Clinical evaluation of the additive effect of diquafosol tetrasodium on sodium hyaluronate monotherapy in patients with dry eye syndrome: a prospective, randomized, multicenter study

Combination therapy with diquafosol tetrasodium and sodium hyaluronate in patients with dry eye after laser in situ keratomileusis

PURPOSE

To evaluate the possible advantages of combination therapy with diquafosol tetrasodium and sodium hyaluronate for dry eye after laser in situ keratomileusis (LASIK).

DESIGN

Prospective randomized comparative trial.

METHODS

A total of 206 eyes of 105 patients who underwent LASIK were enrolled in this study. Patients were randomly assigned to 1 of 4 treatment groups according to the postoperative treatment: artificial tears, sodium hyaluronate, diquafosol tetrasodium, and a combination of hyaluronate and diquafosol. Questionnaire responses reflecting subjective dry eye symptoms, uncorrected and corrected visual acuity, functional visual acuity, manifest refraction, tear break-up time, fluorescein corneal staining, Schirmer test, and corneal sensitivity were examined before and 1 week and 1 month after LASIK.

RESULTS

Distance uncorrected visual acuity was significantly better in the combination group than in the hyaluronate group 1 week and 1 month after LASIK. Near uncorrected visual acuity was significantly better in the combination group than in the artificial tear and diquafosol groups 1 week and 1 month after LASIK. Distance functional visual acuity improved significantly only in the combination group 1 month after LASIK. The Schirmer value in the combination group was significantly higher than that in the hyaluronate group at 1 month after LASIK. Subjective dry eye symptoms in the combination group improved significantly compared with those in the other groups 1 week after surgery.

CONCLUSIONS

Our results suggest that hyaluronate and diquafosol combination therapy is beneficial for early stabilization of visual performance and improvement of subjective dry eye symptoms in patients after LASIK.

P2Y2 receptor agonists for the treatment of dry eye disease: a review

Recent advances in the understanding of dry eye disease (DED) have revealed previously unexplored targets for drug therapy. One of these drugs is diquafosol, a uridine nucleotide analog that is an agonist of the P2Y2 receptor. Several randomized controlled trials have demonstrated that the application of topical diquafosol significantly improves objective markers of DED such as corneal and conjunctival fluorescein staining and, in some studies, tear film break-up time and Schirmer test scores. However, this has been accompanied by only partial improvement in patient symptoms. Although evidence from the literature is still relatively limited, early studies have suggested that diquafosol has a role in the management of DED. Additional studies would be helpful to delineate how different subgroups of DED respond to diquafosol. The therapeutic combination of diquafosol with other topical agents also warrants further investigation.

Effects of diquafosol sodium eye drops on tear film stability in short BUT type of dry eye

PURPOSE

To investigate the effects of diquafosol sodium (DQS) eye drops, a purinergic P2Y2 receptor agonist, on tear film stability in patients with unstable tear film (UTF).

METHODS

Two prospective studies were conducted. One was an exploratory nonrandomized trial on 39 eyes with dry eye symptoms and short tear film break-up time (BUT), but without epithelial damage. Changes in symptoms, BUT, Schirmer value, and ocular surface fluorescein staining (FS) scores were studied for 3 months. The other was a randomized clinical trial of DQS and artificial tears (AT) in 17 eyes with short BUT. Eyes with decreased Schirmer values (≤ 5 mm) were excluded. Changes in symptoms, BUT, FS scores, and tear film stability using continuous corneal topographic analysis were studied for 4 weeks.

RESULTS

In the exploratory study, while Schirmer values were not significantly increased, significant improvements in symptoms and BUT were noted at both 1 and 3 months. In the randomized clinical trial, significant improvements in symptoms were noted in the DQS group, but not in the AT group, at 2 weeks. BUT was significantly prolonged in the DQS group at 4 weeks but not in the AT group. No significant changes were noted in FS scores or tear film stability.

CONCLUSIONS

DQS improved subjective symptoms and prolonged BUT in eyes with UTF not associated with low tear secretion and ocular surface epithelial damage. Because many patients who have UTF are refractory to conventional treatments, DQS may offer benefits in the treatment of dry eyes.

Facilitation of tear fluid secretion by 3% diquafosol ophthalmic solution in normal human eyes

PURPOSE

To evaluate the increase in tear fluid volume induced by 3% diquafosol ophthalmic solution in normal human eyes.

DESIGN

Prospective, randomized, double-masked, comparative study.

METHODS

Twenty healthy adults (17 males and 3 females; mean age, 38.8 years) underwent topical instillation of 2 ophthalmic solutions, artificial tears in 1 eye and 3% diquafosol ophthalmic solution in the fellow eye, in a masked manner. The radius of curvature of the central lower tear meniscus was measured at 5, 10, 15, 30, and 60 minutes after instillation by use of reflective meniscometry, and subjects' self-evaluated symptoms of wetness and stinging using a visual analog scale.

RESULTS

Changes after instillation in the radius of curvature from baseline (artificial tear group vs diquafosol group; mean ± standard error of the mean) were as follows: at 5 minutes, -0.008 ± 0.012 vs 0.045 ± 0.013; at 10 minutes, 0.001 ± 0.014 vs 0.057 ± 0.016; at 15 minutes, -0.012 ± 0.014 vs 0.037 ± 0.019; at 30 minutes, -0.010 ± 0.016 vs 0.030 ± 0.025; and at 60 minutes, -0.029 ± 0.012 vs -0.020 ± 0.012. The diquafosol group showed significantly greater values from 5 to 30 minutes after instillation. Of the 40 eyes, 13 showed abnormal tear film breakup time (≤5 seconds). The diquafosol group had significantly more wetness at 15 minutes after instillation than did the artificial tear group.

CONCLUSIONS

Topical instillation of 3% diquafosol ophthalmic solution increases tear fluid on the ocular surface for up to 30 minutes in normal human eyes.

Emerging drugs for the treatment of dry eye disease

INTRODUCTION

Dry eye disease (DED) is a common, age-related ocular condition that in its mildest forms causes bothersome symptoms of ocular discomfort, fatigue, and visual disturbance that interfere with quality of life and in its more severe forms causes chronic pain and fluctuating vision. Though it is highly prevalent and costs billions of dollars to manage, current treatments have largely been inadequate, making it a frustrating condition, both for physicians and patients alike.

AREAS COVERED

This article will cover the recently discovered pathophysiology of DED that has prompted investigators to explore new molecules that target the core mechanisms that drive DED. These include anti-inflammatory/immune-modulatory drugs, secretagogues, lubricant, hormones, and autologous serum. Their potential mechanism of action and data from recent trials on efficacy/safety will be reviewed.

EXPERT OPINION

The emerging drugs have a vast range of putative mechanisms of action that may not only provide symptomatic relief but may potentially break the vicious cycle of DED and provide long-lasting cure. Current and future research may change our perspective on DED and redefine its treatment algorithms.

Topical diquafosol for patients with obstructive meibomian gland dysfunction

Aims

To evaluate the effect of topical diquafosol in patients with meibomian gland dysfunction (MGD) using tear film parameters and quantitatively analyse the meibomian gland morphology.

Subjects and Methods

The subjects were 19 eyes of 10 patients diagnosed with obstructive MGD. All subjects were given 3% diquafosol ophthalmic solution with instructions to use one drop four times a day. Ocular symptoms were scored from 0 to 14. Lid margin abnormalities were scored from 0 to 4. Changes in the meibomian glands were scored using non-contact meibography (meiboscore). Superficial punctate keratopathy (SPK) was scored from 0 to 3. Meibum was graded from 0 to 3. Tear film production was evaluated by Schirmer's test. Quantitative image analysis of the meibomian glands was performed using the original software.

Results

10 patients completed more than 4 months of therapy. Ocular symptoms, lid margin abnormalities, SPK score and meibum grade were decreased. Break-up time and tear film meniscus were increased. Mean ratio of the meibomian gland area was significantly increased after treatment (p<0.0001).

Conclusions

Quantitative image analysis was useful for evaluating the morphological changes of the meibomian glands. Topical diquafosol therapy was effective for patients with obstructive MGD.