Mechanism of action of bimatoprost, latanoprost, and travoprost in healthy subjects. A crossover study

NCX 470 Reduces Intraocular Pressure More Effectively Than Lumigan in Dogs and Enhances Conventional and Uveoscleral Outflow in Non-Human Primates and Human Trabecular Meshwork/Schlemm's Canal Constructs

Purpose: To determine NCX 470 (0.1%) and Lumigan® (bimatoprost ophthalmic solution, 0.01%-LUM) intraocular pressure (IOP)-lowering activity after single or repeated (5 days) dosing along with changes in aqueous humor (AH) dynamics. Methods: Ocular hypotensive activity of NCX 470 and LUM was compared with vehicle (VEH) in Beagle dogs using TonoVet®. Non-human primates (NHP) and bioengineered three-dimensional (3D) human Trabecular Meshwork/Schlemm's Canal (HTM/HSC™) constructs exposed to transforming growth factor-β2 (TGFβ2) were used to monitor NCX 470 and LUM-induced changes in AH dynamics. Results: NCX 470 (30 μL/eye) showed greater IOP reduction compared with LUM (30 μL/eye) following single AM dosing [maximum change from baseline (CFBmax) = -1.39 ± 0.52, -6.33 ± 0.73, and -3.89 ± 0.66 mmHg (mean ± standard error of the mean) for VEH, NCX 470, and LUM, respectively]. Likewise, repeated 5 days daily dosing of NCX 470 resulted in lower IOP than LUM across the duration of the study (average IOP decrease across tests was -0.45 ± 0.22, -6.06 ± 0.15, and -3.60 ± 0.22 mmHg for VEH, NCX 470, and LUM, respectively). NCX 470 increased outflow facility (Cfl) in vivo in NHP (CflVEH = 0.37 ± 0.09 μL/min/mmHg and CflNCX470 = 0.64 ± 0.17 μL/min/mmHg) as well as in vitro (CHTM/HSC) in HTM/HSC constructs (CHTM/HSC_VEH = 0.47 ± 0.02 μL/min/mm2/mmHg and CHTM/HSC_NCX470 = 0.76 ± 0.03 μL/min/mm2/mmHg). In addition, NCX 470 increased uveoscleral outflow (FuVEH = 0.62 ± 0.26 μL/min and FuNCX470 = 1.53 ± 0.39 μL/min with episcleral venous pressure of 15 mmHg) leaving unaltered aqueous flow (AHFVEH = 2.03 ± 0.22 μL/min and AHFNCX470 = 1.93 ± 0.31 μL/min) in NHP. Conclusions: NCX 470 elicits greater IOP reduction than LUM following single or repeated dosing. Data in NHP and 3D-HTM/HSC constructs suggest that changes in Cfl and Fu account for the robust IOP-lowering effect of NCX 470.

Selectively coated contact lenses by nanoelectrospray (nES) to fabricate drug-eluting contact lenses for treating ocular diseases

Drug-eluting contact lenses (DECLs) incorporated with poly(lactic-co-glycolic acid) (PLGA) and various model drugs (ketotifen fumarate, bimatoprost and latanoprost) were fabricated using nanoelectrospray (nES) approach. The resulting DECLs demonstrated outstanding optical transmittance within the optical zone, indicating that the employed coating procedure did not compromise visual acuity under the prescribed spraying parameters. In vitro drug release assessments of the model drugs (ketotifen fumarate (KF), bimatoprost (BIM), and latanoprost (LN)) revealed a strong correlation between the model drug's hydrophobicity and the duration of drug release. Changing the drug loading of the more hydrophilic model drugs, BIM and KF, showed no impact on the drug release kinetics of DECLs loaded with BIM and KF. However, for the hydrophobic model drug, LN, the highest LN loading led to the most extended drug release. The conventional steam sterilisation method was found to damage the PLGA coating on the DECLs fabricated by nES. An alternative sterilisation strategy, such as radiation sterilisation may need to be investigated in the future study to minimise potential harm to the coating.

Hypotony in uveitis: an overview of medical and surgical management

Hypotony is a well-recognised, sight-threatening complication of uveitis. It can also be the final common endpoint for a multitude of disease entities. Multiple mechanisms underlie hypotony, and meticulous clinical history alongside ocular phenotyping is necessary for choosing the best intervention and therapeutic management. In this narrative review, a comprehensive overview of medical and surgical treatment options for the management of non-surgically induced hypotony is provided. Management of ocular hypotony relies on the knowledge of the aetiology and mechanisms involved. An understanding of disease trajectory is vital to properly educate patients. Both anatomical and functional outcomes depend on the underlying pathophysiology and choice of treatment.

Safety and Efficacy of Prostaglandin Analogues in the Immediate Postoperative Period after Uneventful Phacoemulsification

Prostaglandin analogues (PGAs) have been associated with the development of pseudophakic macular edema (PME) in complicated cataract cases, but evidence on their effects in uncomplicated phacoemulsification remains controversial. This two-arm, prospective, randomised study included patients with glaucoma or ocular hypertension under PGA monotherapy who were scheduled for cataract surgery. The first group continued PGA use (PGA-on), while the second discontinued PGAs for the first postoperative month and reinitiated use afterwards (PGA-off). Topical non-steroidal anti-inflammatory drugs (NSAIDs) were routinely administered to all patients during the first postoperative month. The patients were followed up for three months and the primary outcome was PME development. Secondary outcomes were corrected distance visual acuity (CDVA), central and average macular thickness (CMT and AMT), and intraocular pressure (IOP). The analysis included 22 eyes in the PGA-on group and 33 eyes in the PGA-off group. No patient developed PME. CDVA was not significantly different between the two groups (p = 0.83). CMT and AMT showed a small but statistically significant increase until the end of follow-up (p < 0.001). Mean IOP values had no significant differences between the groups at each visit (p > 0.05). At the end of follow-up, the IOP values were significantly lower than baseline in both groups (p < 0.001). In conclusion, PGA administration with concomitant topical NSAIDs appears to be a safe practice in the early postoperative period of uncomplicated phacoemulsification.

Three Major Causes of Metabolic Retinal Degenerations and Three Ways to Avoid Them

An imbalance of homeostasis in the retina leads to neuron loss and this eventually results in a deterioration of vision. If the stress threshold is exceeded, different protective/survival mechanisms are activated. Numerous key molecular actors contribute to prevalent metabolically induced retinal diseases-the three major challenges are age-related alterations, diabetic retinopathy and glaucoma. These diseases have complex dysregulation of glucose-, lipid-, amino acid or purine metabolism. In this review, we summarize current knowledge on possible ways of preventing or circumventing retinal degeneration by available methods. We intend to provide a unified background, common prevention and treatment rationale for these disorders and identify the mechanisms through which these actions protect the retina. We suggest a role for herbal medicines, internal neuroprotective substances and synthetic drugs targeting four processes: parainflammation and/or glial cell activation, ischemia and related reactive oxygen species and vascular endothelial growth factor accumulation, apoptosis and/or autophagy of nerve cells and an elevation of ocular perfusion pressure and/or intraocular pressure. We conclude that in order to achieve substantial preventive or therapeutic effects, at least two of the mentioned pathways should be targeted synergistically. A repositioning of some drugs is considered to use them for the cure of the other related conditions.

Uses of eye drops in dermatology, literature review

Background: Since medication absorption through the skin and eye tissue seems similar, commercially available eye-drops could be used to treat skin diseases when topical therapies are unavailable or unaffordable. The FDA-approved and off-label applications of various eye drops used as topical treatments in dermatological clinical practice were highlighted in this review.Methodology: A thorough PubMed and Google Scholar library search using various combinations of the keywords (Eye drop, ocular solution, conjunctival installation, and skin diseases, topical, local, beta-blockers, prostaglandin, cyclosporin, apraclonidine, atropine, oxymetazoline).Results and conclusions: Based on the findings of the studies reviewed, timolol is highly recommended for infantile hemangioma and other vascular skin conditions such as angiomas, Kaposi sarcoma, acne, rosacea, and wound healing. Bimatoprost is a drug that can be used to treat hypotrichosis of any kind, as well as mild localized alopecia areata and leukoderma. Oxymetazoline ispromising for treating facial erythema. We recommend apraclonidine for mild upper eyelid ptosis induced botulinum neurotoxin. We don't recommend atropine for hyperhidrosis, although it can help with hydrocystomas and pruritis produced by syringomas. Tobramycin will need to be tested in RCTs before it can be confirmed as a viable alternative to systemic treatments for treating green nail syndrome.

Comparison of outflow facility before and after the microhook ab interno trabeculotomy

PURPOSES

To elucidate the mechanism of intraocular pressure (IOP) reduction by microhook ab interno trabeculotomy (μLOT), the aqueous humour outflow facility was compared preoperatively and post-operatively.

METHODS

Fifty-one eyes (37 patients; mean age, 67.2 ± 11.8 years) were included. The IOP, number of medications and outflow facility coefficient (C) estimated by pneumatonography were compared preoperatively and post-operatively using the paired t test. Linear regression analysis was performed to identify possible correlations between the C value and IOP or number of medications. To adjust for biases from including both eyes of a patient and differences in background, the preoperative and post-operative C values were compared using a mixed effects regression model.

RESULTS

The mean preoperative IOP (18.2 mmHg) and mean number of medications (2.8) decreased significantly post-operatively by 26% and 18%, respectively, to 13.5 mmHg and 2.3 (p < 0.0001, for both comparisons). The preoperative C value of 0.27 µl/min/mmHg increased significantly (p < 0.0001) by 89% to 0.51 µl/min/mmHg post-operatively. Linear regression analysis indicated that higher IOP was associated with lower C values (estimate, -0.01/mmHg, p = 0.0107); medication numbers were not associated with the C value (estimate, -0.04/medication, p = 0.1739). Mixed effects regression analysis showed that the post-operative measurement (estimate, 0.11/preoperative measurement, p < 0.0001) was associated with a higher C value, while age, sex, µLOT procedure, IOP and medication numbers were not.

CONCLUSION

Outflow facility assessed by the tonographic C value increased significantly after µLOT. Increased conventional outflow by elimination of the outflow resistance at the trabecular meshwork is the main mechanism of IOP reduction after µLOT.

Noninferiority Study Comparing Latanoprost 0.005% Without Versus With Benzalkonium Chloride in Open-Angle Glaucoma or Ocular Hypertension

OBJECTIVES

To evaluate the noninferiority of intraocular pressure (IOP)-lowering latanoprost without benzalkonium chloride (BAK) versus latanoprost with BAK (for treatment of open-angle glaucoma or ocular hypertension).

METHODS

Overall, 578 patients were randomized 1:1 to latanoprost without BAK or latanoprost with BAK once daily in the affected eye(s) for 12 weeks. The primary efficacy endpoint was IOP, measured on days 0, 7, 28, 56, and 84 (8 am, 10 am, and 4 pm). Noninferiority was established if the following criteria were met: 95% confidence interval (CI) of the mean difference between treatments included 0 mm Hg for all time points (N1), 95% CI upper limit less than 1.5 mm Hg (N2), and less than 1 mm Hg for≥7 of 12 time points (N3). Primary efficacy analysis was performed on the intent-to-treat population. Safety measurements included ocular and systemic adverse event (AE).

RESULTS

The 95% CI included 0 mm Hg for 7/12 time points (N1), 95% CI upper limit was less than 1.5 mm Hg for 12/12 time points (N2), and less than 1.0 mm Hg for 4/7 time points (N3). AEs were mild and similarly distributed between groups.

CONCLUSIONS

Latanoprost without BAK did not meet two of three criteria for noninferiority and showed a similar safety profile relative to latanoprost with BAK.

Comparison of the Drug-Induced Efficacies between Omidenepag Isopropyl, an EP2 Agonist and PGF2α toward TGF-β2-Modulated Human Trabecular Meshwork (HTM) Cells

To compare the drug-induced efficacies between omidenepag (OMD), an EP2 agonist, and prostaglandin F2α (PGF2α) on glaucomatous trabecular meshwork (TM) cells, two- and three-dimensional (2D and 3D) cultures of TGF-β2-modulated human trabecular meshwork (HTM) cells were used. The following analyses were performed: (1) transendothelial electrical resistance (TEER) and FITC-dextran permeability measurements (2D), (2) the size and stiffness of the 3D spheroids, and (3) the expression (both 2D and 3D) by several extracellular matrix (ECM) molecules including collagen (COL) 1, 4 and 6, and fibronectin (FN), and α smooth muscle actin (αSMA), tight junction (TJ)-related molecules, claudin11 (Cldn11) and ZO1, the tissue inhibitor of metalloproteinase (TIMP) 1–4, matrix metalloproteinase (MMP) 2, 9 and 14, connective tissue growth factor (CTGF), and several endoplasmic reticulum (ER) stress-related factors. TGF-β2 significantly increased the TEER values and decreased FITC-dextran permeability, respectively, in the 2D HTM monolayers, and induced the formation of downsized and stiffer 3D HTM spheroids. TGF-β2-induced changes in TEER levels and FITC-dextran permeability were remarkably inhibited by PGF2α. PGF2α induced increases in the sizes and stiffness of the TGF-β2-treated 3D spheroids, but OMD enhanced only spheroid size. Upon exposure to TGF-β2, the expression of most of the molecules that were evaluated were significantly up-regulated, except some of ER stress-related factors were down-regulated. TJ-related molecules or ER stress-related factors were significantly up-regulated (2D) or down-regulated (3D), and down-regulated (2D) by PGF2α and OMD, while both drugs altered the expression of some of the other genes in the 3D spheroids in a different manner. The findings presented herein suggest that PGF2α and OMD differently modulate the permeability of the TGFβ2-modulated 2D monolayers and the physical properties of the 3D HTM spheroids.

The Roles Played by FP/EP3 Receptors During Pressure-lowering in Mouse Eyes Mediated by a Dual FP/EP3 Receptor Agonist

Purpose

We investigated the intraocular pressure (IOP)-lowering effect of topical sepetaprost (SPT), a dual agonist of the FP and EP3 receptors. We explored whether certain receptors mediated the hypotensive effect of SPT and outflow facility changes in C57BL/6 mice (wild-type [WT]) and FP and EP3 receptor-deficient mice (FPKO and EP3KO mice, respectively).

Methods

IOP was measured using a microneedle. Outflow facility was measured using a two-level, constant-pressure perfusion method.

Results

SPT significantly reduced IOP for 8 hours after administration to WT mice. The 2-hour IOP reductions afforded by latanoprost were 15.3 ± 2.5, 1.8 ± 2.0, and 12.3 ± 2.4% in WT, FPKO, and EP3KO mice, respectively; the SPT figures were 13.6 ± 2.1, 5.9 ± 2.7, and 6.6 ± 2.6%, respectively. Latanoprost-mediated IOP reduction was significantly decreased in FPKO mice, and SPT-mediated IOP reduction was reduced in both FPKO and EP3KO mice. At 6 hours after administration, latanoprost did not significantly reduce the IOP in any tested mouse strain. SPT-mediated IOP reduction was reduced in both FPKO and EP3KO mice. IOP reduction at 6 hours was significantly higher after simultaneous administration of selective FP and EP3 receptor agonists, but IOP did not fall on administration of (only) a selective EP3 receptor agonist. SPT significantly increased outflow facility in WT mice, but less so in FPKO and EP3KO mice.

Conclusions

The IOP-lowering effect of SPT lasted longer than that of latanoprost. Our data imply that this may be attributable to augmented outflow facility mediated by the FP and EP3 receptors.

Screening of the Drug-Induced Effects of Prostaglandin EP2 and FP Agonists on 3D Cultures of Dexamethasone-Treated Human Trabecular Meshwork Cells

The objective of the current study was to perform a screening of the drug-induced effects of the prostaglandin F2α (PGF2α) and EP2 agonist, omidenepag (OMD), using two- and three-dimensional (2D and 3D) cultures of dexamethasone (DEX)-treated human trabecular meshwork (HTM) cells. The drug-induced effects on 2D monolayers were characterized by measuring the transendothelial electrical resistance (TEER) and fluorescein isothiocyanate (FITC)–dextran permeability, the physical properties of 3D spheroids, and the gene expression of extracellular matrix (ECM) molecules, including collagen (COL) 1, 4 and 6, and fibronectin (FN), α smooth muscle actin (αSMA), a tissue inhibitor of metalloproteinase (TIMP) 1–4, matrix metalloproteinase (MMP) 2, 9 and 14 and endoplasmic reticulum (ER) stress-related factors. DEX induced a significant increase in TEER values and a decrease in FITC–dextran permeability, respectively, in the 2D HTM monolayers, and these effects were substantially inhibited by PGF2α and OMD. Similarly, DEX also caused decreased sizes and an increased stiffness in the 3D HTM spheroids, but PGF2α or OMD had no effects on the stiffness of the spheroids. Upon exposure to DEX, the following changes were observed: the upregulation of COL4 (2D), αSMA (2D), and TIMP4 (2D and 3D) and the downregulation of TIMP1 and 2 (3D), MMP2 and 14 (3D), inositol-requiring enzyme 1 (IRE1), activating transcription factor 6 (ATF6) (2D), and glucose regulator protein (GRP)78 (3D). In the presence of PGF2α or OMD, the downregulation of COL4 (2D), FN (3D), αSMA (2D), TIMP3 (3D), MMP9 (3D) and the CCAAT/enhancer-binding protein homologous protein (CHOP) (2D), and the upregulation of TIMP4 (2D and 3D), MMP2, 9 and 14 (2D), respectively, were observed. The findings presented herein suggest that 2D and 3D cell cultures can be useful in screening for the drug-induced effects of PGF2α and OMD toward DEX-treated HTM cells.

Long-Term Effectiveness and Safety of Tafluprost, Travoprost, and Latanoprost in Korean Patients with Primary Open-Angle Glaucoma or Normal-Tension Glaucoma: A Multicenter Retrospective Cohort Study (LOTUS Study)

This multicenter retrospective cohort study compared the effectiveness and safety of long-term tafluprost, travoprost, or latanoprost in patients with primary open-angle glaucoma (POAG) or normal-tension glaucoma (NTG). Data were extracted from electronic medical records of 300 patients treated with tafluprost, travoprost, or latanoprost for >6 months. Propensity matching for age and sex was used for effectiveness and safety comparisons. The primary endpoint was visual field (VF) progression via mean deviation (MD) slope. Secondary endpoints were change of MD, intraocular pressure, pattern standard deviation, VF index, and advanced glaucoma intervention study score. Treatment-related adverse events (AEs) were also compared between groups. Overall, 216 POAG or NTG patients were matched into Match Set 1 (72 patients/group), and 177 NTG-only patients in Match Set 2 (59 patients/group) according to: age (mean: 61, 62 years) and sex (male: 53, 56%). There were no statistically significant between-group differences regarding MD slope (p = 0.413, p = 0.374 in Match Sets 1 and 2, respectively). There were no significant between-group differences/tendencies regarding secondary endpoints. No AEs were serious, and there were no significant between-group differences regarding reported AEs. In patients with POAG or NTG, long-term tafluprost, travoprost, or latanoprost showed similar effects. All three prostaglandin analogs had good long-term safety profiles.

Effect of prostaglandin analogues on anterior scleral thickness and corneal thickness in patients with primary open-angle glaucoma

Prostaglandin (PG) analogues are usually prescribed as a first-line therapy in patients with glaucoma because of its once-daily dosing benefit and effective intraocular pressure (IOP) reduction. However, the mechanism of PG analogues is not completely understood. In this study, we investigated the effect of PG analogues on the anterior scleral thickness (AST) in treatment-naïve eyes with primary open-angle glaucoma using anterior segment optical coherence tomography. The AST was measured at the location of the scleral spur, 1000 μm, and 2000 μm posterior to the scleral spur and was compared before and after using the medications for 3 months and 1 year. Among 54 patients enrolled in this study, 31 patients used prostaglandin analogues and 23 patients used dorzolamide/timolol fixed combination (DTFC) drugs. There was no significant difference in untreated IOP, glaucoma severity, and baseline AST values between the two groups. While there was no significant changes in AST after using the DTFC drugs, the AST at all 3 locations showed a significant reduction in both the nasal and temporal sectors after using PG analogues for 1 year (all, P < 0.05). These findings suggest that the AST reduction after using PG analogues might be related with the increased uveoscleral outflow.

Prostaglandin F2α agonists induced enhancement in collagen1 expression is involved in the pathogenesis of the deepening of upper eyelid sulcus

Previous our study reported that three-dimension (3D) cultures of human orbital fibroblasts (HOFs) replicated the etiology of deepening of the upper eyelid sulcus (DUES) caused by prostaglandin F2α analogues (PGF2α-ags). To examine this further, the effects of PGF2α-ags on HOFs were characterized by (1) lipid staining (2D; two-dimension, 3D), (2) comparison of the 3D organoid sizes of preadipocytes (DIF-) or adipocytes (DIF+) that had been treated with various concentrations of several PGF2α-ags, (3) physical stiffness (3D), and (4) the mRNA expression of adipogenic related genes, extracellular matrix (ECM), tissue inhibitors of metalloproteinases (TIMPs) and matrix metalloproteinases (MMPs) (3D). PGF2α-ags caused a dramatic down-sizing of the 3D DIF+ organoids and this reduction was concentration dependent. The effects caused by PGF2α-ags were also observed in 3D preadipocytes. Micro-squeezer analysis clearly indicated that PGF2α-ags induced an increase in their physical solidity. The size of each organoid under several conditions was inversely correlated with the mRNA expression profile of collagen1 (COL1), TIMP2, and MMP2 and 9. These findings indicate that PGF2α-ags affect the expression of COL1, TIMP2, and MMP2 and 9 which, in turn, modulate the 3D ECM network within the organoids, thus resulting in their downsizing.

Pharmacokinetics and Pharmacology of Latanoprost 0.005% without Benzalkonium Chloride Vs Latanoprost 0.005% with Benzalkonium Chloride in New Zealand White Rabbits and Beagles

Purpose: Many intraocular pressure (IOP)-lowering medications contain benzalkonium chloride (BAK), a preservative associated with unfavorable outcomes.A formulation of latanoprost 0.005% ophthalmic without BAK is approved by the FDA and indicated for reduction of IOP in patients with open-angle glaucoma or ocular hypertension. We present two preclinical studies of latanoprost 0.005% BAK-free vs latanoprost with BAK; one examining plasma and ocular tissue pharmacokinetics (PK) in New Zealand white rabbits, and one comparing in vivo IOP-lowering efficacy in healthy beagles.Methods: In the PK study, one drop of treatment (latanoprost BAK-free or latanoprost with BAK) was instilled into both eyes of rabbits in each treatment group (n = 18). At 0.25, 0.5, 1, 4, 6, and 24 hours postdose, three rabbits per study group underwent terminal blood and tissue collection.In the IOP study, in the first dosing period, both eyes of each beagle received either 1 drop latanoprost BAK-free or latanoprost with BAK, once daily for 10 days. After a 10-day washout period, a second 10-day dosing period was conducted and latanoprost BAK-free or latanoprost with BAK were dosed in the opposite eyes, respectively. IOP measurements were taken at 1, 6, and 12 hours postdose.Results: The maximum plasma concentration for latanoprost BAK-free and latanoprost with BAK occurred 0.25 hours after administration (174.1 vs 217.2 pg/mL, respectively). Area under the concentration time curve from zero to infinity was highest in aqueous humor for latanoprost BAK-free and latanoprost with BAK (133.1 vs 119.6 hr·ng/mL, respectively) and was not estimable in vitreous humor. In beagles, once-daily administration of latanoprost BAK-free or latanoprost with BAK led to a significant reduction in IOP vs baseline (P < .001); there was no difference between groups (P > .05).Conclusions: Latanoprost BAK-free showed comparable activity in reducing IOP, and comparable plasma and ocular PK parameters to latanoprost with BAK.

Discovery to Launch of Anti-allergy (Emadine; Patanol/Pataday/Pazeo) and Anti-glaucoma (Travatan; Simbrinza) Ocular Drugs, and Generation of Novel Pharmacological Tools Such as AL-8810

The eye and eyesight are exquistly designed and are precious, and yet we often take them for granted. Good vision is critical for our long-term survival and for humanity's enduring progress. Unfortunately, since ocular diseases do not culminate in life-and-death scenarios, awareness of the plight of millions of people suffering from such eye ailments is not publicized as other diseases. However, losing eyesight or falling victim to visual impairment is a frightening outlook for most people. Glaucoma, a collection of chronic optic neuropathies, of which the most prevalent form, primary open-angle glaucoma (POAG), is the second leading cause of irreversible blindness. POAG currently afflicts >70 million people worldwide and is an insidious, progressive, silent thief of sight that is asymptomatic. On the other hand, allergic conjunctivitis (AC), and the associated rhinitis ("hay-fever"), frequently victimizes a huge number of people worldwide, especially during seasonal changes. While not life-threatening, sufferers of AC soon learn the value of drugs to treat their signs and symptoms of AC as they desire rapid relief to overcome the ocular itching/pain, redness, and tearing AC causes. Herein, I will describe the collective efforts of many researchers whose industrious, diligent, and dedicated team work resulted in the discovery, biochemical/pharmacological characterization, development and eventual launch of drugs to treat AC (e.g., olopatadine [Patanol/Pataday/Pazeo] and emedastine [Emedine]), and for treating ocular hypertension and POAG (e.g., travoprost [Travatan ] and Simbrinza). This represents a personal perspective.

Effect of surfactant concentration and sterilization process on intraocular pressure-lowering activity of Δ9-tetrahydrocannabinol-valine-hemisuccinate (NB1111) nanoemulsions

The use of Δ⁹-tetrahydrocannabinol (THC) and Δ⁹-tetrahydrocannabinol-valine-hemisuccinate (THC-VHS; NB1111) has recently been investigated in the management of intraocular pressure (IOP). The current study was undertaken to develop an optimized THC-VHS-loaded nanoemulsion formulation (NE; THC-VHS-NE) that could improve the drug load and duration of activity. THC-VHS-NE formulation was prepared by homogenization followed by ultrasonication. Sesame oil, Tween®80, and Poloxamer®188 were used as the oil, surfactant, and cosurfactant, respectively. Stability of the optimized THC-VHS-NE formulation was observed at 4 °C. The IOP lowering effect of the lead formulations, commercial timolol, and latanoprost ophthalmic solutions, as well as an emulsion in Tocrisolve™ (THC-VHS-TOC), was studied in New Zealand White rabbits following topical administration. The effect of surfactant concentration and sterilization process on IOP-lowering activity was also studied. THC-VHS-NE formulations (0.5, 1.0, and 2.0% w/v) showed dose dependent duration of action. The 1.0%w/v THC-VHS-NE formulation was selected for further evaluation because of its desirable physical and chemical characteristics. THC-VHS-NE formulation prepared with 2% w/v Tween®80 exhibited a higher drop in IOP than the 0.75 and 4.0% w/v of Tween®80 containing formulations. The IOP-lowering duration was, however, similar for the formulations with 0.75 and 2.0% Tween®80, while that with 4.0% Tween®80 was shorter. THC-VHS-NE formulation produced a greater drop in IOP (p < 0.05) and a longer duration of activity compared to THC-VHS-TOC, latanoprost, and timolol. The formulation could be sterilized by filtration without impacting product attributes. Overall, the optimized THC-VHS-NE formulation demonstrated a significantly better IOP reduction profile in the test model compared to the commercial ophthalmic solutions evaluated.

Physiochemical Properties and Cytotoxicity of a Benzalkonium Chloride-Free, Micellar Emulsion Ophthalmic Formulation of Latanoprost

Purpose

Prostaglandin derivatives are used widely to reduce intraocular pressure associated with open-angle glaucoma. The most widely used prostaglandin derivative, latanoprost, is available in an ophthalmic solution that is solubilized and preserved with 0.02% benzalkonium chloride (BAK), which has been shown to be cytotoxic to corneal cells. Latanoprost ophthalmic solution with BAK requires specific storage temperatures, which can impact the supply cycle. Here, we describe the production, physicochemical characteristics, and cytotoxicity profile of a micelle formulation that solubilizes latanoprost without the need for BAK.

Methods

The optimum concentration of castor oil with the surfactant polyethylene glycol (15) hydroxystearate was determined, and the mixture stirred. Various surfactants were tested to determine the ideal mixture to form a micelle formulation. Viscosity, zeta potential, surface tension, droplet size, and osmolality of the batches were tested. The cytotoxicity of the micelle formulation was determined in a corneal cell viability assay that compared positive and negative controls, latanoprost without BAK, latanoprost with BAK, and placebo.

Results

A castor oil concentration of 0.15% produced a micelle formulation with a diameter of <100 nm. This micelle formulation had unique characteristics that were not mimicked when either the surfactant or the oil was changed. The physicochemical characteristics in multiple batches of the micelle formulation did not vary significantly between batches. Long-term and accelerated stability studies showed latanoprost potency remained constant for 24 months at 25°C/75% relative humidity (RH) and at 40°C/25% RH for 6 months.

Conclusion

The micelle formulation technology system is capable of solubilizing latanoprost in an ophthalmic formulation without the need for BAK. The system is stable at room temperature.

24-Month Phase I/II Clinical Trial of Bimatoprost Sustained-Release Implant (Bimatoprost SR) in Glaucoma Patients

Objective

The objective of this study was to evaluate the safety and intraocular pressure (IOP)-lowering effects over 24 months of biodegradable bimatoprost sustained-release implant (Bimatoprost SR) administration versus topical bimatoprost 0.03% in patients with open-angle glaucoma (OAG).

Methods

This was a phase I/II, prospective, 24-month, dose-ranging, paired-eye controlled clinical trial. At baseline following washout, adult patients with OAG (N = 75) received Bimatoprost SR (6, 10, 15, or 20 µg) intracamerally in the study eye; the fellow eye received topical bimatoprost 0.03% once daily. Rescue topical IOP-lowering medication or single repeat administration with implant was permitted. The primary endpoint was IOP change from baseline. Safety measures included adverse events (AEs).

Results

At month 24, mean IOP reduction from baseline was 7.5, 7.3, 7.3, and 8.9 mmHg in eyes treated with Bimatoprost SR 6, 10, 15, and 20 µg, respectively, versus 8.2 mmHg in pooled fellow eyes; 68, 40, and 28% of pooled study eyes had not been rescued/retreated at months 6, 12, and 24, respectively. AEs in study eyes that occurred ≤ 2 days post-procedure typically were transient. After 2 days post-procedure, overall AE incidence was similar between study and fellow eyes, with some events typically associated with topical prostaglandin analogs having lower incidence in study eyes.

Conclusions

Bimatoprost SR showed favorable efficacy and safety profiles up to 24 months, with all evaluated dose strengths demonstrating overall IOP-reducing effects comparable to those of topical bimatoprost. Targeted and sustained delivery of bimatoprost resulted in protracted IOP lowering, suggesting that Bimatoprost SR may represent a transformational new approach to glaucoma therapy. Clinicaltrials.gov identifier: NCT01157364

Electronic supplementary material

The online version of this article (10.1007/s40265-019-01248-0) contains supplementary material, which is available to authorized users.

Effects of Topical Prostaglandin Analog on Macular Thickness Following Cataract Surgery with Postoperative Topical Bromfenac Treatment

Purpose: To evaluate changes in macular thickness in patients continuing prostaglandin analog (PGA) treatment during the perioperative period involving bromfenac treatment. Methods: Patients with glaucoma who were using a topical PGA were randomly assigned to two groups in this randomized controlled trial: PGA continuing study group and PGA discontinued glaucoma control group. Patients without ocular diseases other than cataract were enrolled into the non-glaucomatous group. After the cataract surgery, the patients used bromfenac twice per day for 4 weeks. Optical coherence tomography was performed in all patients preoperatively and at 1 month postoperatively. Changes in macular thickness were compared among the three groups. Results: There were 32 eyes in the study group, 33 eyes in the glaucoma control group, and 58 eyes in the non-glaucomatous group. We found statistically significant postoperative changes in central macular thickness in all groups (4.30 ± 8.01 μm in the PGA continuing group, 9.20 ± 13.88 μm in the PGA discontinued group, and 7.06 ± 7.02 μm in the non-glaucomatous group, all p < 0.008), but no significant difference among the three groups (p = 0.161). Cystoid macular edema occurred in only one patient in the non-glaucomatous group (p = 0.568). Conclusions: Continuous use of PGAs during the perioperative period was not significantly associated with increased macular thickness after uncomplicated cataract surgery. In the absence of other risk factors (e.g., capsular rupture, uveitis, or diabetic retinopathy), discontinuing PGAs for the prevention of macular edema after cataract surgery with postoperative bromfenac treatment is unnecessary in patients with glaucoma.

Uveitis-induced Refractory Ocular Hypotony Managed with High-dose Latanoprost

Purpose

To report a case of refractory ocular hypotony due to chronic Behcet's disease with good response to high-dose topical latanoprost.

Case Report

We present a 26-year-old man with a known history of Behcet's disease who developed decreasing vision and severe ocular hypotony that was refractory to multiple treatment modalities including subtenon triamcinolone acetonide, ibopamine, pars plana vitrectomy, and silicone oil injection. We decided to try high-dose topical latanoprost for the management of ocular hypotony based on recent reports. After six months, intraocular pressure (IOP) increased by 5 mm Hg, became stable at 7 mm Hg, and remained unchanged at month 24.

Conclusion

High-dose topical latanoprost could lead to significant increase in IOP in uveitis-induced refractory ocular hypotony.

Uveitis and cystoid macular oedema secondary to topical prostaglandin analogue use in ocular hypertension and open angle glaucoma

BACKGROUND

Of the side effects of prostaglandin analogues (PGAs), uveitis and cystoid macular oedema (CME) have significant potential for vision loss based on postmarket reports. Caution has been advised due to concerns of macular oedema and uveitis. In this report, we researched and summarised the original data suggesting these effects and determined their incidence.

METHODS

Preferred Reporting Items for Systematic review and Meta-Analyses guidelines were followed. Studies evaluating topical PGAs in patients with ocular hypertension or open angle glaucoma were included. MEDLINE, PubMed, EMBASE, CINAHL, Web of Science, Cochrane Library, LILACS and ClinicalTrials.gov were searched between 1946 and 2019. Experimental studies, animal studies and randomised studies with other intraocular pressure-lowering eye drops were excluded.

RESULTS

214 studies (28 232 patients) met the inclusion criteria. Using prospective data, the incidence of uveitis and CME among PGA users were 62/28 232 (0.22%) and 25/28 232 (0.09%), respectively. A higher frequency of both uveitis and CME were found among latanoprost users compared with bimatoprost. There were 21 case studies reporting CME including 48 eyes in 43 patients. 47 of 48 eyes (97.9%) had previous incisional ocular surgery. 8 eyes were re-challenged, of which 7 (87.5%) recurred. 7 case studies reported uveitis in 15 eyes of 10 patients. 7 of 15 eyes (46.7%) were either pseudophakic or aphakic. 6 eyes were re-challenged, and all 6 (100%) recurred.

CONCLUSIONS

Cases of uveitis or CME revealed a confounding effect of ocular surgery, aphakia or subluxed intraocular lens. PGAs may be used in non-surgical patients without concern of causing CME or uveitis. The incidences of PGA-associated CME and uveitis are rare with limited prospective studies on the cause-effect relationship.

The Effect of High-Intensity Focused Ultrasound on Aqueous Humor Dynamics in Patients with Glaucoma

PURPOSE

To investigate the effects of high-intensity focused ultrasound (HiFU) on aqueous humor dynamics in patients with glaucoma.

DESIGN

Comparative, nonrandomized, interventional study.

PARTICIPANTS

Adult patients with a diagnosis of open-angle glaucoma or ocular hypertension with suboptimal intraocular pressure (IOP) control despite maximum medical treatment who required further IOP optimization.

METHODS

All patients underwent comprehensive ophthalmic examination before aqueous humor dynamics study measurements, including fluorophotometry and digital Schiøtz tonography. All patients received 6 seconds of HiFU therapy. Aqueous humor dynamics studies were repeated 3 months after the treatment (patients had 4-week washout from their glaucoma medication before their aqueous humor dynamics study measurements at baseline and the 3-month visit).

MAIN OUTCOME MEASURES

Intraocular pressure, facility of topographic outflow, aqueous flow rate, and uveoscleral outflow.

RESULTS

Thirty eyes of 30 patients were included in the study. At the 3-month postoperative visit, the mean postwashout IOP was reduced by 16% (31.7±5.3 vs. 26.6±4.8 mmHg, P = 0.004), and aqueous flow rate was decreased by 15% (2.07±0.73 vs. 1.77±0.55 μl/min, P = 0.05) from baseline. Neither the tonographic outflow facility nor the uveoscleral outflow was significantly different from baseline. There is a 20% risk of treatment failure (those who needed further glaucoma surgical intervention) within 1 month after a single HiFU treatment (n = 6). Only 25 patients (80%) were able to undergo post-treatment washout measurements, and in these eyes, only 26.6% of eyes achieved >20% IOP reduction at 3 months compared with baseline.

CONCLUSIONS

We investigated the aqueous humor dynamics effects of a cyclodestructive procedure and specifically HiFU in patients with uncontrolled open-angle glaucoma on maximum tolerated medical therapy. High-intensity focused ultrasound reduced IOP 3 months postoperatively by 16% and aqueous flow decreased by 15% without any significant effect on tonographic outflow facility and uveoscleral outflow.

Matrix Metalloproteinases and Glaucoma Treatment

Matrix metalloproteinases (MMPs) are a family of proteolytic enzymes that degrade extracellular matrix (ECM) components such as collagen and have important roles in multiple biological processes, including development and tissue remodeling, both in health and disease. The activity of MMPs is influenced by the expression of MMPs and tissue inhibitors of metalloproteinase (TIMPs). In the eye, MMP-mediated ECM turnover in the juxtacanalicular region of the trabecular meshwork (TM) reduces outflow resistance in the conventional outflow pathway and helps maintain intraocular pressure (IOP) homeostasis. An imbalance in the MMP/TIMP ratio may be involved in the elevated IOP often associated with glaucoma. The prostaglandin analog/prostamide (PGA) class of topical ocular hypotensive medications used in glaucoma treatment reduces IOP by increasing outflow through both conventional and unconventional (uveoscleral) outflow pathways. Evidence from in vivo and in vitro studies using animal models and anterior segment explant and cell cultures indicates that the mechanism of IOP lowering by PGAs involves increased MMP expression in the TM and ciliary body, leading to tissue remodeling that enhances conventional and unconventional outflow. PGA effects on MMP expression are dependent on the identity and concentration of the PGA. An intracameral sustained-release PGA implant (Bimatoprost SR) in development for glaucoma treatment can reduce IOP for many months after expected intraocular drug bioavailability. We hypothesize that the higher concentrations of bimatoprost achieved in ocular outflow tissues with the implant produce greater MMP upregulation and more extensive, sustained MMP-mediated target tissue remodeling, providing an extended duration of effect.

Effect of prostaglandin analogs: Latanoprost, bimatoprost, and unoprostone on matrix metalloproteinases and their inhibitors in human trabecular meshwork endothelial cells

Bimatoprost, latanoprost, and unoprostone are prostaglandin F_2α analogs (PGAs) and are used to lower intraocular pressure. We investigated the free acid effects of these three prostaglandin analogs: bimatoprost, latanoprost, and unoprostone on human matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMP) in the trabecular meshwork (TM) cells. Immunoblot results show that all three PGAs generally increased MMPs-1,9 and TIMPs-4. Additionally, bimatoprost and latanoprost both increased MMP-3 and TIMP-2, while unoprostone had an indeterminate effect on both. Zymography results show that all three PGAs except unoprostone increased intermediate MMP-1 activity while bimatoprost and latanoprost increased MMP-9 activity. Together, these data suggest that the balance between MMPs and TIMPs correlate to the relative intraocular pressure lowering effectiveness observed in clinical studies of these PGAs.

Recent Research on the Health Benefits of Blueberries and Their Anthocyanins

Awareness of the human health benefits of blueberries is underpinned by a growing body of positive scientific evidence from human observational and clinical research, plus mechanistic research using animal and in vitro models. Blueberries contain a large number of phytochemicals, including abundant anthocyanin pigments. Of their various phytochemicals, anthocyanins probably make the greatest impact on blueberry health functionality. Epidemiological studies associate regular, moderate intake of blueberries and/or anthocyanins with reduced risk of cardiovascular disease, death, and type 2 diabetes, and with improved weight maintenance and neuroprotection. These findings are supported by biomarker-based evidence from human clinical studies. Among the more important healthful aspects of blueberries are their anti-inflammatory and antioxidant actions and their beneficial effects on vascular and glucoregulatory function. Blueberry phytochemicals may affect gastrointestinal microflora and contribute to host health. These aspects have implications in degenerative diseases and conditions as well as the aging process. More evidence, and particularly human clinical evidence, is needed to better understand the potential for anthocyanin-rich blueberries to benefit public health. However, it is widely agreed that the regular consumption of tasty, ripe blueberries can be unconditionally recommended.

Predictors of selective laser trabeculoplasty success in open angle glaucoma or ocular hypertension: does baseline tonography have a predictive role?

Background

The determinants of success of selective laser trabeculoplasty (SLT) in treatment-naïve patients with open angle glaucoma (OAG) and ocular hypertension (OHT) have not been understood fully. Therefore, we have conducted this study to explore the predictors of success.

Methods

This is a retrospective review of a pre-existing database of patients who had received primary SLT at St Thomas’ Hospital, London, UK. Patients with OAG and OHT who had received primary 360° SLT treatment and had reliable baseline tonographic outflow facility (TOF) with minimum of 1 year of follow-up were included. Univariate and multivariate analyses were performed to find the determinants of success.

Results

One hundred and seventy-four patients between August 2006 and February 2010 had received primary 360° SLT treatment and had baseline TOF measurement. Of these, 72 subjects fulfilled the eligibility criteria. In multivariate regression analysis, the only variable associated with success was baseline intraocular pressure (IOP) (R2=0.32, beta=−0.51, p<0.001, 95% CI −2.02 to −0.74).

Conclusion

To our knowledge, this is the only study investigating the pretreatment TOF (measured with electronic Shiøtz tonography) and IOP as determinants of success 12 month’s post-360° SLT in treatment-naïve patients with OAG and OHT. This study demonstrated that pretreatment IOP (and not TOF) is the only determinant of success after primary SLT therapy.

New glaucoma medications: latanoprostene bunod, netarsudil, and fixed combination netarsudil-latanoprost

Reduction of intraocular pressure is the only proven method to treat glaucoma. Initial treatment of glaucoma commonly involves using anti-glaucoma medications either as monotherapy or combination therapy. Studies on aqueous humour dynamics have contributed to our understanding of aqueous outflow mechanisms that have led to the discovery of new drugs. Three new drugs (latanoprostene bunod 0.24%, netarsudil 0.02%, and fixed combination netarsudil 0.02% -latanoprost 0.005%) have been introduced recently in the market with novel mechanisms of action. Latanoprostene bunod 0.024% is a nitric oxide-donating prostaglandin F2α analogue which increases the aqueous outflow both by uveoscleral and trabecular pathways. Netarsudil 0.02% is a potent Rho kinase/norepinephrine transporter inhibitor acting by increasing the trabecular outflow, decreasing the aqueous production, and possibly decreasing the episcleral venous pressure. This review highlights the role of these drugs in the management of glaucoma, with an overview of the major clinical trials on their efficacy, safety, and tolerability.

Aqueous Humor Dynamics in Uveitic Eyes

PURPOSE

To investigate aqueous humor dynamics in uveitic eyes.

DESIGN

Cross-sectional study.

PARTICIPANTS

Patients with recurrent (≥3 attacks) anterior uveitis (now quiescent) and being treated for glaucoma or ocular hypertension (OHT) (Group 1), previous recurrent anterior uveitis (≥3 attacks) without glaucoma or OHT (Group 2), and normal subjects with no ocular problems and IOP < 21 mm Hg at screening (control group; Group 3).

METHODS

Patients had one-off measurements. Group 1 patients who were on antihypertensives were washed out for a 4-week period, prior to their study measurements. Main outcome measures were tonographic outflow facility, aqueous humor flow rate, and uveoscleral outflow.

RESULTS

One hundred and one patients were screened between February 2014 and February 2017. Nine patients did not meet the inclusion criteria. Groups 1 and 3 each included 30 patients, and Group 2 included 32 patients. The mean intraocular pressure was higher in Group 1 compared to the others (25 ± 10.2 mm Hg in Group 1 vs 16 ± 2.7 mm Hg in Group 2 vs 16 ± 2.2 mm Hg in Group 3, P < .001). The tonographic outflow facility was lower in Group 1 compared to the others (0.18 ± 0.1 μL/min/mm Hg in Group 1 vs 0.25 ± 0.1 μL/min/mm Hg in Group 2 vs 0.27 ± 0.1 μL/min/mm Hg in Group 3, P = .005). However, aqueous humor flow rate was not statistically different (2.47 ± 0.9 μL/min in Group 1 vs 2.13 ± 0.9 μL/min in Group 2 vs 2.25 ± 0.7 μL/min in Group 3, P = .3). There was also no significant difference in calculated uveoscleral outflow.

CONCLUSION

This is the first aqueous humor dynamics study in patients with uveitic glaucoma/OHT and recurrent anterior uveitis compared with age-matched controls. We have demonstrated that the elevated intraocular pressure seen in the uveitic glaucoma/OHT eyes (3-6 attacks) was due to reduced tonographic outflow facility. The aqueous humor flow rate was not detectibly different, nor did the calculated uveoscleral outflow demonstrate any discernible difference. However, the exact mechanism remains to be elucidated.

Fixed combination netarsudil-latanoprost for the treatment of glaucoma and ocular hypertension

Introduction: Reduction of intraocular pressure (IOP) is the only known modifiable risk factor for prevention and treatment of glaucoma. Rho-kinase (ROCK) inhibitors are a new class of glaucoma medications introduced recently with novel mechanisms of action and favorable safety profiles. Latanoprost, a common first line drug used for treatment of glaucoma, does not adequately control pressures in all cases. Addition of more than one anti-glaucoma medication affects patient compliance and adherence. Fixed-combination eye drops are combinations of two or more active drugs in a single dosage form, thus simplify dosing. New to this group is the fixed combination netarsudil- latanoprost (FCNL).Area covered: This review focuses on FCNL, its pharmacodynamics and pharmacokinetics. It also details the efficacy and safety of individual drugs compared to FCNL.Expert opinion: The combination of latanoprost and netarsudil is a potent medication and modulates all known targets for IOP reduction in a single drop and has been shown to be more effective than either drug alone. FCNL is an alternative for those with inadequately controlled IOP on a prostaglandin analog alone, as well as those for whom a simplified regimen is desirable, or those who are not good candidates for other classes of glaucoma medications.

How many aqueous humor outflow pathways are there?

The aqueous humor (AH) outflow pathways definition is still matter of intense debate. To date, the differentiation between conventional (trabecular meshwork) and unconventional (uveoscleral) pathways is widely accepted, distinguishing the different impact of the intraocular pressure on the AH outflow rate. Although the conventional route is recognized to host the main sites for intraocular pressure regulation, the unconventional pathway, with its great potential for AH resorption, seems to act as a sort of relief valve, especially when the trabecular resistance rises. Recent evidence demonstrates the presence of lymphatic channels in the eye and proposes that they may participate in the overall AH drainage and intraocular pressure regulation, in a presumably adaptive fashion. For this reason, the uveolymphatic route is increasingly thought to play an important role in the ocular hydrodynamic system physiology. As a result of the unconventional pathway characteristics, hydrodynamic disorders do not develop until the adaptive routes cannot successfully counterbalance the increased AH outflow resistance. When their adaptive mechanisms fail, glaucoma occurs. Our review deals with the standard and newly discovered AH outflow routes, with particular attention to the importance they may have in opening new therapeutic strategies in the treatment of ocular hypertension and glaucoma.

Effect of a Topical Combination of Latanoprost and Pranoprofen on Intraocular Pressure and the Ocular Surface in Open-Angle Glaucoma Patients

Objective

A prospective study was performed to observe the effects of nonsteroidal anti-inflammatory drug (NSAID) eyedrops on intraocular pressure (IOP) and the ocular surface in primary open-angle glaucoma (POAG) patients treated with 0.005% latanoprost eyedrops.

Methods

Forty-eight subjects were randomized into two study groups (NSAID and control). Latanoprost was continued for 10 weeks in all subjects. At the end of week 4, pranoprofen was added in the NSAID group, and treatment lasted for 4 weeks, whereas patients in the control group were treated with latanoprost alone. IOP was measured in both groups every 2 weeks, and the changes in the ocular surface in the NSAID group were evaluated once a month.

Results

Pranoprofen addition resulted in a decrease in IOP in the NSAID group compared to the control group (p < 0.01). After pranoprofen was discontinued, IOP significantly increased in the NSAID group (p < 0.01), remaining approximately at the same IOP as when they were being treated with latanoprost alone. During the same examination, no significant variations in IOP were found in the control group. Patients who were treated with latanoprost alone showed gradual improvements in ocular surface symptom scores and conjunctival hyperemia scores during the first four weeks of treatment (p < 0.01). When pranoprofen eyedrops were added, ocular surface symptom scores decreased (p < 0.01), but conjunctival hyperemia scores did not change significantly.

Conclusions

For POAG patients treated with latanoprost, the combination of pranoprofen can not only significantly enhance the latanoprost-induced IOP-lowering effect but also relieve the uncomfortable ocular symptoms caused by latanoprost.

Efficacy of the combination of carteolol hydrochloride + latanoprost in the treatment of glaucoma and ocular hypertension

INTRODUCTION

The only evidence-based mechanism for prevention and treatment of glaucomatous optic neuropathy is decreasing the intraocular pressure (IOP). Prescribing multiple ocular hypotensive agents, such as the combination of carteolol and latanoprost, may synergistically improve IOP; however, doing so may increase the complexity of a medication regimen, in turn, impairing patient adherence. Fixed-combination glaucoma medications offer convenience and effectiveness. New to this class of glaucoma medication is fixed combination carteolol-latanoprost (FCCL). Area covered: This review intends to give the reader a better understanding of the efficacy of the combination of carteolol and latanoprost separately, and where FCCL fits into the vast medical arsenal of IOP drops. Furthermore, it outlines the particular pharmacologic mechanisms targeted, the pharmacokinetics, effectiveness, the advantages of fixed-combination administration, and tolerability. Expert opinion: The combination of carteolol and latanoprost, separately or in a fixed-combination, is more effective than either drug alone. Given the early stage in development of FCCL, it has yet to be determined how FCCL compares to other fixed-combination medications. However, pending further approval, fixed-combination carteolol-latanoprost may represent a reasonable alternative for a patient whose IOP is inadequately controlled on a prostaglandin analog alone and for whom a simplified combination is preferred.

[Latanoprost in hypotensive therapy of glaucoma]

The review presents an analysis of therapeutic effectiveness, safety and pharmacokinetics of latanoprost - the reference representative of the prostaglandin group, summarizes the experience of its clinical use in glaucoma as monotherapy and in combination with antihypertensive drugs of other pharmacological groups, its possible effect on the inflammatory process in the anterior segment of the eye, as well as its probable participation in the development of macular edema. The article also gives a recount of relevant local and systemic adverse events.

Effects of sustained daily latanoprost application on anterior chamber anatomy and physiology in mice

Latanoprost is a common glaucoma medication. Here, we study longitudinal effects of sustained latanoprost treatment on intraocular pressure (IOP) in C57BL/6J mice, as well as two potential side-effects, changes in iris pigmentation and central corneal thickness (CCT). Male C57BL/6J mice were treated daily for 16 weeks with latanoprost. Control mice were treated on the same schedule with the preservative used with latanoprost, benzalkonium chloride (BAK), or handled, without ocular treatments. IOP and CCT were studied at pre-treatment, 2 "early" time points, and 2 "late" time points; slit-lamp analysis performed at a late time point; and expression of corneal and iridial candidate genes analyzed at the end of the experiment. Latanoprost lowered IOP short, but not long-term. Sustained application of BAK consistently resulted in significant corneal thinning, whereas sustained treatment with latanoprost resulted in smaller and less consistent changes. Neither treatment affected iris pigmentation, corneal matrix metalloprotease expression or iridial pigment-related genes expression. In summary, latanoprost initially lowered IOP in C57BL/6J mice, but became less effective with sustained treatment, likely due to physiological adaptation. These results identify a new resource for studying changes in responsiveness associated with long-term treatment with latanoprost and highlight detrimental effects of commonly used preservative BAK.

Targeting Serotonin 2A and Adrenergic α1 Receptors for Ocular Antihypertensive Agents: Discovery of 3,4-Dihydropyrazino[1,2-b]indazol-1(2H)-one Derivatives

Glaucoma affects millions of people worldwide and causes optic nerve damage and blindness. The elevation of the intraocular pressure (IOP) is the main risk factor associated with this pathology, and decreasing IOP is the key therapeutic target of current pharmacological treatments. As potential ocular hypotensive agents, we studied compounds that act on two receptors (serotonin 2A and adrenergic α₁ ) linked to the regulation of aqueous humour dynamics. Herein we describe the design, synthesis, and pharmacological profiling of a series of novel bicyclic and tricyclic N2-alkyl-indazole-amide derivatives. This study identified a 3,4-dihydropyrazino[1,2-b]indazol-1(2H)-one derivative with potent serotonin 2A receptor antagonism, >100-fold selectivity over other serotonin subtype receptors, and high affinity for the α₁ receptor. Moreover, upon local administration, this compound showed superior ocular hypotensive action in vivo relative to the clinically used reference compound timolol.

Prostaglandin FP receptor antagonists: discovery, pharmacological characterization and therapeutic utility

In contrast to the availability of potent and selective antagonists of several prostaglandin receptor types (including DP₁ , DP₂ , EP and TP receptors), there has been a paucity of well-characterized, selective FP receptor antagonists. The earliest ones included dimethyl amide and dimethyl amine derivatives of PGF_2α , but these have failed to gain prominence. The fluorinated PGF_2α analogues, AL-8810 and AL-3138, were subsequently discovered as competitive and non-competitive FP receptor antagonists respectively. Non-prostanoid structures, such as the thiazolidinone AS604872, the D-amino acid-based oligopeptide PDC31 and its peptidomimic analogue PDC113.824 came next, but the latter two are allosteric inhibitors of FP receptor signalling. AL-8810 has a sub-micromolar in vitro potency and ≥2 log unit selectivity against most other PG receptors when tested in several cell- and tissue-based functional assays. Additionally, AL-8810 has demonstrated therapeutic efficacy as an FP receptor antagonist in animal models of stroke, traumatic brain injury, multiple sclerosis, allodynia and endometriosis. Consequently, it appears that AL-8810 has become the FP receptor antagonist of choice. LINKED ARTICLES: This article is part of a themed section on Eicosanoids 35 years from the 1982 Nobel: where are we now? To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.8/issuetoc.

Effect of phacoemulsification on facility of outflow

Purpose

Phacoemulsification has been shown to reduce intraocular pressure (IOP). The mechanism of action is thought to be via increased trabecular outflow facility. However, studies on the relationship between phacoemulsification and outflow facility have been inconsistent. This study intended to examine the change in electronic Schiotz tonographic outflow facility (TOF) and IOP measurements following phacoemulsification.

Methods

Patients who were due to undergo a standard clear corneal incision phacoemulsification with intraocular lens (IOL) implantation, at St Thomas’ Hospital, were invited to participate in this study. IOP was measured using Goldmann’s applanation tonometer, and TOF was measured by electronic Schiotz tonography at baseline and at 3, 6 and 12 months postoperatively.

Results

Forty-one patients were recruited. Tonography data for 27 patients were reliable and available at all time points. Eleven cases had primary open angle glaucoma and cataract, while 16 patients had cataract only. Mean IOP reduced at every time point postoperatively significantly compared with baseline. TOF improved significantly after cataract extraction at all time points (baseline of 0.14±0.06 vs 0.18±0.09 at 3 months, P=0.02 and 0.20±0.09 at 6 months, P=0.003, 0.17±0.07 µL/min mmHg at 12 months, P=0.04). Five contralateral eyes of patients with cataracts only who did not have any intraocular surgery during the follow-up period were used as comparison. Their IOP and TOF did not change significantly at any postoperative visits.

Conclusion

This is the first study using electronic Schiotz tonography with documented anterior chamber depth and gonioscopy after modern cataract surgery (CS) with phacoemulsification and IOL implantation. We demonstrated that phacoemulsification increases TOF and this fully accounts for the IOP reduction following CS.

ISTCRN registration number

ISRCTN04247738.

Bimatoprost sustained-release intracameral implant reduces episcleral venous pressure in dogs

OBJECTIVE

To determine the effect of a bimatoprost sustained-release intracameral implant (Bimatoprost SR) on episcleral venous pressure (EVP) in normal dogs.

METHODS

Normotensive beagle dogs were randomized to receive Bimatoprost SR 30 μg (n = 7) or sham injection (needle insertion only, n = 7) in one eye on day 1. EVP was measured with an episcleral venomanometer through day 65. Episcleral aqueous outflow vessels were identified using fluorescence imaging following intracameral injection of indocyanine green in one additional animal. A separate cohort of dogs that had been trained for conscious intraocular pressure (IOP) measurements received Bimatoprost SR 30 μg (n = 8) in one eye; IOP was evaluated through day 66.

RESULTS

Baseline mean EVP was 10.0 mmHg in the Bimatoprost SR group and 10.4 mmHg in the sham group. Eyes treated with Bimatoprost SR exhibited a transient increase in mean EVP that peaked at day 8, followed by a decrease to levels below baseline. From day 29 to day 65, the change in mean EVP from baseline ranged from -2.4 to -3.9 mmHg (P < 0.05 vs. sham). Baseline mean IOP in eyes treated with Bimatoprost SR was 14.9 mmHg, and a steady IOP reduction was maintained through day 66. Bimatoprost SR-treated eyes exhibited a selective, sustained dilation of aqueous outflow vessels that was not observed in sham-treated eyes.

CONCLUSIONS

In normal dogs, Bimatoprost SR was associated with a transient increase in EVP followed by a sustained decrease. Changes in EVP were accompanied by a sustained dilation of aqueous outflow vessels.

The Effect of Latanaprost on Intraocular Inflammation and Macular Edema

There is debate concerning whether the use of Latanoprost in early postoperative period of cataract surgery and in glaucoma patients with uveitis as it may aggravate the inflammation and results in macular edema (ME), because of blood-ocular barrier disruption. However, there is no solid evidence for disruption of blood-ocular barrier with Latanoprost and aggravation of uveitis or ME formation. Similar to pseudophakic ME, the imaging ME in cases claimed to be secondary to Latanoprost is greater than clinical ME, happens mostly in complicated surgeries, and the vast majority resolve within weeks to months with using a non-steroidal anti-inflammatory drug. The current literature suggests that Latanoprost can be used in patients with uveitis and early after cataract surgery with or without concomitant topical non-steroidal anti-inflammatory drugs that are currently used by many ophthalmologists as a preventive measure for ME even in non-glaucoma uncomplicated cataract surgeries.

Efficacy and safety of bimatoprost in glaucoma and ocular hypertension in non-responder patients

AIM

To establish the efficacy and safety of bimatoprost 0.03% monotherapy in glaucoma and ocular hypertension (OHT) patients with inadequate intraocular pressure (IOP)on current therapy.

METHODS

Pre- and post-switch IOPs were analyzed for 59 consecutive patients who were switched from current therapy to bimatoprost monotherapy between 2011-2015. Demographic information, diagnosis, and any adverse events were recorded. Change in IOP post-pre switch was analyzed using a 2-sided Student's paired t-test at the 5% significance level.

RESULTS

There was a statistically significant mean reduction in IOP at the first follow up visit, which was maintained at subsequent follow up visits for patients regardless of diagnosis, or pre-switch treatment (P<0.001). Subgroup analysis also demonstrated a statistically significant mean reduction in IOP when looking at OHT patients only, as well as patients with any diagnosis switched from latanoprost monotherapy to bimatoprost monotherapy (P<0.001).

CONCLUSION

This is the largest independent data set which supports switching glaucoma patients with poor response to current treatment onto bimatoprost monotherapy before considering other adjuvant medical or more invasive therapy.

Long-term Follow-up of Patients receiving Intraocular Pressure-lowering Medications as Cataract Surgery Candidates: A Case-control Study

AIM

In this study, we reviewed demographics and biometric characteristics among patients receiving chronic β-blockers and prostaglandins (PGs) for primary open-angle glaucoma. We compared the age at the time of cataract surgery in different patient groups and in a control group which was not under any medication.

MATERIALS AND METHODS

Retrospective chart review of glau-comatous patients who underwent cataract extraction at the Department of Ophthalmology of the University Hospital of Heraklion, Crete, Greece, between January 1998 and December 2016 was done. Age at cataract surgery, axial length (AL), and preoperative and postoperative best-corrected visual acuities (BCVAs) were recorded. A cohort of patients without glaucoma who were operated for cataract extraction was also evaluated.

RESULTS

In all, 320 patients were reviewed. There were significant results in mean age difference between the beta-antagonist and the PG group [3.05 years, 95% confidence interval (CI) 1.54-4.57] and between the beta-antagonist group with the patients receiving a combined therapy (3.02 years, 95% CI 1.14-4.91). No significant difference was found between the PG and the combination group. All the three treated groups had a significant lower mean age than the control group at the time of cataract surgery.

CONCLUSION

Based on our study, we concluded that there might be a possible association between chronic treatment with beta-antagonist agents and earlier cataract surgical time in the treated eye.

CLINICAL SIGNIFICANCE

Intraocular pressure control is often usually achieved using ophthalmic agents. Their topical and systemic effects should be monitored precisely. Earlier cataract formation might be an important side effect which the physician has to keep in mind before choosing the suitable medication.How to cite this article: Bontzos G, Agiorgiotakis M, Detorakis ET. Long-term Follow-up of Patients receiving Intraocular Pressure-lowering Medications as Cataract Surgery Candidates: A Case-control Study. J Curr Glaucoma Pract 2017;11(3):107-112.

Unconventional aqueous humor outflow: A review

Aqueous humor flows out of the eye primarily through the conventional outflow pathway that includes the trabecular meshwork and Schlemm's canal. However, a fraction of aqueous humor passes through an alternative or 'unconventional' route that includes the ciliary muscle, supraciliary and suprachoroidal spaces. From there, unconventional outflow may drain through two pathways: a uveoscleral pathway where aqueous drains across the sclera to be resorbed by orbital vessels, and a uveovortex pathway where aqueous humor enters the choroid to drain through the vortex veins. We review the anatomy, physiology and pharmacology of these pathways. We also discuss methods to determine unconventional outflow rate, including direct techniques that use radioactive or fluorescent tracers recovered from tissues in the unconventional pathway and indirect methods that estimate unconventional outflow based on total outflow over a range of pressures. Indirect methods are subject to a number of assumptions and generally give poor agreement with tracer measurements. We review the variety of animal models that have been used to study conventional and unconventional outflow. The mouse appears to be a promising model because it captures several aspects of conventional and unconventional outflow dynamics common to humans, although questions remain regarding the magnitude of unconventional outflow in mice. Finally, we review future directions. There is a clear need to develop improved methods for measuring unconventional outflow in both animals and humans.

Factors Related to Prostaglandin-Associated Periorbitopathy in Glaucoma Patients

PURPOSE

To determine factors related to prostaglandin-associated periorbitopathy (PAP) and its prevalence in glaucoma or ocular hypertension (OHT) patients using prostaglandins analogs (PGAs).

DESIGN

A cross-sectional study.

METHODS

A study of glaucoma or OHT patients, using topical PGAs for at least 3 months, was performed. Eyes treated with PGAs were photoraphed and independently evaluated for PAP by 2 glaucoma specialists using at least 4 out of 7 clinical appearances. The factors of interest were sex, age, body mass index (BMI), types of glaucoma, types of PGAs, duration of PGA use, and concurrent 0.5% timolol. Univariate (χ2 test) and multivariate (multiple logistic regression) analyses assessing risk factors for PAP were performed to estimate the odds ratios (OR) with 95% conidence intervals (CIs).

RESULTS

One hundred thirty-four eyes from 134 patients were included. Seventy (52.2%), 21 (15.7%), and 43 (32%) eyes received components of latanoprost, travoprost, and bimatoprost, respectively. Prevalence of PAP was 44.8% (95% CI, 36.3 to 53.3). Older age >60 years (OR, 3.0; 95% CI, 1.2 to 7.8), bimatoprost (OR, 4.0; 95% CI, 1.6 to 9.5), travoprost (OR, 3.3; 95% CI, 1.1 to 10.1), and timolol (OR, 2.9; 95% CI, 1.3 to 6.8) were at risk of PAP development. In addition, BMI ≥23 kg/㎡ (OR, 0.3; 95% CI, 0.1 to 0.7) was reversely associated with PAP.

CONCLUSIONS

Older age, bimatoprost, or travoprost were associated with PAP, whereas high BMI was found as a protective factor. Interestingly, timolol possibly precipitated periorbital change when in use with prostaglandins.

Comparison of Aqueous Outflow Facility Measurement by Pneumatonography and Digital Schiøtz Tonography

Purpose

It is not known if outflow facilities measured by pneumatonography and Schiøtz tonography are interchangeable. In this study we compared outflow facility measured by pneumatonography to outflow facility measured by digital Schiøtz tonography.

Methods

Fifty-six eyes from 28 healthy participants, ages 41 to 68 years, were included. Intraocular pressure (IOP) was measured in the sitting and supine positions with a pneumatonometer. With the subject in the supine position, IOP was recorded for 2 minutes by using a pneumatonometer with a 10-g weight and for 4 minutes by using a custom digital Schiøtz tonometer. Outflow facility was determined from the changes in pressure and intraocular volume and a standard assumed ocular rigidity coefficient for each instrument, respectively, and by using an ocular rigidity coefficient calculated by measuring pressure without and with a weight added to the pneumatonometer tip.

Results

The outflow facility was 0.29 ± 0.09 μL/min/mm Hg by Schiøtz tonography and 0.24 ± 0.08 μL/min/mm Hg by pneumatonography (P < 0.001) when using the standard assumed constant ocular rigidity coefficient. Mean calculated ocular rigidity coefficient was 0.028 ± 0.01 μL-1, and outflow facility determined by using this coefficient was 0.23 ± 0.08 μL/min/mm Hg by Schiøtz tonography and 0.21 ± 0.07 μL/min/mm Hg by pneumatonography (P = 0.003). Outflow facilities measured by the two devices were correlated when the ocular rigidity was assumed (r = 0.60, P < 0.001) or calculated (r = 0.70, P < 0.001).

Conclusions

Outflow facilities measured by pneumatonography were correlated with those measured by Schiøtz tonography, but Schiøtz tonography reported approximately 10% to 20% higher facilities when using the standard method. When ocular rigidity was determined for each eye, differences were smaller. Measurements from these devices cannot be compared directly.

[Ocular hydrodynamics after phacoemulsification cataract surgery in patients with primary open-angle glaucoma]

AIM

To investigate parameters of intraocular fluid outflow after phacoemulsification of cataract in patients with primary open-angle glaucoma (POAG).

MATERIAL AND METHODS

The study involved 153 cataract patients (153 eyes), most of whom also had POAG. The patients were divided into three groups: group 1 - 51 patients (51 eyes) with cataract but no glaucoma, group 2 - 51 patients (51 eyes) with cataract and early POAG, and group 3 - 51 patients (51 eyes) with cataract and advanced POAG. All of them underwent non-contact pneumatic tonometry, tonography, and tonography with vacuum compression (Glau-Test60) before and after surgery (phacoemulsification of cataract with implantation of a posterior chamber intraocular lens (IOL)). The follow-up period was 6 months.

RESULTS AND DISCUSSION

Phacoemulsification surgery with IOL implantation was able to reduce intraocular pressure in non-glaucoma cataract patients by 3 to 5 mmHg in 21.57% of cases and by more than 5 mmHg in 58.8% of cases. In patients with early and advanced glaucoma, a 3 to 5 mmHg decrease occurred in 33.3% and 13.7% of cases, respectively, and a more than 5 mmHg decrease - in 49.02% and 56.9%, respectively. This reduction is due to activation of intraocular fluid outflow.

CONCLUSION

A postoperative increase in trabecular and uveoscleral outflow has been detected in all groups. The change was more significant in non-glaucoma patients and those with early disease.

Critical evaluation of latanoprostene bunod in the treatment of glaucoma

Latanoprostene bunod (LBN) is a novel nitric oxide-donating prostaglandin F_2α receptor agonist in clinical development for intraocular pressure lowering in open-angle glaucoma and ocular hypertension. Currently in Phase III clinical trials in the USA, European Union, and Japan, LBN has demonstrated promising efficacy while maintaining safety and tolerability. We review preclinical and clinical developmental efforts and evaluate the potential role of LBN monotherapy in the management of open-angle glaucoma and ocular hypertension. The current LBN clinical development program comprises eight trials, four of which have resulted in publication of complete methodology and outcomes. We additionally pool adverse events data to determine incidences across three pivotal studies. Evidence thus far indicates that LBN may be a safe and effective ocular hypotensive agent, although the potential neuroprotective effects and the impact on visual field loss remain to be evaluated.

Aqueous outflow facility after phacoemulsification with or without goniosynechialysis in primary angle closure: a randomised controlled study

BACKGROUND

Goniosynechialysis (GSL) to remove peripheral anterior synechiae (PAS) alongside standard cataract surgery has potential theoretical advantages, Published randomised trials, however, have not shown conclusive functional benefits and aqueous outflow changes following GSL are unknown. This study aimed to compare electronic Shiøtz tonographic aqueous outflow facility (TOF) following phacoemulsification with or without GSL in patients with primary angle closure (PAC) and PAC glaucoma. Secondary outcomes were changes in intraocular pressure (IOP) and use of glaucoma medications.

METHODS

Prospective randomised pilot study of 26 patients on glaucoma medication, with ≥90° PAS and significant lens opacity. Patients were randomised 1:1 to receive phacoemulsification with intraocular lens (IOL) implantation only (phaco) or phacoemulsification with IOL plus GSL (phaco-GSL).

RESULTS

Fourteen patients were randomised to phaco-GSL and 12 to phaco alone. TOF increased with phaco-GSL from 0.099±0.07 μL/min/mm Hg to 0.194±0.07, μL/min/mm Hg, p=0.0006, while the phaco group showed no significant change. IOP reduced in both groups, but reduced significantly more following phaco-GSL (46.0%) compared with phaco alone (27.6%, p=0.04). Medication use and extent of PAS only reduced with phaco-GSL, from 0.923±0.86 to 0.384±0.18 medications, p=0.0279, and from 249.2±83.4 to 110.8±53.9° PAS, 6 months postoperatively. No serious adverse events occurred in either group.

CONCLUSIONS

Eyes randomised to both surgical groups had similar and good outcomes at 6 months in this pilot study. However, only eyes undergoing GSL combined with standard phacoemulsification had significantly increased TOF, reduced glaucoma medication dependence and PAS postoperatively. GSL should therefore be considered in such patients.

TRIAL REGISTRATION NUMBER

NCT00719290, Results.