Long-Term Safety and Efficacy of Perfluorohexyloctane Ophthalmic Solution for the Treatment of Patients With Dry Eye Disease: The KALAHARI Study.

PURPOSE: The aim of this study was to assess the long-term safety and efficacy of perfluorohexyloctane (PFHO) ophthalmic drop (formerly NOV03) for treatment of dry eye disease (DED). METHODS: KALAHARI was a phase 3, multicenter, single-arm, open-label extension study in patients aged 18 years or older with DED associated with Meibomian gland dysfunction who completed the randomized, double-masked, hypotonic saline-controlled GOBI study. Patients instilled 1 drop of PFHO (MIEBO, Bausch + Lomb) 4 times daily in both eyes for 52 weeks. Safety assessments included adverse events, best-corrected visual acuity, slit-lamp biomicroscopy, intraocular pressure, and dilated fundoscopy. Efficacy end points included change from GOBI study baseline in total corneal fluorescein staining and eye dryness score (0-100 visual analog scale). RESULTS: Overall, 208 patients from GOBI (PFHO [n = 97]; saline [n = 111]) were rolled over into KALAHARI. Twenty-nine patients (13.9%) had ≥1 ocular adverse event, with most being mild or moderate in severity; the most common ocular adverse events were vitreous detachment (1.9%), allergic conjunctivitis (1.4%), blurred vision (1.4%), and increased lacrimation (1.4%). Other safety end points were unremarkable. For patients continuing PFHO from GOBI, improvements in total corneal fluorescein staining and visual analog scale dryness scores observed in GOBI were maintained throughout KALAHARI. Patients treated with saline in GOBI and switched to PFHO in KALAHARI showed improvements in total corneal fluorescein staining and visual analog scale scores by week 4 that were maintained for the rest of the study. CONCLUSIONS: PFHO was safe and well tolerated and maintained efficacy for improving signs and symptoms of DED in this year-long study of patients with DED associated with Meibomian gland dysfunction.

NOV03 for Signs and Symptoms of Dry Eye Disease Associated With Meibomian Gland Dysfunction: The Randomized Phase 3 MOJAVE Study.

PURPOSE: To evaluate the efficacy and safety of NOV03 (perfluorohexyloctane) ophthalmic drop for the treatment of signs and symptoms of dry eye disease (DED) associated with meibomian gland dysfunction (MGD). DESIGN: Randomized, double-masked, controlled trial. METHODS: Patients ≥18 years of age with a history of DED and signs of MGD were randomly assigned 1:1 to treatment with NOV03 or hypotonic saline (0.6%) 4 times daily for 8 weeks. The primary sign and symptom endpoints were change from baseline to week 8 in total corneal fluorescein staining (tCFS; National Eye Institute scale) and eye dryness score (0-100 visual analog scale), respectively. RESULTS: A total of 620 patients (NOV03, n = 311; saline, n = 309) were randomized and treated. Least-squares (LS) mean change from baseline to week 8 was statistically significantly greater for NOV03 compared with saline for both tCFS (-2.3 vs -1.1; LS mean treatment difference, -1.2 [95% confidence interval -1.7 to -0.8]; P < .001) and visual analog scale dryness score (-29.4 vs -19.2; LS mean treatment difference, -10.2 [95% CI -14.4 to -6.1]; P < .001), with statistically significant between-group differences observed as early as week 2. The incidence of ocular adverse events was similar for NOV03 (12.9%) and saline (12.3%). There were no serious adverse events and no adverse events leading to treatment discontinuation. CONCLUSIONS: In this randomized controlled trial of patients with DED associated with MGD, NOV03 significantly reduced both signs and symptoms of DED compared with hypotonic saline control. NOV03 was well tolerated, with an adverse event profile similar to that of saline.

NOV03 for Dry Eye Disease Associated with Meibomian Gland Dysfunction: Results of the Randomized Phase 3 GOBI Study.

PURPOSE: To evaluate the efficacy and safety of NOV03 (perfluorohexyloctane) ophthalmic drop in patients with dry eye disease (DED) associated with meibomian gland dysfunction (MGD). DESIGN: Eight-week, phase 3, multicenter, randomized, double-masked, saline-controlled study. PARTICIPANTS: Adults ≥ 18 years with a history of DED for ≥ 6 months, tear film breakup time of ≤ 5 seconds, Schirmer I test (without anesthesia) score ≥ 5 mm, MGD score ≥ 3 (0-15 scale), and total corneal fluorescein staining (tCFS) score ≥ 4 and ≤ 11 (0-15 National Eye Institute [NEI] scale). METHODS: Patients were randomized 1:1 to NOV03 or hypotonic (0.6%) saline 4 times daily. MAIN OUTCOME MEASURES: The primary sign and symptom end points were change from baseline in tCFS and eye dryness score (0-100 visual analog scale [VAS]) at week 8. Key secondary end points were change from baseline in eye dryness score at week 2, tCFS at week 2, eye burning or stinging score (0-100 VAS) at week 8, and central corneal fluorescein staining (cCFS; 0-3 NEI scale) at week 8. RESULTS: Of the 599 patients randomized, 597 were treated (NOV03, n = 303; saline, n = 294). At week 8, improvement from baseline was significantly greater (P < 0.001) with NOV03 versus saline for tCFS (least square [LS] mean treatment difference, -0.97; 95% confidence interval [CI]: -1.40, -0.55) and VAS dryness score (-7.6; 95% CI: -11.8, -3.4). Improvement from baseline also significantly (P < 0.01) favored NOV03 on all key secondary end points: LS mean treatment difference (95% CI) was -4.7 (-8.2, -1.2) for VAS dryness score at week 2, -0.6 (-0.9, -0.2) for tCFS at week 2, -5.5 (-9.5, -1.6) for VAS burning or stinging score at week 8, and -0.2 (-0.4, -0.1) for cCFS at week 8. Most ocular adverse events (AEs) were mild in severity; no serious ocular AEs occurred. One patient discontinued NOV03 because of an AE (eye irritation). CONCLUSIONS: In patients with DED associated with MGD, NOV03 demonstrated statistically significant and clinically meaningful improvements versus hypotonic saline in signs and symptoms of DED and was well tolerated. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found after the references.

A randomized, placebo-controlled study to evaluate safety and pharmacokinetics of inhaled ribavirin.

Ribavirin is an inosine monophosphate dehydrogenase inhibitor. Studies suggest ribavirin aerosol could be a safe and efficacious treatment option in the fight against coronaviruses. However, current treatment is long (12-18 h per day, 3-7 days), limiting clinical utility. A reduction in treatment time would reduce treatment burden. We aimed to evaluate safety and pharmacokinetics (PK) of four, single-dose regimens of ribavirin aerosol in healthy volunteers. Thirty-two subjects were randomized, to four cohorts of aerosolized ribavirin (active) or placebo. Cohort 1 received 50 mg/ml ribavirin/placebo (10 ml total volume); cohort 2, 50 mg/ml ribavirin/placebo (20 ml total volume); cohort 3, 100 mg/ml ribavirin/placebo (10 ml total volume); and cohort 4, 100 mg/ml ribavirin/placebo (20 ml total volume). Intense safety monitoring and PK sampling took place on days 1, 2, 3, and 40. Subjects were (mean ± SD, active vs. placebo) aged 57 ± 4.5 vs. 60 ± 2.5 years; 83% vs. 88% were female; and 75% vs. 50% were Caucasian. Some 12.5% (3/24) and 25% (2/8) experienced at least one treatment-emergent adverse event (TEAE) (two moderate; five mild) in the active and placebo groups, respectively. No clinically significant safety concerns were reported. Mean maximum observed concentration (Cmax ) and area under the curve (AUC) values were higher in cohort 4, whereas cohorts 2 and 3 showed similar PK values. Ribavirin absorption reached Cmax within 2 h across cohorts. Four single-dose regimens of ribavirin aerosol demonstrated systemic exposure with minimal systemic effects. Results support continued clinical development of ribavirin aerosol as a treatment option in patients with coronaviruses.

Loteprednol etabonate gel 0.5% vs prednisolone acetate suspension 1% for the treatment of inflammation after cataract surgery in children.

PURPOSE: To compare loteprednol etabonate (LE) gel 0.5% with prednisolone acetate suspension (PA) 1% for the treatment of inflammation after cataract surgery in children. SETTING: Eleven sites in the United States. DESIGN: Randomized, double-masked, parallel-group, noninferiority study. METHODS: Eligible patients were aged 11 years or younger and candidates for routine, uncomplicated cataract surgery. Patients were randomized to a 4-week postsurgical regimen with LE gel 0.5% or PA 1%, twice on the day of surgery, 4 times daily for 2 weeks, twice daily for 1 week, and once daily for 1 week. Assessments included anterior chamber (AC) cells/flare, anterior chamber inflammation (ACI), synechiae, precipitates on the intraocular lens/cornea, visual acuity, and intraocular pressure. RESULTS: The intent-to-treat population comprised 105 patients (LE gel, n = 53; PA 1%, n = 52) including 52 patients aged 3 years or younger. Patients achieved a similar mean ACI grade on postoperative day 14 (primary efficacy endpoint) whether treated with LE gel 0.5% or PA 1% (difference = 0.006, 2-sided 95% CI, -0.281 to 0.292). Similar ACI outcomes additionally were observed in patients aged 3 years or younger. LE gel 0.5% and PA 1% also appeared equally effective in resolving inflammation at all visits (days 7, 14, and 28 postsurgery), based on categorical distributions of ACI, AC cells, and AC flare scores/grades (P ≥ .06). Synechiae and corneal/IOL precipitates occurred infrequently with no significant differences between groups. No safety or tolerability concerns were identified, including no treatment-related IOP increases. CONCLUSIONS: LE gel 0.5% was safe and effective in treating pediatric postcataract surgical inflammation, with similar outcomes as PA 1%.

Loteprednol etabonate (submicron) ophthalmic gel 0.38% dosed three times daily following cataract surgery: integrated analysis of two Phase III clinical studies.

PURPOSE: To evaluate the efficacy and safety of a submicron formulation of loteprednol etabonate (LE) gel 0.38% instilled three times daily (TID) compared with vehicle for the treatment of inflammation and pain following cataract surgery with intraocular lens implantation, integrated across two multicenter, double-masked, randomized, parallel-group, Phase III studies. PATIENTS AND METHODS: Subjects ≥18 years of age with anterior chamber (AC) cells ≥grade 2 (6-15 cells) on day 1 after cataract surgery were randomized to receive 1 drop of LE gel 0.38% TID, twice daily (not reported/analyzed herein), or vehicle instilled in the study eye for 14 days. Primary endpoints were the proportion of subjects with resolution of AC cells and grade 0 (no) pain at postoperative day 8. Safety outcomes included adverse events (AEs), ocular signs, fundoscopy results, visual acuity, intraocular pressure (IOP), and tolerability (drop comfort and ocular symptoms). RESULTS: The integrated intent-to-treat population included 742 subjects (LE gel 0.38% TID, n=371; vehicle, n=371). Significantly more subjects in the LE gel 0.38% TID group compared with the vehicle group had complete resolution of AC cells (29.6% vs 15.1%) and grade 0 pain (74.4% vs 48.8%) at day 8 (P<0.0001 for both). LE gel 0.38% TID was safe and well tolerated, with only 1 LE-treated subject experiencing an IOP elevation ≥10 mm Hg. Most treatment-related AEs were mild and occurred less frequently with LE gel 0.38% than with vehicle. The majority (>75%) of subjects in each treatment group reported no drop discomfort. There were no reports of blurred vision with LE gel. CONCLUSION: The results of this integrated analysis indicate that LE (submicron) gel 0.38% administered TID is safe and effective for the treatment of ocular inflammation and pain following cataract surgery, with minimal risk of IOP elevation.

Low-dose brimonidine for relief of ocular redness: integrated analysis of four clinical trials.

BACKGROUND: The aim of this study was to provide an integrated analysis of safety and efficacy data for brimonidine tartrate ophthalmic solution 0.025 per cent (low-dose; Bausch & Lomb Incorporated), a topical vasoconstrictor for relief of ocular redness. METHODS: Integrated efficacy data from two randomised, double-masked, vehicle-controlled studies in subjects with ocular redness as well as safety data from the two efficacy studies, a vehicle-controlled safety study, and a pharmacokinetic study were analysed. Efficacy outcomes analysed included investigator-assessed ocular redness (scale, 0-4) before treatment instillation and at five to 240 minutes post-instillation on Day 1, at five minutes post-instillation on Days 15 and 29, and one week after treatment discontinuation (Day 36), and redness self-assessed by subjects recorded daily in diaries. Safety assessments included adverse events, ophthalmic examinations, and rebound redness upon treatment discontinuation. Drop comfort (scale, 0-10) was a tolerability measure. RESULTS: The efficacy population included 117 subjects (brimonidine, n = 78; vehicle, n = 39). The safety population included 635 subjects (brimonidine, n = 426; vehicle, n = 209). Investigator-assessed ocular redness was significantly lower with brimonidine versus vehicle at all post-instillation time points on Day 1 (mean change from pre-instillation of -1.4 units for brimonidine and -0.2 units for vehicle; p < 0.0001). Subject-assessed ocular redness was also significantly lower with brimonidine versus vehicle (mean treatment difference in average daily ratings of -0.9; p < 0.0001). There was no evidence of tachyphylaxis through Day 29 and rebound redness was rare. Incidence of ocular adverse events was low, the most common being reduced visual acuity (brimonidine, 4.0 per cent; vehicle, 4.3 per cent) and conjunctival hyperaemia (2.6 and 2.9 per cent, respectively). Both brimonidine and vehicle were rated as very comfortable (mean post-instillation scores, 0.4-0.5). CONCLUSION: In this integrated analysis, low-dose brimonidine significantly reduced ocular redness with no tachyphylaxis, and minimal rebound redness, and was generally safe and well tolerated.

Submicron loteprednol etabonate ophthalmic gel 0.38% for the treatment of inflammation and pain after cataract surgery.

PURPOSE: To assess the safety and efficacy of a 0.38% submicron formulation of loteprednol etabonate (LE) gel for the treatment of postoperative inflammation and pain after cataract surgery. SETTING: Forty-five United States ophthalmology practices. DESIGN: Double-masked vehicle-controlled randomized parallel group study. METHODS: Patients 18 years of age or older with anterior chamber cells grade 2 or higher on day 1 after uncomplicated cataract surgery were randomized to 14 days of treatment with LE gel 2 times a day, LE gel 3 times a day, or vehicle. Hierarchical primary endpoints were the proportion of patients with resolution of anterior chamber cells and grade 0 (no) pain at postoperative day 8. Safety outcomes included adverse events, intraocular pressure (IOP), biomicroscopy, visual acuity, ophthalmoscopy, and tolerability (drop comfort and ocular symptoms). RESULTS: The intent-to-treat population included 514 patients. Significantly more patients in the LE gel 2 times a day and 3 times a day groups compared with the vehicle group had complete resolution of anterior chamber cells (26.9% and 28.7% versus 9.3%) and reported grade 0 pain (73.7% and 73.1% versus 47.7%) on day 8 (P < .001 vs vehicle for all). The safety findings were unremarkable, with 1 patient experiencing an IOP increase of 10 mm Hg or higher while on LE gel. More than 75% of patients in each group reported no drop discomfort. CONCLUSION: In this study, submicron loteprednol etabonate gel 0.38% appeared safe and effective in the treatment of postoperative inflammation and pain whether instilled 2 times or 3 times a day.

Latanoprostene Bunod 0.024% in Subjects With Open-angle Glaucoma or Ocular Hypertension: Pooled Phase 3 Study Findings.

PURPOSE: To compare the diurnal intraocular pressure (IOP)-lowering effect of latanoprostene bunod (LBN) 0.024% with timolol maleate 0.5% in subjects with open-angle glaucoma (OAG) or ocular hypertension (OHT). PATIENTS AND METHODS: Pooled analysis of two phase 3, randomized, multicenter, double-masked, parallel-group, noninferiority trials (APOLLO and LUNAR), each with open-label safety extension phases. Adults with OAG or OHT were randomized 2:1 to double-masked treatment with LBN once daily (qd) or timolol twice daily (bid) for 3 months followed by open-label LBN treatment for 3 (LUNAR) or 9 (APOLLO) months. IOP was measured at 8 AM, 12 PM, and 4 PM at week 2, week 6, and months 3, 6, 9, and 12. RESULTS: Of the 840 subjects randomized, 774 (LBN, n=523; timolol crossover to LBN, n=251) completed the efficacy phase, and 738 completed the safety extension phase. Mean IOP was significantly lower with LBN versus timolol at all 9 evaluation timepoints during the efficacy phase (P<0.001). A significantly greater proportion of LBN-treated subjects attained a mean IOP ≤18 mm Hg and IOP reduction ≥25% from baseline versus timolol-treated subjects (P<0.001). The IOP reduction with LBN was sustained through the safety phase; subjects crossed over from timolol to LBN experienced additional significant IOP lowering (P≤0.009). Both treatments were well tolerated, and there were no safety concerns with long-term LBN treatment. CONCLUSIONS: In this pooled analysis of subjects with OAG and OHT, LBN 0.024% qd provided greater IOP-lowering compared with timolol 0.5% bid and maintained lowered IOP through 12 months. LBN demonstrated a safety profile comparable to that of prostaglandin analogs.

Efficacy of Latanoprostene Bunod 0.024% Compared With Timolol 0.5% in Lowering Intraocular Pressure Over 24 Hours.

PURPOSE: To compare the diurnal and nocturnal effects of latanoprostene bunod 0.024% solution with timolol maleate 0.5% solution on intraocular pressure (IOP) and ocular perfusion pressure. DESIGN: Prospective, open-label randomized crossover trial. METHODS: Twenty-five patients (aged 43-82 years) with ocular hypertension or early primary open-angle glaucoma were enrolled. Baseline IOP and blood pressure were measured in a sleep laboratory every 2 hours in the sitting and supine positions during the 16-hour diurnal/wake period and in the supine position during the 8-hour nocturnal/sleep period. Subjects were randomly assigned to bilateral treatments of latanoprostene bunod at 8 PM or timolol at 8 AM and 8 PM. The second laboratory recording occurred after the 4-week treatment. Subjects were crossed over to the comparator treatment for 4 weeks before the third laboratory recording. Mean IOP and calculated ocular perfusion pressure were compared for the diurnal and nocturnal periods. RESULTS: Twenty-one subjects completed the study. Both treatments reduced diurnal sitting and supine IOP compared to baseline by 2.3-3.9 mm Hg (all P < .001) with no statistically significant difference between the 2 treatments. Nocturnal IOP under latanoprostene bunod treatment was 2.5 ± 3.1 mm Hg (mean ± SD) less than baseline (P = .002) and 2.3 ± 3.0 mm Hg less than timolol treatment (P = .004). Latanoprostene bunod treatment resulted in greater diurnal sitting and supine ocular perfusion pressures compared with baseline (P ≤ .006) and greater nocturnal ocular perfusion pressure compared with timolol treatment (P = .010). CONCLUSIONS: During the nocturnal period, latanoprostene bunod caused more IOP reduction and more increase of ocular perfusion pressure than timolol.

Long-term Safety and Efficacy of Latanoprostene Bunod 0.024% in Japanese Subjects with Open-Angle Glaucoma or Ocular Hypertension: The JUPITER Study.

INTRODUCTION: Latanoprostene bunod (LBN) is a novel nitric oxide (NO)-donating prostaglandin F2α analog. We evaluated the long-term safety and intraocular pressure (IOP)-lowering efficacy of LBN ophthalmic solution 0.024% over 1 year in Japanese subjects with open-angle glaucoma (OAG) or ocular hypertension (OHT). METHODS: This was a single-arm, multicenter, open-label, clinical study. Subjects aged 20 years and older with a diagnosis of OAG or OHT instilled 1 drop of LBN ophthalmic solution 0.024% in the affected eye(s) once daily in the evening for 52 weeks and were evaluated every 4 weeks. Safety assessments included vital signs, comprehensive ophthalmic exams, and treatment-emergent adverse events (AEs). Absolute and percent reductions from baseline in IOP were also determined. RESULTS: Of 130 subjects enrolled, 121 (93.1%) completed the study. Mean age was 62.5 years, and mean (standard deviation) baseline IOP was 19.6 (2.9) and 18.7 (2.6) mmHg in study eyes and treated fellow eyes, respectively. Overall, 76/130 (58.5%) and 78/126 (61.9%) subjects experienced ≥1 AEs in study eyes and treated fellow eyes, respectively. In both study eyes and treated fellow eyes, the most common AEs were conjunctival hyperemia, growth of eyelashes, eye irritation, and eye pain. At 52 weeks, 9% of treated eyes had an increase in iris pigmentation compared with baseline based on iris photographs. No safety concerns emerged based on vital signs or other ocular assessments. Mean reductions from baseline in IOP of 22.0% and 19.5% were achieved by week 4 in study and treated fellow eyes, respectively. These reductions were maintained through week 52 (P < 0.001 vs. baseline at all visits). CONCLUSION: Once daily LBN ophthalmic solution 0.024% was safe and well-tolerated in Japanese subjects with OAG or OHT when used for up to 1 year. Long-term treatment with LBN ophthalmic solution 0.024% provided significant and sustained IOP reduction. TRIAL REGISTRATION: ClinicalTrials.gov identifier, NCT01895972. FUNDING: Bausch & Lomb, Inc. a division of Valeant Pharmaceuticals International Inc.

Comparison of Latanoprostene Bunod 0.024% and Timolol Maleate 0.5% in Open-Angle Glaucoma or Ocular Hypertension: The LUNAR Study.

PURPOSE: To compare the intraocular pressure (IOP)-lowering effect of latanoprostene bunod (LBN) 0.024% with timolol maleate 0.5% in subjects with open-angle glaucoma (OAG) or ocular hypertension (OHT). DESIGN: Prospective, randomized, double-masked, parallel-group, noninferiority clinical trial. METHODS: Adults with OAG or OHT from 46 clinical sites (United States and European Union) were randomized 2:1 to LBN instilled once daily (QD) in the evening and vehicle in the morning or timolol instilled twice a day (BID) for 3 months. IOP was measured at week 2, week 6, and month 3 (8 AM, 12 PM, and 4 PM each visit). RESULTS: A total of 387 subjects (LBN, n = 259; timolol, n = 128) completed the study. Analysis of covariance showed that mean IOP reduction with LBN was not only noninferior to timolol but significantly greater (P ≤ .025) than timolol at all but the first time point in this study (week 2, 8 AM). Of LBN- and timolol-treated subjects, respectively, 31.0% and 18.5% (P = .007) had their IOP reduced ≥25% from baseline, and 17.7% and 11.1% (P = .084) had their IOP reduced to ≤18 mm Hg over all time points/visits in this study. Ocular treatment-emergent adverse events, while uncommon, appeared more frequently in the LBN group (all mild-moderate except 1 case of severe hyperemia). CONCLUSIONS: LBN 0.024% QD in the evening was noninferior to timolol 0.5% BID over 3 months of treatment, with significantly greater IOP lowering in subjects with OAG or OHT at all but the earliest time point evaluated, and demonstrated a good safety profile.

A randomised, controlled comparison of latanoprostene bunod and latanoprost 0.005% in the treatment of ocular hypertension and open angle glaucoma: the VOYAGER study.

AIM: To assess the efficacy and safety of latanoprostene bunod (LBN) compared with latanoprost 0.005%, and to determine the optimum drug concentration(s) of LBN in reducing intraocular pressure (IOP) in subjects with open angle glaucoma or ocular hypertension. METHODS: Randomised, investigator-masked, parallel-group, dose-ranging study. Subjects instilled one drop of study medication in the study eye once daily each evening for 28 days and completed five study visits. The primary efficacy endpoint was the reduction in mean diurnal IOP at Day 28. RESULTS: Of the 413 subjects randomised (LBN 0.006%, n=82; LBN 0.012%, n=85; LBN 0.024%, n=83; LBN 0.040%, n=81; latanoprost, n=82), 396 subjects completed the study. Efficacy for LBN was dose-dependent reaching a plateau at 0.024%-0.040%. LBN 0.024% led to significantly greater reductions in diurnal IOP compared with latanoprost at the primary endpoint, Day 28 (p=0.005), as well as Days 7 (p=0.033) and 14 (p=0.015). The incidence of adverse events, mostly mild and transient, was numerically higher in the LBN treatment groups compared with the latanoprost group. Hyperaemia was similar across treatments. CONCLUSIONS: LBN 0.024% dosed once daily was the lower of the two most effective concentrations evaluated, with significantly greater IOP lowering and comparable side effects relative to latanoprost 0.005%. LBN dosed once daily for 28 days was well tolerated. CLINICAL TRIAL NUMBER: NCT01223378.

Latrunculin B Reduces Intraocular Pressure in Human Ocular Hypertension and Primary Open-Angle Glaucoma.

PURPOSE: To evaluate the safety, tolerability, and intraocular pressure (IOP)-lowering effect of Latrunculin-B (Lat-B), a marine macrolide that disrupts the actin cytoskeleton, in patients with ocular hypertension (OHT) or early primary open-angle glaucoma (POAG). METHODS: In this Phase I, multicenter, double-masked, randomized, placebo-controlled, ascending-dose study, subjects with bilateral OHT or early POAG (>22 mm Hg) received one of four concentrations of INS115644 (Lat-B ophthalmic solutions, 0.005%, 0.01%, 0.02%, or 0.05%) in one eye over 3 days (5 single-dose instillations, separated by 12 hours). One eye was randomly assigned to active drug, the other to placebo. IOP was measured prior to treatment initiation (day 0) and on days 1 and 3. RESULTS: Baseline IOPs were 22.9 ± 2.4 mm Hg and 23.5 + 3.1 mm Hg in the 0.02% and 0.05% dose groups, respectively. At 4 hours post instillation of the first dose, 0.02% INS115644 reduced IOP from baseline (mean ± SE) by 3.8 ± 0.7 mm Hg (P = 0.002) and 0.05% by 3.9 ± 1.0 mm Hg (P = 0.004). A maximum IOP decrease of 24% was noted at 4 hours after the fifth instillation of 0.02%. Adjusting for diurnal baseline and IOP in the contralateral, placebo-treated eye, the maximal 12-hour hypotensive effect was 4.0 ± 0.5 mm Hg (adjusted mean ± SE), a 17% decrease, following the fifth instillation of 0.02% (day 3). Adverse events were few and consisted mainly of mild redness, irritation, and a transient, clinically insignificant increase (≤2.5%) in central corneal thickness. CONCLUSIONS: In OHT or POAG patients, twice daily Lat-B significantly lowered IOP compared with contralateral, placebo-treated eyes, with few and mild ocular adverse events. TRANSLATIONAL RELEVANCE: Lat-B may be a potential therapeutic agent for glaucoma.

Nitric oxide (NO): an emerging target for the treatment of glaucoma.

The predominant risk factor for the progression of glaucoma is an increase in IOP, mediated via a reduction in aqueous outflow through the conventional (trabecular meshwork and Schlemm's canal) outflow pathway. Current IOP lowering pharmacological strategies target the uveoscleral (nonconventional) outflow pathway or aqueous humor production; however, to date no therapy that primarily targets the conventional pathway exists. Nitric oxide (NO) is an intracellular signaling molecule produced by endogenous NO synthases, well-known for its key role in vasodilation, through its action on smooth muscle cells. Under physiological conditions, NO mediates a multitude of diverse ocular effects, including maintenance of IOP. Nitric oxide donors have been shown to mediate IOP-lowering effects in both preclinical models and clinical studies, primarily through cell volume and contractility changes in the conventional outflow tissues. This review is focused on evaluating the current knowledge of the role and mechanism of action of endogenous NO and NO donors in IOP regulation. Data on key additional functions of NO in glaucoma pathology (i.e., ocular blood flow and effects on optic neuropathy) are also summarized. The potential for future therapeutic application of NO in the treatment of glaucoma is then discussed.

Caldesmon effects on the actin cytoskeleton and cell adhesion in cultured HTM cells.

Caldesmon is a multifunctional ubiquitous regulator of the actin cytoskeleton, which can affect both actomyosin contractility and actin polymerization. Previous studies showed that caldesmon over-expression in cultured fibroblasts produces effects that resemble those of chemical inhibitors of cellular contractility. Since these inhibitors (H-7, Y-27632, etc.) have been shown to lower intraocular pressure and increase outflow facility from the anterior chamber of the eye, we proposed that caldesmon might be used for gene therapy of glaucoma. In the present study we examined the effects of expression of adenovirus-delivered rat non-muscle caldesmon fused with green fluorescent protein (AdCaldGFP) on the actin cytoskeleton and matrix adhesions in cultured human trabecular meshwork (HTM) cells. In addition, we assessed the effect of caldesmon on the stability of cell-cell junctions in kidney epithelial MDCK cells. Cultured HTM cells demonstrate a well-developed actin cytoskeleton, comprising mainly arrays of parallel actomyosin bundles (stress fibers). Lamellipodial protrusions containing dense actin networks are also observed. Cell-matrix adhesions are dominated by focal adhesions (FAs) associated with the ends of the stress fibers, focal complexes in lamellipodia, and fibrillar adhesions in the central part of the spread cells. Treatment of HTM cells with AdCaldGFP resulted in dose-dependent morphological changes within 24-48 hr post-infection. Cells expressing moderate levels of caldesmon exhibited straight bundles containing actin and myosin II, which were considerably shorter than those in control cells. Short filament bundles in caldesmon over-expressing cells formed arrays consisting of triangular actin structures with small vinculin-positive FAs at their vertices. In addition, the fraction of cells displaying large lamellipodia increased. About 40-50% of the population of caldesmon-expressing cells demonstrated high levels of GFP-caldesmon expression and severe changes in the actin cytoskeleton, manifested by the disappearance of stress fibers and the formation of curved actin- and myosin-containing bundles. These bundles formed together a dynamic network consisting of pulsating loops filling the entire cytoplasm. Addition of thapsigargin, which increases intracellular Ca++ concentration, resulted in a straightening of the curved bundles. Another type of novel actin structures induced by caldesmon over-expression were highly dynamic circular waves that propagated over the affected cells with a velocity about 10 microm min. In cells with disrupted stress fibers, vinculin-containing FAs and tensin-rich fibrillar adhesions had also essentially vanished. However, phosphotyrosine-positive focal complexes were still prominent throughout the lamellipodia of these cells. Over-expression of caldesmon in MDCK cells reduced, in a dose dependent manner, the beta-catenin content at cell-cell adherens junctions and in some cases led to physical disruption of adherens junctions. Thus, caldesmon over-expression induces unique reorganization of the actin cytoskeleton in affected cells, accompanied by disruption of focal and fibrillar cell-matrix adhesions, and destabilization of cell-cell adherens junctions. Inducing such changes in the contractility and actin cytoskeleton of HTM cells in glaucomatous eyes in vivo could produce a therapeutically useful increase in outflow facility.

Caldesmon transgene expression disrupts focal adhesions in HTM cells and increases outflow facility in organ-cultured human and monkey anterior segments.

Cytoskeleton modulating compounds have been shown to lower intraocular pressure (IOP) and increase outflow facility. Caldesmon is one protein that is involved in the regulation of actin stress fiber formation. The effects of rat non-muscle caldesmon (Cald) gene over-expression on focal adhesions in human trabecular meshwork (HTM) cells and on outflow facility in organ-cultured human and monkey anterior segments were determined. Treatment of HTM cells with adenovirus-delivered caldesmon (AdCaldGFP) resulted in characteristic changes in the actin cytoskeleton and matrix adhesions within 24-48 hr post-transduction. Stress fibers gradually disappeared and novel actin structures were formed (see manuscript by Grosheva et al., this issue). In cells with disrupted stress fibers, vinculin-containing focal adhesions were also disrupted. In organ-cultured anterior segments, baseline outflow facility (microl min-1 mmHg-1) for all anterior segments averaged (mean+/-sem): human, 0.19+/-0.03 (n=12); monkey, 0.36+/-0.02 (n=19). In human anterior segments, transduction with 10(7) plaque forming units of AdGFPCald increased outflow facility by 43+/-21% (p

Gene transfer of dominant-negative RhoA increases outflow facility in perfused human anterior segment cultures.

PURPOSE: To investigate the regulation of expression and the role of the RhoA gene in the human trabecular meshwork (TM). To attempt to modulate outflow facility by gene transfer of the RhoA gene's dominant-negative mutant protein. METHODS: Total RNA extracted from cultured human trabecular meshwork (HTM) cells treated with outflow facility drugs were analyzed by northern blot hybridization using an amplified human RhoA cDNA from plasmid pZip-RhoA wild type (wt) [1]. A dominant-negative form of RhoA (single amino acid substitution of Thr19 to Asn) was placed under the control of the CMV promoter and inserted into a replication-deficient adenoviral vector by overlapping recombination (AdhRhoA2). AdhRhoA2 was infected into perfused anterior segment cultures from post-mortem human donors and HTM and Schlemm's canal cells in culture. Changes in outflow facility (flow/pressure) were calculated as percent changes from baseline values (C0), pooled into treated and control groups and expressed as the mean plus minus standard error. HTM and Schlemm's Canal (SC) cells were fluorescently double-labeled for the RhoA protein and actin, paxillin, or ZO-1. RESULTS: Transcription of RhoA in HTM cells was not considerably affected by treatment of the cells with cytoskeletal/outflow facility drugs. At 66 h post-injection, anterior segments treated with AdhRhoA2 (n=9) exhibited an increase in outflow facility of 32.5 +/- 7.7% while that of the vehicle-injected controls (n=6) was 5.1 +/- 4.0% (p=0.02). HTM cells treated with AdhRhoA2 showed a marked change in morphology with a reduction in actin stress fibers and of the focal adhesion-containing protein, paxillin. Confluent monolayers of SC cells infected with AdhRhoA2 were devoid of peripheral ZO-1 staining indicating a loss of intercellular junctions. CONCLUSIONS: In the HTM cells, cytoskeletal/outflow facility drugs do not seem to affect the levels of RhoA mRNA, possibly suggesting the importance of mRNA availability to allow rapid turnover of its function. Gene transfer of inactive RhoA to the intact human TM results in an increase in outflow facility. This increase appears to be correlated with a loosening of the cell-substrate and cell-cell attachments in the cells of the outflow pathway. Adenoviral vectors carrying the dominant negative form of RhoA could potentially be utilized as a gene therapy to modulate outflow facility.