were well accepted. Of the 28 patients, 16 (57.1%) would request a nedocromil prescription, 10 (35.7%) an olopatadine prescription (P = .157); 22 patients (78.6%) would recommend nedocromil to other allergy sufferers, while 18 (64.3%) would recommend olopatadine (P = .480). Light sensitivity scores were significantly lower with nedocromil (P = .0125); other symptom scores were comparable between medications. Both drugs significantly (P < .01) and comparably decreased erythema, conjunctival injection, and overall conjunctival signs from baseline. Comparable improvement also occurred in quality-of-life scores. Both physicians and patients judged nedocromil and olopatadine to be similarly effective in preventing signs and symptoms. Nedocromil sodium 2% is an effective treatment for perennial allergic conjunctivitis. Patients receiving olopatadine can be switched to nedocromil with no loss in efficacy or satisfaction, but with a reduction in cost.

How to write about pollen

BACKGROUND

Clinicians and palynologists (pollen specialists) often have different ways of expressing the same thing when they write about pollen.

OBJECTIVE

This brief paper considers the confusing use of the word pollens that is frequently encountered in medical literature.

METHODS

Three common uses for the word pollens are considered citing examples from clinical literature. The problems associated with each case are explored.

RESULTS

Words and phrases that can serve as suitable alternatives to the word pollens are presented. The advantages of these alternatives are discussed.

CONCLUSION

The word pollens represents a vague usage that obscures the author's intended meaning. Consistent application of the suggested alternatives will enhance the transmission of key concepts in the medical literature.

A randomized, double-masked, placebo-controlled parallel study of loteprednol etabonate 0.2% in patients with seasonal allergic conjunctivitis

OBJECTIVE

To evaluate the effects of loteprednol etabonate (LE) 0.2% in reducing the signs and symptoms of seasonal allergic conjunctivitis.

DESIGN

Randomized, double-masked, placebo-controlled, parallel group multicenter study of 6 weeks duration.

PARTICIPANTS

A total of 135 patients with signs and symptoms of seasonal allergic conjunctivitis participated.

INTERVENTION

All patients received either LE 0.2% or placebo (vehicle) four times a day in both eyes for 42 days.

MAIN OUTCOME MEASURES

Bulbar conjunctival injection (primary sign) and itching (primary symptom) over the first 2 weeks of treatment was measured.

RESULTS

A reduction in severity was seen in both LE and placebo groups for bulbar conjunctival injection (1.5 vs. 1.0 units on a 0-3 scale) and itching (3.4 vs. 3.0 units on a 0-4 scale) over the first 2 weeks. The treatment effect by these measures was -0.5 and -0.4 units in favor of LE (P < or = 0.008). Resolution (i.e., the proportion of patients with signs or symptoms no longer present) at day 14 strongly favored LE-treated patients (36% and 15%; 58% and 38%, for injection and itching, respectively). Both treatments were well tolerated. One patient in each treatment group (1 of 67 and 1 of 68, respectively) had an elevation of intraocular pressure of 10 mmHg or greater during the 6 weeks of treatment.

CONCLUSIONS

Loteprednol etabonate 0.2% was more effective than placebo in the treatment of seasonal allergic conjunctivitis. Loteprednol etabonate 0.2% had a safety profile comparable to placebo.

Efficacy of nedocromil 2% versus fluorometholone 0.1%: a randomised, double masked trial comparing the effects on severe vernal keratoconjunctivitis

AIMS

To compare the efficacy of topical nedocromil 2% with fluorometholone 0.1% in vernal keratoconjunctivitis (VKC).

METHODS

In a double masked random design, 24 patients with severe vernal keratoconjunctivitis were placed at random on nedocromil 2% eye drops in one eye and fluorometholone 0.1% in the fellow eye. At the end of the 2 week treatment period, the patient crossed over the eye drops (if asymptomatic in one eye), or continued with nedocromil sodium in both eyes (if asymptomatic in both eyes). All patients were examined weekly and ocular surface temperature recorded for a period of 6 weeks.

RESULTS

Improvement in the watering, discharge, conjunctival hyperaemia, papillary hypertrophy, and Trantas' dots was noted in both groups, but overall fluorometholone was significantly more effective than nedocromil. Eyes treated with fluorometholone showed a significant decrease in ocular surface temperature compared with nedocromil treated eyes (p = 0.03).

CONCLUSIONS

Both nedocromil and fluorometholone were effective in ameliorating the signs and symptoms of vernal keratoconjunctivitis. No adverse effects were noted in the nedocromil group.

Expression of ICAM-1 and HLA-DR by human conjunctival epithelial cultured cells and modulation by nedocromil sodium

It is unclear whether conjunctival epithelial cells participate in the development of immune-mediated events. Using a previously reported in vitro system of human conjunctival epithelium, we determined whether conjunctival epithelial cells express two relevant markers in the antigenic presentation process. Moreover, the potential capability of nedocromil sodium, an antiallergic and antiinflammatory drug, to modulate such expression was investigated. Primary cultures of human conjunctival epithelium and Chang conjunctival cells, incubated with or without 100 U/ml IL-1beta and/or IFNgamma for 1, 3 or 6 h, were simultaneously exposed to 10(-5) M nedocromil sodium. The expression of the intercellular adhesion molecule-1 (ICAM-1) and the human leukocyte antigen-DR (HLA-DR) was determined immunocytochemically. Constitutive expression of ICAM-1 and HLA-DR was observed in primary cultures and Chang cells and was minimally affected by incubation with IL-1beta and/or IFNgamma. The addition of nedocromil sodium resulted in complete abolition of HLA-DR expression and a notable reduction in ICAM-1 expression in primary cultures and Chang cells. These results suggest that epithelial cells from human conjunctiva constitutively express ICAM-1 and HLA-DR in vitro and that such expression is downregulated by nedocromil sodium. This may indicate that conjunctival epithelial cells may be another target for this drug.

Evaluation of olopatadine, a new ophthalmic antiallergic agent with dual activity, using the conjunctival allergen challenge model

BACKGROUND

An ophthalmic antiallergic agent with selective H1 antihistaminic and mast cell stabilizing properties has been developed.

OBJECTIVES

To evaluate efficacy and safety, determine optimal concentration, and demonstrate onset and duration of action of this new drug, olopatadine.

METHODS

This was a placebo-controlled, randomized, double-masked, parallel-group, single-center study with five outpatient visits at least 7 days apart. Ninety-eight healthy, allergy-positive, subjects with a recent history of active allergic conjunctivitis not receiving current treatment participated. Conjunctival allergen challenge (CAC) tests were performed on visits 1 and 2 to identify an allergen and concentration that consistently elicited signs and symptoms of allergic conjunctivitis. On visits 3, 4, and 5, CAC was performed 27 minutes, 8 hours, and 6 hours, respectively, after instillation of one drop of olopatadine (0.01%, 0.05%, 0.1%, or 0.15%) in one eye and placebo in the other. Both eyes were scored for the intensity of itching and redness at 3, 10, and 20 minutes after the CAC.

RESULTS

All four concentrations of olopatadine were clinically and statistically superior to placebo in preventing ocular itching at all evaluations and preventing redness at most evaluations from immediately and 8 hours after drug administration. No drug-related adverse events were reported. The 0.1% concentration was found to be most effective.

CONCLUSIONS

The results indicate that olopatadine ophthalmic solution is safe and effective in the treatment of allergic conjunctivitis, with the 0.1% concentration of olopatadine being optimal. The rapid onset and at least 8 hour duration of action of olopatadine indicates that the drug can be used twice daily.

A controlled evaluation of the efficacy and safety of loteprednol etabonate in the prophylactic treatment of seasonal allergic conjunctivitis. Loteprednol Allergic Conjunctivitis Study Group

PURPOSE

To evaluate the efficacy and safety of loteprednol etabonate 0.5% as prophylactic treatment for the ocular signs and symptoms of seasonal allergic conjunctivitis.

METHODS

In this randomized, double-masked, placebo-controlled, parallel study, 293 adults with history of seasonal allergic conjunctivitis were treated with either loteprednol etabonate or vehicle (placebo) four times daily, beginning before the onset of the allergy season and continuing for 6 weeks. The primary efficacy measure was a primary composite score (sum of itching and bulbar conjunctival injection scores). Supportive efficacy measures were the investigator global assessment and a secondary composite score (sum of tearing, erythema, chemosis, and discomfort scores), all calculated during the 21-day peak pollen season.

RESULTS

The proportion of patients who never developed moderate or severe signs and symptoms of allergy during the peak pollen season in the loteprednol etabonate treatment group was greater than that in the placebo group. For the primary composite score, this efficacy criterion was reached by 94% of patients (136/145) in the loteprednol etabonate group and 78% of patients (111/143) in the placebo group (P = .001). The magnitude of effect was similar for the investigator global assessment (86% [118/138] vs 64% [87/137]; P < .001) and, although not statistically significant, the secondary composite score (77% [112/145] vs 68% [97/143]; P = .092). None of the loteprednol etabonate-treated patients had an intraocular pressure increase of 10 mm Hg or more, whereas two placebo patients did.

CONCLUSIONS

Loteprednol etabonate is generally effective in prophylaxis of seasonal allergic conjunctivitis and has an acceptable safety profile.

Efficacy of nedocromil sodium and cromolyn sodium in an experimental model of ocular allergy

BACKGROUND

Because ocular allergic disorders are important in terms of frequency and severity, there is a constant search for new topical antiallergic drugs. Nedocromil sodium has recently been introduced as a potential substitute for the mast cell stabilizer cromolyn sodium.

OBJECTIVE

We compared the efficacy of topical 2% nedocromil sodium to that of 2% cromolyn sodium in treatment of the early-phase reaction of an experimental model of allergic conjunctivitis.

METHODS

Guinea pigs were challenged topically with egg albumin 14 days after systemic immunization. Fifteen minutes before, immediately prior to, and 15 minutes after topical challenge, the animals received either 2% nedocromil sodium or 2% cromolyn sodium topically in one eye and phosphate buffered saline (PBS) in the other eye. Antigen-induced increase in vascular permeability was measured by the extravasation of intravenously injected Evans blue dye. Animals that were immunized and topically challenged but did not receive Evans blue were used for histologic studies.

RESULTS

Evans blue extravasation from ocular tissues significantly decreased in drug-treated eyes compared with PBS-treated eyes (P < .01). Further, the cellular infiltrate (mast cells, eosinophils, and neutrophils) in the substantia propria of the conjunctiva was markedly reduced in the drug-treated eyes. No significant difference was observed between the nedocromil sodium- or cromolyn sodium-treated eyes.

CONCLUSIONS

Topical 2% nedocromil sodium reduces the early-phase reaction of the allergic response as effectively as 2% sodium cromoglycate in a guinea pig model of ocular anaphylaxis.

The pathophysiology of ocular allergy: current thinking

Seasonal allergic conjunctivitis is the only ocular disease to involve solely Type-1 hypersensitivity, the other main forms of ocular allergy--perennial allergic conjunctivitis, vernal and atopic keratoconjunctivitis and giant papillary conjunctivitis--each having a more complex immunological basis and a chronic inflammatory component. Involvement of secondary inflammatory cells, particularly eosinophils, in addition to the mast cells resident in the conjunctival substantia propria, can lead to more serious corneal damage with vision-threatening potential. Thoughtful management of allergic conjunctivitis is needed in order to control the ocular inflammation without incurring steroid-induced side-effects, and patient education is also an important factor in maintaining optimal allergen avoidance, especially in the more severe and chronic cases. Laboratory models can be helpful in assessing the potential of new drugs, and SWR mice (topically sensitised and challenged with short ragweed) show clinical signs of allergic conjunctivitis, together with mast cell and eosinophil involvement, remarkably similar to the human pathophysiology. The antiinflammatory activity of both steroids and nedocromil sodium observed in this animal model supports therapeutic evidence of the usefulness of second-generation mast cell stabilising drugs in the treatment of ocular allergy.

Nedocromil sodium 2% eye drops for twice-daily treatment of seasonal allergic conjunctivitis: a Swedish multicentre placebo-controlled study in children allergic to birch pollen

This was a multicentre, double-blind, randomized group comparative study in which 77 children, aged 6-16 years, received 2% nedocromil sodium eye drops and 72 received placebo, one drop into each eye twice daily. The treatment period was 4 weeks, covering the peak birch pollen season. Prior to the start of the season, patients who had attended the clinic the previous 2 years because of seasonal allergic conjunctivitis (SAC) to birch pollen, entered a one week baseline period during which symptoms were assessed, dairy cards completed, and routine sampling of blood and urine carried out. The double-blind treatment period then commenced at the onset of the birch pollen season. Patients/parents kept daily diary record cards of eye symptom severity and concomitant therapy. Conjunctivitis was mild in both treatment groups but nedocromil sodium was more effective than placebo in controlling symptoms. During the 2-3 weeks of peak pollen counts, this therapeutic effect was statistically significant for itching (P < 0.01), watering (P < 0.05) and total symptom score (P < 0.01), but was not significant for grittiness (P = 0.08) or redness (P = 0.06). Global opinions of efficacy showed no difference between treatments, due to a high placebo effect (however, the diary card data indicated a significant improvement with nedocromil sodium). We therefore conclude that nedocromil sodium 2% eye drops, administered twice daily, is an effective treatment for SAC in children.

Nedocromil sodium and astemizole, alone or combined, in the treatment of seasonal allergic conjunctivitis. A multicentre double blind clinical trial

Two hundred and seven patients with active symptoms of allergic conjunctivitis were studied in a four-week multicentre double blind, double dummy, clinical trial comparing efficacy and safety of nedocromil sodium eye drops with oral astemizole, placebo, and the combined active treatments. Clinical signs were evaluated by clinicians after 1, 2 and 4 weeks, while symptoms were recorded by patients on daily diary cards. Overall opinions were recorded at the end of treatment. Nedocromil sodium eye drops and astemizole, alone or combined, significantly reduced ocular symptoms when compared to placebo (diary card total symptom score and patients' opinion). In the clinicians' opinion nedocromil sodium alone or combined (but not astemizole alone) significantly decreased ocular symptoms when compared to placebo. All treatments were safe and well tolerated, drowsiness being the most frequent side effect observed in patients treated with astemizole. These results indicate the effectiveness of nedocromil sodium eye drops in the treatment of seasonal allergic conjunctivitis.

Nedocromil sodium and astemizole, alone or combined, for treatment of seasonal allergic conjunctivitis (SAC)

SAC is caused by allergen interaction with IgE antibody on conjunctival mast cells, leading to local release of vasoactive inflammatory mediators such as histamine. Nedocromil sodium both stabilizes mast cells and has antiinflammatory activity against other cells involved in allergic inflammation. Astemizole is a second generation orally-active H(1)-receptor antagonist with reduced CNS effects such as drowsiness. This multicentre, double blind, double dummy trial compared efficacy and safety of qid 2% nedocromil sodium eye drops with once daily 10 mg oral astemizole, placebo, and combined active treatments for a four-week period. SAC patients (n=207, aged 6-70 years) recorded their symptoms each day on diary cards. Signs and symptoms were also evaluated by clinicians after one, two and four weeks and overall opinions were recorded at the end of treatment. Nedocromil sodium eye drops and astemizole, alone or combined, significantly reduced ocular symptoms compared to placebo (for diary card total symptom score and patients' opinion). Clinicians' opinion showed significantly decreased symptoms with nedocromil sodium, alone or combined, but not with astemizole alone. All treatments were well tolerated, with drowsiness the most frequent side effect observed in patients treated with astemizole. These results demonstrate the effectiveness of nedocromil sodium eye drops in the treatment of SAC.

Treatment of vernal keratoconjunctivitis a double-masked study

Thirty-one children aged five to 14 years with severe vernal keratoconjunctivitis (VKC) were enrolled in a double-masked study evaluating the efficacy of three ophthalmic preparations: cromolyn sodium (Opticrom) 2%, artificial tears and fluorometholone 0.1% (FML). These drugs were coded respectively as A, B, C, and dispensed in similar bottles. Both eyes were treated, and drug assignment was made at random. Objective assessment of the disease activity was done under slit lamp by two ophthalmologists according to a five-point scale. The results were tabulated and the chi-square test performed. Decoding of the drugs was done only after completion of the statistical analysis. FML was found effective with a statistically significant difference from the other two drugs, both after the first week on the initially assigned treatment (p = 0.05) and on completion of the treatment period according to protocol (p = 0.005). Although several patients improved under cromolyn sodium, there was no statistically significant difference between cromolyn sodium 2% and artificial tears. All the preparations were well tolerated. One patient developed bilateral allergic blepharitis when treated with FML during the study. Another patient who responded well to FML developed posterior subcapsular cataract while continuing treatment with corticosteroids a few months after completion of the study.