Double-masked study of the effects of nepafenac 0.1% and ketorolac 0.4% on corneal epithelial wound healing and pain after photorefractive keratectomy

Topical analgesics for acute corneal pain: current options and emerging therapeutics

Acute corneal pain is a common complaint that causes significant distress to patients and continues to challenge therapeutic avenues for pain management. Current topical treatment options have marked limitations in terms of both efficacy and safety, thus often prompting the adjunctive use of systemic analgesics, including opioids. In general, there have not been extensive advancements in pharmacologic options for the management of corneal pain over the past several decades. Despite this, multiple promising therapeutic avenues exist which hold the potential to transform the ocular pain landscape, including druggable targets within the endocannabinoid system. This review will summarize the current evidence base for topical nonsteroidal anti-inflammatory drugs, anticholinergic agents, and anesthetics before focusing on several potential avenues in the setting of acute corneal pain management, including autologous tear serum, topical opioids and endocannabinoid system modulators.

Use of topical bromfenac for treating ocular pain and inflammation beyond cataract surgery: a review of published studies

Topical ophthalmic nonsteroidal anti-inflammatory drugs (NSAIDs) are commonly used to treat postoperative inflammation and pain following cataract surgery and for treatment and prophylaxis of pseudophakic cystoid macular edema (CME). Bromfenac is a brominated NSAID with strong in vitro anti-inflammatory potency. Like other ophthalmic NSAIDs, bromfenac is often used outside of the cataract surgery setting. This paper provides an overview of bromfenac’s preclinical ocular pharmacology and pharmacokinetics, followed by a review of 23 published clinical studies in which various marketed bromfenac formulations were used for conditions other than cataract surgery or pseudophakic CME. These include: post-refractive eye surgery; macular edema associated with diabetes, uveitis, or retinal vein occlusion; inflammation associated with age-related macular degeneration; pain related to intravitreal injections; and other ocular anterior segment and surface disorders with an inflammatory component. The published evidence reviewed supports the safety and effectiveness of bromfenac in these additional ophthalmic indications. Bromfenac was well tolerated when given alone or in combination with intravitreal anti-vascular endothelial growth factor agents, topical corticosteroids, or topical mast-cell stabilizers. The most common adverse event reported was ocular irritation. No serious adverse events (ie, corneal epithelial disorders) were reported, although the majority of studies did not systematically evaluate potential side effects. Corneal complications, such as melts reported with diclofenac and ketorolac, were not observed with bromfenac in the studies. In summary, published study data support the clinical utility of bromfenac in various ocular disorders beyond post-cataract surgery. Additional studies are warranted to further define the potential role of bromfenac ophthalmic solution in clinical practice.

Nepafenac Ophthalmic Suspension 0.3% for the Management of Ocular Pain After Photorefractive Keratectomy

PURPOSE

To investigate the effect of nepafenac 0.3% in a once daily dosage regarding pain and healing after photorefractive keratectomy (PRK).

METHODS

This was a prospective, comparative, contralateral randomized study of 35 patients undergoing PRK for the correction of low to moderate myopia and myopic astigmatism. After randomization, patients received nepafenac 0.3% ophthalmic suspension once daily in one eye (nepafenac 0.3% group) and nepafenac 0.1% ophthalmic suspension three times a day in the other eye (nepafenac 0.1% group) until the second postoperative day. Pain was evaluated every 2 hours on the day of the operation and then once daily using a scale ranging from 0 to 4. Patients were then examined at 2 weeks and 1, 3, 6, and 12 postoperative months. Visual acuity and subepithelial haze were also assessed.

RESULTS

No differences were detected between groups in pain scores, subepithelial haze scores, or visual acuity. Refractive predictability was also similar.

CONCLUSIONS

Nepafenac 0.3% ophthalmic suspension in a daily regimen after PRK seems to be an effective treatment for pain and ocular discomfort with effects similar to the 0.1% suspension. [J Refract Surg. 2018;34(3):171-176.].

Efficacy of systemic diclofenac sodium on intravitreal concentration

BACKGROUND

Nonsteroidal anti-inflammatory drugs (NSAIDs), as an alternative, are replacing corticosteroids in ocular inflammatory diseases. Diclofenac has been used mainly topically, and recent focus has been on intravitreal delivery. Both of these methods have been shown to have complications in long-term application.

PURPOSE

To assess the efficacy of slow release oral diclofenac sodium on intravitreal concentration in experimental model of chemically injured eyes.

METHODS

In an experimental double-masked clinical trial, right eyes of 24 albino rabbits were chemically injured by 1 N NaOH. One hour after chemical injury, 10 cc suspension gavage containing 100 mg slow release diclofenac sodium was administered in all cases. 2, 4, 6, 12, 24, 48 h after gavage, vitreous samples were obtained in all cases. Intravitreal concentration of diclofenac sodium was evaluated in all samples using high-performance liquid chromatography (HPLC) method.

RESULTS

Intravitreal diclofenac levels by oral intake were enhanced by the inflammation in all the measurements. In inflamed eyes, diclofenac concentration was ten times more than control eye (2.658 ± 0.344 vs. 0.242 ± 0.0279 and 1.617 ± 0.527 vs. 0.148 ± 0.095; in 2 and 4 h, respectively). After 6 h, diclofenac concentration was statistically different, although it reduced below 1 μg/ml.

CONCLUSION

Diclofenac is delivered to the inflamed eye more than healthy eye. It seems that by oral diclofenac consumption, it is possible to make a significant intravitreal concentration.

Predictors of Early Postoperative Pain After Photorefractive Keratectomy

PURPOSE

To compare the profiles of postoperative photorefractive keratectomy (PRK) pain between both eyes under the same conditions and to verify the preoperative predictors of pain such as gender, anxiety, knowledge of the procedure, and spherical equivalent refractive error (SERE).

METHODS

This prospective study included 86 eyes of 43 patients with myopia who underwent PRK in both eyes at an interval of 14 days between the procedures. Before surgery, subjects answered the State Anxiety Inventory. After surgery, usual PRK pain treatment was given. Subjects answered the Visual Analog Scale, the Brief Pain Inventory (BPI), and the McGill Pain Questionnaire at 1, 24, 48, 72, and 96 hours after surgery. Pain scores and anxiety were compared between each eye using the Wald test and paired Student t test, respectively. The Wald test was performed for gender and SERE for each eye separately.

RESULTS

There were no statistically significant differences between both eyes for all time points regarding the Visual Analog Scale, BPI, and McGill Pain Questionnaire-Pain Rating Index pain scores. Subjects were less anxious on average before the second surgery compared with before the first surgery (P < 0.001); however, it was not related to pain ratings after surgery. Gender did not significantly affect any scale of pain, and the SERE between -3 diopters (D) and -5 D (P = 0.035) revealed effects on the BPI.

CONCLUSIONS

The profiles of postoperative pain after PRK were similar between both eyes under the same conditions. In this study, a high SERE was the only predictor for increased pain after PRK.

Efficacy and safety of pain relief medications after photorefractive keratectomy: review of prospective randomized trials

The objective of this review was to provide a comprehensive overview and comparison of results from all prospective randomized trials published to date of medications used to treat pain after photorefrative keratectomy (PRK). A PubMed database search revealed 23 prospective and randomized studies. They included the following classes of medications: nonsteroidal antiimflammatory drugs (NSAIDs), anesthetics, opiates, acetaminophen, gabapentin, and pregabalin. The studies found that although the efficacy of drugs tended to be similar, tetracaine 1% and nepafenac 0.1% tended to have the most analgesic effect. Delayed corneal reepithelialization was a common side effect of both topical anesthetics and topical NSAIDs. Tetracaine 1% resulted in the most significant delay in reepithelialization when tested against placebo control compared with other topical medications tested against placebo. Concomitant use of topical NSAIDs and topical anesthetics, especially tetracaine, may have to be avoided to minimize the risk for delayed corneal healing.

FINANCIAL DISCLOSURE

Neither author has a financial or proprietary interest in any material or method mentioned.

Pterygium removal using a polyethylene glycol hydrogel adherent ocular bandage

PURPOSE

To describe the result of using a polyethylene glycol hydrogel contact lens (ReSure; Ocular Therapeutix, Inc, Bedford, MA) as a protective bandage over denuded areas of Tenons after pterygium removal.

METHODS

Five sequential patients underwent pterygium removal with a conjunctival autograft and painting of bare Tenons in the area of the graft retrieval with a biodegradable polymer, and these patients were followed for 1 year for immediate postoperative pain, epithelial healing, and long-term conjunctival scarring.

RESULTS

All patients showed prolonged persistence of the polymer for up to 8 to 10 weeks with resultant increased conjunctival inflammation and scarring with no evidence of decreased postoperative pain.

CONCLUSIONS

This hydrogel polymer seems to cause prolonged inflammation and resultant scarring when used over extended areas of Tenons, and it has no role in reducing pain after pterygium surgery.

Evaluation of analgesic efficacy of bromfenac sodium ophthalmic solution 0.09% versus ketorolac tromethamine ophthalmic solution 0.5% following LASEK or Epi-LASIK

Background

To evaluate the analgesic efficacy of bromfenac sodium ophthalmic solution 0.09% compared with ketorolac tromethamine ophthalmic solution 0.5% in laser epithelial keratomileusis (LASEK) or epithelial keratomileusis (epi-LASEK), sometimes referred to as epi-LASIK.

Methods

Eighty eyes (from 40 patients, 18 men and 22 women) undergoing bilateral simultaneous LASEK or epi-LASEK were randomized to receive ketorolac in one eye and bromfenac in the other. Mean age was 33.13 ± 9.34 years. One drop of bromfenac or ketorolac was instilled in each eye 15 minutes and one minute prior to surgery, and two and four hours following surgery. Patients were instructed to instill the medications on-label each day through postoperative day 4. The subjects completed pain and visual blurriness assessments from day of surgery to postoperative day 4. Uncorrected visual acuity was tested on postoperative days 1 and 6.

Results

For each of the five days, pain scores for bromfenac-treated eyes were significantly less than that for ketorolac-treated eyes (P < 0.01). Of the 40 patients, 32 (80%) said bromfenac provided better postoperative analgesia than ketorolac. There was no statistically significant difference in visual blurriness scores between the two groups (P > 0.1). Uncorrected visual acuity did not vary significantly between the treatment groups (P > 0.1). No serious adverse events were noted.

Conclusion

Bromfenac is subjectively superior to ketorolac in reducing postoperative pain following LASEK or epi-LASEK. The subjects tolerated the drugs well with no serious adverse outcomes and no difference in uncorrected visual acuity.

Topical ophthalmic NSAIDs: a discussion with focus on nepafenac ophthalmic suspension

The removal of diclofenac sodium ophthalmic solution as a viable pharmaceutical entity in September 1999 from the US market spurred considerable interest in the general safety and effectiveness of topical ophthalmic NSAIDs for treatment of anterior segment inflammation. In late 1999 the use of topical ocular NSAIDs declined in the US as a result of incidents involving corneal melts and toxicity surrounding use of generic diclofenac. However, since the removal of diclofenac sodium ophthalmic solution from the marketplace, ophthalmic NSAIDs have regained use as viable pharmacotherapeutic entities. Moreover, several new ophthalmic NSAID products have recently been introduced for commercial use in the US including the novel chemical entity nepafenac. The purpose of this report is to revisit the use of topical ophthalmic NSAIDs for the treatment of surgically induced anterior segment inflammation with a particular focus on nepafenac. Nepafenac is unique among ophthalmic NSAIDs in that it is a prodrug deaminated to amfenac, a highly effective non-selective cyclooxygenase inhibitor. In the case of topical ophthalmic NSAIDs, practitioners should carefully weigh the cost-benefit of implementing “highly potent” new drug products because perturbations in pharmacodynamic response due to the inherent novelty in terms of chemical designs may outweigh the demonstrated replicative pharmacologic action of all topical ophthalmic NSAIDs.

Effect of preemptive topical diclofenac on postoperative pain relief after photorefractive keratectomy

PURPOSE

To assess the prophylactic effect of preoperative application of topical diclofenac on postoperative pain control in patients having photorefractive keratectomy (PRK).

SETTING

Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran.

DESIGN

Randomized masked clinical trial.

METHODS

In this paired-eye study, patients having bilateral PRK received 1 drop of diclofenac 0.1% in 1 eye and 1 drop of placebo in the fellow eye 2 hours before PRK. Postoperatively, both arms of the trial (both eyes of each patient) received topical diclofenac every 6 hours for 2 days. One day and 2 days postoperatively, patients were asked to rate the perceived pain in each eye using an 11-point verbal numerical rating scale. A trained examiner noted the eye-specific responses.

RESULTS

All 70 patients (140 eyes) completed the study and were included in the statistical analysis. Twenty-four hours after PRK, patients reported pain scores that were clinically and statistically significantly lower in the eyes pretreated with diclofenac than in the fellow eyes (0.97 versus 2.09) (P=.018). Pain scores at 2 days did not differ significantly (P=.877).

CONCLUSION

Administration of a single drop of topical diclofenac 0.1% 2 hours before PRK seemed to increase the efficacy of postoperative pain management in a clinically and statistically significant manner.

FINANCIAL DISCLOSURE

No author has a financial or proprietary interest in any material or method mentioned.

Ex vivo corneal epithelial wound healing following exposure to ophthalmic nonsteroidal anti-inflammatory drugs

Purpose:

Ketorolac 0.45% is a new formulation of topical ketorolac in which preservative (benzalkonium chloride, BAK) was removed and carboxymethylcellulose (CMC) was added to improve tolerability and reduce dosing frequency. This study compared the effects of ketorolac 0.45% on corneal wound healing to prior ketorolac formulations (0.4% and 0.5%), bromfenac 0.09%, and nepafenac 0.1%.

Methods:

Two parallel-group comparisons were performed in series. A 5-mm central epithelial wound was made in fresh porcine corneas. After 24 hours in minimum essential medium (MEM), corneas were incubated for 10 minutes with study drugs, Triton X-100 1% (positive control), or MEM (negative control), followed by 24 hours in MEM. The remaining wound area was stained, photographed, and quantified (pixels). Study 1 compared ketorolac 0.45% to ketorolac 0.4% and ketorolac 0.5%. Study 2 compared ketorolac 0.45% to bromfenac 0.09% and nepafenac 0.1%.

Results:

The mean (±SD) original wound area was 200,506 ± 4,363 pixels, which was reduced to 59,509 ± 4850 at 48 hours after exposure to Triton X-100 1%. In study 1, the mean remaining wound areas at 48 hours in pixels were 2969 ± 1633 with MEM, 586 ± 299 with ketorolac 0.45% (significantly reduced, P < 0.05 vs all other treatments), 10,228 ± 7541 with ketorolac 0.4%, and 50,674 ± 33,409 with ketorolac 0.5% (significantly enlarged, P < 0.05 vs MEM). In study 2, the mean remaining wound areas at 48 hours were 565 ± 1263 with MEM, 322 ± 229 with ketorolac 0.45% (significantly reduced, P < 0.01 vs bromfenac 0.09% and nepafenac 0.1%), 29,093 ± 14,295 with bromfenac 0.09% (significantly enlarged, P <0.01 vs MEM) and 47,322 ± 13,736 with nepafenac 0.1% (significantly enlarged, P < 0.01 vs MEM and vs bromfenac 0.09%).

Conclusion:

Corneas treated with ketorolac 0.45% healed as rapidly as those treated with MEM, likely secondary to addition of CMC and removal of BAK. In the ex vivo corneal organ culture model, ketorolac 0.45% had statistically less impact on corneal re-epithelialization than prior ketorolac formulations (0.4% and 0.5%), bromfenac 0.09%, and nepafenac 0.01%.

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.

Effects of nonsteroidal ophthalmic drops on epithelial healing and pain in patients undergoing bilateral photorefractive keratectomy (PRK)

The present study, which was designed as a prospective, double-masked, randomized, controlled, single-site study, was conducted to compare the effects of 3 approved ophthalmic nonsteroidal anti-inflammatory drugs-nepafenac ophthalmic suspension 0.1% (Nevanac; Alcon Laboratories, Inc., Fort Worth, Tex), ketorolac tromethamine ophthalmic solution 0.4% (Acular LS; Allergan, Irvine, Calif), and bromfenac 0.09% (Xibromtrade mark; ISTA Pharmaceuticals, Irvine, Calif)-on corneal reepithelialization and postoperative pain control in patients undergoing photorefractive keratectomy. In addition to nonsteroidal anti-inflammatory drugs, each patient received an antibiotic-moxifloxacin hydrochloride ophthalmic solution 0.5% (nepafenac group) or gatifloxacin ophthalmic solution 0.3% (ketorolac and bromfenac groups). All treatments were administered 3 times daily beginning 1 d preoperatively and continuing for 1 wk postoperatively; prednisolone acetate 1.0% was administered concurrently 4 times daily. Bandage contact lenses were replaced at each postoperative visit for corneal staining and epithelial defect grading. Self-evaluation of pain relief was recorded on postoperative days 1 and 3 with the use of a visual analog scale. A total of 29 patients (58 eyes) were enrolled and underwent bilateral custom photorefractive keratectomy. Mean time to reepithelialization was 5.50+/-1.59 d for the nepafenac 0.1% group, 5.62+/-1.23 d for the ketorolac 0.4% group, and 7.25+/-2.53 d for the bromfenac 0.09% group. A significant difference was detected between nepafenac 0.1% and bromfenac 0.09% and between ketorolac 0.4% and bromfenac 0.09% (P<.05). Significant reductions in pain scores were observed with nepafenac 0.1% on day 1 (-1.13) and day 3 (-1.32), ketorolac 0.4% on day 3 (-0.88), and bromfenac 0.09% on day 3 (-0.83). No adverse events were reported. Eyes treated with nepafenac 0.1% or ketorolac 0.4% achieved complete reepithelialization significantly faster than those treated with bromfenac 0.09%. Daily contact lens removal and application of fluorescein may have delayed reepithelialization in the overall population; however, the effect would have been the same in all 3 groups. Pain relief with nepafenac 0.1% was achieved sooner than with ketorolac 0.4% or bromfenac 0.09%.