Intraocular pressure-lowering effects of all commonly used glaucoma drugs: a meta-analysis of randomized clinical trials

Latanoprost rescues retinal neuro-glial cells from apoptosis by inhibiting caspase-3, which is mediated by p44/p42 mitogen-activated protein kinase

The purpose of this study was to investigate whether latanoprost, a prostaglandin F2alpha analogue, has a direct anti-apoptotic effect both in retinal neuro-glial cells in culture and in diabetic retina. R28 cells, immortalized retinal neuroglial progenitor cells, were induced apoptosis by 24h serum deprivation. Serum withdrawal made up to 15% of R28 cells pyknotic and activated caspase-3 immunoreactive, and latanoprost acid suppressed apoptosis with dose dependency at an optimum concentration of 1.0 microM (P<0.001). UO126, a mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase kinase (MEK) 1 and 2 inhibitor reversed this effect. Streptozotocin induced one- or three-month diabetic rats received balanced-salt-solution (BSS) in the left eye and latanoprost eye drops in the right for 5 days. Retinal wholemount was subjected to terminal dUTP nick end labeling (TUNEL) staining, whereas eyeballs were enucleated for cleaved caspase-3 immunofluorescence. Retinal homogenates were probed for phospho- or total p44/p42 MAPK and Akt. One- and three-month diabetic retina had 30.2+/-15.3 and 23.6+/-9.0 TUNEL positive cells per 0.5 cm(2), respectively, whereas control retina had few TUNEL positive cells. Latanoprost instillation significantly reduced these cells (10.0+/-3.1 and 11.3+/-3.1 cells per 0.5 cm(2) for 1M and 3M, respectively, P<0.01), whereas BSS did not. Latanoprost also significantly reduced cleaved caspase-3 immunoreactive cells in ganglion cell and inner nuclear layers (P<0.05). Latanoprost increased phosphorylated to total protein ratio of p44/p42 MAPK (P<0.05), but not of Akt. Taken together, the present findings suggest that latanoprost rescues retinal neurons and/or glial cells from apoptosis, which is probably mediated by p44/p42 MAPK through caspase-3 inhibition.

A 6-week, double-masked, parallel-group study of the efficacy and safety of travoprost 0.004% compared with latanoprost 0:005%/timolol 0.5% in patients with primary open-angle glaucoma or ocular hypertension

OBJECTIVE

The objective of this study was to directly compare the intraocular pressure (IOP)-lowering efficacy and safety of travoprost 0.004% eyedrops with the fixed combination of latanoprost 0.005%/timolol 0.5% eyedrops in patients with primary open-angle glaucoma or ocular hypertension.

METHODS

This was a randomized, double-masked, multicenter, parallel-group, active-controlled study. Adult subjects with open-angle glaucoma (with or without pseudoexfoliation or pigment dispersion component) or ocular hypertension were eligible to participate if their IOP was inadequately controlled with > or =4 weeks of beta-blocker monotherapy, as indicated by IOP of 22 to 36 mm Hg at 9 AM at screening. Patients were randomly assigned in a 1:1 ratio to receive placebo + travoprost or latanoprost/timolol + placebo. Patients in the travoprost group administered travoprost at 9 PM and placebo at 9 AM; patients in the latanoprost/timolol group administered latanoprost/timolol at 9 AM and placebo at 9 PM. IOP measurements were performed using Goldmann applanation tonometry at 9 AM and 5 PM at the week-2 and week-6 visits. Both volunteered and elicited reports of adverse events were collected; all patients who were randomized and received > or =1 dose of study drug were included in the safety analysis.

RESULTS

One hundred ten patients were randomized, of whom 106 patients were evaluable (travoprost, n = 50; latanoprost/timolol, n = 56). There were no statistically significant differences at baseline between the treatment groups, based on age group, sex, race, iris color, or diagnosis. Mean IOP values were not statistically different between groups at baseline or during treatment. In the pooled results for 9 Am assessment at weeks 2 and 6, mean (SEM) IOP reductions for travoprost and latanoprost/timolol were 7.0 (0.5) and 6.4 (0.5) mm Hg, respectively (P = NS). Adverse events related to therapy were mild in nature, and there were no statistically significant differences between the 2 treatment groups. The most frequently experienced adverse events in the travoprost group were ocular hyperemia (9.3%), foreign body sensation (5.6%), abnormal vision (1.9%), allergic reaction (1.9%), conjunctivitis (1.9%), dacryocystitis (1.9%), eye discharge (1.9%), eye pruritus (1.9%), lid edema (1.9%), lid erythema (1.9%), and tearing (1.9%). In the latanoprost/timolol group, the most frequently experienced adverse events were cataract (1.8%), dry eyes (1.8%), eye pruritus (1.8%), foreign body sensation (1.8%), and ocular hyperemia (1.8%).

CONCLUSIONS

Mean IOP changes from baseline for travoprost 0.004% and latanoprost 0.005%/timolol 0.5% fixed combination were not significantly different at follow-up in these patients. Both medications were well tolerated.

Complex genetics of complex traits: the case of primary open-angle glaucoma

Glaucoma, which is a complex heterogeneous disease, presents an ideal case for genetic investigation. Primary open-angle glaucoma (POAG) is the commonest subtype and will be the focus of this review. When detected early, POAG is amenable to therapeutic intervention. Unfortunately, current population-based clinical screening lacks efficacy. If individuals with a genetic predisposition for developing POAG can be identified, then efficient and cost-effective population-based screening programs could be designed. Although considerable inroads have been made in understanding the natural history of POAG caused by mutations in the myocilin and optineurin genes, other POAG genes accounting for most cases remain to be identified. This review explores the genetic mechanisms that have been unequivocally linked to the glaucomatous process and then discusses potential avenues for future breakthroughs.

Changes in glaucoma treatment and achieved IOP after introduction of new glaucoma medication

PURPOSE

To describe changes in glaucoma treatment and achieved IOP (intraocular pressure) over the period 1995-2002, 4 years before and 4 years after new glaucoma drugs had become available (January 1999).

METHODS

An observational study was conducted in primary open-angle glaucoma (suspect), and ocular hypertension patients (n=1561) who had started medical treatment in 1995 or thereafter. The processes of starting, changing and intensifying medical treatment in general, and in patients with contraindications to beta-blockers before and after January 1999 were described. The change in mean IOP and the percentage of patients achieving an intraocular pressure below 18 or 22 mmHg were calculated.

RESULTS

After January 1999, a shift from starting on betaxolol to hypotensive lipids took place. This shift was more pronounced in patients with respiratory comorbidity. The percentage of patients starting on timolol did not differ between both periods. After January 1999, therapy was changed more often in the first two visits compared with the period before January 1999 (38% versus 27%, P<0.0001). In more recent years, a larger percentage of glaucoma patients were treated with two or more drugs (34% in 2002 versus 13% in 1995). Over the period 1995-2002, baseline IOP did not change (P=0.85); for mean IOP at visit 4, a trend to lower IOPs was observed (P<0.0001). More patients achieved an IOP level under 22 and 18 mmHg after January 1999 than before, 85% versus 77%, and 46% versus 33%, respectively (P<0.0001).

CONCLUSIONS

This study shows a change in process of glaucoma treatment and lower achieved IOP after new glaucoma drugs had become available.

Comparison of Diurnal Intraocular Pressure Control by Latanoprost versus Travoprost

BACKGROUND AND OBJECTIVE

Intraocular pressure (IOP) is known to be subject to daily fluctuations, the occurrence of which is a risk factor for progression of glaucoma. Control of IOP during the day by drugs is an important therapeutic target. We set out to compare the IOP control of travoprost and latanoprost taking into account the time since last instillation and the time of IOP measurement.

METHODS

This was a prospective, cross-sectional observational study with some retrospective data collection. Private ophthalmologists were selected to each recruit ten patients with primary open-angle glaucoma and/or ocular hypertension receiving either travoprost or latanoprost as monotherapy. Clinical endpoints included IOP measurements and percentage of patients attaining predefined target IOPs. Six patient subgroups were defined according to: (a) IOP measurement time: before 1200h, 1200h-1600h and after 1600h, and (b) time since last intake (<24 hours, >24 hours). Analyses comprised chi(2) and Wilcoxon tests, ANOVA, logistic regressions and adjustment by propensity score.

RESULTS

In total, 2052 patients treated with travoprost (n = 1704) or latanoprost (n = 348) participated in the study. Treatment groups were comparable at baseline, except for a longer treatment duration in latanoprost-treated patients. When the interval between the last treatment instillation and IOP measurement (treatment/IOP interval) was <24 hours (n = 1241), 82% of travoprost-treated patients attained pre-defined target IOP versus 67% with latanoprost (p < 0.0001). This difference was greatest after 1600 h, when the mean IOP was 16.5 mm Hg for travoprost-treated patients and 17.7 mm Hg for latanoprost-treated patients (p = 0.0025). When the treatment/IOP interval was >24 hours (n = 461), travoprost was superior to latanoprost, i.e. more patients using travoprost attained the predefined target IOP (78.5% vs 68.3%; p = 0.0344), and the mean IOP value was lower in the travoprost group (16.8 vs 17.8 mm Hg; p = 0.0016). After adjustments for confounding factors, similar results were obtained.

CONCLUSIONS

According to this observational survey, travoprost appears to reduce evening and mean diurnal IOP more effectively than latanoprost. Latanoprost IOP control appears to be more sensitive to time since the last dose.

Analytic review of bimatoprost, latanoprost and travoprost in primary open angle glaucoma

OBJECTIVE

The objective of this review was to evaluate different measures of efficacy of the intraocular pressure (IOP) lowering lipid class agents bimatoprost, latanoprost and travoprost in the treatment of primary open angle glaucoma. Study arms of timolol in trials including the above mentioned lipid class drugs were also included.

METHODS

MEDLINE and EMBASE were searched for randomized clinical trials including one or more of the lipid class drugs bimatoprost, latanoprost and travoprost. The study results were pooled, and the simple, weighted IOP-lowering efficacy was compared among the lipid class drugs and timolol, where data were available. Efficacy parameters were reviewed, including mean reduction of IOP and percentage of patients achieving different levels of IOP.

RESULTS

161 articles were identified of which 42 were included in the analysis. A total of 9295 patients participated in the included trials. Based on all studies, timolol on average had a weighted mean IOP reduction of 22.2%, while latanoprost, travoprost and bimatoprost had a weighted mean IOP reduction of 26.7%, 28.7% and 30.3%, respectively. Analysis of target achievement to various IOP levels shows that bimatoprost seems more efficacious than latanoprost. The direct comparisons (head-to-head studies) also show that bimatoprost is the most efficacious treatment, however it is not conclusive whether latanoprost or travoprost is better in reducing IOP.

CONCLUSIONS

This review shows that bimatoprost seems to be the most efficacious treatment in lowering IOP. Head-to-head studies confirm this.