Effect of ketorolac on herpes simplex virus type one ocular infection in rabbits

Resorbable nanofibrous membranes for local and sustained co-delivery of acyclovir and ketorolac in herpes therapy

Herpes simplex and herpes zoster are both viral infections caused by members of the herpesvirus family. The former is characterized by painful, fluid-filled blisters or sores on the skin and mucous membranes, while the latter presents as a painful rash with blisters, typically occurring in a single band or patch along one side of the body. The treatment remains a challenge since current antiviral therapy via oral administration may lead to unfavorable side effects such as headaches, nausea, and diarrhea. This study used electrospinning to develop biodegradable nanofibrous poly(lactic-co-glycolic acid) (PLGA) membranes for delivery of both acyclovir and ketorolac. The structure of the spun nanofibers was assessed via scanning electron microscopy (SEM), and the appearance of loaded acyclovir and ketorolac in the nanofibers was confirmed with Fourier-transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC). Release profiles of these drugs from the nanofibrous membranes were assessed using in vitro elution studies, high-performance liquid chromatography (HPLC) assays, and in vivo drug release patterns. The electrospun nanofibers had a size range of 283-725 nm in diameter, resembling the extracellular matrix of natural tissue and demonstrated excellent flexibility and extensibility. Notably, the drug-eluting nanofibers exhibited an extended release of high levels of acyclovir and ketorolac over a 21-day period. Thus, biodegradable drug-eluting membranes with a prolonged drug release could be a potential therapeutic approach for treating herpes infections.

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.

Topical indomethacin solution versus dexamethasone solution for treatment of inflamed pterygium and pinguecula: a prospective randomized clinical study

PURPOSE

To compare the effect of topical indomethacin 0.1% solution with the effect of topical dexamethasone 0.1% phosphate solution on signs and symptoms of inflamed pterygium and pinguecula.

METHODS

Of 50 consecutive patients who had inflamed pterygia (n = 17) or pingueculae (n = 33), met the study criteria, and signed an informed consent, one eye of each patient was evaluated in a comparative, prospective, randomized, double-masked, controlled study. Objective signs (conjunctival congestion, redness and edema, and staining of cornea) and subjective complaints (photophobia, pain, foreign-body sensation, discomfort, and tearing) were evaluated and scored. We also evaluated "total signs," "total symptoms," and "total score." Group 1 (n = 25) received topical indomethacin 0.1% solution, and group 2 (n = 25) received a topical dexamethasone phosphate 0.1% solution six times daily for 3 days, then four times daily over the following 11 days. Patients were examined before treatment, on days 3, 7, and 14 after the treatment was initiated, and 2 and 4 weeks after the treatment was discontinued.

RESULTS

In both groups, the scores for "total signs," "total symptoms," and "total score" were significantly lower (P = .001) by day 14. There were no differences between groups 1 and 2 for "total signs," "total symptoms," and "total score" at days 3, 7, and 14 (P = .07 to P = .88). After treatment was discontinued, the dexamethasone-treated group experienced a significantly greater recurrence of "total signs" (P = .023 at day 30, P = .02 at day 45), but there was no statistically significant difference in "total symptoms" and "total score." Patients in group 2 reported more stinging after drops were administered than patients in group 1 (P = .002).

CONCLUSIONS

This study indicates that topical indomethacin 0.1% solution is as effective as topical dexamethasone phosphate 0.1% solution for the treatment of inflamed pterygium and pinguecula and, therefore, is suggested as an effective treatment for these conditions.

Evaluation of topical 0.03% flurbiprofen drops in the treatment of herpetic stromal keratitis

PURPOSE

The management protocol for herpetic stromal keratitis (HSK) is still controversial. We have attempted to compare the relative efficacy of topical dexamethasone 0.01% and flurbiprofen 0.03% in combination with topical acyclovir 3% in HSK.

METHODS

In this institutional, prospective, randomized, controlled, double-blind study, 45 clinically diagnosed cases of HSK were randomly distributed into three coded treatment groups--topical placebo, dexamethasone 0.01%, and flurbiprofen 0.03% each in tapering frequency and in combination with acyclovir 3% ointment five times per day for four weeks. Therapeutic response was assessed every third day for four weeks. Decoding of the treatment groups was done at the conclusion of the study and data analysed.

RESULTS

Four-week success rate was 93.3% (14 of 15) in the dexamethasone-acyclovir treatment group, 66.7% (10 of 15) in the flurbiprofen-acyclovir treatment group and 20% (3 of 15) in the placebo-acyclovir treatment group.

CONCLUSION

While dexamethasone in combination with acyclovir gives the best results in HSK with minimal side-effects, the role of topical flurbiprofen seems promising.

Double-masked, paired-comparison clinical study of ketorolac tromethamine 0.5% ophthalmic solution compared with placebo eyedrops in the treatment of seasonal allergic conjunctivitis

In a multicenter, double-masked, clinical study, we compared the ocular safety and efficacy of ketorolac 0.5% ophthalmic solution with placebo in alleviating the signs and symptoms of allergic conjunctivitis. The study was conducted in 93 patients who received one drop of the appropriate treatments in each eye, four times a day, for seven days. Of these subjects, 74 were evaluated for efficacy. The principal clinical sign of allergic conjunctivitis, conjunctival inflammation, and six allergic symptoms (itching, swollen eyes, burning or stinging, discharge or tearing, foreign body sensation, and photophobia) were evaluated by the investigators at midweek (day 3 or 4) and at the end of the study (day 7 or 8). Ketorolac was superior to placebo in reducing conjunctival inflammation (p = 0.003) and itching (p = 0.020), the principal clinical symptom, at the final examination. In addition, ketorolac was favored over placebo in reducing the other five symptoms evaluated. On the day of final examination, overall therapeutic response evaluated by the investigators rated ketorolac as superior to placebo (p = 0.007). A significant placebo effect was noted in this study, as has been previously reported in clinical studies of allergic conjunctivitis patients. Results of this study demonstrate that 0.5% ketorolac ophthalmic solution used topically four times daily, for seven days, was effective in alleviating the principal sign and the symptoms associated with allergic conjunctivitis.

Cyclo-oxygenase inhibitors in ophthalmology

Cyclo-oxygenase inhibitors, which are formulated as ophthalmic eyedrop preparations, have recently become commercially available for use by ophthalmologists in the United States to inhibit intraoperative miosis during cataract surgery and to prevent postoperative inflammation. In addition, they are available worldwide as ocular antiinflammatory drugs and are used in the prevention and treatment of pseudophakic and aphakic cystoid macular edema. Understanding the rationale behind the use of these agents requires an understanding of the pathophysiology of the cyclo-oxygenase inhibitors. In this review recent advances in laboratory and clinical science are emphasized. The role of COIs during and following surgery is examined.

Cryogenic induced ocular HSV-1 reactivation is enhanced by an inhibitor of the lipoxygenase pathway

Reactivation of latent herpes simplex virus type 1 (HSV-1) has been shown to occur in response to localized inflammation. Prostaglandins and lipoxygenase products [eg. hydroxyeicosatetraenoic acids, (HETEs)] are associated with inflammation and, therefore, may play a role in HSV-1 infection and reactivation. In the rabbit cornea, alkali injury, cryogenic injury, and acute HSV-1 infection promote the synthesis of HETEs. Recently, a platelet activating factor antagonist, ginkgolide B (BN 52021) has been found to specifically inhibit the corneal synthesis of HETEs after alkali injury. If the induction of HETEs after injury is related to HSV reactivation and severity of infection, BN 52021 may alter HSV reactivation and the severity of infection by reducing the production of HETEs. To study the effect of BN 52021 on HSV-1 reactivation, cryogenic corneal lesions were produced in ten HSV-1 latently infected rabbits. Five rabbits were treated with topical and intravenous BN 52021 while the remaining five rabbits received topical artificial tears and intravenous saline. In the BN 52021 treated group, 90% (9/10) of the eyes and 53% (35/66) of the total ocular cultures were positive for HSV-1. In the control group, 60% (6/10) of the eyes, and 27% (18/66) of the ocular swabs were positive for HSV-1. The total number of positive cultures was significantly greater (p less than .05) in the BN 52021 treated rabbits. By increasing the number of positive HSV ocular cultures, BN 52021 appeared to act similarly to other inhibitors of arachidonic acid metabolism such as steroidal and nonsteroidal anti-inflammatory agents.