The effects of topical nonsteroidal anti-inflammatory drugs on adenoviral replication

Antiviral Drugs in Adenovirus-Induced Keratoconjunctivitis

Human adenovirus (HAdV) is one of the most common causes of conjunctivitis worldwide. Depending on specific serotypes and other factors, it can lead to several ocular manifestations, ranging from isolated, self-limited disease to epidemic and potentially sight-threatening keratoconjunctivitis. To date, no antiviral agent against ocular adenovirus has been licensed, and its management is still based on hygienic and supportive measures alone. In this review, a literature search up to August 2021 was performed to find peer-reviewed articles, with the primary aim to investigate drugs or other compounds with any antiviral activity against adenovirus. Finally, we included 70 articles, consisting of both in vitro, and in vivo studies on animal models and clinical trials of any phase, as well as a case-report, and analyzed each compound separately. Many antiviral agents proved to be effective on in vivo and in vitro studies on animal models, and in pre-clinical trials, but lacked reliability in large, controlled clinical investigations. The design of such studies, though, presented several hurdles, due to the nature and the specific characteristics of adenovirus-induced ocular diseases. Nevertheless, some promising compounds are currently under study, and further investigations are needed to prove their efficacy in the management of adenovirus conjunctivitis.

Povidone iodine for the treatment of adenoviral conjunctivitis

Adenoviral conjunctivitis is the most common cause of ocular viral infection in the world, but currently has no approved therapeutic treatments. The antiseptic povidone-iodine (PVP-I) has been used as an off-label treatment for the condition, but high-quality evidence for its use is limited. This paper aims to review the literature surrounding the use of PVP-I in the management of adenoviral conjunctivitis. Unfortunately, treatment regimens, inclusion criteria, outcome measures, and review periods vary widely between studies, making direct comparisons between outcomes difficult. The majority of studies investigate daily instillation of 0.4 to 2.0% PVP-I rather than one-time instillation of PVP-I as has been used anecdotally in practice. In addition, only one treatment arm investigates daily PVP-I alone, with no significant difference in the duration of disease or clinical outcome compared to placebo. All other treatment arms investigate PVP-I in combination with dexamethasone which generally improve outcomes. Tolerability of PVP-I is generally good for low concentrations <1.0%, but efficacy of treatment is generally reported to be concentration dependent. Future research should investigate the optimal concentration, dosing regimen and role of each agent in combination treatment and aim to use laboratory techniques to improve diagnosis and provide quantifiable outcomes.

The Treatment Models for Adenoviral Keratoconjunctivitis in the Childhood Population

PURPOSE

To examine the effects of treatments performed on children with adenoviral conjunctivitis.

METHODS

50 children with Adenoviral keratoconjunctivitis (AK) were evaluated. Patients were divided into four groups according to the medical treatment agents that were used previously. AK symptoms were clinically scored and analyzed. The diagnosis of all children was confirmed by an in-office lateral flow immunoassay.

RESULTS

Fifty patients with AK were included in the study. 24 (48%) were female and 26 (52%) were male. The mean age was 12.88 ± 2.66 (8-17). In PVP-I groups clinical findings shows faster improvement than other groups (p < .05).

CONCLUSIONS

Conjunctival irrigation with 2.5% PVP-I is very effective for the treatment of adenoviral conjunctivitis in childhood. Ganciclovir ophthalmic gel 0.15% increases the effect of 2.5% PVP-I on AK, but this was not statistically significant.

Management of Adenoviral Keratoconjunctivitis: Challenges and Solutions

Human adenovirus (HAdV) is the most common cause of infectious conjunctivitis, accounting for up to 75% of all conjunctivitis cases and affecting people of all ages and demographics. In addition to ocular complications, it can cause systemic infections in the form of gastroenteritis, respiratory disease, and dissemination in immunocompromised individuals. HAdV causes lytic infection of the mucoepithelial cells of the conjunctiva and cornea, as well as latent infection of lymphoid and adenoid cells. Epidemic keratoconjunctivitis (EKC) is the most severe ocular manifestation of HAdV infection, in which the presence of subepithelial infiltrates (SEIs) in the cornea is a hallmark feature of corneal involvement. SEIs have the tendency to recur and may lead to long-term visual disability. HAdV persistence and dissemination are linked to sporadic outbreaks of adenoviral keratoconjunctivitis. There is no FDA-approved antiviral for treating adenoviral keratoconjunctivitis, and as such, solutions should be proffered to handle the challenges associated with viral persistence and dissemination. Several treatment modalities have been investigated, both systemically and locally, to not only mitigate symptoms but reduce the course of the infection and prevent the risk of long-term complications. These options include systemic and topical antivirals, in-office povidone-iodine irrigation (PVI), immunoglobulin-based therapy, anti-inflammatory therapy, and immunotherapy. More recently, combination PVI/dexamethasone ophthalmic formulations have shown favorable outcomes and were well tolerated in clinical trials for the treatment of EKC. Possible, future treatment considerations include sialic acid analogs, cold atmospheric plasma, N-chlorotaurine, and benzalkonium chloride. Continued investigation and evaluation of treatment are warranted to reduce the economic burden and potential long-term visual debilitation in affected patients. This review will focus on how persistence and dissemination of HAdV pose a significant challenge to the management of adenoviral keratoconjunctivitis. Furthermore, current and future trends in prophylactic and therapeutic modalities for adenoviral keratoconjunctivitis will be discussed.

Mystery eye: Human adenovirus and the enigma of epidemic keratoconjunctivitis

Known to occur in widespread outbreaks, epidemic keratoconjunctivitis (EKC) is a severe ocular surface infection with a strong historical association with human adenovirus (HAdV). While the conjunctival manifestations can vary from mild follicular conjunctivitis to hyper-acute, exudative conjunctivitis with formation of conjunctival membranes, EKC is distinct as the only form of adenovirus conjunctivitis in which the cornea is also involved, likely due to the specific corneal epithelial tropism of its causative viral agents. The initial development of a punctate or geographic epithelial keratitis may herald the later formation of stromal keratitis, and manifest as subepithelial infiltrates which often persist or recur for months to years after the acute infection has resolved. The chronic keratitis in EKC is associated with foreign body sensation, photophobia, glare, and reduced vision. However, over a century since the first clinical descriptions of EKC, and over 60 years since the first causative agent, human adenovirus type 8, was identified, our understanding of this disorder remains limited. This is underscored by a current lack of effective diagnostic tools and treatments. In part, stasis in our knowledge base has been encouraged by the continued acceptance, and indeed propagation of, inaccurate paradigms pertaining to disease etiology and pathogenesis, particularly with regard to mechanisms of innate and adaptive immunity within the cornea. Owing to its often persistent and medically refractory visual sequelae, reconsideration of key aspects of EKC disease biology is warranted to identify new treatment targets to curb its worldwide socioeconomic burden.

Disparate Entry of Adenoviruses Dictates Differential Innate Immune Responses on the Ocular Surface

Human adenovirus infection of the ocular surface is associated with severe keratoconjunctivitis and the formation of subepithelial corneal infiltrates, which may persist and impair vision for months to years following infection. Long term pathology persists well beyond the resolution of viral replication, indicating that the prolonged immune response is not virus-mediated. However, it is not clear how these responses are sustained or even initiated following infection. This review discusses recent work from our laboratory and others which demonstrates different entry pathways specific to both adenovirus and cell type. These findings suggest that adenoviruses may stimulate specific pattern recognition receptors in an entry/trafficking-dependent manner, leading to distinct immune responses dependent on the virus/cell type combination. Additional work is needed to understand the specific connections between adenoviral entry and the stimulation of innate immune responses by the various cell types present on the ocular surface.

Ganciclovir ophthalmic gel treatment shortens the recovery time and prevents complications in the adenoviral eye infection

The purpose of this study was to determine the effectiveness of ganciclovir ophthalmic gel (GOG) in the treatment of adenoviral eye infection (AEI) by looking at the effect of the drug on shortening recovery time, preventing transmission, reducing sequelae, and on complications such as corneal infiltrates and conjunctival pseudomembranes. 200 patients' examination records were evaluated retrospectively. Patients who were within the first 3 days of AEI were divided into two groups: Group 1 with 100 patients who used artificial tears as treatment, and Group 2 with 100 patients who used GOG plus artificial tears (GAT). All patients underwent an eye examination by the same ophthalmologist on the 1st, 5th, 10th, and 15th day after treatment. Using the examination records, variables were compared using SPSS 22.0. There was a statistically significant difference between Groups 1 and 2. Group 2 showed better and faster response to treatment. There was less transmission to the contralateral eye and environment, and less formation of corneal subepithelial infiltrate and conjunctival pseudomembrane in Group 2. Only three patients in Group 2 had corneal involvement. A comparison of each group pre-treatment and during treatment revealed improved signs and symptoms in Group 2 (p < 0.005). The study showed a trend toward more rapid improvement, less corneal and conjunctival involvement, and less transmission to the contralateral eye and environment in the GAT group. These results need to be confirmed by additional studies.

Evaluation of the impact of persistent subepithelial corneal infiltrations on the visual performance and corneal optical quality after epidemic keratoconjunctivitis

PURPOSE

Aim was to measure the effect of persistent subepithelial corneal infiltrates (SEIs) after epidemic keratoconjunctivitis (EKC) on visual performance and corneal optical quality.

METHODS

We examined 53 patients divided into two groups. Patients with previous EKC constituted the study group (Group 1, n: 27). Healthy age matched subjects constituted the control group (Group 2, n: 26). Study group was subdivided into eyes with SEI (Group 1A, 40 eyes) and healthy fellow eyes (Group 1B, 14 eyes). Patients were submitted to a complete examination including high- and low-contrast visual acuities (HCVA, LCVA), corneal topography and aberrometry.

RESULTS

The mean interval between epidemic conjunctivitis and examination was 7.25 ± 5.63 months. Mean number of corneal infiltrates was 17.30 ± 14.38. The mean HCVA and LCVA were significantly lower in the eyes with SEI than fellow eyes and control group (p = 0.001). LCVA value was also worse in the fellow eyes when compared to control (p = 0.048). Corneal topography values were significantly higher in the eyes with SEI from both fellow eyes and control group. During corneal aberrometry, the mean root mean square value of spheric aberration, irregular astigmatism and total aberration were significantly higher in SEI group when compared to fellow eyes and control group (p < 0.05). Total aberrations were higher than control subjects in the fellow eyes. Trefoil aberration was higher in SEI group only when compared to control subjects, while there was no significant difference in coma aberration values between the groups (p > 0.05).

CONCLUSION

Results of this study suggested that visual performance is compromised in patients with EKC by aberrations and changes in topographic variables.

Topical 0.03% tacrolimus for subepithelial infiltrates secondary to adenoviral keratoconjunctivitis

OBJECTIVE

To determine the safety and efficacy of topical 0.03% tacrolimus ointment treatment for subepithelial corneal infiltrates (SEIs).

METHODS

This prospective non-controlled interventional case series included patients with SEIs who had been previously treated with topical corticosteroids with either no improvement or the medication being withdrawn due to associated intraocular pressure (IOP) elevation. The patients were treated with 0.03% tacrolimus ointment twice daily for 22 weeks (including a 1-month washout). The objective data were best-corrected Snellen visual acuity (BCVA), IOP, and full ocular examination results, including SEI severity and the Schirmer test. The subjective data were the patients' responses to a questionnaire at all follow-up visits.

RESULTS

The patients consisted of five males (45%) and six females (55%) (mean age 50 ± 11 years) who were followed up for an average of 22 weeks. The mean BCVA (logarithm of the minimum angle of resolution [logMAR]) before and after treatment was 0.34 ± 0.09 and 0.08 ± 0.04 respectively (p = 0.042). All the patients evidenced significant objective clinical improvement, and none had a severe degree of SEI at the end of the treatment. The patients reported considerable reduction in the severity of their symptoms (foreign body sensation, glare, etc.). Three patients were excluded due to side-effects (one had severe dizziness and discomfort), and their data were excluded from the study.

CONCLUSION

Topical tacrolimus 0.03% is a safe and effective alternative treatment in patients with SEIs who do not respond to other treatment modalities or have untoward side-effects from topical steroids.

Adenoviral keratoconjunctivitis: an update

The objective of this review is to describe the clinical and epidemiological characteristics of adenoviral conjunctivitis, as well as to present a practical update on its diagnosis, treatment and prophylaxis. There are two well-defined adenoviral keratoconjunctivitis clinical syndromes: epidemic keratoconjunctivitis and pharyngoconjunctival fever, which are caused by different adenovirus serotypes. The exact incidence of adenoviral conjunctivitis is unknown. However, cases are more frequent during warmer months. Contagion is possible through direct contact or fomites and the virus is extremely resistant to different physical and chemical agents. The symptomatology of conjunctival infection is similar to any other conjunctivitis, with a higher incidence of pseudomembranes. In the cornea, adenoviral infection may lead to keratitis nummularis. Diagnosis is mainly clinical, but its etiology can be confirmed using cell cultures, polymerase chain reaction or immunochromatography. Multiple treatments have been tried for this disease, but none of them seem to be completely effective. Prevention is the most reliable way to control this contagious infection.

Cyclosporine a 0.05% eye drops for the treatment of subepithelial infiltrates after epidemic keratoconjunctivitis

BACKGROUND

To evaluate the treatment with topical 0.05% cyclosporine A (CsA) in patients with subepithelial corneal infiltrates (SEI).

METHODS

We reviewed 16 patients (22 eyes) before and after the treatment with 0.05% CsA eye drops. All patients had been treated previously with topical corticosteroids without any improvement and also they had to stop the medication secondary to intraocular pressure elevation. The objective data recorded included best-corrected visual acuity (BCVA), evaluation of corneal subepithelial infiltrate scores (CSIS), intraocular pressure (IOP) prior to treatment and the last follow-up visit.

RESULTS

Six males (37.5%) and 10 females (62.5%), mean age of 35.2 ± 16.6 years, were included. The patients' average topical CsA use duration was 5.1 ± 3.5 months (1 - 13 months). The average follow up time of the patients was 9.2 ± 4.7 months (4 - 22 months). One patient, although he didn't have a 0 scale of SCIS, did not show up for follow up examinations after six months. The mean BCVA (logarithm of the minimum angle of resolution) before and after the treatment were 0.15 ± 0.15 and 0.07 ± 0.07 respectively, CSIS 1.68 ± 0.89 and 0.23 ± 0.53 respectively, IOP 18.50 ± 3.82 and 16.86 ± 2.76 mmHg respectively. There were statistically significant improvements in BCVA (p=0.002), reduction of CSIS (p=0.002) and reduction of IOP (p<0.001) prior to treatment and the last follow-up visit. 18 eyes (81.9%) showed clinical improvement and 4 (18.1%) had decreased SEI which did not fully disappear during the treatment period. The eyes which reached CSIS score 0 (18 eyes) were treated with CsA for 1 - 13 months; while the eyes which had clinical improvement but had not CSIS score 0 (4 eyes) were decided to discontinue of CsA treatment in last follow-up visit. There were recurrences in 2 eyes 3 months after the treatment. Patients reported reduction in the severity of symptoms after the treatment. Most of the patients reported no foreign body sensation, glare, or other side effects with topical CsA treatment. Overall, patients noted an improvement in vision and satisfaction with topical 0.05% CsA treatment.

CONCLUSIONS

Topical 0.05% CsA is a safe and effective alternative treatment in patients with SEI who do not respond to other treatment modalities or have undesired side effects from topical steroids.

Treatment of epidemic keratoconjunctivitis with 2% povidone-iodine: a pilot study

PURPOSE

The purpose of this study was to analyze the outcome of treating epidemic keratoconjunctivitis (EKC) with 2% povidone-iodine (PVP-I) solution.

METHODS

A prospective, interventional, uncontrolled study was performed in participants diagnosed with EKC. PVP-I was applied to the affected eyes 4 times a day for a week. Participants were informed about transient eye stinging and discoloration after application. Drug discontinuation was allowed for early recovery or encountering any adverse effects. Data collection included history, symptoms, and signs at the initial presentation and at 1 week. Main outcomes were the recovery rate within a week of treatment and drug tolerability.

RESULTS

Of 172 enrolled, 61 participants completed the study. EKC occurred bilaterally in 40 participants (66%). Single eye from each participant was included for analysis. The mean (standard deviation) time elapsed before treatment was 2.1 (1.46) days. The recovery rate within a week of treatment was 77% (95% confidence interval, 65.1-85.8). Twenty-eight participants (45.9%) recovered within a week after the onset. Application of PVP-I was sustained until recovery or completing a 7-day trial in 78.7%. No severe ocular or systemic adverse effects have been reported related to this treatment.

CONCLUSIONS

Ocular application of 2% PVP-I was tolerable. This measure successfully relieved ocular discomfort from EKC in 3 quarters of the study group within a week. A randomized, controlled trial is required to verify the benefit of this measure.

Treatment of viral conjunctivitis with antiviral drugs

Viral conjunctivitis is one of the most common disorders observed in ophthalmic emergency departments, yet no established treatment exists. Lately, antiviral medications have been introduced into clinical practice; however, a systematic review focusing on their use and effectiveness in the treatment of viral conjunctivitis has not been previously reported. We systemically reviewed the literature to identify studies where antiviral drugs were used to treat viral conjunctivitis. Currently, aciclovir, trifluridine and valaciclovir are commonly used as antiviral agents to treat herpesvirus infections. Cidofovir has been used successfully to treat some cases of adenoviral conjunctivitis, although toxicity has also been reported. The use of other medications, such as idoxuridine, has been minimized in clinical practice due to their high toxicity. Interestingly, most of the antiviral drugs developed are used to treat herpesvirus infections, while less progress has been made in the field of adenoviral infections. For other viral causes of conjunctivitis, no effective remedy is currently available, and treatment focuses on the relief of symptoms. Caution should be exercised when coadministering other pharmacological agents, such as corticosteroids, because of emerging adverse effects.

Diclofenac-loaded Eudragit S100 nanosuspension for ophthalmic delivery

In this study, diclofenac-loaded Eudragit S100-based nanosuspension was prepared by nanoprecipitation method and characterised for particle size, morphology, in vitro release, and for its in vivo ocular anti-inflammatory activity. The diclofenac-loaded Eudragit S100 nanosuspension was found to have a particle size of 172 nm, polydispersibility index of 0.14 and zeta potential of -23.7 +/- 6.07 mV, indicating that the nanosuspension is fairly stable. The nanosuspended particles were found to be spherical in shape. The nanosuspension was found to provide a sustained in vitro release, following the Higuchi square-root release kinetics. The results indicated that the nanosuspension released the drug by combination of dissolution and diffusion. The in vivo evaluation of nanosuspension in PGE(2)-induced ocular inflammation in rabbit model revealed a significantly (p  <  0.05) higher inhibition of PGE(2)-induced polymorphonuclear leukocytes migration and lid-closure scores as compared with the aqueous solution of diclofenac.

Topical treatment with 1% cyclosporine for subepithelial infiltrates secondary to adenoviral keratoconjunctivitis

PURPOSE

To evaluate the treatment with topical 1% cyclosporine A (CsA) in patients with subepithelial corneal infiltrates (SEIs).

METHODS

We retrospectively reviewed the records of 9 patients (12 eyes) before and after the treatment with CsA 1% eyedrops twice daily. All patients had been treated with topical corticosteroids previously without improvement or had to stop the medication secondary to intraocular pressure elevation. The objective data recorded included best-corrected Snellen visual acuity, intraocular pressure, number of medications in use, and evaluation of severity of SEIs (improved, stable, or worse). For their subjective evaluation, patients were asked to complete a questionnaire based on the last follow-up visit.

RESULTS

Five males (56%) and 4 females (44%), mean age of 47 +/- 13 years, were included. Mean follow-up on CsA was 13 +/- 7 months. The mean best-corrected Snellen visual acuity (logarithm of the minimum angle of resolution) before and after treatment was 0.42 +/- 0.40 and 21 +/- 0.28, respectively, with no statistically significant improvement. There was statistically significant reduction in the number of medications before and after treatment from 1.88 +/- 1.05 to 1.22 +/- 0.44, respectively (P = 0.049). Six patients (66%) showed clinical improvement, and 3 (34%) were stable during the treatment period. Patients reported statistically significant reduction in the severity of symptoms before and after the treatment. Most of the patients reported no foreign body sensation, glare, or other side effects with topical CsA treatment. Overall, patients noted an improvement in vision and satisfaction with CsA treatment.

CONCLUSIONS

Topical CsA 1% is a safe and effective alternative treatment in patients with SEIs who do not respond to other treatment modalities or have unwanted side effects from topical steroids.

Nonsteroidal anti-inflammatory drugs in ophthalmology

Nonsteroidal anti-inflammatory drugs (NSAIDs) are increasingly employed in ophthalmology to reduce miosis and inflammation, manage scleritis, and prevent and treat cystoid macular edema associated with cataract surgery. In addition, they may decrease postoperative pain and photophobia associated with refractive surgery and may reduce the itching associated with allergic conjunctivitis. In recent years, the U.S. Food and Drug Administration has approved new topical NSAIDs, and previously approved NSAIDs have been reformulated. These additions and changes result in different pharmacokinetics and dosing intervals, which may offer therapeutic advantages. For example, therapeutic effects on diabetic retinopathy and age-related macular degeneration may now be achievable. We provide an updated review on NSAIDs and a summary of their current uses in ophthalmology with attention to potential future applications.

In vitro corneal permeation of diclofenac from oil drops

In vitro transcorneal permeation of diclofenac from oil drops was studied using freshly excised goat cornea. The maximum apparent corneal permeability coefficient (Papp) was obtained with 0.2% (w/v) diclofenac drops in sesame oil followed by safflower oil, while formulation in castor oil provided minimal Papp. The addition of benzyl alcohol, a preservative, in oil drops, increased the Papp value of diclofenac. Partition experiments indicated increased partitioning of diclofenac in the aqueous phase in the presence of benzyl alcohol, and the same could be responsible for the benzyl alcohol-induced increase in Papp. The solubility of diclofenac was higher in castor, arachis, and sunflower oil. But drug permeation from 0.5-1.0% (w/v) diclofenac drops in castor oil or 0.5% (w/v) drops in arachis /sunflower oil was less than that observed with 0.2% (w/v) drops in sesame oil. Thus diclofenac 0.2% (w/v) drops in sesame oil containing 0.5% (v/v) benzyl alcohol provides maximum Papp. The formulation increased corneal hydration indicating corneal damage. Since corneal hydration is less than 83% the damage appears to be reversible. The saturation solubility of diclofenac in sesame oil at 4 degrees C is 0.33% (w/v). Hence diclofenac 0.2% (w/v) solution in sesame oil will not precipitate at 4 degrees C and therefore the chances of crystallization of diclofenac from the formulation due to climatic change leading to physical instability appear to be remote.

Efficacy of topical immunoglobulins against experimental adenoviral ocular infection

PURPOSE

Presently, there is no U.S. Federal Drug Administration (FDA)-approved antiviral therapy for the treatment of adenoviral (Ad) ocular infections. The goal of the present study was to determine the antiviral efficacy of human immunoglobulin (Ig), a preparation of highly purified and concentrated immunoglobulin (IgG) antibodies isolated from a large pool of human plasma donors, in vitro and on acute Ad replication in the Ad5 New Zealand White (NZW) rabbit ocular model.

METHODS

The antiviral activity of human Ig against multiple wild-type and human ocular isolates of adenovirus serotypes was investigated in vitro by using neutralizing assays in different human epithelial cell lines. In vivo bilateral topical ocular toxicity and antiviral efficacy were evaluated with established Ad5/NZW rabbit ocular models. In vivo Ig antiviral results were compared with those obtained with topical 0.5% cidofovir and saline.

RESULTS

In three different epithelial cell lines, <or=6.25 mg/mL of the Ig neutralized several wild-type adenoviral serotypes that cause ocular infections. A dose of <or=10 mg/mL neutralized 88% of ocular isolates of the adenovirus serotypes. After treatment of infected animals, adenovirus-positive cultures per total cultures (days 1-14; P = 0.021), the duration of Ad5 shedding, (P = 0.008), and the mean combined ocular viral titer during the early (days 1-5; P = 0.0001) and the late (days 7-14; P = 0.013) phases of infection were significantly lower in Ig-treated animals than in saline-treated animals and were similar to those in cidofovir-treated animals.

CONCLUSIONS

Ig demonstrated antiviral properties against multiple adenoviral serotypes in vitro and in the Ad5/NZW rabbit ocular model. Further studies are needed to advance topical immunoglobulin for treatment and prophylaxis of ocular infections.

Effect of formulation factors on in-vitro permeation of diclofenac from experimental and marketed aqueous eye drops through excised goat cornea

The effect of formulation factors on permeation of diclofenac from some experimental and marketed aqueous eye drops through excised goat cornea was evaluated. Raising the pH of formulation from 6.0 to 8.0 or diclofenac concentration from 0.05 to 0.15% (w/v) or adjusting tonicity with mannitol or addition of viscolizing agent decreased apparent permeability coefficient (Papp). Formulation (pH 7.4) containing sodium metabisulfite or EDTA or combination of methyl and propyl paraben showed significantly (p<0.05) higher Papp whereas benzalkonium chloride (BAC) had no effect and sorbic acid (SA) had reduced permeation. Surprisingly marketed drops containing BAC or SA, showed significantly (p<0.05) higher Papp and decreased in the order of Difen>Voveran>NSAID>Dicol>Diclolab. Lower pH (7.1-7.3) and surface tension of drops indicating presence of surfactant, could mediate increased permeation and presence of buffer could cause irritation on in vivo instillation. The marketed formulations showed corneal hydration >83% suggesting corneal damaging potential.

The effects of topical ketorolac and indomethacin on measles conjunctivitis: randomized controlled trial

PURPOSE

To compare the effect of topical ketorolac and indomethacin on measles conjunctivitis.

DESIGN

Prospective double-masked placebo-controlled randomized trial.

METHODS

Sixty-two patients with severe measles conjunctivitis were included in this study. All patients were hospitalized and randomly assigned to receive ketorolac 0.5% or indomethacin 0.1% in the right eye and artificial tears in the left eye. Conjunctival hyperemia, burning sensations, foreign-body sensations, and photophobia scores were conducted at baseline and at days seven and 14. A satisfaction score was evaluated at the end of the study.

RESULTS

The conjunctival injection score of the control eyes was significantly higher than those of the ketorolac- and indomethacin-treated eyes at day seven (P < .05). The conjunctival injection score of the ketorolac-treated eyes was lower than that of the indomethacin-treated eyes at days seven and 14, but this did not reach statistical significance. There was no significant difference in the burning and foreign-body sensations and in the photophobia scores among the study eyes at baseline, day seven, and day 14 (P > .05). There was no significant difference in the satisfaction score among the study eyes at the end of the study (P > .05).

CONCLUSIONS

In patients with measles during the first two weeks of infection, ketorolac and indomethacin were more effective than artificial tears in decreasing conjunctival hyperemia, but burning sensations, foreign-body sensations, and photophobia were unaffected.

Tolerability and Efficacy of N-Chlorotaurine in Epidemic Keratoconjunctivitis—a Double-Blind, Randomized, Phase-2 Clinical Trial

The aim of this study was to assess the tolerability and efficacy of N-chlorotaurine (NCT), an endogenous antimicrobial agent, in epidemic keratoconjunctivitis. In a prospective double-blind, randomized phase 2b study, the infected eyes were treated for 7 days with eye drops containing 1% aqueous solution of N-chlorotaurine (33 subjects) or gentamicin (27 subjects, control group). Adenovirus types 3, 4, 8, 19, and 37 were detected in 39 subjects (65%), enteroviruses in 8 (13.3%), and staphylococci in 5 (8.3%). Subjective and objective symptoms were scaled and added to a subjective and objective score, respectively, on day 1 (baseline), day 4, and day 8. Analyzing the whole study population, the subjective score on day 8 was lower in the NCT group (P = 0.016), whereas there were no differences in the objective score. However, in severe infections caused by adenovirus type 8 (n = 20) both the subjective and objective score were lower in the NCT group on day 4 (P = 0.003 and 0.015, respectively), which was also true for the subjective score on day 8 (P = 0.004) in this subgroup. The frequency of subepithelial infiltrates was similar in both groups. N-chlorotaurine was well-tolerated, shortened the duration of illness, and seems to be a useful causative therapeutic approach in severe epidemic keratoconjunctivitis.

Topical corticosteroids of limited potency promote adenovirus replication in the Ad5/NZW rabbit ocular model

PURPOSE

To determine the effect of topical therapy with several corticosteroids with limited potency on viral clearance in the adenovirus type 5 (Ad5) rabbit ocular model.

METHODS

Sixty rabbits were inoculated in both eyes with Ad5. On the first day, the rabbits were equally divided into four topical treatment groups: 0.12% prednisolone acetate (PA), 0.1% fluorometholone (FM), 1% rimexolone (RMX), and control. Treatment was administered four times daily, in both eyes, for 3 days. All eyes were cultured for virus on days 0, 1, 3, 4, 5, 7, 9, 11, 14, 16, 18, and 21.

RESULTS

Compared with the control group, treatment with PA, FM, and RMX significantly increased the number of Ad5 positive eye cultures from days 7-21. Fluorometholone and RMX prolonged the duration of Ad5 shedding, and FM increased the mean combined Ad5 titer from days 1-5 and 7-21.

CONCLUSIONS

Treatment of an experimental ocular adenovirus infection with PA, FM, and RMX for 3 days significantly enhanced adenovirus replication compared with the control group. Short-term treatment of EKC with several commercially available topical corticosteroids with limited potency may offer symptomatic relief, but may also delay viral clearance and promote office and community epidemics.

Short-term treatment With a potent topical corticosteroid of an acute ocular adenoviral infection in the New Zealand white rabbit

PURPOSE

To determine the effect of short-term topical therapy with 1% prednisolone acetate (PA) on normal immune adenoviral clearance in the rabbit ocular model.

METHODS

Thirty rabbits were topically inoculated in both eyes with adenovirus type 5 (Ad5). On day 1, the rabbits were divided into three topical treatment groups: 1% PA four times daily for 3 days, 1% PA four times daily for 5 days, control (artificial tears) four times daily for 5 days. Eyes were cultured for virus on days 0, 1, 3, 4, 5, 7, 9, 11, and 14.

RESULTS

Compared with the control group, treatment with 1% PA for 3 or 5 days significantly increased the total and daily number of Ad5-positive cultures from days 7 to 14, prolonged the duration of Ad5 shedding, and increased the mean combined Ad5 titer from days 1 to 5. In addition, treatment with 1% PA for 5 days increased the mean combined Ad5 titer from days 7 to 14.

CONCLUSION

Treatment of an ocular adenoviral infection with 1% PA for as little as four times daily for 3 days significantly enhanced adenoviral replication compared with the control group. Short-term corticosteroid treatment of acute adenoviral ocular infections with 1% PA should be used judiciously.