Effects of bimatoprost 0.03% on ocular hemodynamics in normal tension glaucoma

Cytotoxicity, Mitochondrial Functionality, and Redox Status of Human Conjunctival Cells after Short and Chronic Exposure to Preservative-Free Bimatoprost 0.03% and 0.01%: An In Vitro Comparative Study

Prostaglandin analogues (PGAs), including bimatoprost (BIM), are generally the first-line therapy for glaucoma due to their greater efficacy, safety, and convenience of use. Commercial solutions of preservative-free BIM (BIM 0.03% and 0.01%) are already available, although their topical application may result in ocular discomfort. This study aimed to evaluate the in vitro effects of preservative-free BIM 0.03% vs. 0.01% in the human conjunctival epithelial (HCE) cell line. Our results showed that long-term exposure to BIM 0.03% ensues a significant decrease in cell proliferation and viability. Furthermore, these events were associated with cell cycle arrest, apoptosis, and alterations of ΔΨ_m. BIM 0.01% does not exhibit cytotoxicity, and no negative influence on conjunctival cell growth and viability or mitochondrial activity has been observed. Short-time exposure also demonstrates the ability of BIM 0.03% to trigger reactive oxygen species (ROS) production and mitochondrial hyperpolarisation. An in silico drug network interaction was also performed to explore known and predicted interactions of BIM with proteins potentially involved in mitochondrial membrane potential dissipation. Our findings overall strongly reveal better cellular tolerability of BIM 0.01% vs. BIM 0.03% in HCE cells.

Tolerability and efficacy of bimatoprost 0.01 % in patients with open-angle glaucoma or ocular hypertension evaluated in the Taiwanese clinical setting: the Asia Pacific Patterns from Early Access of Lumigan 0.01 % (APPEAL Taiwan) study

BACKGROUND

In randomized, controlled trials of open-angle glaucoma (OAG) or ocular hypertension (OHT), bimatoprost 0.01 % improved tolerability while retaining the intraocular pressure (IOP)-lowering efficacy of bimatoprost 0.03 %. Given geographic/racial differences in glaucoma presentation, the APPEAL study assessed the occurrence and severity of hyperemia produced by bimatoprost 0.01 %, and its efficacy, in the Taiwanese clinical setting.

METHODS

In this multicenter, open-label, observational study, treatment-naïve and previously treated patients with OHT or OAG received once-daily bimatoprost 0.01 % for 12 weeks. Hyperemia (primary endpoint) was graded at baseline, week 6, and week 12 using a photonumeric scale (0, +0.5, +1, +2, +3), grouped (≤ +1, none to mild; ≥ +2, moderate to severe), and reported as unchanged from baseline, improved, or worsened. IOP assessments followed the same schedule. Supplemental efficacy analyses were conducted based on previous therapies.

RESULTS

The intent-to-treat population (N = 312) included treatment-naïve (13.5 %) and previously treated (86.5 %) patients; mean age was 53.3 years. At baseline, 46.3 % of previously treated patients were receiving prostaglandin analog (PGA) monotherapy. At week 12, 91.2 %, 5.9 %, and 2.9 % of treatment-naïve patients exhibited unchanged, worsened, and improved hyperemia from baseline, respectively; 77.9 %, 12.9 %, and 9.2 % of previously treated patients showed no change, worsening, and improvement, respectively. There were no statistically significant shifts in hyperemia severity in either group, or in subgroups based on previous use of any PGA, any non-PGA, latanoprost, or travoprost monotherapies. In treatment-naïve patients, mean IOP reduction from baseline (18.0 ± 3.8 mm Hg) was 3.6 mm Hg at week 12 (P < 0.0001); 83.3 % had baseline IOP ≤ 21 mm Hg. In previously treated patients, mean additional IOP reduction from baseline (17.8 ± 3.9 mm Hg) was 2.6 mm Hg (P < 0.0001); similar results were observed in patient subgroups based on previous therapies.

CONCLUSIONS

In the Taiwanese clinical setting, bimatoprost 0.01 % provided significant IOP lowering in treatment-naïve patients (regardless of baseline IOP) and previously treated patients (even those with relatively low IOP on other therapies), while causing no significant changes in hyperemia from baseline.

TRIAL REGISTRATION

Clinicaltrials.gov NCT01814761 . Registered 18 March 2013.

Nonresponders to Prostaglandin Analogs Among Normal-Tension Glaucoma Patients

PURPOSE

To investigate patients whose intraocular pressure (IOP) did not decrease after treatment using a prostaglandin analog (nonresponders).

METHODS

This was an open-label, retrospective, case series study from a single institution. We retrospectively investigated the mean IOP reduction rates, and the proportions of nonresponders, among normal tension glaucoma (NTG) patients (209 cases, 209 eyes) treated using 1 of 4 prostaglandin analogs: latanoprost (40 patients), travoprost (64 patients), tafluprost (52 patients), or bimatoprost (53 patients). Absolute IOP was compared with pretreatment values for all 4 groups at the first and second visits after commencement of prostaglandin analog monotherapy. The IOP reduction rate was compared between groups. The proportion of nonresponders, defined as patients with IOP reduction rate <10% at both visits, was calculated in each group.

RESULTS

The average IOP had significantly decreased from the pretreatment value at the first visit after treatment; the average IOP reduction rate ranged from 15.3% to 22.6%. The IOP reduction rate in the bimatoprost group was significantly higher than those in the travoprost and tafluprost groups (P < 0.001). We identified 6 nonresponders (15.0%) in the latanoprost group, 9 (14.1%) in the travoprost group, 4 (7.7%) in the tafluprost group, and none (0.0%) in the bimatoprost group; nonresponse rates were significantly lower in the bimatoprost group than in the other groups (P ≤ 0.05).

CONCLUSION

Among NTG patients treated using prostaglandin analogs, from 0% to 15% were classified as nonresponders, depending on the prostaglandin analog used. The proportion of nonresponders was significantly lower in the bimatoprost group.

Highly stereoselective synthesis of cyclopentanes bearing four stereocentres by a rhodium carbene-initiated domino sequence

Stereoselective synthesis of a cyclopentane nucleus by convergent annulations constitutes a significant challenge for synthetic chemists. Though a number of biologically relevant cyclopentane natural products are known, more often than not, the cyclopentane core is assembled in a stepwise fashion due to lack of efficient annulation strategies. Herein, we report the rhodium-catalyzed reactions of vinyldiazoacetates with (E)-1,3-disubstituted 2-butenols generate cyclopentanes, containing four new stereogenic centers with very high levels of stereoselectivity (99% ee, >97 : 3 dr). The reaction proceeds by a carbene–initiated domino sequence consisting of five distinct steps: rhodium–bound oxonium ylide formation, [2,3]-sigmatropic rearrangement, oxy-Cope rearrangement, enol–keto tautomerization, and finally an intramolecular carbonyl ene reaction. A systematic study is presented detailing how to control chirality transfer in each of the four stereo-defining steps of the cascade, consummating in the development of a highly stereoselective process.

Effects of antiglaucoma drugs on blood flow of optic nerve heads and related structures

An association between glaucoma development or progression and compromised ocular blood flow has been postulated as a result of population-based studies and prospective cohort studies. Blood flow in the optic nerve head (ONH) is of primary importance in the pathogenesis of glaucoma. The potential to modify the blood flow in the ONH and its related structures has been reported in various agents, including topical antiglaucoma drugs and systemic drugs such as calcium channel antagonists, which are reviewed in this manuscript. Clinical implications of the improvement in ocular blood flow on the treatment of glaucomatous optic neuropathy require further investigation.

Bimatoprost: a review of its use in open-angle glaucoma and ocular hypertension

Bimatoprost (Lumigan) is a synthetic prostamide that reduces intraocular pressure (IOP) by increasing the outflow of aqueous humour. In patients with open-angle glaucoma or ocular hypertension, long-term treatment (for up to 48 months) with once-daily bimatoprost 0.03% ophthalmic solution was more effective than timolol twice daily in providing a sustained and stable reduction in IOP. Bimatoprost 0.03% ophthalmic solution demonstrated efficacy similar to, or greater than, the prostaglandin analogues latanoprost and travoprost in reducing IOP and achieving target IOP levels. Switching to bimatoprost was as effective in maintaining diurnal IOP control as switching to a fixed combination of latanoprost/timolol (in patients with IOP levels controlled with a nonfixed combination of latanoprost plus timolol), and similarly, or more, effective in lowering IOP and providing overall diurnal IOP control than switching to a combination of dorzolamide/timolol (in patients with IOP inadequately controlled with other antiglaucoma agents including timolol). Treatment with bimatoprost was generally well tolerated, with conjunctival hyperaemia (mostly mild), growth of eyelashes and ocular pruritus being commonly reported. Other adverse events included increases in the pigmentation of the iris, perorbital areas and eyelashes.